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= Y o u will find inside 0,1% JOHN SCOTT-TAGGART'S4] " TELE-SOU N DER

1937 ALL -WAVE RADIO

PICTORIAL TELEVISION PRESENTATION

SPECIAL XMAS ARTICLES POPULAR WIRELESS December 5th, 11) ;3. "gayA NEW "H.M.V." ALL =WORLD RADIO in time AOrCitrigmaJ YEARS of laboratory experience and research preceded the public introduction of " His Master's Voice " All -Wave Radio.As the result, even low -powered trans- mitters in U.S.A., Australia, and other distant countries can be received regularly (under favourable conditions) and with good quality reproduction. Those of the new " H.M.V." All -Wave models equipped with the 7-16 metres waveband will get the television sound transmission and amateur broadcasts, too. Two -speed tuning, Vernier scale which indicates exact reception point for each short wave station to be noted, and Cathode Ray Fluid - Lightindicatorsand many other refinements are to be found in " H.M.V." All -Wave Radio. 9'etTHE BEST RECEPTION 149. All -Wave Battery Receiver, 486AC DC. All -Wave Superhet.. 3 valves. 18-5o, 195-560,9,1G NS. 4 valves (plus detector) with AVC. ON ALL WAVE=BANDS 785-200o metres. 16-50, 198-580, 750- 121_ GNS. 2000 metres. I .0 2

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" His Master's Voice," 98-108 Clerkenwell Road, London, E.C.I. Popular Wireless, December 5lit, 1936. 329

ANDTELEVISION TIMES EDITOR: G. V. Dowding Asst. Editors :A. Johnson Randall, A. S. Clark

GOOD REASONS ROYAL RADIO ON EASY TERMS RADIO NOTES & NEWS A GOOD FRIEND VERY CONFUSING LINER LINKS

Same to You On the Easy Plan " Television is from its very nature more THEunwonted chromatic ebullience of IFa gentleman calls at your house with suitable for the dissemination of all kinds our cover this week will have con- the story that he is a B.B.C. engineer, of information than for entertainment .." vinced you that this is, indeed, the senttoinvestigatecomplaintsof Christmas Number of " P.W."Without interference,do nottrusthim,gentle Alan Hunter, in the " Manchester Even- confirmation from the calendar I should reader,thoughhisvoicebe lowand ing News " : . .," If television is going have said, " Impossible," for it seems a sweet. to develop along the lines of a glorified mere no -time since last I bade you charge One plausible traveller who has been magic lantern lecture course it just isn't your glasses, and allow the laws of liquidity going round with this story always examines going to develop." and hydrostatics to lubricate your larynx. the radio set with great care, and suggests We will, however, gratefully accept this it needs a thorough overhaul with some Gate -Crashing Short -Wavers annual excuse and fill 'em up once more. instruments that are in his van " round WEEK or two ago I told you about Are you all ready ?Glasses raised ? the corner." A" Medium Wave " of Worksop, who Then here's to A Happy Christmas ... He then takes the set, vanishes round the specialises inflea -powerstation Good health, sir. . , More hair reception.Iforgot to mention on your chest. . . Bung -ho ! wogfzfz_reggoioggfigoi,gAgufigf,ricwgfe=iczm ziglig.f,gAigvAgAm. the curious fault that appeared on hisset. For absolutely no 800 Good Reasons reason at all he gets short-wave HAVING moistened theold iReabers stations who work between thirty membranous linings, let us and fifty metres walking in on his congratulate ourselves-old set when itis adjusted at about pals and newcomers alike-on the 20 metres. marvellous way in which radio Madrid E A Q is one of these perennially maintains its freshness rt the Ebitor anb Staff uninvitedbut welcome guests, and its charm. Lucky devils, we and Podebrady is another.Also are, to have a hobby that always r 'Mist) Qou AU a 1bapp a huddle of amateurs, including opens up new vistas and fresh G6DL, G2AK,, G5J0, G6 AG, fields. G 6 B 0, G 2 D K,G 6 P L, I think 1936-37 will go down anb Mary Cbristinaz G 5 Q C, G 8 H W, and a lot of to history as the all -wave season. ,AigrAglicfigligfigAilegrzAg fz=figrzfmriLlioulzrrigligliguiti their pals. (" What makes me think so ?" v.fz Why this jolly lot should barge S.T.800 goodreasons !)But in in on " Medium Wave" I don't addition to the perfection of all -the -world corner, and well-he just vanishes round know.He doesn't seem to care, so let's reception our horizon is full of promise. the corner. pretend we are not interested.But it is Everywhere new stations are springing The police do not know who he is, but odd, all the same, don't you think ? up,fellowsarepractisingyo-ho-delling they know what he is ; a supreme example of and wisecracking, band -leaders are perfect- the man who believes in getting his radio on Very Confusing ing the timpani, pianos are being tuned, Easy Terms ! EVERYONE who has appreciated what a televisionettesare permingtheir hair, thundering good mimic Hubert is,is. announcers are gargling-all,all because What They Say ... Nosmo King's amusing radio appear- YOU, the radio audience, want the best THE London Regional announcer : . .. ances, will sympathise with Hubert's mother, that boodle can buy in the way of bright " Hereisa Newt !Er-here isa After the recent Belfast broadcast, for and breezy programmes. note on the new duties. . ." instance, Nosmo King rang up his wife in Let's have another on the strength of it. London to know how the show came over. Here's how ! Gerald Cock,DirectorofTelevision : (Continued overleaf.) vwx,rzfzu.1-zAagglisoigAm:ialigmt,z-Amm-AkszAcsoh-goimmusg,sa Avezzgoingarmlimgmura-rzmoigrz--rgALT4.I41.7mr A SPECIAL TELEVISION PRESENTATION APPEARS ON PAGE 333 IltiMMV,P7S1M--217;PM-7P,17,01,1=7.tollk7A701%7A P.17071-71MM-Ve-.17,-;-273%V.RANVV-Mg-,1-70V-V-7VVIV4 330 Popular Wireless, December 5t/t, 1936.

X-X.1Z tiCIZAS-ALIKAMIZSVAISEMAgSACAMAKfeitta,AMAC,47-14-AKSZ-UM:A.Z.AMU.AM'ACIZIZIWALTZWZ-14MIKALlia-fig-Alll' STUDIOS TO BE BUILT UNDERGROUND XWRBffikagM.....f4Ag.fit.VNI-X;r4i.AV.4:1-tilE&TAK.fgAkriC.-1`4==lifAgAgMAClik;VOICa-r,krAM.W.WAMAK. ..VA114.*M.f4MO: But after the good lady had been talking to Somebody has called the new B.B.C. Itemised Information her husband for some minutes she realised school of announcers " Narkover." Broad- it was really son Hubert, impersonating his casting House thinks this not quaite naice. COSTof radio time bought by political father. parties in American Presidential elec- So she told him off good and hard, * * despitehisindignantprotests.Finally tion estimated £400,000. the voice said, " I'll fetch Hubert to the 'phone, to prove it," and behold, Hubert SurpriseforBerlin! Mysterious hum at East Grinstead to be HOW quaintly cloth Memory, that great abolishedatcostof £320. Officially duly came on and asked, " What are you described as " 300 -cycle ripple from rectifier making all this fuss about ? " artist, colour the stuff of life. equipment."Unofficially described much His mother, to make sure there were really A moment ago I was sitting with more luridly. two people at the other end, then got them puckered and serious brow, thoughtfully * * * to speak together into the 'phone.Finally, pondering on the ware Mr. V. A. M. Bulow, who joined B.B.C. quite satisfied, she told her husband she a = -.:-.-&- i a week'sradio news, in 1923, has gone to Bagdad to take up was sorry ;to which he replied :" Oh, F_1111when I came upon ivw . appointmentinPostsandTelegraphs ---....rs the following item: that'sallright ! "-buthespokein v ie Department,ofIraq. Leftumbrella Hubert's voice ! She must have been quite i.- 1---ce, - " Experimental ..1.- behind, took topee. glad when the exchange cut them (or was it .: . exchange of radio him ?) off ! pictures between Trinity House saidto approve radio s I( \ Tokio and Berlin beacon idea for Tyne area. Would aid ships A New Broadcasting House Air.Av4., very successful." by leading them straight to river. , ...s ERLYA in the New Year the old Georgian And it suddenly * * * mansionsused by theB.B.C.as occurred to me that offices will be completely de -bricked, if the Japanese send Woodman,SpareThat Tree and plans for a great extension of Broad- to Berlin some of the pictures they showed ABAVARIAN woodcutter named Leon- casting House are me when I was out in Nagasaki-well, hard Schmid was swinging his axe 4oING DOWN nowundercon- Berlin would get its biggest surprise since and singing away one day when he sideration. The the Hitler clean-up ! was overheard by a music teacher who was effectwillbeto strolling in the double the size of A Good Friend woods. The music Broadcasting SOME of you chaps may find it difficult teacher was so im- House, and the to believe that I am interested in pressed by the work is expected to Quakers. (I know that " Romeo " woodcutter's yo-ho- takesomethree will, for he sent me a most un-Quakerlike de-!ar-ios that heun- years from now. postcard recently, about the " Smack in the dertook his musical One oddthing Eye For Poets " paragraph I wrote in our training, and now that has been stated November 7th, issue.)However, I ens the woodcutteris is that there will be no proyision for a interested in Quakers, and I occasionally often heard in the television studio in the new premises.This read " The Friend," which tells of their programmes of the does not worry me so much as another manifold activities. Munich station. His statement to the effect that the roof will In this (journal recently I saw it stated Mozart arias are particular favourites. be devoted to a staff restaurant, and There is,however, one minor the bulk of the building to offices, snag in thisso far truestory. the studios will be underground. The Munich station's masts are What, I ask you, will our pro- made of wood, and-well, you grammes be like if they emanate see the snag, don't you ?If the from a vault ?Will a sepulchral tenor gets a little absent-minded start ensure that snap, that quip, one day, when somebody has left that roguish, chase -me flippancy an axe lying about, the masts of for which we hope ?What a hope ! Munich may suddenly horizontalise their perpendicularity, amid a cloud Royal Radio of dust. Once a woodman, always iTwas stated recentlyin the a woodman ! 1 " Bradford Telegraphand Argus " that the Duke of Kent Linking the Air -Liners has bought a new radio set.It SEVEN years ago, when the first has three loudspeakers and more regular aeroplanes were link- than twenty valves. ingBritain with the Con- Young King Peter of Yugoslavia tinent, a passenger on one of the is an enthusiastic set -builder, who planes could not receive a radio - likes nothing better than a blue- telegramenroute. To -dayhe print, pair of pliers, and a screw- " What's a fella could do so, from the technical driver.He favours sub -baseboard to do when they point of view, though regulations situp halfthe wiring, and all the King's horses nightlistening forbid cluttering up the ether with and all the King's men have to to the short such messages.Italy, however, wait when a tricky bit of trimming waves? " has now thrown open her ground engages the royal attention. radio stations for " airadios "-as they are called-to any destination. Twiddly Bits thatthe name C. F. Jenkins,of New On Empire routes and where the ether Berlin has been experimentally broad- York (often bracketed with that of J. L. is not so congested the passenger in the air casting weather charts to pilots in the air. Baird as one of the pioneers of television), liner is as well placed as the passenger in * * * isthat of Charles Francis Jenkins, the the liner at sea-he is never out of touch. Chap at a Los Angeles exhibition plays American Friend whose inventive genius Soon this air -telegram service will be too about nightly with giant spark of 1,500,000 did much to make the modern cinemato- commonplace to mention.Yet only seven volts.Has no patience with listeners who graph projector possible. years ago it was one of the wonderful are nervous of leaving the juice on while He's been a true Friend to scientific Things to Come, fiddling with set ! entertainment. ARIEL Popular Wireless, December 5th, 1936. 331

you want to know about the B.B.C. It is always considered indiscreet to tell SoDance Orchestra and its work ? Well, a lady's age, but I may perhaps inform I think at this time of the year, such you that the combined ages of the Three a subject, interesting though it is to me, Sisters work out at an average of only might be a little dry to you.I propose, about twenty-three years. therefore, to tell you a few things about Who isthe big noise of the band ? the orchestra and our work at Christmas, Well,it depends exactly on what you and then to introduce you to some of the mean.If it is a matter of sheer noise, boys who you will hear over the air during perhaps I would put George Elrick down, or the festival season.Though you won't be Charlie Price, or perhaps Tony Thorpe, who able to Eee us, except perhaps a few of plays trombone.They each have their you who are getting television sets this moments. Christmas, the boys and myself and the IN AN Then in the saxophone section, we have Three Sisters, Molly, Marie and Mary, INTERVIEWour " giant," Bert Gillis.He 'plays the will be with you in spirit and in sound alto and baritone saxophone and the first during the Christmas holidays. clarinet and alto clarinet.I have known In our studio at Maida Vale, we shall be when you've been listening to him.But him for many years.He was with me at playing and singing into the microphone what you probablydidn't know was Gleneagles and has also had experience while you are sitting round the fireside that his early ambition was to be a doctor. during a long tour in South Africa. cracking nuts and jokes and playing the He went to Gordons College, Aberdeen, and usual Christmas jokes on Uncle Joe and there he started a dance band at the Single Stringers Auntie Bessie. college.The result is that he is not a I have mentioned that only five of the doctor but a very valuable member of the members of the band excepting the Three We'll Have Our Fun I B.B.C. Dance Orchestra. Sisters are single.It is a curious fact You can picture if you like the room that all those five are in the string section. with its white draperies, its three or four XMAtIMAigii-UaliMX.11t-OZAKAIVLAIWit There is Joe Hitchenor, Cyril Harling, and microphones and a great studio clock tick- Henry Hall introduces you to some Eric Cuthbertson-three fiddlers, with Cyril of the boys-and girls-of the B.B.C. also doubling oh the tenor sax. ing away the seconds as we broadcast. Dance Orchestra who will help to Well, there are at least twenty-five of us bring fun and good cheer to your Joe comes from Northampton, Cyril from in the studio, including the Three Sisters firesides this Christmas. Leeds, and Eric from Birmingham. Then and myself, and we shall be asked to give thereis Syd Williams to make up the you as much lively, seasonable music as we VligfaregAgIgOKAL-XUSCroffliCWAZIIIII He and Stuart Knussen can.There will be no holly or mistletoe I don't think you need any other intro- break the single record of the strings. or Christmas decorations about the studio, duction to Charlie Price, my first trumpet, Syd hails from Barry and plays the and those of us who are married and have Brecon born, than the photograph which he second violin.He is a keen Soccer player, children will, of course, not be able to take has sent for your article.I am glad to say with cricket and tennis as his summer partintheusualChristmasfestivities he doesn't bring his chum to the studio games.He was in the New Queen's Hall with those at home.But we shall picture with him.I think we might have a little Theatre Orchestra from 1926 to1928, our own families seated round their loud- bit of difficulty if he did. having been trained at the Royal Academy. speakers listening to us as you will be Incidentally, it may assist you in your Joe Hitchenor came to me straight from throughout the British Isles, and Trinity College, but Cyril Harling as others allover Europe and set out in life to be a schoolmaster. perhaps America will be listening. AN OFF -DUTY SNAP He found he liked dance -musics I have heard people say that it better, took it up and joined Sid is a shame that we should have Lipton.He came to me this year. to work on Christmas Day.I Most of theboysarekeen don't know that it is, for if you golfers, but they do not all reach knew the boys as well as I do, the expert stage that Eric Cuth- you would know that there will bertson has.He was the winner be no lack of gaiety during the of the Golf Championship of the B.B.C. Dance Orchestra broad- B.B.C. last year, and is runner-up cast this Christmas. this year.An excellent cricketer, too.As a matter of fact, all the His Hobby string section is good at games-a With George Elrick, drummer, peculiar thing when one considers Billy Smith, and Charlie Price, the delicate fingers they have to our second and first trumpet, to possess. say nothing of Freddy Mann, the third trumpet, there is no danger Our Cockney of things being dull in the studio. The fourth of the unmarrieds Freddy, in particular, is one of is Herby Powell, my viola player the biggest humorists in the band. from Barry, and number fiveis Freddy comes from Birmingham, Theo Farrar, who plays the double andhischief hobbyisthe bass. breedingof chows, which he Oneofthemostversatile exhibits at the Dog Show and membersof the band is Eddie particularly Crufts. A cheery glimpse of Bert Powell trying his hand at the " beer engine " Cromar. He has the most amazing The band is and always has as a change from playing the violin and viola in Henry Hall's orchestra. aptitude in the mastery of musical been British, and its members The bar, incidentally, is NOT at the B.B.C. instruments, and plays alto sax., come from all over the British baritone sax., clarinet, violin -and Isles.George Elrick, who plays the drums mental picture of the band and its make-up trumpet. and is one of the most popular comedy if I tell you that every member, with the Freddy Williams, our real Cockney, has vocalists on the airto -day, hails from exception of the Three Sisters and five of not only the second alto sax. to look after, Aberdeen.Perhaps you'venoticed,that the boys, is married. (Continued overleaf.) 33.2 Popular Wireless, December 5th, 1936. MY ORCHESTRA AT Then he started a dance band on his own in Cardiff. He played at Jimmy

CHRISTMAS Wilde's Palais de Danse and, as a matter (Continued from, previous pays.) of fact,broadcast with his band from Cardiff for two years. His instrument is the saxophone, and for butalsothesecondclarinet,whistle, some time after his Cardiff career he was ocarina, goofus, etc. with Debroy Somers.Later, he joined me. Of the careers of the members of the Talking about vocalists, let me tell you band, probably one -of the most interesting about the Three Sisters-Mary, Molly and is that of Dan Donovan, the vocalist you Marie. The first two were among Cochrane's hear so often. He first set out in life in a Young Ladies. Marie was trained as a shipbroker's office. Perhaps, as he was singer and dancer, and Molly met the other

Tf.MV'-fg-M-MAM',fMN=gk!:a'k.AM-AtgtMgtigMfitACSCN XX' Agfa Xu'rgg WHO'S WHO IN THE ORCHESTRA. HENRY HA LL F. BURTON GILLIS Soprano, alto and baritone saxophone. r. E. CROMAR Alto saxophone, baritone saxophone, clarinet, violin and trumpet. ERIC CUT H BERTSO N Violin and viola. DAN DONOVAN Vocalist and saxophone. GEORGE DICKINSON Guitar. GEORGE ELRICK Drummer and vocalist. T. FARRAR String bass. JACK HALSALL Tenor saxophone, clarinet, flute. J. H ITCH E N OR Violinist. CYRIL HARLI NG Violin. S. KN USSEN 'Cello. F.MANN Trumpet. HERBERT POWELL Violin and viola, A CHARLES PRICE Trumpeter. A An unconventional photograph of Charles Price, N BERT READ . Pianist. first trumpeter, in Henry Hall's orchestra. '0 BILLIE SMITH Trumpet. 0 ERIC TAN N Trombone. piano for the silentcinema.Then ho 0 TO NY TH ORPE Trombone.. took up dance musicin 1925, and later FREDDIE WELSH 4.4 Trombone. joined Roy Fox. FREDDY WILLIAMS Alto and bass saxophone. It is perhaps strange to the uninitiated S. WILLIAMS 0 Violin. that so many crack dance -band instru- In addition to Dan Donovan and George Elrick, the vocalists include The Three Sisters.it mentalists start life as " straight " musi- $ k cians.But a classical musical education is tworensv-s-n-n-nmtm,nnlig-nme...vmen-n-vwxvIrmitos-pspos a very fine grounding, and many of my boys have been trained asclassicalplayers. born in Cardiff, thoughhis,parents were two " sisters " in a show at Drury Lane. But it is not often that one finds a player Irish, it was only natural.But he soon After the show ended they stuck together like Stuart Knussen, who has had fifteen tired of that and, against his parents' and did some film work. years' experience with the Halle Orchestra wishes, he set out to become an engineer. One day they found themselves in a under Sir Hamilton Harty, and yet has for- He did, in fact, qualify as a motor engineer. scene in my film, " Music Hath Charms." saken it to come into a dance orchestra. Iheardthemand Stuart played first'cello in the Halle "MUSIC MAKERS" ALL thoughtthey were for four years, and is now 'cello player with pretty good, but as I me. He comes from Cardiff, and left tho had nothing to offer Halle to come to the B.B.C. dance orchestra. them at the time, I said nothing about it. I Hold the Record Later, whenIwas One of the voices you hear over the air looking for a trio, I sometimes in the vocal triosis that of got into touch with Jack Halsall.He is my tenor saxophone them, and they are player, and also takes the third clarinet. now among my regular Jack has had plenty of practice in hotels singers. round Blackpool, and with Howard Baker Molly is the leader in Liverpool. Later, he went to Billy of the trio, Mary is Cotton, and eventually joined the B.B.C.

a blonde and Marie a The band is one of the most cheerful brunette. They come, bands in existence. They are probably the respectively, from hardest worked, too.We do something Kent, Hampshire and like four hundred broadcasts a year, and Wales. goodnessknowshow manyrecording In addition to George sessions and rehearsals. Elrick, another "Scot- I think that, as a matter of fact, in the ty "in the band is five years in which I have been directing Freddy Welsh. He the dance orchestra I hold the record for plays the third trom- the number of broLicasts in this part of bone and doubles on the globe. We are, undoubtedly, the most the bandoneon. He often heard broadcasters in Europe. comes of a family of EvenduringChristmaswedonot trombonists, both his rest, as you will see by your programmes. grandfather andhis -We - shall be on the air on Christmas Eve, great-grandfather ChristmasDay,Boxing Day,andon playingthatinstru- New Year's Eve and New Year's Day. ment. Freddy started Pretty good going, but we don't mind. in the musical world There is no lack of fun and festival spirit inhishome town, intheMaidaValestudioonsuch A merry group, featuring Henry Hall, the Three Sisters, and Ber Glasgow, playing the occasions. Popular Wireless, December 5th, 1936. 333

334 Popular Wireless, December 5th, 1936.

On the rightis the famous television pioneer, John Logie Baird, with some of 'Ms early apparatus, while below he is again seen, this time televising Sir Oliver. Lodge.

A scene in the Baird studio duringthefirsttelevision broadcast.

To the left, below, is a group looking at a 30 -line receiver, whiletothe rightisascene from theB.B.C.'soil 30 -line studio.

Popular Wireless, December 5th, 1936. 33

WHEN one switches off a television loudspeaker.How muchintermsof outfit at the end of an all -too -brief WORLD'S FIRST retailprices ?Six pounds for a pretty hour of the new service to change good one ? over to the ordinary broadcasting pro- A vision receiver is needed.No. L.F. grammes, the effect is devastating. TELEVISION power,noloudspeaker.Four pounds ? The radio has gone blind and become Cathode-ray tube ?Let us say £4 and once again just sounds and voices from be generous.Time base ?(one multi - behind a dark, impenetrable wall. SERVICE grid valve and two amplifiers in the not It is like walking from a sun -lit garden very distant future) ;call it £5.And add into a totally unlit room. one pound for tying them together. It is obvious that television is the new There's your £20 complete television set. broadcasting and will ultimately completely For a time television willbe the rich man'spleasure. That won't lastlong. And within five years they'll be on the replace blind radio just as the talkies have market at £12 or £15 ?Before seven years completely replaced the silent film. Prices will soon begin to fall. Many thingswillcontributetothe have elapsed you'll see adverts. for cheaper It has made a start, and technically it is ones even than that. superior to sound broadcasting as this was cheapening of television sets.First of all, valuablestabilisationof For the moment heavy initial research inthebeginning.Farsuperior.The you have the pictures are amazingly bright and detailed. transmission technique which the Advisory and development charges have to be levelled As good as iu the best cinemas. Committee is enforcing. Not Everyone seeing the new television for the for a period of at least two yearswilltherebe any first timeisimmensely thrilled,forits THE "PICTURE PAGE" GIRL entertainment value is complete. changes made in the B.B.C. transmitterswhichcould Programme Hours and Cost render obsolete a set bought to -day. But at the moment television is limited So the radio industry can in programme hours, and it is expensive. go ahead on mass -produc- It would be strange if this were not the tion with no fear that their case.Everything has to have a beginning, plansmight havetobe and the remarkable thing about television changed at a moment's is that it has begun at such au advanced notice and new models pro- point. duced. Think of the early motor -car.It cost And you know how prices £500 or more in its very cheapest form and fall once there can be organ- it gave indifferent service. ised mass production. Itwassupposedtotransportyou mechanically along the road from one point Competition Will Help to another, but it so frequently failed that Then there will be com- a popular song calledGet Out and Get mercial competition to help. Under " achieved an immense success, and Already a dozen firms are Harry Tate sprang into fame by giving in the field making televi- music -hall skits on that method sionsets. Therewillbe many others.A scramble motion. This is Joan Miller. who appears on the screen between items of "Picture No doubt railway chiefs used to smile at to grab the plums of this Page," one of the most popular of the television programmes. the idea that the motor -car would ever brand-new trade is certain become a really serious rival to the rail- to take place. road.More to the point, drivers of horse- And the " looker " is going to benefit. against small sales ;mass production has drawn carriages scoffed loudly. " Wouldn't it be possible to make a tele- not yet commenced.But the wheels have But wherearcthesescoffersnow ? vision set for £20 providing you entered begun toturn.They willsoon gather The answer is that thOse who arc still able into big -scale production ? "asked a big momentum. to work arethemselvesdriving motor man in the electrical industry the other day. And then television as a vital new form vehicles ! The answer is, yes, providing the scale of home entertainment will be in its stride. Television has a tremendous start in that were big enough.And in due course it will Who will there be who, having eyes, will not its results are comparable with the modern be.Take the component parts item for want to see ?To peep into the outside car.There remains only the question of item.You want a sound receiver plus world, to enter without effort into centres price and programme of sport and entertainment hours.The latter are in while yet remaining com- the hands of the Television IN THE ALEXANDRA PALACEGROUNDS fortably in an armchair at Advisory Committee and home ? the B.B.C. It Has Arrived Rapid Progress Television ! Dream of Spokesmen of both have the prophetically minded declared that there must novelist for countless years ! and will be rapid progress It is here now.One of the both in numbers of hours Shapes of Things to Come of programme andarea no longer lies in the future. availability.A quarter of It has arrived. thepopulationofthis There are plenty of people country is now served with to deride this new thing. television.Provincial There always are. Sonic stations willstart to be aremerelyold-fashioned erected during 1937. reactionaries, the kind of Price ? The cheapest folk who won'tridein outfit on the market is 85 motor -cars because they are guineas. A lot of money ! new -f angled."Others are But it is not an exorbitant inspired in their depreca- priceinviewofwhat tion.They fear television television can bring you. for one reason or another. However, only a com- Thentherearethe paratively few will be able sceptics who are sceptical throughsheerlack of to pay as much even on Many good outdoor programme items have originated in the grounds of Alexandra theeasywayprinciple. Palace.Here is Archie Compston demonstrating golf shots. (Please turn to page 337.) 339 Popular Wireless, December5th, 1936. D Apart From England and America, many other countries are conducting tests and experiments in television, and the pictures on this page indicate the stages of development attained.Considerable advances have been mLde in Germany where the Olympic games in Berlin were televised this year. connection Public viewing halls were thrown open to the public -so that those who were unable to attend the games could see them on the television screen.

Obj _frOjP"Z0, !Wk. pkizieh "ll g : tilep A 4604gefe 2..at i.10Nati be of el P110.°e ig4t '14001,9,442°44r0e°,,°440 i. Pie Imo co left '00,14, .OeeoeNez. 17.104, . 4:14.-:,'6. thi'' It 161. gO0248 ty,, 4. . 8eel.8 Yeae.1. Ofd ie tile Oe'. vei7 .,-0 of e4de '144"g 02 4:20 . ede th-914'itte IVotc4etZe Af e":44- 57)0%1 Qic4'07;.1:49,,;17/1;:-.: .4 2k64:4toil44%1421°14Zlilik'1;i2$val_. * isCo to:0242/Vete * For then .44.4e.nd in . et oi thebe sectselleed 14' ',it) ,. .1020, tett . 414 I1 4,2d 'Y A toQ4' at theeV to 4, °41"?p,Pel P-qr.,. 424,, bait_ k.41. oe4f10°2P 4:bis-' 01 tl :1'd P gap e 4 that4;248 a021Pei 0004a ho ''' IP e e00 4 de `he2'112,/ Ps his of .Pi , a, I e 0041,2 th, I,.,1022, `' * t ,a,,,.e... a'ktitbee°P 'ioove,,,, a itizi tio en * goe , 4" `-', 4P4,rielie 1, e ,2,2,1 i,. lalitee-e -, 0, * d 4,lio GERMANY -JAPAN e* ITALY AND HOLLAND Popular Wireless, December 5th, 1936. 337

of thing has been purchased. WORLD'S FIRST -This van is able to go almost TELEVISION SERVICE anywhere and sendits pictures back via the ultra - (Continued froon page 335.) short waves just as can the ordinary O.B. vans for blind imagination (they cannot appreciate the broadcasting. immense potentialities oftelevision) ;or Films taken anywhere in ignorance (they haven't seen what it can do). the world can subsequently Or maybe they remember the ballyhoo besentover theairto which accompanied the B.B.C.'s abortive " lookers." 30 -line experiments. In truth is television the This new television has no connection eyes of radio. with that unhappy debacle.If any of you still think of television in terms of shape- Remember These Facts less,flickering -blobs and splashes, you Now just let us see should at once start thinking again. exactly howfartelevision Let us try to give you something of an as anationalservicehas idea of what it actually is like. advanced. The stationat Turn to a really large newspaper illus- Alexandra Palace isinfull tration, one nearly a foot square, and think programme operation.It is of this as suddenly springing into, life but important to note that the withsomewhatbetterdefinitionand transmissionsarenotex- certainly much brighter.Then imagine perimental. that it is, into the bargain, a talking as well But they will be extended as a moving picture. in That is television. in scope and increased durationinthecourseof You Must SeeIt time. MR. LESLIE MITCHELL, the television announcer at Alexandra Imagine you are sitting in the back row A special cable has been Palace. laid to Broadcasting House so of a super -cinema, but that the pictures how there could be.As we have said, you see are simultaneous representations that programme items could be originated thereif desired. television begins at a point in technical of actual events. development where most other new things That is television. Also a television cable has been laid Think of the radio stars coming right between London and Birthingham, and leave off. this is being extended to Manchester. That is why it is bound to grow quickly into your own home so clearly that you and soon. The day when television will can count their eyelashes. The B.B.C. has said itisn't going to In be in every home is not so far away. That is television. rush the erection of other stations. Great Britain has the very first television In part. thisitiswise. A great dealisbeing service in the world. Why is it we have For a full appreciation of its capabilities learnt every day from the operation of beaten our friends across the Atlantic in and possibilities you must see the real the A.P. transmitters, but new stations this new thing ? thing itself. will almost certainly be built during 1937. Anditwillthen There are two reasons.In thefirst merely be a matter place, our broadcasting is in the hands of IN THE MARCON/-E.M.I.STUDIO of duplicating appar- one central authority.In the U.S. there atus.The engineers are numerous competitive concerns and it will never again be isn't a simple matter for any of these to faced with the pioneer- embarkonanentirelyrevolutionary i n g difficultiesen. development. countered during the More important still there are technical earlier months of this advantages on one side.The population of year. Great Britain tends to mass in and around definedcentres. Wearecompactly Two Outfits planted !And our towns are not composed AtAlexandra ofgreatskyscrapers.Theultra -short Palace there are two wave such as is used for the new television is separatetransmitter given a chance to seep over large areas outfits. Oneis a without meeting with obstruction. Marconi - E.M.I. and There will be those who will resent the theotheraBaird. money being spent by the B.B.C. on the Theyareusedon televisionservice.Alreadymurmurings alternate weeks. are to be heard. Some are saying " Why Much has been said should a part of the fees paid by ordinary as to the complica- listeners be used for television ?' tions to receivers The answer is that television will be for whichthis arrange- ordinarylisteners.Itwillsoon be the ment causes, but greatly improved ordinary broadcasting. most of these observa- The broadcasting of to -morrow that wiil A rehearsal of the Griffin Brothers' comedy horse, " Pogo," and Miss Lutie. tionsaregreatly not be blind. exaggerated. The most remarkable aspect of it is that The " viewer ". can change his set over A Sound Propheq even at this moment the B.B.C. is able to from the one tothe other merely by Five years ago POPULAR WIRELESS was do wonders for the handful of lookers " operatingasimple switchwhichalso, almost alonein saying that the early, that exists. in some cases, controls the change over purely mechanical methods of those days News reels can be transmitted.Studio from the television wave to the ordinary could lead us only a little way along the shots dissolving from long shots to close- broadcasting band. path of progress, and that something new ups with uncanny smoothness are possible No great complexity in the design is andrevolutionarywasneededbefore and are being done.The marvellous tele- caused by this, for it is merely a method of television for all could become an accom- vision camera can be taken into the open an additional lead or two and, perhaps, an plished fact. air to collect a thousand and one interest- extra fixed condenser. High -definition systems on ultra -short ing items for immediate reproduction on Another important point.There will be waves as at present used incorporate the the home screen. nofundamentalchangeintelevision required revolutionary ideas.The Eyes of A £20,000 television van for doing this sort reception for some years.It is hard to see Radio have arrived. 338 Popular Wireless, December 5th, 1936. VisiouProrames ice°Already there is a large number of different types and makes of television receivers on the market.Some of the instruments which are available are illustrated on this page.

Abovoisagroup ofpeople lookingata MickeyMouse filmon a " Televisor " receiving set.On the extremeleftis a Marconiphone Model 702 instrument, while that in the centre of the page is the G.E.C. televisionreceiverandall -waveset. BelowistheH.M.V.Model900. This is a five waveband receiver which covers the ordinary medium-, long-, andshort-wavebroadcastingin addition to television sound and vision. A model for television only isalsoavailable.

A chassis view of a Cossor television receiver. Popular Wireless, December 5th, 1936. 339 TELEVISION TOPICS-Collected by A. S. Clark 0;nnw,r,--nm3triV20-NACVSN.75%.**1.-AZ-V*M3V-MPOPY',41, These classes, which use of an ordinary broadcast -type aerial. are to cover practical gTechnicalities, Personalities and News from all parts of.1 But don't let matters rest there. the World make this "Popular Wireless " feature the" and theoretical work, The location of the aerial can have a finest medium by which readers can keep right in touch5 are an indication of tremendous effect on its pick-up, especially Lo: with all aspects of development in television. the growing need for if itis being used indoors.There is, for properlytrained instance, the question of whether to use the ,%,;:ffig_mmfialTigwmfit,Ag..uxmligulextwz,,,Kwja%0A people intelevision di -pole vertically or horizontally, and the work.In America it nearness of various surrounding objects is confidently expected that television will can have a big effect. " TELEFRAMES" provide careers for many thousands soon And don't forget to try different types after its inception as a public service. of special aerials, half -wave di -pole, half - Items of general interest * * * wavesingle -polewith dummyfeeder, and so on. LOOKING -IN PARTIES WE have received a letter from a reader residing in Belfast. He says he has A member of the G.E.C. research staff has been giving television parties in north- DEMONSTRATIONS IN " N.18 received the sound programmes sent The firm The Teleradio Company of 157, out withthevision programmes from west London recently. He used a standard The distance appears G.E.C. receiver, and the object was to Fore Street, London, N.18,iscreating Alexandra Palace. experiment on receiving conditions in the considerable interest in that locality with to be a little over 300 miles, which is good Garden Suburb of Northway. its demonstrations of a Pye " Teleeeiver." going for " optical " waves. Visitors, both young and old, were asked Among the distinguished local people We wonder whether this is the record for their opinions.Generally they were who have " looked -in "are the Mayor, distancefor" Ally -Pally " reception, or very impressed and greatly enjoyed the Mayoress, and Aldermen of Tottenham. whether anyone else can beat it ! programmes. Immediately after their visitthe Town Reception was consistently good and was Hall was offered for the use of the demon- free from motor -car interference.The use strators at a very nominal fee. A NEW VALVE of a rotary converter on the D.C. mains was The proprietor of an important local A new valve capable of giving good entirely satisfactory. hotel also offered his hall for demonstrations once a week after paying " Teleradio " a amplification on ultra -short waves has been * * developed in America.It is a push-pull * visit. power pentode, presumably intended for EXPERIMENT A LITTLE The public are invited to leave their transmitting,but no doubttheideas When you first try a special television names at the various branches of the involved will eventually be adapted for aerial you will most likely be very surprised Teleradio Company for invitations to be receiving types. at the improvement in reception over the posted to them. Common screen and suppression grids are employed for the two pentodes, which THE ORIGINAL CATHODE-RAY TUBE RECEIVER are in the same glass envelope.Complete shielding between input and output circuits is provided. * * * TELEVISION CLASSES Another item from America concerns the inauguration of television classes by the New York Y.M.C.A. Schools.

migimmAtilimatigiamiumwiugAm ELECTRON CAMERAS 0, A general view of the first cathode-ray tube receiver used in this country, showing what the various units do and the purposes of the controls.It is interesting to note that this receiver was developed and employed in mmrwarm-s-],w`-A the " Popular Wireless " Research Laboratories. THERE are two formsofso-called " electron camera " which work on of the light. We thus have a whole collec- In this wall, which is really an anode, is different basic principles, and as they tion of small charged condensers repre- a small hole, allowing the electrons at this are often confused with one another ansenting the light and dark components of particular spot to pass through on to a explanation of their differences should be the picture. collector." The current flowing from this of some value.One ofthemisthe The next step is to provide a beam of " collector " will vary with the strength Zworykin " Iconoscope," and the other electrons which will pass over the photo- of the light on the spot of the picture the Farnsworth " Dissector Tube." They sensitiveplate in the normal scanning opposite it. bothoriginatedinAmerica andthe method of line by line.This beam is, of All we have to do now is to supply the " Iconoscope " is the principle on which the course, conductive, and the cathode from scanning.This is achieved by moving ;the Marconi-E.M.I." Emitron " camerasat which it originatesisconnected to the electronic picture emitted from the photo- Alexandra Palace are based. metal plate behind the charged particles. sensitive plate as a whole. As the beam passes, therefore, the small The " Iconescope " condensers will be discharged by currents The Two Forms First we will consider the " Iconoscope." flowing through the circuit joining it to the Thisisachieved electrically, andin The picture or scene to be televised is metal plate. These currents vary with the effect moves the picture line by line past focused on to a plate situatedin an degree of picture light, and can be made to the hole in the anode so that each little evacuated tube.The plate consists of a provide corresponding voltage variations section has its turn of passing through the sheet of metal covered with a sheet of mica by being passed through a resistance. holeinthe anode andaffectingthe on which isa layer of photo -sensitive In the case ofthe.Farnsworth tube the " collector." material made up of smallinsulated picture is also first of all focused on to a The " Iconoscope "has a stationary particles. photo -electric screen.But thereafter the picture and a moving scanning device as The light focused on to this material actionvaries. In this instrument the distinct from the Farnsworth "Dissector causes the release of electrons which build electrons are allowed to radiate from the Tube " which has a stationary scanner up charges on the particles, in relation to screen, being electrically focused on an in relation to which the picture itself is the metal plate according to the strength opposite wall. moved. 310 Popular Wireless, December 5th, 1936.

adjusted so that the condenser will discharge at a given point, but it TELEVISION TOPICS Continued may happen that this discharge the scanning circuit described rogismamagm-sumommimisimmulammifigtowsi# point will occur later than the 1Flast week were connected to a end of the line transmitted.This tube and by some lucky chance is where the synchronising signal we hit the right speed on both mkt TELEVISION FOR BEGINNERS comes in.The impulse is fed to picture and line first go off, we the grid of the relay, and at the In which Q. Stevens describes the use of synchronising end ofthetransmittedlinea should get a picture on the screen sudden kick is given to the grid if the -transmission was on.The itr,'PAIMMINAM-7.$74M7g-VV-V1r--2'..;MVP.IN-311:51:-MVPOMPIM right speed of scan is only a matter bias which causes the discharge of adjusting the controls carefully currenttostart. (Youwill remember that in a gas -filled relay so that we get 240 lines and 25 mitteritself,which provides ato start up again at the com-the current does not start until pictures per second (for Baird). definite pulse both at the end of mencement of the next line.It the voltageon the anode has Fluctuation Effects each line and each picture.The is these breaks in the carrier wave climbed to a certain value.)The television signal really consists of which provide the synchronising In practice, however, we should effect ofthe synchronising im- two parts.During the scanning impulse which is applied to the pulseisthus to discharge the find that after a few seconds the of a line by the transmitting gear scanning circuittocontrol thecondenser at the end of the line picture would suddenly dissolve theradiofrequencywaveis length of line. into a series of irregular patches, transmitted whether itis ready modulated by the light impulses, Without going into too great or not. and we could not bring it back to and these alter the magnitude of detail at the moment, the action a coherent scene unless we altered A similar impulse is applied to the carrier wave in exactly the islikethis :Suppose the con- the grid of the picture frequency the controls again.The reason same way assoundimpulses denser of the scanning circuit is for this is that the least fluctuation modulate the wave in ordinary charging slowly, the voltage risingrelay every 240 lines (or 405) and or disturbance in the scanningbroadcasting. At the end of each across it as the beam is deflected the picture is completed at the circuit will alter its speed tem- line, however, the carrier wave is across the screen. same time as that transmitted. porarily and may make it run cut off completely for a moment, The grid bias of the relay is Looking at it another way, the faster or slower than the trans- scanning circuitreally provides mitter.Then the light and dark the lines as nearly accurate as patches would occur in the wrong THE SOUND TRANSMITTER AT "A.P." possible, and the synchronisint, places and we should get a nasty impulsetrimsthemupand looking blur.To show how small holdstheminstep withthe a disturbance can affect the pic- transmitter. ture, suppose the voltage of the mains rose slightly for only 1/4th A Clever Trick second-such as might happen if There is another clever trick a lamp were switched off. The which the synchronising impulse volts across the scanning circuit does at the same time. When the would rise to correspond and the beam has moved across the screen lines would momentarily lengthen. it flicks back again to the start, Noweachlineis occupying andthisreturn movementis 1/6,000th second in the drawing, so sometimes visible as a faint line in 1/4th second we should complete on the screen.To avoid spoiling 1,500lines,ormorethan6 the appearance of the picture this complete pictures ! returnlineissuppressedalto- gether by applying the synchronis- Locking ing impulse to the grid of the To preventthisdisturbance cathode-ray tube itself as well as frominterruptingthesmooth to the scanning circuit.Then the running of the circuit we have to beam is cut off at the end of each provide some means of locking the line and the return journey is not scanning linesto thoseof the visible.The beam goes back in transmittersothattheyrun the dark, so to speak, and re- " synchronously," i.e. exactly in appears to light up the screen step, both in length and in timing. whereitstartedfrom.Well, This is done very cleverly in the This istheB.B.C. transmitter at Alexandra Palace which broadcasts the sound that's all for this week.I hope signal sent out from the trans- accompaniment to the vision programmes. I have made myself clear.

Il VAMPAKAMM-M'flaWaWitrilfiMIMAg AC'44%Mfil.$15.151-NO sure, the plucky long - I think that the film strips were an inspira- sustainedeffortof tion. They were probably borrowed from the Mr. Eustace Robb Pabst film " West Front."The chief point SEEN ON THE AIR with low -definition about this production is that it was made News and Views on the Television Programmes by programmes. I think for television.It may be hailed as the first it a great pity that intelligentandintelligibletelevisionplay, our special radio -screen correspondent, L. Marslancl some of the lessons William Devlin as "The Tiger" was great. 0 Gander of those thirty - line programmes have to "Fisherman's Fortune " :t1g7.4,'1%107010103g2g.V-714-1MN-7MMMIW...,---VM-MIPSNAMA be learned now over Now to come to less agreeable subjects: again. The week under review started with one ANOTHER week of television has brought I should possibly be more vitriolic than I of the Movietone Magic Carpet films, " Fisher- me the conviction that unless there- is am, but it happens that just before I began man's Fortune," which I found of moderate speedy and definiteimprovement in to write this article I saw a programme which interest only.This particular film is one programmematerialseriousdamagewill really did show some sings of grace.It was a presumably not aiming at great commercial be done to television prospects.In brief; the potted versionof" The Tiger,"Reginald success, but depending for its merit on fine position is that the technicians have succeeded Berkeley's play from the Embassy, dealing photography. Apparentlyitistherefore and the programme compilers have failed. with the life of Clemenceau, ." The Tiger." good enough fortelevision." But fine Dealers declare that while they have no This was a new departure in the series " From photography must be seen through an ideal fault whatever to find with the apparatus of the London Theatre." medium. The seascapes, the tumbling wastes reception, poor and unsuitable programmes of water, the swirling clouds of gulls, the are killing interest from a purchasing point Introducing Film Strips lonely trawlers-fine, yes, but not for tele- of view. It did notliftincomprehensible chunks vision. Yet with ineptitude, which I can only In apology for the B.B.C., it may be said from the stage play as was done in some describe as extraordinary, this film was shown that though for fifty years scientists have previous efforts in this series.The producer four times during the week. striven to wrest from nature the secret of recognised the boundaries of his medium and The next film shown in this particular week, television, and many thousands of pounds also its possibilities.He worked in close-ups " The Land of the Nile," moved with in- have been spent on research, hardly a thought in the studio and then very successfully intro- escapable logic from the sea to the desert has been given to the programme problem. duced some illustrative strips of film when the to be asdry.as its predecessor had been I say hardly a thought, but there was, to be play reached its war -time action. (Please turn to page 350.) Popular Wireless, December 5th, 1936. 341

RADIO BEACONS Wireless plays a very big part in the safety of ships at sea, and one of the most important developments inrecent yearsisthe radiolighthouse, or beacon. Below you are told some highly interesting facts about this valuable aid to mariners

By CAPTAIN J. G. BISSET, R.D., R.N.R. (retd.)

RADIO beaconsanddirection -finding the direction ofan wireless constitute the most valuable enemy ship or fleet aidstosafenavigationsince the using wirelesscould invention of the compass over two thousand be instantly located. years ago. After the war the In pre -wireless days, navigators were instrument known as entirely dependent on lighthouses, lightships the " direction finder" and fog signals to keep them from running (D.F.) was perfected on the numerous rocks and shoals that and came into com- bestrew the coastlines of the world.Such mercial use at many aids to navigation were-and still are- coastal stations. entirely efficient until the demon fog casts Inthosedaysa his clammy blanket over the sea.Then ship requiring a bear- powerful lights with normal rangesof ing had to call up the twentymilesor more are reducedin station and ask for visibility to less than two hundred yards it.When the station and become practically useless. was ready, the ship A ship's direction finder.Note the handwheel for moving the loop aerial. would send a series which is on the deck above, and the gyroscopic compass for reading the Sound Signals Not Reliable of dots anddashes bearings. Fog signals such as horns, explosives, and over a period of two bells are then brought into operation, but minutes, during which time the station All ships of any consequence carry a D.F. such sound signals are notoriously fickle in would determine her direction by the D.F. instrument to -day and the illustration shows range and radius over water, and the wise instrument and send it to her.This was a a typical model.It is about the size of an shipmaster places little reliance on them. clumsy procedure that had to be gone ordinary home receiving set and has a com- Wireless was first installed on ships in an through separately for each ship and it pass attached.Connected with it is a pole experimental way about 1902.In a few causedendlessdelayandcongestion, supporting a small loop -aerial which can years it became general and navigators who especially during foggy weather. be moved around in azimuth by means of a Thisdifficultywas wheel similar to the steering wheel of a car. FINDING THE SHIP'S POSITION overcomebyfitting When a bearing is required, the officer D.E. in the ships them- listens in through headphones till he picks 62 selves sothat they up the beacon signal, then moves the aerial could take their own slowly round till he achieves a complete bearings at any time. En fade-out, when a pointer on the compass gcrhioluse` Then came the in- card indicates the exact compass bearing. (i:-.wy./d/es) troduction ofradio beacons, hundreds of Taking Two or Three Bearings which are now dotted In this manner bearings may be taken of round the coastlines of two or three beacons in rapid succession. ------()A ack allcivilisedcountries. The bearing lines are then laid on the chart 70 They might almost be and their point of intersection represents Chczrzi-ze-G. calledradiolight- the ship's position. ure"r..reei houses,fortheyare Itisreally not quite as simple as it mostly erected in close sounds, because there are corrections to be 66 proximity to existing applied due to the curvature of the earth lighthouses, and during and errors in the compass, but an expert fogtheradio beam navigator has these things at his finger -ends 66- 68 penetrates wherethe and finds no difficulty. light cannot.But the There is no doubt that the introduction of -arhaIZZ beacon does more than radio beacons and direction -finding wireless has saved many a shipmaster from going This is a portion of a chart, the circles indicating radio beacons.It shows that, for it can be heard how easy itis for a ship to get an accurate bearing.In this instance at ranges of one hun- prematurely grey with anxiety when making bearings are being taken from three points, viz.: the beacons at Bishop Rock, miles the land in thick weather. Ushant, and Casquets. dred or more andisuseful during could hear messages being flashed from daylight or darkness. ADVERTISER'S CORRECTION. various coastal stations began to yearn for Each beacon has its own distinctive call - We have been asked by Messrs. New some invention that would indicate the sign and works automatically.In fine Times Sales Co., Ltd., to inform readers that exact compass direction, or bearing of the weather they operate for a few minutes in their advertisement of November 21st, wireless waves, and so enable them to every hour to enable ships to test their the price of their " Straight Three " was determine their ship's position. instruments. During fogtheyoperate given as 35/- including cabinet and valves Scientists tackled this problem, and urged every three or four minutes, the times being only.This price, however, also includes on by Admiralty requirements during the arranged for certain geographical groups so the speaker, but not the batteries necessary war they produced an instrument whereby that they do not interfere with one another. for this receiver. 312 Popular Wireless, December 5th, 1938. ON THE SHORT WAVES (but not literally) and use a triode for his first L.F. stage ;and I recommend any screened -grid valve as the buffer.There's no advantage in using a pentode. Here's a nice story for you.G. M. M. (on a hospital ship) built my " Short -Wave One " in December, 1932.Since then it has travelled 200,000 miles and never let W. 1... S. Replies to Correspondents him down !Furthermore, it caught on so badly that it now has seven " brothers " at for the 1937 B.E.R.U. THERE'S been a big run on " Verified sea. y The total mileage covered by this REGULATIONSContest are now published. As usual, AllContinents "certificateslately, family of babies would reach astronomical the contest will occupy the four week- dimensions ! ends of February, the Senior Contest taking and the postbag has contained more place on February fith-7th and 13th -14th, QSL cards than interesting correspondence. A Portable -Set Query I have been looking them over very care- and the Junior on February 20th -21st G. M. M. is interested in my portable and and 27th -28th. ' fully, and have been struck by one or two rather wants to make it, but also wants to The power limit for the Senior Contest is facts.First, it is extremely rare to find a introduce several modifications. batch of twelve cards that does not include Ican't 250 watts and for the Junior 25 watts. The our friend the Kookaburra from Sydney, quite see how to do them without turning times of working are from 19.00 G.M.T. on V K 2 M E. it into quite a different set, so I suggest the Saturdaytill19.00 G.M.T. on the that he either makes it as it is or sticks to Sunday forthe" Seniors,"whilethe Secondly, more than half the applicants his " one -valve wonder." Juniors " will work from 21.00 till 21.00 for the certificate send for their two African T. S. (Liverpool) supplies a lot of interest- each week -end of their contest. " yeti's "thecardsofS U 1 K G and ing news.He tells me that he heard an As in previous years, a Reception Contest S U 1 8 G, the well-known Egyptian ama- amateur transmitter speaking very highly teurs.This is not surprising, for they must is run concurrently with the transmitting be the easiest African stations to receive. of " P.W." over the air one morning, saying events, but will occupy only the first and that he had copy Number One ! third week-ends---i.e.thefirst week -end But I am told that S U 1 K G has issued a of the Senior and the first week -end of the proclamation that he won't QSL any more, Junior Contests.Since this is only open to as he's getting too many reports.(Is it UNUSUAL CONNECTIONS members of R.S.G.B., there is no point in true what they say about Egypt ?) stating the rules in fulL Varied South American Cards Plenty of D.X. About Thirdly, a weird and wonderful collection Readers will find, however, that there is of cards represents South America. As a decidedly abnormal amount of DX on opposed to those from Africa and Australia, the air while the contests are running, and I don't think I have seen the same South they are well advised to do plenty of American card more than once,And why listening. do all the Brazilian stations fill in, in the All the amateur wavebands will be used, remarks " space, " Brazil has (or ' have') and there is no doubt that many contacts the best coffee of the world " ?It may be with South Africa, Australia, and New true, I mean, and all that, but why rub it Zealand will be made on the 10 -metre band. into the radio racket ? Speaking of 10 metres, I may as well V. H. T. (Londonderry), in applying for mention that it has had several" off " his certificate, asks me to publish a list of periods during the last few weeks.One or stations he has received, " in order to dispel two days have seen a completely dead band, the fallacy of all Londonderry listeners that and many others have been extremely poor. this is a bad hole for distant listening." The The consistent conditions that prevailed trouble is that I can't-there are far too during September and October were not many of them. maintained during November, although, in All his listening is done with my " stan- The cathode coil in this case being wound on the same former spasms, DX was extraordinarily good. dard -baseboard " layout of detector and as the grid winding.Note the variations in the It seems as though the 20 -metre band is separate oscillator, to which he has added reaction connections as compared with the normal destined to carry the greater part of the a resistance -coupled stage. He goes up the ones for a four -pin coil. " DX traffic " for a long time to come.It street and listens to the same stations on a is getting more and more crowded, but that friend's nine-valver, but doesn't think they, He has been listening to the U.S.A.police seems to be an advantage, rather than a are as readable as they are on his " two." cars working just below 10 metres, and fault, from the average listeners point of W. J.R. (Leytonstone) is adding my finds that on certain days they come over view.The transmitting men find it other- adaptor to the S.T.700, and wants to know asstronglyasthe19 -metre broadcast where the " Grid - " terminal goeq, as stations.From some of the lurid extracts wise ! there is only one pick-up terminal on the he sends me I should think it's as good as 31 -Metre Band Very Reliable " 700." The answeris : toG.B.-1.. going to see a gangster film.He has also There is not much to be said about the Others, please note. loggedtremenous amount of DX on the short-wave broadcast bands.31 metres amateur 10 -metre band ;and has heard seems the most reliable of them all, but Reaction -Control Position W 9 X K announcing himself as " the high - really bad days on 19 metres are few and A. M. S. (Birmingham), says :" I think frequency experimental station W 9 X K," far between.Conditions down there are it is rather silly having the reaction control but not giving his frequency. certainly variable at present, but one can at the side of the sets in the standard base- Talking of frequencies, by the way, what generally find the " Yanks," even on the board series, as I have found on the ' Sim- do readers think of the idea of dropping most indifferent of all -wave receivers. plex Two ' that if the hand is placed behind wavelengths altogether in these ramblings ? Forty-nine metres is filling up with the the panel the signal fades away."Several I, for one, should be glad to say good-bye usual motley crowd of South American points there :(a) Don't place your hand to them.It's just as easy to think of " the stations, which are as difficult as ever to -" behind the panel " if you find that.(h) 28 -me. band " as " the 10 -metre band." identify.One of these days I am going to The reaction condenser isn't " behind the The amateur bands are 3.5. 7, 14, 28 and have a systematic round -up with a cali- panel," anyway ;it's at the side.(c) If 56 megacycles, And the broadcast bands brated receiver, and I hope to find out the " Simplex Two " had been arranged for are 6, 9, 12, 15 and 18 megacycles roughly. what the noise is all about ! " sideways reaction," you wouldn't find It's so much more logical thinking in A tip for those who like amateur -band that. kilocycles and megacycles, and talking about reception-get busy on 80 metres from now The same A. M. S. uses a screened -grid ultra -highfrequenciesinsteadofultra - onwards.Several of our best-known DX detector and pentode L.F., but wants to short waves.But I don't mind betting workers are on 80 metres at week -ends, and add two more valves, one fore and one aft. that there would be an outcry if I did it the Americans and Canadians come over In other words, a buffer stage and a power without " asking permission."What do very well late at night. stage.Well, he'll have to drop the pentode you say, some of you keener ones ? W. L. S. Popular Wireless, December 5th, 1936. 311

ments represent the birth of all -wave radio on have been successfully overcome, and it can a large scale in this country, they are obviously intruth be said that the stage has now been IN this matter of all -wave radio, and in the the outcome of years of research, and there is reached where,conditions permitting (and way that it has been launched upon, may certainly nothing " experimental" about them. that, may 1 add, is more often than not) the I say, a wondering world, British manu- It is very necessary to remember, of course, ordinary man -in -the -street can probe to the facturers generally are deserving of a particu- that all models in which short-wave facilities ends of the earth for his broadcast entertain- larly hearty pat -on -the -back.That is ment with no more effort or techni- my considered opinion now that I hue XCAMIlit.145-Tit,ligACifaStfglIgAMX-refaff4=liStf4aZcal knowledge than has hitherto been had time not only to probe intothe called for in connection with recep- The great swing -over from two- to three-, four- and tion on the ordinary broadcast bands. secrets of the 1937 all -wave models, but five -waveband receivers has happened in such a relatively in many cases actually to test them. But none of us have money to short space of time, that the ordinary listener is apt to sparefor As we all know, short waves are not find himself in something of a quandary as to what he haphazard experiments, They have been " in the air," so and this tremendous swing over from new. should do about it. two- to three-, four- and even five - to speak, almost aslong as orthodox It may be stated with certainty that all -wave radio is here broadcasting, and a certain clique of Ins waveband receivershashappened for good, and with this illustrated survey by G.T.Kelsey withsuchsuddennessthatthe have derived our radio entertainment off of the most outstanding models at present available, the the beaten broadcast track for upwards ordinary listener is apt to find him- reader will be able to become acquainted not only with self in something of a quandary as to of a decade. the features ofindividual receivers but withall -wave what should be done about it. But at no time have we been able tendencies generally. toclaimtorepresent more thana Without a moment's hesitation 1 very minute proportion of the listeningItsgrg/tli-leoi-PilNiMkg2M-VVVIroNltg--M-V-VMMITOW.Itadvise you all to go in for all -wave public as a whole; and although the set - reception at the very earliest oppor- makers have been aware of our presence and are provided are subject to the vagaries of re- tunity, and what more 'appropriate time is have, in fact, shown a lively interest in our ceptiononthesebands.No amountof there than thisseason of the year when activities, their first concern very properly has technical skill in the design stage can over- inevitably thoughts of the Empire and of our been, and is, with the masses. come that. fraternity overseas become uppermost in our That is why, until this present season, the But certainly many of the old bug -bears minds ? various manufacturers have steered well In an endeavour togive you clearofdesignsinwhichshort-wave guidance upon the selection of an facilities are included, for prematurely to all -wave receiver to suit your par- have entered this new sphere of manu- ticular requirements, I have chosen facturing activity might well have put what I consider to be an outstand- paid to it for good and all. ing design in each of practically all That would have been fatal. of the leading makes, and the details So they have waited.They have re- which follow will, I hope, serve to sisted the temptation to make capital out put you au fait not only with present of anaspectof radio in which there tendencies generally, but with the Is, and has been, tremendous inter- individual features of the various est,until progress technically has models discussed. reached the stage where a reasonable measure of success can be guaran- A Representative Survey teed not merely to the technically May Isay in passing that my minded few-the " clique," if you aim in compiling these details has like-but to listeners as a whole. been to make the survey as repre- sentative as possible.It does not Excellent Sets Available follow, therefore, that where refer- And upon the saneness of their Al A ence is made to a particular receiver policy, and more particularly upon 0 0 0 that it is the only all -wave design the resultsof thatpolicy which in that range, nor yet thatitis are reflectedin the general excel- necessarily the most ambitious one. lence of the models now available, The mere fact that it is included in they are,in my opinion,tobe his survey may be taken as an indica- congratulated. tion that there is something about it Despite the fact that thisis the first that lifts it right out of the rut, and season in which all -wave models can be that is all that need concern us. said to have ousted ordinary two -waveband First on the list alphabetically comes designs in so far as numbers are concerned, Cossor, and, asone might have ex- the instruments available are almost with- pected, they have entered the all -wave out exception of a very high order tech- fieldwith a design thatisentirely nicallyand they possessnoneofthe unique; in fact, I believe I am correct shortcomings which might reasonably have in saying that it is the only set of its been expected from " first -year " designs. kind on the market. From a survey of the technical merits of Pr.. Ai A e Fundamentally itis a straight three the sets now available,itbecomes very on broadcast and long waves, com- prising a variable -mu pentagrid 11.F. apparent that a lot has been going on The eight -stage superhet forA.C. mains operation isth behind the scenes, for although these instru- firstall -ways addition to the famous Ekco family, (Continued overleaf.) 344 Popular Wireless, December 5th, 1936.

a grid in the H.F. bands is literally child's play, and the settings amplifier section. at which they are received can he perman- Followingthe 460 ently and accurately recorded.It is but one kc.I.F. amplifying of many original features which combine to stagecomes the make the Ferranti " ATcadia " of particular double -diode - triode, interest tothe listener who may not pre- the two diodes pro- viously have attempted short-wave reception. viding A.V.C. and demodulation, while the triode is utilised Automatic Selectivity Device as an L.F. amplifier The Ferranti " Arcadia " receiver, which is andis resistance - available as a table model, as a console, or as a coupled to the steep - radiogram, is an. eight -stage four -valve (plus slope pentodeout- rectifier) superhet with a new and highly put valve. important technical development. It is common knowledge that the return to As atypicalin- popularity of the superhet circuit was mainly stance of the great on account of the high selectivity that could care which has been be obtained from it.But high selectivity lavisheduponthe inevitably causes the higher musical notes to design of this instru- be under -reproduced, or even not to be repro- ment, the H.F. sub - duced at all. And because the degree of selec- chassis is resiliently tivity required at different parts of the tuning mounted on rubber range is not by any means constant, itis buffers to eliminate obvious that the ideal is to have a scheme This ingenious all -wave design in the bugbear of whereby the degree of selectivity can be varied. the Cossor range isavailable formicrophony on short battery or A.C. mains operation.This is our By means of a small control fitted to the artist's impression of the chassis of the mainswaves.That is but " Arcadia," when a station has been tuned -in model, which is known as the 3783. oneof many such the selectivity can be reduced to the lowest features that could level possible consistent with the satisfactory (Continued from previous page.) be mentioned ifspace permitted. reception of the station with, of course, the stage, an H.F. pentode detector and pentode The Panoramic " Edgeon " floodlit dial is attendant advantage of improved top -note output, but when the wavechauge switch is calibrated in station -names and wavelengths, response. But the most remarkable thing placed in the " short " position, the switching and the tuning range on short waves is from about the scheme employed by Ferranti is is ingeniously arranged to transform the that when the tuning control is again set into a superhet.From the short- A PATENTED ARRANGEMENT rotated the setautomatically readjusts wave point of view this clever trans- itself to the most selective condition? formation has distinct advantages, not The Ferranti " Arcadia " table model, the least of which isthe great sim- which is for operation on A.C. mains, plicity of tuning which results on the costs 15 guineas, and the short-wave one band where tuning ordinarily might tuning range is from 19-51 metres. present difficulty. As a representative 'example of the Cossor's have thus succeeded in com- finerange of sets produced by the bining all the advantages of a superhet G.E.C. I have selected for inclusion in on short waves with the attractive this survey their " Fidelity Short Wave simplicity of a straight set on medium Five," a title which is something of a and long waves.But for this clever misnomer really, because the set covers combination, the price of the Model 3733 medium and long waves as well as short. battery receiver might well have been In the ordinary course of events one considerably in excess of that at which could feel absolutely assured that any- it is available --i7 15s. excluding bat- thing bear4ag the name of G.E.C. was teries-but as it is, it is an exception- second -to -none; but in this matter of ally attractive proposition. all -waveradiothisinternationally The 3733isremarkably simple to famous firm are perhaps at more of tune, and the calibration of the dial By a clever system of lenses and mirrors the Ferranti Magna- an advantage than most other firms, both in wavelengths and station names scopic dial provides a " band -spread " scale which is invaluable for short-wave reception. for they have specialised in the pro- greatlyfacilitatesthe reception and, duction of short-wave apparatus for the more particularly, the identification of dis- 19 to 50 metres.The price of Ekco model export market for many years, and the ex- tant stations.The all -electric equivalent of AW.87 is 12 guineas. perience thus acquired no doubt accounts the 3733, which is known as the 3783, retails As most of you will know, the secret of in large measure for the superlatively good at £9 15s., and it is designed for operation on success with any set intended for short-wave (Please turn to page 346.1 A.C. mains.The short-wavecoverage of reception is very largely both of these setsis from 17.25 metres to a matter of the tuning 52.5 metres. arrangements employed, THEMAGNASCOPIC DIAL and because of the way An Ekco Masterpiece inwhichshort - wave Eke() appear to have concentrated all their stationsareaptto research and manufacturing facilities upon crowdthe relatively 20 22 24 the production of only one all -waver for the smallsectionsofthe time being, with the not unexpected result dial at which they are 111.1111111111111i1111111IL that the set in question is nothing short of a received,any schema masterpiece of design. designedto" spread The AW.87, asitis called,is an eight - them out" is of inestim stage five -valvesuperhet with ahostof able value. clever features, for operation on A.C. mains. Itis partly because NtANIWTO,OLAND *BERLIN N ROME BRUSSILSBEROWR ABERDEEN 0 SCOT. N 0 A E CIONAL muNICH IRRAWE ATHICoNE The circuit comprises triode-hexode frequency - of this that I feel dis- ANII R.NORIAANDiE NAIABLAC "SCOT R. 0 NORTH R. ST-uTTGAR-I changer, H.F. pentode I.F. amplifier, double - ONE ONENCASTLEOPPARISIEN OwLST 50T if NS VIENNA PE1E6004, posed to give top marks 11 0 NATIONAL" N. IRELAND $ MILAN 'STOCKHOLM FLORENCE 04.I.LES diode -triode for second detection, A.V.C. and to the clever " Magna- 250 34D 330 4.13, 1,0 'EV 330 L.F. amplification, and steep -slope pentode scopic " dial idea that emmr, 200 TIFL, KALUNDE1.6 DROFTWICM CON:a , output, but it is in the practical conception is an exclusive feature F f MOSCOW LUXEME,G (ALIT., OS HUf ZEN OSLO I WARSAW 0,0,5 of this fairly orthodox circuit that the set oftheFerranti all - cooOJACHE 'PONE stands out a mile. wave superhet receivers. 11). The input from the aerial to the " mixer " Withthis ingenious valve is via an inductively coupled bandpass scheme, the principles filter except on short waves, where a single ofwhichareclearly tuned circuit is employed.The aerial primary shown inone ofthe on short waves is suitably arranged for con- illustrations accompany- nection where desired to a doublet aerial. ingthisarticle,the Mixing "inthe This chise-up picture of the tuning arrangements of the FerrantiArcadia " frequency -changeris logging of distant sta- receiver shows clearly the optical effectof the Magnascopic dial.The effected by modulating the electron stream by tions on the short-waiv, molested scale is, of course. the one above the main tuning scale, Popular Wireless, December 5M, 1936. 345

" HERE'S SOMETHING THAT

WILL GUARANTEE YOU GOOD

RECEPTION THIS CHRISTMAS ".'

'PLEASED TO WORK WITH YOU, I'M A GIFT TO HIMSELF, HE SAID MY "INDICATOR" WOULD PREVENT HIM BEING LET DOWN THIS CHRISTMAS.'

GIVE AND GET

tX0CANID ittiOCX BATTERIES THIS CHRISTMAS

'STILL KEEP GOING WHEN THE HEST HAVE STOPPED' EXIDE `I-IYCAP'-the L.T. battery for modern sets DR YDE X -the Exide H .T. battery

Obtainable from any reputable dealer or Exide Service Station. Exide Batteries, Exide Works, Clifton Junction, near Manchester. Also at London, Manchester, Birmingham, Bristol, Glasgow, Dublin and Belfast 346 Popular Wireless, December 5t11, 1936.

Continual from page 344 andfrom750 - 2,200metres. performancegiven by this present model. Whileitistrue that practic- The set is a de luxe four -valve (plus rectifier) ally all of the important short- superhet with the circuit sequence of triode- wave broadcasting stations radi- hexode frequency - changer,I.F.amplifier, ateonwavelengthsbetween double -diode -triode combining the functions roughly 16 and 51 metres, the of demodulation, A.V.C. and L.F. amplifica- additional facilities provided in tion, and finally pentode output. It is designed the H.M.V. Model 481 are very for operation on A.C. mains. well worthwhile, and it is a fact The practicalconceptionofthismost that many of the stations' to be popular of all superhet circuits incorporates heard off the short wave " beaten many novel and exclusive features, among track-" are even more interest- which I should perhaps mention the special ing than those on it. fidelity scheme for the reception of powerful Inkeeping' withthe -high stations, the variable " muting " device and traditionsassociatedwith:all the " Variable Brilliance " tuning indicator. H.M.V. apparatus, the '481 is a Incidentally, the wave range on short waves is masterpieceofdesign, andit from 16-50 metres. isfittedwithallthe worth- while refinements that stamp a Receives Television Programmes set as thoroughly modern.It is With the advent of television broadcasting a five -valve (excluding rectifier) in this country the term all -wave reception superhetwith an H.F.stage has assumed a new significance, for, strictly preceding the frequency -changer. speaking, a set these days is not an all -waver This additional radio frequency unless it will receive the ultra -short waves in stageis no doubt one of the addition to the bands at present covered. reasons for the amazing sensi- In this chassis view of the McMichael 362 all -waver the IMO This fourth, or in some cases fifth, wave- tivity of the 481.It is equipped " band -spread " pointer, which is so valuable on short waves band will obviously become of greater import- with two -speed tuning (an in. and which works rather like the second hand of a watch, can ance as the regional scheme for television pro- valuable refinement where short be seen below the main pointer. gresses, for, although the price of complete wavesare concerned),vernier television receivers will be beyond McMichael Model 362 is a four. most of us for some time to come, valve A.C. superhet with a differ- there is nevertheless widespread DESIGNED FOR QUALITY ence, and that subtle difference liftsitright outoftherut. interest in this latest innovation, Ordinarily, where four valves are and the incorporation in commer- employed in a superhet circuit, cial receivers of facilities to listen the first valve is almost without to the sound side will no doubt exception the" mixer "valve, constitute a vital sales argument and it is followed in turn by the as time goes on. I.F. valve, the three -in -one de - H.M.V., well to the front as e usual, have alreadyanticipated modulator-A.V.C.-L.F. amplifier

this additional listening require- valve,andfinallythe output ment,andwithcharacteristic ,valve.Not so the McMichael:362. enterprise have made provision Two -speed Tuning foritinthedesignof their. The circuitsequence in this Model 481. caseisscreenedpentode H.F. This particular receiver is prob- amplifier,triode - pentodefre- ably one of the most,ifnot, quency -changer, screened pentode indeed,the most ambitious all - I.F. amplifier with a double -diode wave design of any available in pentode as the final stage. The this country, and it is one of the arrangement is certainly unusual, few sets that cover from 7 metres but the results warrant the belief to 2,200 metres with no impor- that insomerespectsithas tant breaks in the tuning range. definite advantages over the more This extraordinarily wide tuning popular arrangement. For one range is covered in five steps of High-fidelity is an outstanding feature of the G.E.C. " Fidelity Short -Wave Five." thing, the sensitivity is of a much from 7-16 metres, 16.7-53 metres, The clean lines of the chassis will be obvious from this bird's-eye view. higher order, and thepre-H.F. 46-140 metres,185-560 metres, stage ensures greater selectivity. indicator, indepen- As a matter of fact, the whole design from AN INGENIOUS CIRCUIT dent bass and beginning to end provides ample evidence of trebletonecon- the great care with which the instrument has trols, and the dial, been thought out, am will be obvious from the which is illumina- following details. ted,iscalibrated When the set is being tuned normally, a instation names reduction ratio of 20-1 is given by the main andwavelengths. tuningcontrol.Butinvaluableasthis The retail price of reduction ratio is where short waves are con- the 481 (which is cerned, it is apt to be a trifle irksome when it for A.C.mains is desired to make a quick change from one operation)is18L part of the dial to another. The designers have

guineas. - thereforeintroducedaningeniousdevice Although t h e whereby slight pressure on the tuning knob vogue 'for allswave automatically brings into use a " fast " ratio radio can only be of 3-1. said to have started Another valuable feature on short waves is this year, the first the " band -spread "pointer, a small inset McMichael a 1 l - scale and pointer, rather like- the second hand wave set was actu- on a watch, which rotates several times faster

ally marketed over than the main pointer. ten years ago. The These are but two of many such features experience accu- to be found in the design of the McMichael 362, mulated since that and at 151 guineas it seems assured of wide- VT! time isstrikingly spread popularity. in evidence in With nearly half the country still without theirModel 362, mains of any description, it is gratifyino' to find which is a glowing that theall -wave requirements of battery

This is the circuit of the battery version of the Cossor all -wave receiver and it is exampleof1937 users have not been overlooked. catalogued as the Model 3733. The set functions as a" straight " three on medium all -wave radio at and long waves, but is cleverly transformed into a superhet when the wavechange switch is placed in the short-wave positions. its very best. (Continued on next page.) Popular Wireless, December 5th, 1935. 347 tions are taken in plane colour -coded dial and a new tour -way the design to en- wavechange switch, the control of which is sure that the par- colour -coded in like manner to the (lift!.Con- ticular band in use fusion in this caseis,therefore, quite im- is clearly indicated. possible, and by reference to the colour indi- Itisobviously cationthelistenerknows instantlyover ofvitalimport- which waveband the set is being tuned. It is ance forthe a simple scheme, I know, and, inch ed, it appeals "iitio0111 various settings to me mainly because of its extreme simplicity. iii t. of the wavechange But it is an example that certain others would switch to be de- do well to emulate. notedeitherby clearly readable A Skilfully-Designed/Receiver markingsonthe This is but one of the many ways in which knob itself or by a this battery all -waver of Peto-Scott's bears separate indicat- evidence of skilful design. In all other essential ing device coupled respects itis,in my opinion, an instrument to,and actuated that can be held up as a striking example of by, the switch thetremendousprogressthathasbeen mechanism. made in all -wave designs-and particularly in Inthisrespect the battery -operatedclass-for the present particularly I feel season. thatthe Peto- The circuit comprises a variable -mu B.F. Scott Company arc pentode,a high -efficiencydetector and a deserving of com- Harries output pentode, and the main tuning m endatio n,for control provides alternative reduction ratios their all -wave S.G. of 8 :1 and 100: 1, a gearing combination that battery three, isideal for a set covering short waves in Model 7032, is pro- addition to medium and long.Incidentally, vided with an air- the two short-wave ranges on this set cover This is one of the first sets ever to be produced from 14-31 metres and from 28-62 metres. with which the sound side of the television pro- The Pete -Scott Model 7032 incorporates a, grammes can be received in addition to short. " tone - compensated "permanent magnet medium and longwaves.Itis theH.M.V. Model 481. moving -coilspeaker, and allthe necessary batteries (which arc housed inside the cabinet), (Continued from previous page.) the valves and even the aerial equipment are included in the price of £7 15s. Od.Itis The Marconiphone Model 375, for instance, obviously a set that, by virtue of its remark- is a battery -operated three -band set of which able low cost and exceptionally attractive the makers have every reason to be proud, specification, isdestined to and in my opinion it justifies inclusion in this become universally popular. survey ofthe outstanding models on the three -fold score of performance, price and Insofar as the short waves economy of upkeep. are concerned, the general con The circuit incorporates several interesting elusions which may be drawn refinements. The aerial arrangements comprise from my survey of the 1937 an aperiodic long and medium wave coil all -wavers are (a) that the range connected in parallel with a short-wave H.F. covered must not be less than choke which, on short waves, diverts signals from approximately 19-51 metres (b)that direct to the grid of the H.F. amplifier, which, some sort of slow-motion gearingonthe in turn, is tuned -anode -coupled to the leaky - main tuning control is absolutely essential, and(c)that wavelength calibration, while grid detector. Peto-Scott's are respon- sible for this attractive not indispensable, is highly desire ble. Tapped L.F.-Coupling Transformer all -wave S.G.3 for the battery The L.F. coupling consists of a resistance - user. Itisknownasthe fed transformer, the secondary of which is Model 7032. tapped to the wavechange switch. This provides two alternative ratios, the higher ratio on short waves resulting in higher gain on this waveband. The set has only three controls :a two - ratio tuning control, a wavechange switch, and an ingenious dual volume -reaction control. This last-mentioned control acts purely as a volume control on medium- and long -wave stations, and a pre-set reaction control in the detector stage ensures that the gain remains at rnaximun.On the short waveband, however, reaction is applied by the volume -control, and the vernier movement enables a fine setting to be obtained. Someideaoftheeconomicalcurrent demands of this set will be obtained from the fact that under normal operating conditions it takes only from 6-71 milliamps. The priceof the " 375 "is91 guineas, including all the necessary equipment.The short-wave coverage is from 18-50 metres. The almost universalpopularityofall - wave designs this season and the consequent necessity for dials with scales for the calibra- tion of as many as five wavebands not un- naturallyresultsinconfusionfromthe listener's point of view unless proper precau-

ISMIZ-WX--'W.:4"W.-11WACIAC.VAK cX.---reeikTZ'''. The Marconiphone Model 346isa five -waveband receiver covering from 7-2,200 mAres.Note the clever concentric riarrangement of the ditl3rent wavebands on the calibrated scale. 46%-7.M.71,21;:ro.:13570-7-11,-2,16V-71.'-7'...1M-n1V.55 110ra-P.07.:;.M 348 Popular Wireless, December 5th, 1936.

FROM OUR READERS tf#:ufisazik-A.--rzfam:gm-fia--gmufx14-criowyt 0 FOR THE BEST LETTER it ';'1 Readers should note that a Guinea isk ABOUTTHE SERVICEMAN awarded each week to the sender of thek 0.best letter in the opinion of the Editor. 01 radio dealers generally, I think that the employer is4iLiterary skill is no criterion of success, y, Further Letters from Readers in most cases, to blame. After all, a really good serviceman is worth a good nor islength, and no radio subject is; ontheInterestingSubject salary, but how often does he get more than £2 10s. barred.This week the guinea goss to per week ?That is good (?) pay for a serviceman in Mr. E. Fisher. Recently Raised by a Letter most districts, yet the employer doesn't know probably yg the first thing in fault finding.I feel sure that if Printedin These Columns. better wages prevailed good service engineers wouldIY%Cgg.fClq'KU-MtZfZfZUWZ,ZITZALfCfik*f6 be available.Also, servicemen and salesmen should work independently, as no salesman will bother about To this end a careful study of manufacturers' service if he has the slightest chance of inducing the literature is made, the new features of every set being unfortunate customer to buy a new set. noted and memorised.Trade papers, too, are read The Editor, POPULAR WIRELESS. Personally, I believe that when dealers wake up to avidly, while journals such as POPULAR WIRELESS Dear Sir,-I was interested to read the the fact that their sales are affected by theirbad which, as he well knows, reflect the feelings of the servicing they will begin to clamour for good service keener section of the listening public, are read from letter of Mr. Donald T. Kear in your issue engineers.As long as low wages are the rule they will cover to cover. of Nov. 14th re dealers and radio repair clamour in vain. Another -enthusiast takes so much interest in his Now, you dealers, what about it ?Correct me if I job that he gave up a week of his holiday last summer work. A knowledge of actual facts may am wrong. to explore the factory of a set manufacturer fifty -odd perhaps add something to his remarks. Wishing " P.W." staff and J. S. -T. every success, miles from his home.This salesman, who already Unfortunately, at the present time the Yours truly, knows as much about television as Baird himself S. A. PALMER. does, would be ashamed to admit that he ever let a radio trade is in a state of chaos.Sales 92, Lodge Road, Redditch, Worcs. receiver pass through his hands without knowing and service are very often in the hands of every detail of its construction. the same person-a contrast to a similarly IN DEFENCE OF RADIO SALESMEN In conclusion I should like to repeat that the writer The Editor, POPULAR WIRELESS. whose opinion of radio salesmen is so poor has been developed trade, that in automobiles, in Dear Sir,-The correspondent who, in your issue unfortunate in his encounters.There are indeed which salesman and motor mechanic are of November 14th, deprecated the attitude of the many to be found who are a great credit to the in- In radio average radio salesman and suggested that there arc dustry that they represent. two quite different occupations. more young fellows with an easy flow of talk than Yours faithfully, this combination has become almost un- there are young fellows who are prepared to study ARTHUR E. ROBBINS. avoidable for the following reasons. radio, appears to me to have been singularly unfor- tunate in having met only this type of salesman. 28, Union Road, Clapham, S.W.4. The average dealeris,asMr. Kear My occupation brings me into contact with many myself am not a radio salesman. remarks, quite ignorant of the first principles young men whose job it is to sell radio sets.Most of of the science-so ignorant that he FOR S.T.800 SETS. The Editor, " Popular Wireless." expects a youth of 18-20 years to Dear Sir,-I am sending to you the en- have a complete knowledge and full A READER'S SPEAKER IDEA closed composite sketch of my own design for a speaker cabinet to match and fit on to the experience of servicing, and that at top of Peto-Scott's " Easy Cabinet " for the wages that would not allow him to S.T.800 set. purchase even a copy of your excel- The sketch shows the speaker cabinet fitted to the " Easy Cabinet," and if you think it lent journal if he had to depend on worth while I should like you to pass the his work for a living.On the other design on to your readers to copy.It is made at a cost of about 2s. 6d. and I would be glad hand, he knows that for every set to send a carbon copy of the design to anyone soldhemustrisk,athis own wishing one at a small cost of 6d., post free. expense,repeatedcallsonhis Yours sincerely, K. LANGLEY. serviceman's time, even for such Victoria Street, Englefield Green, Surrey. trivial things as replacing the old [Editor's Note :We must make it clear H.T. battery with a new one. that while we consider Mr. Langley's design most attractive in appearance, we have not The better -class dealer asks his technically tested this particular speaker -set " service man " to act principally combination.] as salesman so that he can offer a WHERE THE CURRENT WENT man a proper wage and a progressive The Editor, POPULAR WIRELESS. position. Thereforeheemploys Dear Sir,-Being a regular reader of your one with an " easy flow of talk," as interesting periodicalfor many years,I think the following experience I had in my Mr. Kear says (since this actually service work a short time ago might prove of brings him profit), and has to rely interest to your readers. on some outside firm or individual The receiverI was called in to service was a three -valvebatteryset,and the toundertake themoredifficult owner complained ofit having consumed repairs. two H.T.batteries in thespace of two weeks.The set was placed -on a small The fault for this state of affairs table close by a window, and before making lies largely with the manufacturers any tests I removed the table slightly from the wall.Putting a reliable milliammeter who in their advertisements offer a in series with the II.T. negative lead showed period of guarantee with their sets the current consumption to be 8 MAL, thus leading me to believe that there was no and then leave the dealer to provide internal short-circuit. it. Ifevery manufacturer stipu- The grid -bias battery also showed a full lated that a certain small number of voltage on test and itsleads were O.K. I might also add that the set was giving free service calls would be allowed, The suggested loudspeaker idea for the S.T.800 to which Mr. Langley excellent results on the new H.T. battery and after them a certain definite refers in his letter. This is a reproduction of the actual sketch which I had fitted.After everything seemed he sent. in order I was about to inform the owner charge (in addition to the cost of that his receiver was O.K., having placed replacements) would be made, the the table on which the set reposed against dealer would know at least exactly where them realise that an extensive knowledge of a set's the wall again, when I happened -to place my hand " innards " is of vital importance to the success of on the wallpaper over the set, receiving quite a nice hestands.In addition,Isiscustomers their career.I use the term " career " deliberately, shock and also noticing the dampness of the paper. would be more inclined to learn something for many of these young men sincerely believe that This gave me a clue, and upon examining the back the industry holds a bright future for them and, in of the receiver with the table in its original position about the simpler details of the sets they my experience, they act accordingly. I saw a loose piece of wallpaper touching the H.T. have bought. For example, evening classes as well as indepetii- +120 battery plug. Yours faithfully, dent lectures are attended regularly.Not a few of The -plugs were of the spring pattern in which a my salesmen acquaintances spend considerable sums large piece of the bare plug protrudes above the level E. FISHER. on text books.In fact, they swot up the whole of the battery top.The solution of the problem was 33, Freeth St., Oldbury, Nr. Birmingham. business of radio in much the same way as a doctor then simple-the wallpaper was making all earth or lawyer pursues his studies in the attempt to be- connection due to its damp condition, and the H.T. come proficient.Above all things, enthusiasm is leakage was being caused by the loose portion of the NOT PAID SUFFICIENT always in evidence. paper' touching the positive plug. The Editor, Popular Wireless." The example of a junior salesman in the employ of Yours faithfully Dear Sir,-I feel I must write in support of Mr. one well-known retail trader is typical of the spirit J. D. KENNY. D. T. Rear P.W." November 14th). which I have always had the good fortune to find Killeragh, Banagher, Offaly, I.F.S. With regard to " Service Salesmen," I agree that behind the radio counter.This young man is con- few have any real technical knowledge, and in my stantly trying to,keep ahead of new developments IA puzzling fault and one whichitwould have experience they do not attempt to gain any. As and ideas in order that he may always know a little been easy to miss.It goes to show how alio things retards thost employed as " Service Salesmen " by more than the most technically Minded customer. can cause a heap of trouble -Ed 1 Popular Wireless, December 5th,1936. 349 144-

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Well, we think they are-but how can we prove itto you ? We can say our con- densers last longest, are the most reliable, and make lots of other claims for them, but you'll just reply that we're biassed- and maybe we are ! Of course, we might mention at the same time that we've been making condensers for many years, that we've shown the way on many new types, and that the majority of the big wireless manufacturers fit our components. And that's something that doesn't have to be proved.

Colvern are the makers of highly efficient short wave.coilsfor all circuitrequirements. Fullydes- criptive leaflets are obtainable on application. NEMER Why not adapt your present set for short-wave reception by means of the Colvern Converter ?Write to us enclosing 3d. in stamps for DUBILIER CONDENSER CO. (1925)LTD., constructional blueprint. CUCON WORKS, VICTORIA ROAD, NORTH ACTON, LONDON, W 3 COLVERN MAWNEYS ROAD, ROMFORD, ESSEX, C. 0. Casson 9 LONDON DEPOT, 150, KING'S CROSS ROAD, LONDON, W.C.1, 350 Popular Wireless, December 5th, 1936. CHRISTMAS COMES BUT ONCE A YEAR- Claude Dampier tellsreaders how Mrs. Gibson and her guests enjoy themselves at Christmas giv...zasmcfg-

lICRISTMAS-Y-e-e-s. Once ayear. Well, I went up into the loft-isn't it But isn't it lovely ?Just think of it. dirty up there-or perhaps you've never Christmas pudding-and turkey-and become Father Christmas-anyhow, I pity nuts.Oh, and of course-Mrs. Gibson- the poor fellow in the modern homes. ye-e-e-s. She's very good at Christmas. No chimneys and only the loft to hide in, She is definitely Christmas -minded. all among the water cisterns and spiders. Especially the good cheer part ofit. I got my beard dripping wet when I was I've been watching her make the puddings crawling past the cistern trying to find my for this Christmas-wonderful conglomera- way to the hole in the ceiling.I found CLAUDE DAMPIER, as he appears in private life. tions,fullof flour-and water-and allit at last, but it was not the right hole. that wouldn't do.What is, the good of those marvellous things you put in as well I put my foot between the rafters and goino' to the lost property office until the -orangepeel-bits of meat-suet-went right through on to Mrs. Gibson's umbrellas are really lost.These have all currants-and grapes that have lost their bed. been found, sothe lost property office will power-you know-raisins, and all I don't think she was very pleased about wouldn't take them, would they ? sorts of other things. it, you see she had a slight headache and But what I should really like to do on was lying down for a few minutes while the Mrs. Gibson's Latest Idea. Christmas Eve, is to throw a party in one children's surprise was on.But she got the of the studiosofthe B.B.C.Do you Then there are the charms --very im- surprise herself. portant-Mrs. Gibson's Christmas puddings think they'll let me?I'd like to get a are always full of surprises.Ye-e-e-s-she I think she ought to have been delighted. good crowd together-you know-Henry puts in all kinds of odds and ends-old Not many women have Father Christmas Hall, John Sharman, and Bryan Michie ; corks-razorblades-string-andany- dropping in on them like that, do they ? I thought they might do the Three Bears thing that might come in useful. No.But she was really annoyed, and as a sort of charade. Her latest idea isto add a couple of accused me of beim,. absent-minded.Well, Then I'dlike Val Gielgud and Eric camphor balls to each pudding, which is perhaps I am, but I'm not the only one, Maschwitz to take the parts of Romeo and she's very absent-minded herself. Ye -e -e -s. Juliet.I think Eric would make a lovely very clever,I think, because one never She's always losing umbrellas. knows how long one might have to keep a Juliet. Ye -e -e -s. I have plenty of plans Christmas puddingandthey'rehorrid for a real good Christmas party, but I don't when the moths get in them. And She Finds Them Too ! suppose they'll let me have it, and I shall You know, people are always asking I suppose she has lost about thirty this probably end up by accepting Mrs. Gibson's me what I do at Christmas.Well, what year.Terrible,isn'tit ?Mind you she invitation to go round and help her with do you do ?Play games and eat, then findsthemaswell-heapsof them- the stuffing or any other little odd jobs- eat and play games.That's all there is to ye-e-e-s, in trams and 'buses and various ye-e-e-s. it. places.The hall at her house is simply But joking apart, I hope you will all But I know some lovely games-by stacked with them.All awaiting owners. have avery Merry Christmas,plenty Jove,yes.We played thematMrs. I asked her why she didn't advertise for the of good fun-don't forget toltry the games, Gibson's last year.First of all we had owners, or take the umbrellas to the lost and think of me at Mrs. Gibson's, won't " Blind Man's Biff "-a marvellous game. property office. " Ohno,"shesaid, you ? You give all your guests an umbrella each, and then they each have to pick out some during the evening perforMance only. Another object in the room, such as a clock or vase SEEN ON THE AIR item on the same day, A -description of wireless or whatever they fancy most, and then (Continued from page 340.) transmitting valves, would have rejoiced the when they've each chosen one, you blind- radio amateur, perhaps, but not the vast fold them all and turn them round three majority of the television audience. times, then you say GO, and whoever buffs wet.In general the same remarks apply, even I regret that I did- not see Nina Devitt, the the ornament they've chosen first with the including the fact that it was also broadcast cabaret artist, who in my view is one of the umbrella wins the forfeits.You must try four times during the week. most attractive of television artists. Mr. C. H. it,it was a smashing success last year. My enjoyment of " Inn Signs Through the Middleton scored a distinct success with his Ages," described by Mr. Fred Taylor,. R.I., first television appearance, showing us how Then there was " Hunt the" Kipper," 'was somewhat marred by two black mackerel to prune fruit trees.It is a great pity that the which is great fun, the only thing is that back bands across the screen due to local B.B.C. cannot distinguish between a feature to play it properly you must be quite interference. Ithinkthisiscausedby which appeals to nine out of ten and a feature sure that all your guests smell, because diathermy, apparatus, but is easily the most which appeals to one in a thousand. if they can't it wouldn't be fair, would it ? serious form of interference which I have Pruning is obviously in the nine out of ten experienced. class and art demonstrations in the ninety. Father Christmas in the Loft. Next day Mr. John Piper returned to the nine out of a hundred. Then I played Father Christmas for the studio and brought a number of examples As I come to the end of this article I hear children, too.That was a great success. of pottery and sculpture on exhibition at that the campaign of programme criticism in The house had no ordinary fires, so there London galleries.This was another feature POPULAR WIRELESS and elsewhere is to bear with very limited appeal.I had excellent fruit." Something will be done about it," is was a littledifficulty about me coming reception, but confess that I could make little stated by Those Who Know. down the chimney. Eventually we decided of some of the curious objects shown. I calculate that at present television sets are that I should get up into the roof-you "The Mask Theatre," performed on the selling to dealers,hotels,restaurants, and know,theloft thing-and come down following day, gave one of my children who private persons -at the rateof about one through the hole affair in the landing ceiling. entered the room a fright.Here is another hundred a week.May the army oftele- The children were to be all lined up on the problem for the weary television executive. viewers increase more and more rapidly under stairs. Clearly I think, these items should be given the stimulus of enlightened progrn mine policy. Popular Wireless, December 5th, 1936. 351 THE "TELE-SOUNDER" A UNIT FOR RECEIVING THE TELEVISION SOUND PROGRAMMES ON ALMOST ANY BATTERY SET

By John Scott -Taggart, M.I.E.E., F.Inst.P., M.Am.I.E.E., M.Am.S.Mech.E., Fel.I.R.E.

CI BEAT newbroadcasting complete televisionreceiver.The sound recital of bagpipe ramie on the unit I am system is now available to all programmes which accompany the radiation describing in this issue, I must confess that constructors. At small cost ofpictures areexcellentinthemselves. I had no particular wish to see the bagpipes anentirelydifferentpro- Go to any demonstration of television, close being played. Nor is there any special joy grammeisavailable,thus your eyes, and you will still derive a very in looking at a dance band.I speak, of giving a choice of three B.B.C. great deal of entertainment. In fact, many course, for myself alone.There is very programmes. people think that the television programme, little of excitement in the evolutions of the The new television service has opened up even treated solely as sound entertainment, average dance band which perhaps explains a wonderful new field for the constructor. is more interesting than ordinary broad- why one or two leaders of such bands have Once again this class of the community can casting on the medium and long waves. developedthetechniqueof performing dart ahead and obtain what the ordinary This, no doubt, is due to the fact that the monkeys.Even a speech by a famous listener cannot achieve.Actual television artistsandspeakersareconsciousof statesman may sound better if ybu do not will develop slowly, as the chairman of the performingnaturally. Moreover,the see him blow his nose or sip a glass of water Electrical Musical Industries stated recently. announcers, including the two attractive - or whatever statesmen sip when they need Not only will the technical development be voiced girls who sometimes perform these support. gradual, but naturally only a comparatively rites, do not read their ordinary announce- few peoplewillbe ableto afford the ments.Further, other speakers and per- A New Source of Entertainment television receiver at present. formers obviously cannot read from a Scores of items, therefore, gain little by But there is one aspect of this service manuscript.The result is that what they vision, but of course, now and again, vision which is of very great interest indeed, and have to say comes over more naturally and means everything. Nevertheless, most of the which can be said to be perfectly developed. more attractively.Personality counts for programme is excellent without the vision That portion of the service is the sound a very great deal in television, and even and think what it means ! An entirely new part. As you know, the sound accompani- though you cannot see the performers on a alternative programme coming through at ment-whether music, song or speech-is sound receiver, yet the personality seems to excellent strength and wonderful quality ! radiated on a wavelength of 7.23 metres, come over with great effect. The quality of reproduction is theoretically while the visual portionisradiated on much better because there is no limitation 6.67 metres. A Tribute to Broadcasting of side -bands as in the case of the medium It is the sound portion which will prove One might expect that not seeing what waves and long wave B.B.C. stations. There such a great attraction to those listeners who was happening would detract greatly from isalso no need for selectivity ;in con- do not propose at this stage to acquire a the enjoyment, but this is far from being sequence no devices have to be used which the case.In fact, most of the time one is may impair to some degree the quality of hardly conscious that one is missing any- reproduction. Asregardsloudnessof thing.It is perhaps a tribute to ordinary signals,the present unit which I have broadcasting which we have accepted for called the " Tele-sounder," gives you full years as excellent entertainment although strength entertainment which is indistin- we never see what is going on. Even when guishable as regards strength from the everyone has a television set, only a fraction ordinary B.B.C. broadcast signals, while the of the time will be spent in " looking -in." quality is excellent. Listeners will still vastly out -number the You have, therefore, an entirely new viewers.Even assuming that the results (rmd inued overleaf) aretechnicallyperfect,only alimited number of subjects will be improved by vision.Hearing the other day an excellent

Thedesigneroperatingthe " Tele-sounder,"whichit shown connected up to the S.T.800, 352 Popular Wireless, December 5th, 1936.

(Continued from previous page.) programmes areone hundred percent to listen to the television sound programmes reliable in the area served by the station at once in order to realise what they have been situation.Everything that comes through Alexandra Palace. This service area is about missing. is of full programme value ;there is no 30 miles but there is no doubt that much fading, the programmes come through at greater distances will be covered. Excellent Programmes for Television excellent strength and with very good quality. Needless tosay,the Tele-sounderis Naturally to popularise television they Ordinary short-wave reception by its very only of interest to those within this range will be putting over excellent programmes of London, but other readers will be specially and this tendency will obviously become interested as television will be extended to more marked.People are not going to other centres such as Birmingham and buytelevisionreceiversatahundred ?), THE PARTS YOU NEED Manchester. pounds each, unless the programmes are TUNING CONDENSER : .000025-mfd., But in and around London alone there is very good.The policy of the B.B.C. will B.T.S., type S.T.C.425. AERIAL COUPLER :.00005-mfd.,J.B., a public of about base -board trimmer. ten million people FIXED CONDENSERS: 1 .00005-mfd., Lissen Mica, who will be 1 .0001-mfd., Dubilier type 620. intensely inter- 0 COM,Gai. 75 'a,,ge 1 .0003-mfd., Dubilier type 620. 1 0.5-mfd., T.C.C. tubular type 250. ested in receiving 0VALVE HOLDER :4 -pin, Eddystone No. 949 the television AL.F. TRANSFORMER : Varley Niclet, programmes by standard 1: 3.5. RESISTORS : sound.The 1 1-megohm, Dubilier I -watt. to present unit, the 1 30,000 -ohm, Dubilier I -watt. POTENTIOMETER :50,000 ohms, Erie, less Tele-sounder, can switch, but with terminals. be used on practic- cre4 SPECIAL COIL (specify this unit) : Coivern. ally any battery SHORT-WAVE CHOKE : B.T.S. type ,4/"ItErchatr .7541t%crop, 4, N4140 U.H.F.2. setalthoughit 2 KNOBS: Bulgin, type K.20. was primarily in- VALVE HOLDER ADAPTOR : With isolated tended to extend 2 C2vanwscer..Er. gridandtappedfilamentterminals, Constructional details of the tuning coil. Bulgin type A.36. the scope of the The dimensionsgivenarecriticaland J'AcrAe Of 0.-znectazg TERMINALS : A.1, A.2, A.3, E., Belling -Lee S.T.800sothat type R. should be followed carefully. WANDER PLUGS H.T.-'-, G.B.-. Belling - itwouldcover Lee Midget type No. 1019. practically every broadcast under the sun. therefore be, before very long, to put on SCREEN: Aluminium sheet,24 S.W.G., television programmes which will make 7 X 5 in., Peto Scott. Think of the great scope for a revival of TERMINAL STRIP :4 x 11 in., Peto Scott. home -constructioninthisfield ! Many thepublicrealise how much theyare rfi1 PANEL :Peto-Scott. battery users who have given up home missing.That is, in fact, the only way to 2 SIDE PIECES :Peto-Scott. 4 feet 18 S.W.G. tinned copper wire and construction or are using sets a year or two popularise television and the owner of a 3 feet 1 m.m. insulating sleeving. old will want to have this valuable adjunct Tele-sounder can benefit from this policy. which will give them an entirely new and If, for example, it is desired to popularise fascinatingalternativetotheordinary television by broadcasting such stars . as nature is not a hundred per cent reliable. B.B.C. programmes. Harry Lauder, nine -tenths of the entertain- You cannot, for example, guarantee the Not only, therefore, will you be building a ment will come over on the Tele-sounder. reception of Tokio at a certain given time Tele-sounder for your own set, but probably policy of the B.B.C. will be everyday. Butthetelevisionsound also for many of your friends who have only directed towards making you feel you are

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The whole of the wiring for the " Tele-sounder " is shown in this diagram.It will be noted that each lead is numbered.These numbers correspond with those given in the Rapid Construction Guide given on page 358 so that wiring up the unit is a very simple matter indeed. Popular Wireless, December 5th, 1936. nra

chimney. None out experiments with different breeds of ofthese,mind aerials. Suchexperimental work is you, are essential, peculiarly easy and costs only a few pence

as I have designed for wire. ' this unit to work As regards ordinary broadcast aerials, offanordinary there is no incentive to experiment with aerial. Atthe these.The highertheyareandthe same time I have clearerofneighbouringbuildingsthe provided two better.There is very little we can do with terminals for the them, and in any case, one cannot very benefit of those well experiment with high aerials requiring who wish, to carry lofty poles.But when you are dealing with aerials only a few feet long which can be VenrolirMfafr-MN suspended from a window or erected inside a room, the whole situation is changed and In appearance the a great field for interesting experiment is " Tele-sounder " is not unlike a mini- opened out and none of these experiments, ature version of the be it noted, need alter the receiver in the S.T.800. Everything slightest, so that you can always go back is mountedUni- planefashionon to the normal arrangement. the panel, which is supportedby two Short -Wave Mumbo-Jumboism little side pieces. In my S.T.800 article I had a great deal MSCAMMAglt. to say about the mumbo-jumboism of short- ing something, but if you wavedesigns,andhowa have a sound receiver which will RESISTANCE -CONTROLLED REACTION mysterious cult had grown up pick up the ultra -short trans- around an ordinary engineer- missions you will certainly be ing problem.When we come missing very little. down in wavelength to 7 metres, I deprecate the word " fasc- where the technique of reception ination'as applied to wireless certainlyundergoesagreat reception but there is no doubt change,one may expecta that the possession of a receiver revival and intensification of which will pick up these extra- mumbo-jumboism. The Tele- ordinarily short waves which sounder, however, is likely to have all sorts of peculiar pro- nip this in the bud.In the pertiesoftheir own brings case of short waves I waited back an enthusiasm which one until programmes were good has not feltsince 1922.The enough and strong enough and fascination is greatly increased numerousenoughto make by the fact that the programme short-wavereceptionworth- when obtained is se excellent while.The situation, however, and free from fading and so loud as regards the ultra -short-wave and clear.But allthe time reception of television sound one knows that these ultra -short is entirely different.The pro- waves behave more like light gramme is there, it is excellent The theoretical circuit of the " Tele-Sounder."It will be seen that two spare waves travelling in straight lines terminals (A, and A.) are included.These are to enable experiments with different in quality, the signals are strong sothat AlexandraPalaceis aerial -coupling methods to be carried out.On the ultra -short waves smooth and there is no fading.Also, reaction wi h a complete absence of " back -lash " and threshold howl is essential. really shiningitswaves into (Continued overleaf) the homes of London. That is achieved in the " Tele-sounder " by employing resistance control. This does not mean that buildings ob- struct the waves ; you can put up an aerial in your own room or even do without an aerial and still pick up the signals, although if you are in a steel building the position may bemodified.Theordinarycon- structor, however, does not live in a steel house, and he will get excellent results on the television sound programmes. I have scoffed at the attempt to create a mystery of the ordinary short wavelengths, but when we come down to the ultra -short bands, the purely technical engineering problems are of extreme interest to anyone experimentally -minded.There is a great field for experiment here, and amateurs have wonderful scope because they have a good, reliablesignal there on which to experiment. A Complete Finished Instrument But, as I have previously explained, it is not my work to offer experimental designs. The Tele-sounder isa complete finished instrument which will give you the tele- vision sound programmes with reliability and with excellentresults.Butthere are many interesting experiments you can performwiththeaerialarrangements. There are all kinds of odd bits of wire The sheet of aluminium used for screening the pane, can o, clearly seen in this photograph.The object of this screen L which you can sling up inside a room, o avoid any hand -capacity effects when tuning or applying dangle outside the window or fix to your reaction, 354 Popular Wireless, December 5th, 1935.

DAar-Zg,. A0'40 CHILDISHLY SIMPLE TO OPERATE

(Continued from previous page.) the use of a small condenser, in the Tele- four sockets.The grid pin is omitted in sounder, there is no advantage to be gained order to isolate the grid socket. A ter- thereisno problem of selectivity, and by having a slow-motion drive.Nor is minal fitted to the side of the adaptor is there is not a large variety of stations. theretheslightestdifficultyeitherin connected to the grid socket.Also there On theother hand, thereareother picking up the television sound programme is a terminal connection to each valve problems of design.Reaction, for example, or tuning it in accurately when it is once pin. The three wires from theTele- and the choice of components.But actually picked up.In fact, as regards handling, sounder are taken to the two filament the Tele-sounder is much easier to operate the Tele-sounder is very much like the most terminals on the filament adaptor, and than any other sort of receiver.(It has primitive valve set being used to pick up the lead also goesto the Tele-sounder only one tuning knob and one reaction knob.) the local station.This is in no way an from the grid socket on the valveholder it is, when used in conjunction with an exaggeration, rand I assure you that the adaptor.A,l1 you do to receive the television ordinary receiver, a " det.-and-two-L.F." operation is very much simpler than on sound programmes is to take out the last receiver. We are therefore back at the any other waveband. Immediately remove valve but one on the main set,i.e. the stage of the most primitive receiver of from your mind, therefore, any feeling that so-called " first L.F. " valve,insertthe broadcasting. T h e valveholder adaptor in reasonisthatthis the empty valveholder arrangement is notPROVIDES AN ENTIRELY NEW ALTERNATIVEPROGRAMMEand then replace the only good enough but valve in the sockets very good indeed. ofthevalveholder The question of selec- adaptor.The setis tivity does not arise then switched on and and may not arise for tuning carried out on years. The receiver the Tele-sounder. No of television sound is attemptis made to really aone -station tune on the main re- set and this also adds ceiver,becauseonly greatlytothesim- the last two valves of plicity. But please do this are actually em- not imagine that ployed.The Tele - because the Tele- sounder may be used sounder is so extremely on theS.T.3 00, simple to build and so S T . 4 0 0, S.T.600, childishlysimpleto S.T.700, Centurion, operate that there is and S.T.800. In fact, no design work in it. with any set having The work has simply two triodes at the end, been already done for coupled by anL.F. you, and therefore you transformer. Probably have no worries your- it would work with self. any battery set if de - coupling is adequate. Reaction Points The rather unusual Quite Automatic way of obtaining There is no question adjustable reaction, of switching on the by altering your resist- Tele-sounder because anceintheanode it isautomatically circuit, isone of the switched on when the departures from usual valveholderadaptor practice.It is highly ispluggedinto the desirable to have ex- Builders ofthe " Tele-sounder " will have an entirely new source of entertainment available. The main set.Similarly, ceedinglysmooth television sound programmes come through at excellent strength and with very good quality. when the valveholder reaction and to arrange adaptor is pulled out, that changes in reaction do not alter the these waves are difficult to receive.With the Tele-sounder is disconnected from the tuning.Nor must there be any suspicion the Tele-sounder, they are simplicity itself. accumulator. of threshold howl or "backlash." The normal aerial used on the main Perhaps the most astonishing feature of What the " Tele-sounder " Is receiver will have been connected to the the Tele-sounder is that there is no slow- What is the Tele-sounder ?It is really A 1 terminal of the Tele-sounder ; usually, motion condenser.The omission of any a separate detector stage with its own however, such good results are obtained on such arrangement at first seems fantastic. tuning circuit and reaction control.It uses simple short lengths of wire even in a Since a slow-motion drive is necessary on a Mazda L.2 valve as detector, although room, that you will probably have such a the S.T.800 when receiving short waves of other valves may be found suitable. Those small aerial permanently connected to the very much greater length, surely when we who built the S.T.800 can simply use the terminal A 1 of the Tele-sounder. come down to 7 metres an even slower detector valve in that set, and plug it into The paneloftheTele-sounderonly motion drive is necessary ?This is quite a the valveholder of the Tele-sounder.No measures 8 in. by 6 in.and everything is fallacy.In dealing with the question of extra valve need be purchased. There is an mounted in Uni-plane fashion on this panel. selectivity on short waves I explained in H.T. lead from the Tele-sounder which There are two little side -pieces to support my S.T.800 article that many people believe goes to a point on the high-tension battery, the panel so that the construction follows that short waves were selective in them- while there is also a G.B.- plug which goes exactly that of the S.T.800.Needless to selvesin some mysterious way and I into the bias battery.These connections say, this arrangement is exceedingly cheap, pointed out that the fact that a station may be left permanently in circuit.There while looking quite presentable and even came and went over a very small movement is also a valveholder adaptor. Thisis attractive without any further alteration. of the condenser did not mean that the connected by three wires twisted together, But if you wish you can omit the side - set was selective.I also pointed out thatwhich gointotheTele-sounder. This pieces and simply screw the panel on to a the rate of movement and the size of the valveholder adaptor is really like another box -like frame without a bottom.In this condenser were all-important factors.By valveholder and consists of three plugs and (Please turn to page 356.) Popular Wireless, December 5th, 1936. 355

PILOT AUTHOR KIT 1 S.T.800 BATTERY FINISHED INSTRUMENTS VERSION 0DELIVERY FOR XMAS OR CASH REFUNDED S.T.800 We give a definite guarantee that all cash orders for S.T.800 Finished Instruments Ays Carriage received after theappearance of this advertisement, will be delivered for Xmas or KIT 67s cash will be refunded in full ScottPeto-Scott -Taggart, S.T.800 are Finishedassembled Instruments and exactingly include tested all first by highlyspecified skilled parts Radio as used engineers, by Mr. John and Complete Kit of Components exactly as FIRST absolutely READY TO PLAY. The specially designed cabinets for these instruments are hand specified and used by Mr. John Scott -Taggart, French polished, and are supplied complete with extension spindle for sidecontrol. Each with Konectakit (Gratis with Complete Kit) but cabinet will accommodate all necessary batteries and accumulators or eliminator. Every Peto- lesswanderplugs,accumulatorconnectors, Scott Finished Instrument is AERIAL TESTED ON ACTUAL BROADCASTING. valves, Extractor Kit, Cabinet and Speaker. -S.T.800 VERSION CONSOLETTE MODEL-- KIT "s"Carriage Paid£4:14:0 'As for Kit " A," but including set of 4 FIRST specified valves only, less cabinet and speaker, etc. Exact to Specification.Complete KIT 16 eT,,As for Kit "A," but with valves and with FOUR FIRST SPECIFIED Pets Scott S.T.800 Table Cabinet only, less sneaker, etc.Carriage Paid £5/11/6. DEMONSTRATIONS Valves.Including Pete -Scott Type KITi Cr! n As for Kit'' A," but with valves and Pcto-Scott Consolette Cabinet only, with dailyat77,City 101 matched speaker and walnut speaker baffleandbat toryshelf,lessspeaker.etc. Carriage Paid £6/910. Road, London, consolette cabinet (illustrated on left), ttrr Kit " A." but with valves and E.C.I (Clerkenwell KIT "CLL" AsPeto-Scott. ConsulateCabinet, Type 5911); 62, High less batteries.OVERALL DIMEN- bathe,lessspeaker,etc. " LL "only,withspeaker Holborn,London, Carriage Paid £611116. W.C.I (Holborn SIONS : Width 20in. ; Height If Extractor Kitisrequiredwith anyofthe above Kitsadd £1/410 to Cask Price. 3248). 24in. ;Depth 121 in. 4,11 theabovekitsarerequired completewith P., wanderplugsand 2 accumulatorconnectorsas specified, ADD 1/9 to Cash Price. CASH E8 PRICE ° 1 9 6

S.T.700 to S.T.800 BATTERY CONVERSION KIT S.T.800 VERSIONTABLE MODEL COMPLETE SET of parts necessary to con- vert your S.T.700 to the all -wave S.T.800, exactlyas recommended by Mr. Scott - Taggart. Built exactly to Mr. J. Scott-Taggart's Comprising: B.T.S." Quad -wave" tuning unit. aerial balancer condenser, turret switch, B.T.S. H.F. choke, 3 b -wattresistors,5,000ohms,and 2 specification by Peto-Scott's expert tech- l-megohni 2micafixedcondensers,.0001and 0005-nefd. Carriage Paid 33/6. nicians. Completewith FOUR FIRST SPECIFIED valves and Pete -Scott Walnut tablecabinet(illustratedon]eft),less A.C.MAINSS.T.800 KIT 66 A I/Complete kit of components as FIRST batteries. OVERALL DIMENSIONS : SPECIFIED and used by Mr. J. Scott - Taggart,includingPoto-Scottready -drilled and polished walnut plywood panel, ready -drilled terminal Width 18,1 in. ;Height 141 in. ;Depth 12 in. strips, aluminium brackets, mains lead,nuts and bolts,less valves, cabinet, speaker and Extractor Kit. Carriage Paid£9 :16 :6 KIT 13."As for Kit " A," Int including set of 3 specified valves only.Carriage Paid £1111510. PRICEE7:2:6 Mr. J. Scott-Taggart's 5.1.800Type"Ir MODEL TELE-SOUNDERBATTERY VERSIONA.C. MAINS VERSION KIT "A"'g_aasrrhiaagree.°P.aEiCI 38'6 Exact to specification. CompleteExact to Specification. Com - Complete hitof parts, as first speci- with FOUR FIRST SPECIFIED plete with THREE FIRST fiedbyMr.J.Scott -Taggart,and shownbelow,includingaluminium valves, Pete -SeottMatched de Luxe SPECIFIED valves and speci- screen, terminal strip,ready drilled and polishedpanel,andtwo side - speaker Type 102 and walnut con- fied W.B. speaker in Peto-Scott pieces, less valve. soiette Cabinet Type LL (as illus- Consolette Cabinet Type LL (as Balance in 8 monthly payments of 4/6. trated on right), less batteries. illustrated on right). PARTS CONTAINED IN KIT "A." Any pars available separately.Orders over 10;- sent post free CASH PRICEE9.15.0 PRICE£19:10:0 1 Peto-Scott " Tele-sounder " Structakit,s.d. comprising:-Ready drilled aluminium screen, * PRICED LIST OF PARTS AND FULL DETAILS ready drilled terminal strip, ready drilled and OF PETO-SCOTT S.T.800 STRUCTAKITS, ETC., polished walnut plywood panel, 2 polished side AVAILABLE ON REQUEST. 0 4,70; STENTOYOURIAN 1 B.T.S. 000025 tuning condenser ... 3 FOR 1 J.B. .00005 baseboard trimmer ... ..1 0 RECOMMENDED) ORDER FORM' 1 Lissen 00005-mfd. mica condenser ... 6 for the 2 Dubilier fixed condensers ...... 2 6 1 T.C.C. 5 tubular condenser ...... S.T.800 k PETO-SCOTT CO., LTD., 77 (P.W.8), City 1 Eddystone 4 -pin valve holder ...... 11] 1 Cg MODEL 37S. Amazing reproduction Road, London, E.C.1.Telephone: Clissold 9575. 1 Varley Niclet L.F. transformer ..7 6 Providedby newmagnetandcx 216 Weal End: 62t P. W.8), High Holborn, W.C.1. 2 Dubilier L -watt resistors ... 1 0 potentialmouldedcone. Microlode DOWN Telephone: Holborn 3248. 1 Erie 50,000 ohms potentiometer ::: ...5 0 matching device. 1 Colvern " Tele-sounder " coil 2. Cash or C.O.D.Carr. Paid £212/0, Pleasesupply 1 B.T.S. short-wave choke.., ... ::: S or 216 down and 11 monthly pay- 2 Bulgin knobs, type K20 ...... 9 ments of 4/-. 1 Bulgin valve holder adaptor ... - 2 6 MODEL 37J. With the new exclu- i CI I enclose £ s. (1. M.O.!P.O.,'Cheque. 4 Belling -Lee type R terminals .10 siveStentorianfeatures. Wonderful 2 Belling -Lee midget wander plugs ...... 4 iinprovement in volume and realism Connecting wire, screws,flex...... 19 ofreproduction. Perfectly matches anyreceiverasprincipalor extra NAME Eft " A," Cash or C.O.D. Carr. Pd. £1 18 6 speaker. Cash or C.O.D. Carr. Paid £1/1216, ADDRESS KIT"B" As for Kit " 771717 specified or 2/6 down and 11 monthly pay- svalve.Cash or C.O.D. Carriage Paid £2/313, or 5/- I ments of 3/.. a down and 9 monthly payments of 4/9. Any W.B. Chassis or Cabinet Model available EST. 1919 on attractive Easy Terms. L an IS in I= ES I. a a a OM MI NM ======MIR 356 Popular Wireless, December 5th, 1936.

(Continued from page 354.) CIRCUIT EVOLUTION There are two essential requirements in obtaining reaction on these very short case, the complete unit will look rather wavelengths. One isthat the reaction like the Triple Extractor box. shall not be susceptible to hand -capacity

Those who have seen the Tele-sounder effects and the other is that the reaction next to the S.T.800 have been amused to must not alter tuning. Of course, there are notice the similarity of construction, the C3 other factors ;for example, reaction must Tele-sounder looking like a baby set beside be very smooth, there must be a complete its mother.But even though the Tele- absence of hysteresis or " backlash," and

sounder is so very small and is so simple to there must be no threshold howl. All these

construct, the benefit of Uni-plane construc- . . II factors govern the method whereby the tion remains and adds considerably to the ?- reaction isobtained, and I am recom- attractivenessofthedesign fromthe mending the use of a fixed reaction con- practical standpoint.The whole outfit can denser C2, as shown in Fig. 2, and the in- be constructed in a couple of hours. :Lg sertion of a variable resistance R2 (having a maximum value of 50,000 ohms), inserted Simple in Every Way in the anode circuit of the valve, thereby I am giving a rapid construction guide controlling the H.T. voltage. We all know as I anticipate a very considerable popu- that, as we increase the H.T., reaction in- larity for this unit and I wish it to appeal Fig. 1.-The figures 1, 2 and 3 show the evolution of the " Tele-sounder " circuit. creases, and the present arrangement is to those who have no previous experience First of all we exceedingly effective. of constructing sets.There are many who have a normal reaction circuit. alreadyhavebatterysetswhich they For Batteries or Mains Units themselves have not built, and there is no reason why they should not have everything The condenser C2 need not be absolutely made as simple as possible when they come accurate. Needless to say, you must be able to build the Tele-sounder. The short-wave to control the reaction on the resistance choke and the actual coil can very easily be R2, but this can always be obtained by made by the home constructor, but they can suitably adjusting the high-tension voltage also be purchased ready-made.Details of tapping.This system serves an accidental of the coils is given on page 352. additional purpose in that the resistance R2 It will be noticed that a tapping is taken also provides a means of decoupling this on the main tuning coil.This tapping is valve. When the Tele-sounder is in use we caused by actually soldering a wire on to really have a three -valve set in which the firstvalveisthe detector in the Tele- the coil.If you are building the coil yourself sounder itself and the other two valves are . you must do thissoldering,as any other kind of joint may lead to all kinds of trouble. the last two valves in the main receiver. I know of many constructors who will not Fig. 2.-Reaction control by vo tage variation on Old readers will be aware that every set theanodeavoidshand -capacityeffectsand I have designed will 'operate either on heed this advice, but having offered it I prevents reaction affecting tuning. batteries or mains units. The same applies decline further responsibility.You will to the Tele-sounder, and it may be built with notice I have used a large tubular condenser every confidence by those who are now work- of 0.5-mfd.It looks rather cumbersome ing their sets off mains units.There is no but it was not chosen for any technical fear of motor -boating or distortion. reason but simply because it serves as an Fig. 3 shows in elementary form the three - excellent former on which to wind the main valve outfit obtained by adding a Tele- coil !The constructor is therefore saved sounder to an existing battery set.It will any bother in hunting for some tube of be seen that the circuit consists of a detector suitable diameter. with reaction followed by two stages of low - A sheet of aluminium is used for screening the panel so as to avoid any hand -capacity frequency amplification.It will also be effects which would add to the difficulty seen that there are two L.F. transformers. of tuning or applying reaction.It will be Thisis not usual practice butIhave appreciated that on these very short wave- Fig 3.-The circuit " in elementary form " of adopted it in order to gain greater sen- the " Tele-sounder,"addedtoanexisting sitivity.Naturally, my first experiments lengths tuning is easily upset unless such battery set. involve the useofresistancecoupling, precautions are taken. which is rather cheaper.I find, however, Reaction is applied in much the same way that although itis perfectly satisfactory as in an ordinary broadcast receiver-that METHODS OF FEED in many cases, yet the sensitivity is not is to say, there is a reaction coil coupled to such that I could whole-heartedly recom- the main coil, and this reaction coil is fed mend the Tele-sounder for use in all con- through a condenser from a reaction choke. ditions and with any kind of aerial.There Insteadofusinga reaction condenser, is no question about signal strength being however, for varying the reaction, the re- anything like that of a foreign station. action condenser is fixed and the reaction is You get full local strength on the Tele- altered by varying the voltage on the anode sounder,and even without anyaerial of the valve.This is done by including a at all quite good results are obtainable. variable resistancein the anode circuit It is simply another example of my keen- of the valve. (a) (b) ness to provide a very large margin of safety The Coil Tapping when it comes to sensitivity.This has The evolution of the Tele-sounder may be characterised all my sets since the S.T.400, seen from Fig. 1, Fig. 2, and Fig. 3.Al- which was the first really popular four.. though a continuous coil L1 L, is wound valve set in recent years. with a tapping M taken from a p'bint on it, yet actuallythisapparently continuous Obtaining Increased Sensitivity coilis really two coils, one L1 being the Although the use of two L.F. transformers tuning inductance while L2 is the reaction isnot necessary andisthereforenot coil.In Fig. 1 a valve is shown being used adopted on medium and long wavebands, to produce a reaction effect. A short-wave yet the increased sensitivity is very well air -cored choke Z is included in the anode worth while, and the quality of reception circuit of the valve, while the variable (c) (d) (e) and stability remains excellent.Incident- condenserC2 controlstheamount of ally, there is none of the risk of distortion Fig. 4.-Different methods of feeding the tuned due to grid circuit choking which may some - reaction current which is fed through the circuit are illustrated here, and may all be used reaction coil L,. with the Tele-sounder. (Please turn to page 367.1 Popular Wireless, December 5th,1936. 3:57 POLAR SPECIFIED forthe S T 800

ALL -BRITISH CONDENSERS

ThePOLAR SPECIAL 'No. 2' Made of aluminium. Ball Bear- ONE 0005 ings throughout. Supplied with REQUIRED special Knob andPointer(as S.T. Specification). PRICE..5 /6 alsospecifiedfortheEXTRACTOR UNIT

WMCRCVE & ROCERS LTD. POLAR No. 4 CONDENSER Direct drive, rnada THREE '0005 REQUIRE) 188189, STRAND, LONDON, inaluminium with(with Knob as specified) W.C.2. Phone: Temple Bar 2244 brasspillars. Ball Works :Old Swan, Liverpool. bearings. PRICE EACH415 Condenser only 4i- 553 one Ideal Xmas sift Book for I3ops

Conquest of the AirSPECIFIEDFOR THE in Picture and Story Here is a gift book that will delight boys.There Boththebattery and is a thrill on every page mains model S.T.800 S.T.800 as the wonderful story of useT.C.C.condensers because Mr. John Scott - BATTERY MODEL modern flying is unfolded. Taggart insists upon Each Packed with interesting dependabilityin every I 004-mfd. condenser T.C.C. type M 1/- component.Depend. 1'0001 -mid. condenser T.C.C. type M 8d. factsand photographs, ability comes only from 2 '0005-mfd. condenser T.C.C. type M 9d. the book reveals the con- specialised experience "I I-mfd. tubular condenser T.C.C.type 250 1/4 quest of the air so that and (*Incorporated in the coil unit.) every reader can under- T.C.C. HAVE MADE CONDENSERS AND A.C. MAINS MODEL stand why great machines CON DENSERS Each fly, and many other in- 2 0'5-mfd. tubular condensers T.C.C. type ONLY FOR 28 YEARS 2/- teresting things about 2 0'1-mfd, tubular condensers T.C.C. type them.There are scores 250 1/4 ofpictures, and a fine 3I-mfd. Paper condensers T.C.C. type 50 2/6 1 50-mtd.Electrolytic condenser T.C.C. colour plate. 2/3 2 *8-mfd. Electrolytic (wet) T.C.C.type 802 6/ - The FOR THE TELE-SOUNDER MODERN BOY'S NEW I .5 tubular condenser TC C ,?e,250 ... 2/ - THE TELEGRAPH CONDENSER COMPANY LIMITED BOOK OF AIRCRAFT WALES FARM ROAD, NORTH ACTON, W.3 On Sale at all Newsagents and Booksellers 61- 1354 3:18 Popular Wireless, December 5th, 1936 THE "TELE-SOUNDER" RAPID CONSTRUCTION GUIDE ( A) Drill panel according to front of (4) Join C terminal of coil to terminal (17) Join one end of rubber -covered lead panel diagram. (nearer bottom of panel) of -0001-mfd. of triple -plaited flex lead to G terminal (B) Drillterminalstripaccordingto fixed condenser. of Varley Niclet, and join other end to diagram. (5) Join B terminal of coil to M terminal G terminal of valveholder adaptor. (C) Fit terminals to terminal strip. of tuning condenser. (18) Join one end of black lead of triple - (D) Fit a wire (18 S.W.G. tinned copper) (6) Join B terminal of coil to F terminal plaited flex lead to F terminal (nearer top to Al terminal.This should be 3 inches (nearer top of panel) of valveholder. of panel) of valveholder and join other end long from the point where it leaves the (7) Join terminal (nearer top of panel) to F- terminal of adaptor. terminal. of -00005-mfd. grid condenser to G terminal (19) Join one end of red lead of triple - (E) Fit a wire (18 gauge tinned copper) of valveholder. plaited flexleadto F terminal (nearer to E terminal.This should be 31 inches (8) Join1-meg.gridleakbetween bottom of panel) of longfrom thepoint G terminal and F terminal (nearer bottom valveholder, and whereitleavesthe of panel) of valveholder. join other end to terminal. (9) Join F terminal (nearer top of panel) F-)- terminalof (F) Fit terminal strip to aluminium screen by means of a i-in. adaptor. to side -piece as shown No. 4 round -head brass screw and I in. by (20) Join one end in diagram. 1 in. brass washer. (10) Join F.terminal (nearertop of al; panel) of valveholder to terminal nearer Mrolfiln-M3%Voi-V-2 top of panel of -0003-mfd. fixed condenser. (11,) Join 0-5-mfd. tubularfixedcon- Both side -pieces are The terminalstrip is exactlythesame mounted on the side -piece denser between terminal (nearer top of and are cut to these as shown in this diagram. panel) of -0003-mfd. fixed condenser and dimensions. H.T.+ terminal of Varley Niclet. $106Wlikg4-f4M-4`.,kAVALI (12) Join terminal (nearer top of panel) kr,.:MAK-11:1MAC1A6--if43 of -0001-mfd. fixed condenser to A terminal ZieeneacrolrVde- of valveholder. (G) Cut aluminium screen to size and (13) Join centre terminal of 50,000 -ohm of a rubber -covered flex lead to G.B. - drill holes according to diagram. potentiometertoH.T.+terminalof terminal of Varley Niclet, and fit G.E.- (H) Place aluminium screen on back of Varley Niclet. wander plug to the other end. panel so that holes in panel register with (21) Join one end of another rubber - holesinscreen.Now fittuningcon- TERMINAL STRIP DETAILS covered flex lead to right-hand terminal of denser and 50,000 -ohm potentiometer. 50,000 -ohm potentiometer, and fit H.T.± components to back wander plug to other end. of panel, using " blue -print " drawing as guide to positions :aerial coupling con- rt Fit Side -pieces. denser, -00005-mfd. grid condenser, valve - (K) (22) Join free end of wire on E terminal holder, -0003-mfd. fixed condenser, Varley 2'-eroz Niclet, 0001-mfd. fixed condenser. 1 I r of terminal strip to M terminal of tuning The set is now ready to be wired.The P67 condenser. following numbers are those of wires so (23) Join free end of wire on Al terminal marked on the" blue -print "drawing. of terminal strip to terminal (nearer top of Actually this drawing is not a blue -print *6*ElsOnAZ panel) of aerial coupling condenser. but apart from the colour itis equally The terminal strip consists of a piece of ebonite 4 ins. x 11 ins. in which six holes are drilled ; useful. four for the terminals and two for the Axing screws. VIIK-M=M-APX--:§7-AMmm-m * (1) Jointerminal(nearerbottomof (14) Join 30,000 -ohm resistor between A handsome celluloid dial for the S.T. 800, panel) of aerial coupler condenser to F H.T.d- and P terminals of Varley Niclet. similar to the card dial issued in Popular (15) Join P terminal of Varley Niclet to Wireless but revised up to a later date L terminal (nearer top of panel) of tuning ofprinting,isobtainable for2s. 6d., a condenser. terminal(nearerbottomofpanel)of post free, from Celluloid Printers, Ltd., (2) Join same terminal of tuning con- -0003-mfd. fixed condenser. Kingston By-pass Road, Surbiton, Surrey. (16) Join H.F. choke between terminal denser to terminal (nearer bottom of panel) AThis is the only dial approved and checked of -00005-mfd. grid condenser. (nearer bottom of panel) of -0003-mfd. by the designer of the S.T.800. (3) Join F terminal (nearer bottom of fixed condenser and terminal (nearer top es panel) to A terminal of coil. of panel) of -0001-mfd. fixed condenser. wxgv-3-7,4tm-mt,Italwro..v4 8"

7" fi

On the left are the drill- ing details and dimen- sions for the aluminium screen which is half -an - inch smaller all round than the wooden panel, details ofwhich are given on the right. Note the recessing onthe panel for the reaction control fixing nut. _ W.e.a.vy - 376Maaafa,,4-"Skal; eII78ce"."" f,

/ii ems"ems" of /0a.. -use 9,-,ze.--xceons Q.eze.te Cteezenuzucen fc/e.aesez/r j'4" Duck Popular Wireless, December 5t11,1936,

By H A, Dossett R. JOSEPH HOBIDAY, sole repre- The round, pink face of Mr. Hobiday when Jerry Franter and his bosom friend, sentative of law and order in the graduallyassumedabeautifulpeony Bob Amblett, joined forces one night for village of Fuzleclene, made his way shade. the foray into Farmer Gator's rickyard. slowly up the flagstoned path which led " If only I could catch you once in the With much stealth and two large and to the cottage door of Jerry Franter and act, Jerry Franter, something'd be tore off dirty sacks, they successfully negotiated eyed the closed portal much as a cat might your back," he promised darkly. " An' now the holly hedge which bordered the farm look at a well-known but, so far, unfruitful you listen to me Not so very long ago, outhouses and, bending double, padded mouse -hole. Farmer Gator lost a sucking pig. oil softlyin the direction of the rickyard, He would havesacrificedpromotion don't remember that, I suppose ? " where they fondly imagined their Christmas to get the better of Jerry in a battle of wits, Jerry nodded solemnly. dinner to be awaiting them, but, as he gloomily reflected, it was doubtful " Ido,"heansweredcomplacently, Suddenly, Jerry, who was in the lead, if he would ever succeed.With a large fist " Rats, that's what it were. Very intelligent stopped abruptly in his tracks. he banged thunderously on the door until rats is.I reckon a gang of rats got that "Hear anything, Bob ? " he whispered Jerry opened it. hoarsely. Mr. Franter looked up at theAm-v-amnnr.;:nxonnrimnvIsnnomm-mon-or--..-nlk The reply of Mr. Amblett, who figure and grinned. had notexpected the sudden "'Morning,Joe,"he said . . . When Jerry Franter, village poacher - halt, and had, in consequence, run cheerfully. " Come to wish me a his left eye on to Jerry's elbow, Merry Christmas" in -chief, hit on his bright idea for getting a was personal, but not relative. The constable snorted through free Christmas dinner, he felt it was already " Don't make such a row about his yellow moustache. as good as his.But he had reckoned without nothing,"growledJerryun- " No,Ihaven'tbecauseI sympathetically." I thought I don't ! " he stated brutally. " I've Fuzledene's sole representative of law and heard a dog's chain rattle." just come to warn you." order, P.C. Hobiday . . " It's your own brains,"re- Jerry's little black eyes, bright torted the aggrieved Mr. Amblett. and mischievous as a jackdaw's,WAKAPAC4AWZAMIMAMSAMAMAMAtAlarTaaAt " They've gorn rotten and dried twinkled. up like a cob -nut in its shell." " Warnme,Joe ! " he exclaimed little pig.Rats is very partial to pork." Mr. Franter ignored the thrust. anxiously. " What about ? Is them " An' I suppose it was rats that dragged " Where's that there Rover ? " he asked poachers and chicken thieves loose again ? a couple of geese out of his rickyard just anxiously. If so, I must keep a close eye on my birds. afore Michaelmas, and swallowed 'em whole, Same place," replied his companion I've got some valuable stock in my runs feathers andall,eh ? "thepoliceman laconically. " Locked up in the wood- at the moment." demanded truculently. shed with a bone as big and as 'ard as Considering that Jerry was the cleverest Jerry screwed up his eyes and tapped old Gator's 'end." poacher and farmyard snatcher for miles his Stubbly chin with a dirty forefinger. Jerry chuckled." How that dog do love around, and that the " valuable stock " No," he announced judiciously." I bones !But I could 'a swore I heard a consisted of two aged black hens confined wouldn't say it were rats had them geese. chain clink, Bob." behind a yard and a half of rusty wire Foxes more like. Nothing foxes fancy more Mr. Amblett shifted impatiently. " You're netting, the speechless indignation of Mr. than a nice fat goose." scar't of old Hobiday, that's what's the Hobiday was understandable. The policeman held up afistlike a matter with you. Why don't you get a " It ain't your prize poultry I'm worrying bunch of twisted, well -scrubbed carrots. move on ? Do you want them turkeys to die about," he retorted, with heavy sarcasm. " I'd like to give one of those rats or of old age ? " " It's Farmer Gator's." foxes a good sock on the jaw with that ! " But the acute ears of Jerry had not been " Why him specially ? " demanded Mr. he said belligerently." And p'raps I will mistaken. Franterindignantly. " I'veas much before l've finished with 'em ! " Rover, unworthy watchdog and lover of right to police pertection as he has ! " " Rats is very clever, knowing animals," beef bones, had once again been bribed into The pillar of the law drew a deep breath. Jerry averred, shaking his head." So is betraying his trust, and all should have " Now you listen to me, Jerry Franter ! foxes. I doubt ifyou'll ever get near bben well for the invaders.That it was Every livin' soul in Fuzledene village knows enough to 'em for that ! " notso,was due entirely to Scotty, a you for the craftiest, cunningest rascal and " We'll see ! " said P.C. Hobiday. "Any- diminutiveterrierrecently acquired by thief in the place." way, you take a hint !Remember, I've Farmer Gator for ratting. " Libel !That's what that is! " inter- warned you ! " Neither Jerry nor Bob was even aware ruptedJerrysharplyand withgreat He rearranged his helmet and, without that Scotty existed until he suddenly shat- confidence." Libel-and maybe inflamma- a word of farewell, turned purposely in tered the calm of the cold peaceful night tion of character ! Pity there ain't no the narrow porch and strode with even, with a riot of short, staccato barks. witnesses. Icould have your uniform deliberate steps down the flagged pathway At the very first yap, Jerry and Bob tore off your back for that IDrummed out to the gate. turned like one man, and like one man of the police, that's what you'll be ! " It was about a week before Christmas (Continued overleaf.) 360 Popular Wireless, December 5th, 1936.

I from Jerry Franter's cottage, pushing a ContinuingRADIO BARRAGE I sugar -box mounted on four wheels. Within this improvised vehicle reposed the radio made for the hole in the holly hedge.Like Mr.Franter.Hewasobviouslynot set. Half -wayalong Pondmere Road, one man they reached it ;like one man interested. His bright little eyes were fixed P. -C. Hobiday, dressed in civilian clothes they dived into it ; and like one man, they with an intense stare on the old battery and hidden by the shadow of a sturdy oak, stuck. radio set in the corner of the room, and watched them go.Then he made his way Old Farmer Gator flung up his bedroom he had no time for argument. carefully into the back garden of Jerry window, and two seconds later flung a Mr. Amblett, surprised at such unex- Franter's cottage and disappeared in the charge of spraying duck -shot at the dim, pected acquiesence, glanced at the speaker. darkness. rustling hedge.Most of it went wide, but " Goin' into a trance,or something ? " All unconscious of the silent witness, one stray pellet bored viciously into the he enquired, " or just listening for your who according to a well-known schedule scat of Mr. Arnblett's corduroy trousers, brains to start rattling. agen ! " should have been some miles away, the two and he roared almost as loudly as the " Bob,"declared Mr.Frantertrium- conspirators proceeded to put their plan farmer's old gun.Like a horse under the phantly," them turkeysisas good as into operation. spur he leaped forward, taking Mr. Franter ours ! " " I think," said Mr. Franter thought- with him. " I know," said Mr. Amblett." They fully, " that we ought to go to the Rectory The shot from the second barrel merely was last night.Nothing easier 1All we've first, then to the Hall.It'll look better ruined some very pretty holly, because the got to do:is just go an' fetch 'em.That's afterwards." raiders were flat on their stomachs in a deep all ;just fetch 'em ! " " Wot will ? "asked Bobcuriously. and wet ditch. " Now don't you go and get peevish, "The 'all ? " Half -an -hour later the two men faced Bob,"soothedhiscompanion," just Jerry regarded him dispassionately. each other across the embers of a fire in because a stray pellethit you in the " I know you can't help being a fool, the kitchen of Jerry Franter's cottage. trousers.I say them turkeys is as good Bob," he said, " but you needn't advertise Mr. Robert Amblett was sore, meta- as ours." it.That there Hobiday's bound to try and phorically and literally, and he said so in Mr. Amblett nodded approvingly." All trace our movements when he finds the no uncertain terms."'Ow long 'as old right, if you say so, Jerry !I'll wait 'ere birds have flown, so to speak.He must Gator 'ad that terrier ? " he wrathfully while you go an' get 'em.Let old Gator write something down in his little notebook asked." That's what I want to know." use the seat of your breeches for a target, to prove that he earns his wages. Now "So do I ! " Jerry mused thoughtfully. 'stead of mine ! after we've been to the Hall and the Rec- " He very nearly did for us to -night." " We got to use strategy," Jerry stated tory, we go over and wake up old Gator. " Yapping little'ound," Mr, Amblett with conviction." That there Hobiday is At least, you do.Then you come back to snarled." I'd like to wring 'is neck ! " getting artful, and he's beginning to think. my place when you've finished with him. I'd like to wring the necks of a couple I don't like policemen who think. We got Understand ? " of old Gator's turkeys much better," said to outwit him.That's what we got to do. Mr. Amblett nodded his approval. the disgruntled Jerry, "and what's more, I Outwit him ! " " Right you are,Jerry, Let's get will, terrier or no terrier,I wondered why " 'Ow ? " demanded the soured Bob. agoing. ' that fat pink pig of an apology for a police- Mr. Franter walked across to the ancient Mr. Franter, who had spent long and man came all the way up here to warn wireless set, and switching it on turned a lonely hours learning the secrets of his me !He knew all about that little dog. knob.Immediately the room was filled capricious battery set, installed it on the Goading me, he was !Goading me to go with a noise like a colony of vocal cats Rectory doorstep, and connected up the out and get meself shot." being pursued by an express train. huge horn - type loudspeaker.In a few " You mean goading you, so as I could " That'show,"explainedtheproud seconds the instrument was in full blast, go out and get shot," corrected Mr. Am- owner." Reaction ! " and while the quality of the programme blett feelingly. " I don't see it," Mr. Amblett objected left much to be desired, there was certainly " Have it your own way, Bob," agreed stubbornly. nothing to complain of on the score of " Of courseyou volume. Halfadozenold-fashioned don't," said Jerry im- " waits " could not have made more noise. patiently, " but you The Rector beamed on them, compli- canhearit,can't mented them on their adaptation of modern you ? " invention to old-world custom, and dis- " So can all Furzle- missed them with his blessing, two cups of dene,I should coffee, some seed cake, and sixpence. think ! " Bob agreed "ell," said Mr. Amblett philosophically grudgingly. as they pushed the home-made barrow up " Sit down, then," the hill,a tanner's a tanner ! " invited Mr, Fra,nter, " The Hall " was glad to purchase im- " andI'lltell you_ munity from the onslaught of the raucous exactly what we got loudspeaker for half-a-crown and two tan- to do." kards of ale, and then the two " waits " " You can tell me, made their way to their real objective-the if you like, Jerry," farmhouse of Mr. Gator. agreed Mr. Amblett, The farmer, who was in bed and asleep, " but wild 'orses was suddenly jerked into full and pal- wouldn't make me pitating wakefulness by an eldritch shriek of sit down." blood -curdling intensity, followed by a loud The nightbefore series of startling hoots. Christmas Eve was He was a man of hasty temper and quick still and frosty, with decisions.The last pitiful wailing had just bright starsglitter- died down to a fitful moaning, when he ing in a dark velvet appeared at the bed -room window with the sky.At nine -thirty trusty shotgun in his hand, and murder in the two men emerged his heart. Mr. Amblett smiled up at him disarm- ingly. "I'm sorry, Mr. Gator," he explained Farmer Gator was a man of hasty temper and quick placatingly,but something seems to have decisions.The last pitiful gone wrong. with the works." wailing had just died down to a fitful moaning, when The farmer glared at him out of puffy, he appeared at the bed- blood -suffused eyes. room windowwithhis " Something'll go wrong with your works trusty shotgun in his hand, and murder in his heart. (Please turn to page 368.) Popular Wireless, December 5th,1936. 361 "P.W." SHORT-WAVE STATION LIST Wavelengths and other details of many of the stations you con hear on your short-wave receiver

Wavelength. Station. Call -Sign. Power. Wavelength. Station. Call -Sign. Power. 3-93 W 8 X K 40 31.07 Lisbon C T I AA 2-5 i. yy Pittsburgh 3.93 Daventry G S J 10 3113 Rome 2 R 0 25 3.94 Wayne, New Jersey W 2 X E I 31.27 Radio Nations H B L 20 3.97 Daventry G S H 10 31.28 Philadelphia, Pa. W3 X A U 10 5.93 Bandoeng, Java P L E 60 31.28 Sydney V K 2 ME 20 6-86 Daventry G S G 10 3128 Eindhoven P C J 20 6-87 Bound Brook W3 XAL 35 31.32 Daventry G S C 15 6.88 Huizen P HI 23 31.32 Lyndhurst, Australia V K 3 L R I 6.89 Zeesen D J E 5 3132 Buenos Aires L R X 5 10 6.89 Wayne, New Jersey W 2 X E 1 31.35 Millis, Mass. W I X K 9.52 Budapest H A S 3 20 31.36 Bombay V U B 4-5 9.57 Schenectady W2 XAD 18 31-38 Zeesen D J A 5 9-60 Daventry G S P 10 31.45 Zeesen D 1 N 5 9.62 Buenos Aires L R U 5 31.43 Jeloy LKJI 1 9.63 Zeesen D J Q 5 31.48 Schenectady, New York W 2 X A F 30 1.5 9.65 Wayne, New Jersey W 2 X E 1 31.55 Melbourne, Australia V K 3 ME 9.66 Daventry G S I 10 31.55 Daventry G S B 15 9.68 Radio Colonial, Paris T P A 2 12 31.53 Rio de Janeiro P R F 5 5 A 9.71 Eindhoven P C J 20 32.88 Budapest H A T 4 5 9.72 Pittsburgh W 8 X K 40 38.48 Radio Nations H B P 20 9.74 Zeesen D J B 5 39.95 Tokio J V P 20 I 9-76 Daventry G S 0 10 46.52 Barranquilla HJIABB 9.82 Daventry G S F 10 48.78 Winnipeg C J R 0 2 40 9-84 Vatican City H V J 10 48.86 Pittsburgh W 8 X K x0P, 22-00 Warsaw S P W 10 49.02 Wayne, New Jersey W 2 X E I 22.94 Suva, Fiii Islands V P D - 49.10 Medellin, Colombia HJ 4ABE 24-52 Reykjavik T F J 7.5 49.10 Daventry C S L 15 25.00 Moscow R N E 20 49.18 Chicago, Ill. W 9 X F 10 25.23 Radio Colonial, Paris T P A 3 12 49.18 Bound Brook W 3 XAL 35 25.27 Pittsburgh W 8 X K 40 49.20 Johannesburg Z T J 5 25.29 Daventry G S E 15 49.41 Vienna Ezperirnental 0 E R 2 1.5 25.36 Wayne, New Jersey W 2 X E I 49.50 Philadelphia, Pa. W3 X A U 10 25-36 Lisbon CT 1 AA 2 49.50 Cincinnati W 8 XAL 10 GSA 15 25-38 Daventry G S N 15 49.59 Daventry , 25-40 Rome 2 R 0 25 49.67 Pernambuco PRA 8 3 25.45 Boston, Mass. WIXAL 10 49.67 Miami W 4 X B 2.5 P. 25.49 Zeesen D J D 5 4967 Boston, Mass. WIXAL 10 P. 25.53 Daventry G S D 15 49.83 Zeesen D J C 5 25.60 Winnipeg CJRX 2 49.85 Bogota, Colombia H1 3 A B H I.6 25.60 Radio Colonial, Paris TPA 4 12 50-00 Mexico City X E B T I 27.93 Tokio J V M 20 50.00 Moscow R W 5 9 20 28.01 Tokio J V N 20 50.26 Vatican City H V J 10 29-04 Ruysselede, Belgium 0 R K 9 51.28 Maracaibo, Venezuela Y V 5 RMO - P. 29-24 Bandoeng, Java P M N 3 51.72 Caracas, Venezuela Y V 2 RC 1 30.43 Madrid E A Q 20 70-20 K harbarovsk R V 15 20 74,',.m4rommarnmenntvrtors,vvnrovIrotrnnnw",s-nvmme,,,71-2;nnm-mov--nlos

CHRISTMAS AND THE TELE-SOUNDER What better present could you give to a constructor friend than a " Niclet " ? Better still, make yourselfapresentofthiswonderful component. Retnember, itis specified exclusively for the " Tele-sounder " asit was for that record -breaker, the S.T.800. The " Niclet " L.F.IntervalveTransformer (List No. D.P.21) will cost you 7/6. adiey OLIVER PELL CONTROL, LTD., BLOOMFIELD ROAD, WOOLWICH, S.E.18. Telephone: Woolwich 2345. 362 Popular Wireless, December 5th, 1936.

You must oftenhave wondered what sort of life a B.B.C. announcer has. Perhaps you have envisaged it as a fairly easy one, in which a few hours a day are spent pleasantly in introducing performers to the micro- phone, giving out press bulletins, and so on. Well, this, of course, is part of an announcer's job, but he has to do much more than that as you will see when you read this day in the life ofFreddie Grisewood, thewell- Freddie's) are a bit frayed, known London announcer, whose and in need of lunch to settle photograph,incidentally,appears here. them !Most of the cast go along to theB.B.C. canteen,where,too, Freddie is often to be found.But to-

TWELVE hours a day is quite enough I day he's booked to lunch at a famous for any man, but at : West End restaurant, in the grill of which 8.45thealarmringsinthe then while on the way to the seventh floor you can find celebrities of the stage, screen Grisewood household, and life begins for studios meets Brian Michie in the corridors and radio worlds.This is a long -deferred the day. Freddie washes, shaves and roams and talks over a rough outline of the remarks lunch appointment with a friend in the around in his pyjamas. After all, why not ? Freddie will make as compere in to -morrow's City.At : This looks like being a slack day. He's not Variety.At : supposed to be on duty at Broadcasting 12.0-Rehearsal starts.And like most How Freddie Joined Up House till 5.15, but if all goes well will rehearsals there's a great deal of time lost, 1.30-Over a well-done steak they're have time for some tennis practice before and heel -kicking around the studio. Noth- chatting about the old days, when Freddie lunch, and will turn up at Broadcasting ing ever goes to schedule first time. Every- was running a big estate in Oxfordshire, House early in the afternoon to deal with body's remarks have to be cut, altered and and when anotherfriend,Bob Perry, the post.So idly he slips on a dressing - re -timed. For years Freddie has compered suggested that Grisewood ought to take up gown and has breakfast in his pyjamas- and announced shows of this kind. He a more permanent job than running an and baths afterwards !That's a fad of always prefers to announce programmes estate for somebody who would probably Grisewood's which, as a keen sportsman and where there's a human touch.He does soon die.Perry suggested that Grisewood an all-rounder at hockey, golf and tennis, announce the News, of course, with Hibberd. should get a job in London.So more he has never found bad for his system- But he hates having to do impersonal an- fun than in any seriousvein Freddie but very comfortable from the domestic nouncements. It's well past 1.15 before the dropped a note to Peter Eckersley-though point of view, as it enables breakfast to be rehearsal (calculated to last twenty minutes) he couldn't possibly think what job he over early !But to -day, while he's still in is over-and everybody's nerves (except could do at the B.B.C., even if he were his bath, the 'phone rings at : chosen for what was then such a rapidly - growing concern.Through lunch Freddie The B.B.C. Calling recalls the heart -in -the -mouth feeling he 9.30, and Mrs. Grisewood cans from the had when he went up to Savoy Hill for a hall, " It's the B.B.C., Freddie."Where- test in the No. 6 studio-how he was upon, swathed in a bath robe he emerges, eventually picked for the job-and how picks up the receiver and enters into a lonely he felt when he came up to London friendly argument as to whether he'll turn to start the job on that fatal Monday, in to the B.B.C. by midday, so that he can July 28th, 1929. be at a rehearsal of a show in which he's Others with him in the Announcers' taking part as compere. He decides that Room then were Hibberd(stillsenior though, unofficially, there's no compulsion announcer) and Adams, Farrar, Snagge, and for him to give up his morning's freedom many who have since found jobs in Outside (and as, anyway, he won't be away from Broadcasting, in variety and in jobs outside " B.H." till midnight) it would complicate the Corporation. the job of the producer if he's not there to Back from lunch at : read his script and have it timed. So that's 2.50 Grisewood works in the Announcers' that, and he gives up his morning. Bathed Room for an hour on notes, on press material and dressed, you can find him around : he has to write, and on letters which are 10.0 going through the morning papers, only part of the huge postbag a B.B.C. making plans for some carpentry he wants announcer must deal with. Letters, queries, to do at home when there's a minute to gifts, suggestions for songs in.lhe Children's spare, and discussing with his wife week -end Hour, anxious enquiries about that Oxford- holiday plans for herself and their fourteen - shire character " Old Bill," which Freddie year -old daughter. Then, at : portrays so realistically ;they're only a 10.30 he leaves for Portland Place-and quarter of the letters, nearly every one of smiles a cheery " Good -morning " to the which calls for a personal answer.Tea old, familiar people in the Broadcasting comes into the office at 3.30, but Grisewood House vestibule. The doorman has been on works on without a break as he wants to duty since the old Savoy Hill days, when have a heavy tea just before 5.0, before he Grisewood was a new man on the announc- goes into the Children's Hour. At : ing staff, with a terror of the microphone. 4.15-Cecil Dixon comes on the 'phone 11.50-Freddie goes through some papers to know what songs Freddie has decided to in the Announcers' Room, chats with Mr. sing in the Hour, and will he really be Wellington about programme times, dis- able to sing, or will some urgent Empire Enters into a friendly argument as to broadcast or other compel them to fill in cusses the day's programme announcing whether he'll turn up atthe B.B.C. by mid- arrangements with Stuart Hibberd, and day . . " (Please turn to page 364.) Popular Wireless, December 5th,1936, 363

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coffee in the canteen.That's how pro- AN ANNOUNCER'SDAYContinued grammes are born !But all too soon, at : 9.40 Freddie goes along to compere and theblankswith gramophonerecords ? must keep to check up with the reception announce a variety programme, during Choosing the songs was one of the jobs he logs made out by the listening engineers. which the News is read on the Regional. did at home before he left in the morning, To freshen his memory he goes down to the Freddie's dinner jacket adds tone to the so within ten minutes the copies are brought Broadcasting House vestibule to see the party, and many of the women are in even- out of the vast B.B.C. library, and Miss huge time boards on which are marked ing dress.But most of the actors and Dixon has time to run them over on the rehearsal and programme times for every variety turns work in shirt sleeves, and piano half an hour before " zero hour." studio and every programme going on therearemore boiledshirtsinthe Office work goes on till : throughoutthebuilding-National, Re - studio audience than in the B.B.C. folk 4.45, when Freddie gets away to the facing the microphone ! B.B.C. canteen, where low prices and a help -yourself service prevail.There's time NOW FOR A SPOT OF LUNCH! The Old Regime for tea-and that'll be the last meal until Under old programme late to -night, for from the Children's Hour regime Freddie had more onwards it's almost a non-stop evening. At : time to himself between 6.30 and 8.0, when Changing into Uniform RegionalandNational 5.14 he's waiting in the Children's Hour were the same.But the studio. There's no mystery about the new LateNews means broadcast now." Barbara " is back after waiting till11.30 for the her wedding, and the whole show goes off last-minute news and the just as it did before the watching crowds at gramophonerecords. an exhibition, where the Children's Hour Freddie is not handling the was staged.Freddie waits (an announcer records to -night, but never- has to be a patient " waiter ") until he's theless midnight is boom- sung his two numbers, then creeps out of ing as he strides out into the studio so that he'll have time to change PortlandPlace,leaving into dinner jacket (B.B.C. uniform for the night Commissionaire announcers)beforethe 6 o'clock news. on duty in the vestibule There's no time for a bath to -day, though to handle 'phone calls and in this section of the building there is not Empire artists.And up- only a bathroom for announcers but a stairsin another studio complete bedroom suite like a miniature an Empire announcer is bachelor flat for announcers who have to saying :" Good -morning, work all night.News is read at : everybody" to a distant 6.0, when Freddie handles those triple- part of the earth. spaced, specially typed sheets, and silently On the way home grabs at last-minute news sheets which are Freddie runs through in his pushed through a window at him by the mind the names ofhis News Editor's assistants while he reads co -announcers -Li dell, the First News bulletin.S.O.S.'s, weather Marson, Esdaile, Phillips, bulletins, police news and allthe other " It's well past 1.15 before the rehearsal is over and everybody's nerves Maconochie,MacDermot stocked material of the News is typed on (except Freddie's) are a bit frayed and his own cousin Har- separate sheets. Weather bulletins are man Grisewood.Sleepily sent by messenger straight from Adastral gional and Empire." Mac "-Derek Mac- he tries to figure out who'll be in for the House, Kingsway. Then a few gramophone Culloch, the Children's Hour chief-has late News, who's on early duty, and so on records-and a break from programme duties been working late, and for half an hour the next day. till 9.40. This in reality means that until : there's an informal conferenceofpro- But he knows that the 'phone will be 9.10 Freddie can work in his office on gramme people, with Freddie, Mac, Michie ringing furiously at home if by any chance the daily reports which allannouncers and others discussing general ideas over he oversleeps and misses his cue ! A RADIO THRILL Ai ggl!fliM4:4MfitliwigrgigigAM'Afff one set isn't required for a period you The other day I was listening to the SOME RANDOM g merely switch off. Madrid station transmitting a piano recital. N I can't say you will mystify or impress A REFLECTIONS your friends ;it takes a lot to do that It was suddenly cut short. Excuse me, wc please," said the announcer in Spanish. A By VICTOR KING. it these days, doesn't it ?Sometimes I feel There was a hollow rumbling and then dead )11V-P.,',n-V-VPIOWn-Nn-V-V-PI-V-M-7,4 rather annoyed when folk take it for granted silence. that I have a television outfit and say quite " What d'you think, governor ? " he said. casually, " What about showing us some A few minutes later the recital was " I'm asking you," I replied. television." resumed as if nothing had happened. " And I'mtelling youit'llbringin They ought to murmur in an awed whis- My opinion of the Spanish lads rose tre- America.Seven and a tanner with valves." per : I suppose you haven't got television, mendously, for the next morning I read in I gave up the struggle and wandered on. have you ? my newspaper that the building had actually But I am bound to say practically every- been struck by a shell. TWO PROGRAMMES one is surprised if not amazed at the clear- Barcelona these days is to be found among If you fix up an ultra short-wave set for ness and brightness of the pictures. the forty -metre amateurs. It always opens listening to the television programmes you " I suppose we would expect yours to be and closes with the " International' in the might care to consider this natty idea. Join good," someone said t'other night. same way as does Moscow. the outputs of the two sets to the one out- Did I point out that any Tom, Dick, put transformer and feed your speakers or Harry could obtain equally effective OTHER DAYS from this. You can now fade -from the one results merely by buying an outfit through Wandering through a market -place in set and its programme to the other and their local dealer ? East London one afternoon I came across vice versa.It's rather impressive, without I did not. a stall loaded with radio junk. It included clicks or obvious switchings, to be able to a four -valve set which used tolistat go straight over from, say, a talk on the oosmormr ...ont,mmrAct thirty-five [pounds. Alas !thisancient National to the distinctive time chimes of kd -we regret tnat, pressure on our'space has made grandee was now labelled 7s. 6d.I asked the television programme at nine o'clock. it necessary to hold overPart 40of "Learning a the man at the stall if it was in working Of course, you do this merely by operating 4French Through YourRadio " untilnextweek. C,4 order. the volume controls of the two sets. When AMIS-M-MSVPrp-PAVIMISUMMArAg* Popular Wireless, December 5th, 1936. 365

.kYAMAigige41.1TZAMAMAMM,KAMITZW RADIOTORIAL STONISHING NEW QUESTIONS & 141 ANSWERS By K. D. ROGERS BROADCASTSNOWAVAILABLE n2Ory.VPSA INCREASING RANGE ToEvely W. B. C. (York).-I have a four -valve A.C. set with variable -mu S.G., S.G. detector, and a power output valve.I would like to convert LISTENER it into a superhet if possible, or could, I fit a double -diode pentode in place of the output valve ?The set is a commercial one, but I MEDIUM WAVE want to increase its range. I am afraid that you cannot do much to the set LONG WAVE In the way of increasing its range.You could add an external S.G. H.F. unit with its own power pack if you like, and the query department could give you SHORT WAVE useful hints on building one.But personally I should leave well alone and get another set when you can see your way to doing so.I am afraid you cannot TRAWLER very well turn the set into a superhet, and the idea of using the double -diode valve as you suggest Is quite impracticable. AIRCRAFT I regret having to be so disheartening, but the average commercial set is not easy to alter, and you would almost certainly upset the whole apple cart SHIPPING If you commenced to tamper with yours. OVERLOADING AGAIN POLICE K. G. H.(St.Albans).-I have been troubled with distortion when tuned to my AMATEUR local station on a battery set that does not distort when picking up more distant ones. I cannot understand what happens, for the sound I get out of the distant stations on the lipsON THE loudspeaker is just as loud as that I get on the local before distortion. takes place.Some- one told me that the detector, or one of the H.F. A LLAT YOUll?\"*Iplik valves, is overloading.Is that right ?I find I cannot tune in the local fully without dis- tortion, even if I cut down the L.F. volume control. You do not say whether the L.F. side of the set is going " all out 'in either case, but I assume that *GE.1\101 it is even when the local is being received. I am taking it for granted that what really happens Is that before you fully load the L.F. side of the set on the local station overloading of detector or H.F. valves takes place, but that you are able to turn the -e amaiii/iq A\-\--\141\\I L.F. volume control up on the distant stations, and you can make full use of the L.F. amplification, and that gives just as much volume as is possible with the local.Before I discuss what Is happening, I With continuous tuning from 12.2000 metres may say that an aerial volume control (I gave the connections for this last week) to cut down the input Why be content with a receiver which from the local to your set will enable you to tune in isonly designedtoreceive anin- the local fully without getting the distortiou, though finitesimal number of the multitude itwill not necessarily allow you to getall the of stations on the air ?Imagine the volume that you require.It certainly does seem interest you will find in listening not that eitherthe detector or the H.F. valves (or merely tobroadcasts,buttovital both) overload BEFORE you get enough input to communications betweenshipping, overload the L.F. side. trawlers, aircraft, police and the like, to far distant amateur This is easy to understand when one considers transmitters, and to the vast number of broadcast short- that the H.F. and detector valves have to deal with wave stations in all parts of the globe.These are the stations H.F. inputs, Which in the case of a nearby local which the Multiwave receiver can give you, programmes of (yours is only a few miles away) can reach a consider- 100 per cent, interest for 24 hours of every day.Why not able voltage. investigate this amazing and revolutionary design ? Itis Thus with an H.F. stage before the detector, not an expensive set-you can build it for less than Is.4d. theoretically you may get up to 220 or more volts a week.Its extremely simple construction can be under- of H.F. on the detectorIfyou do not volume taken by the veriest novice. Itis,in short, a set which control the H.F. Input.On a distant station the gives more stations than any yet produced, and yet at a voltage may be only a hundredth of that. price which defies comparison. It is very easy to overload the detector. You see, the L.F. part of the signal (which is the only part you are really interested in) may be only 50 per cent No. 4 " CONTACT," containing Four of the H.F. voltage, and it will hardly ever rise to more than 80 per cent.Thus the detector must be Star Circuits and Free V- Blueprint, able to carry more H.F. than L.F., and a 1 -volt L.F. input to the detector may mean a 2 -volt H.F. input. In most battery sets the detector will not stand NOW ON SALE.PRICE V-. much more than half a volt of H.F., sometimes less, without overloading.You must remember that it Graham-Farish Ltd., Dept. M.2. Bromley, Kent. has a low H.T. and so the grid curve is not very Dear Sirs,-Please send me : long.Thus you may be able to get but a small Contact Star circuits, describing fourbest circuits fraction of a volt of L.F. for the detector to deal with including the Multiwave and free blueprirtt, price Post and yet find the valve itself is overloaded. Free 1/.. Suppose you get half a volt of H.F. on the detector CI I am interested in Hire Purchase. -the most it will stand.Suppose that the average 0 I am not interested in Hire Purchase. level of modulation is 50 per cent.That means that you get.25 -voltof L.F. on thedetector.The amplification factor of the detector Is usually about Name 30 (sometimes more, sometimes less, according to the valve used), but not all that amplification Is put Address to full use.Only a fraction of it is actually " used," and in a resistance -coupled set with a 50,000 -ohms (Continued overleaf). 366 Popular Wireless, December 5th, 1936.

low magnification stage of L.F. to be properly loaded RADIOTORIAL QUESTIONS and to give the desired power output. of mixtures of television noises and sound As you do not tell me how many valves your set programmes when I tune my ordinary set to AND ANSWERS has, I cannot very well prescribe definite alterations. London Regional, and I should like a way You may be trying to get a single power valve after (Continued from previous page.) the detector to give you your full output without any - out of the problem.Can anything be fitted other L.F. amplification, but the fact that you are to my set to stop the interference ? satisfied with the results on the distant stations resistance you may get but a matter of 10 only as a leads me to believe that you have two L.F. valves, An article dealing with methods of overcoming stage gain for the detector valve. or that a pentode L.F. is being used. this trouble appeared on page 181 of " P.W." dated That means that the first L.F. valve gets about Try to work backwards through the set from the October 31st.The title of this article was " Curing 2.25 volts of L.F. to deal with.If you use a fair- output valve and see what voltage you require your Breakthrough," and in it you will find all you wish sized first L.F. valve it may not fully load the valve, detector to handle in order for the output valve to be to know. and thus you may be faced with the position of the fully loaded. detector being overloaded with H.F. before the out- If you do not know how to do this drop me a line &t,m%celcAtivxmozAglig.-vozAmszo put from it will overload either the first L.F. valve and tell me what valves you use, what type of or its succeeding valve. couplings are employed, and the ratio of any trans- I have mentioned some very broad figures, of former used.Then I can work back and let you Zri CHRISTMAS PARTY course.In practice it is not always possible in a know what L.F. input to the detector la necessary battery set to get a detector to take as much as to load the output valve-or the first L.F. valve, if National, December 25th. .5 -volt H.F. without overloading.Some people can that happens to overload first. Po; give only about 100 volts H.T. APPLIED, and then WZ 7..4'20,%M -741%-701t 5V-PON they have a 25,000 -ohms decoupling resistance and ,..-X-f%-fisiflf-'4%:U'Afl',:"K-'f,gfr4g1AVAgffregfAtfigAg-Iafir a 50,000 or more anode resistance in series with the CHARLES BREWER has,for thelast anode of `the valve and the H.T.That results in ih perhaps only about 40 volts actually " arriving " at The Editor cannot accept responsibility for manu- three years, been responsibleforthe scripts or photos. Every care will be taken to return informalPartyonChristmasDay. the plate, and so the working curve of the valve is MSS not accepted for publication.A stamped, lq$ very short indeed. Possibly the secret of success of this irre- In such a case it Is no good whacking up the H.F. addressed envelope must be sent with every article. input and expecting to get stronger output.You All Editorial communications should be addressed sponsible broadcast is that intimacy is the key- to the Editor, Popular Wireless,- Tanis House, note. must either keep the H.F. down and increase the Tanis Street, London, E.C.4. With famous artists it is possible to L.F. amplification or you must use a greater H.T. All inquiries concerning advertising rates,etc., stretch a point and capitalise the knowledge voltage on the detector. to be addressed to the Advertisement Offices, John that these artists have the power of what is You may, of course, be getting overloading of one of Carpenter House, John Carpenter Street, London, called in the profession " gagging." Actually, the II.F. valves, but usually (unless a diode detector E C.4. is being used) it is the detector that overloads first. The constructional articles which appear from " Christmas Party "ismost carefullyre- Try the effect of the aerial volume control or fit a timeto time inthis journal are the outcome of hearsed, and its success is due to its spon- multi -mu H.F. valve and control so that you can research and experimental work carried out with a taneity which, though sounding so unforced, tune in the local fully without distortion.Then view to improving the technique of wireless reception. try souse means of getting more H.T. " on to " the As much of the information given in the columns of is really the result of long years of training. detector.Increase the initial H.T. applied toit this paper concerns :the most recent developments if you can.Remember that because the det. tapping in the radio world, some of the arrangements and The Old Gang on a set or on a mains unit is marked DET. and is specialties described may be the subjects of Letters often of lower voltage than the other taps, there is Patent, and the amateur and the Trader would be It is hoped that " the old Christmas Gang " no need to keep to that voltage.You risk getting well advised to obtain permission of the patentees to will again be present. Tommy Handley, the ploppy reaction in some setsifyou increase the use the patents before doing so. ace of radio comedians ; Clapham and Dwyer, H.T. on the detector, but you will not upset anything else as a rule (notif the set has been properly and the Two Leslies will again gravitate to decoupled), and you will get a detector stage that inv-wmPiatm-77,1v3g,-nnvepoti St.George's Hall on Christmas afternoon. can handle a bigger H.F. input. TELEVISION INTERFERENCE Charles Brewer possesses a perpetual challenge In a mains set, where a big output valve .is used cup for musical chairs, presented by a listener and a large wattage output is required, the question D. T. S. (Muswell Hill).-As you can see ofdetector overloading sometimes reaches quite in Sheffield.This will again be competed for serious proportions.It is often necessary to use from my address, I am pretty near the Tele- totherunning commentaryoftheOld power grid detection In order to obtain good recti- vision station at Alexandra Palace.In fact fication and at the same time to have a valve that Christmas Party Gang. Last year it was won will stand a decent input-sufficient to allow fairly I am too close to it.I find that I get all sorts by Leslie Sarony. It Pays to Use Eddystone AIR TUNED I.F. TRANSFORMERS Compactunitwith ..geeyour copyof the high efficiency air ULTRA SHORT-WAVE H.F. CHOKES trimmerand genu- These chokes are single layer space wound on ine litz wound coils. DL. -9 formers, and have an exceedingly low 1937 EDDYSTONE Total tuning coverage self -capacity.21-10 metres. 400to500Kc/s. No. 1011. D.C. Resistance 1.3 ohms. Price 1/3 Gives high stage gain No. 1021. D.C. Resistance 0.4 ohms. Price 1/3 SHORT WAVE MANUAL with approximately 9 Kc/s. band - width. RADIO DEALER, No. 1014.450 Kc/s. From your Price 13/6 W.H,SMITH,or in difficulty POST FREE 1/ -

IMPROVED MICRODENSER MIDGET INSULATOR No. 900. Made from Frequentite for high For ultra H.F. and general S.W. use frequencywork,withN.P. POINTER KNOB AND DIAL CALIT insulation, low series resist- metal parts.I" overall height. finish No. 1019. Adirectcontrolcomprisingsatin ance, noiseless movement, extended Price 41(1. each aluminium dial engraved 0-100',with spindle for ganging. elegant shapedBakelitepointer knob.For 20 m.mfd., 3/9 ;40 m.mfd.,4/3 r spindlesonly. No.1027. Price1/3. 100 m.mfd., 5/- tosimplifystation BANDSPREAD TUNING OUTFITDevised. selection.

The Tank Con- Inparallelwith INTERCHANGEABLE COILS denser Unithas theTankcap- New low loss formers of DL -9 high -frequencyFLEXIBLE COUPLER a capacity range acity is the slow- insulation. Rigidly made and each coil matched.Free fromback -lash but of 10 x 14 m.mfd. motion Band - First-class remits assured. 4 -pin coils have twoveryflexible,thiscoupler achievedby a spread Trimmer windings, 6 -pin three windings. banishes alignment troubles. patented step by Condenser,with No. 959 6 -pin Set of 4 12-170 metres Price 16/.DL9. H.F insulation. For step device. a capacity slightly Complete with greater than each No. 932 4 -pin Price 14/.pindles. No. 1009. Price 1/6 Scale and Knob. step by step of the Tank Condenser.Complete with dial. TANK UNITCat. No. 1042.Price 6/ -TRIMMER UNIT: Cat. No. 1043. Price 6,6 E NCSHORT WAVE COMPONENTS STRATTON & CO., LTD., Bromsgrove Street, BIRMINGHAM. LONDON Service Depot : Webb's Radio Stores, 14, Soho St reel, Oxford Street, W. Popular Wireless, December 5th, 1936. 367

THE " TELE-SOUNDER" on the part of constructors are actually ?Mf,K=MACAIC=f;COZAMIZAM--24T-I'MeZ necessary to obtain excellententertain- (Continued from page 356.) ment from this unit. J. S. -T. A NEW CONSTRUCTO [Therewillbe more about the "Tele- MAGAZINE timesoccur ontheresistance -capacity sounder " in next week's " P. W."] Y1-31i170r02.53%-V-N-W-YV-M-7To ,1 coupled receiver. AS we go to press with this issue of The opportunities for experiments with " CABARET CARTOONS" " P.W." we havereceived from aerials are so great on 7 metres that I have "CABARET CARTOONS " is the title of a Messrs Graham Farish a copy of been tempted to include two spare ter- televisionshowonDecember7th, the latest edition of their popular magazine minals on the Tele-sounder. These terminals which will develop an ingenious idea of " Radio Contact and Television." are not actually connected to anything at Cecil Madden, the producer.The cartoonist Number Four of " Radio Contact and all in the Tele-sounder. But when you have will be Harry Rutherford, and his cartoons Television " appears from a cursory exami- will be presented in a novel fashion.Tele- builtand workedthisunit you may viewers will first see the names of the artists nation to be bigger and better than ever, desire to try different aerial arrangements. pencilled in bold characters ;then,as the and it contains among many other interest- You will see five methods of feeding the show proceeds, the camera will be faded over ing features full constructional details of tuned circuitinFig.4. In Fig. (a) a atintervalstoHarryRutherford'srapid four Star Receivers. A free shilling blue- sketches of each turn in succession.Artists di -pole aerial arrangement is employed. on the bill will be Janet Lind, in songs and tap print of one of these fine sets is also included. In this cane you do not use the Al and E dancing ;Levanda, foot juggler ;Leona and A comprehensive review of this latest terminals on the Tele-sounder.Instead de Leon, acrobatic dancers ;and Chaz Chase, Graham Farish constructor magazine will you connect the ends of a couple of turns of the American " silent comic." appear in the next issue of " P.W."D. S. " bell wire " to the terminals A2 and A3, these two turns being arranged around the main tuning coiL You can experiment with the number of turns and also the position of this extra coupling coil. To the terminal A2 you can connect a length of wire 5 ft. 6 in. long, while to the terminal A3 a similar length of wire may be attached. These wires may be arranged horizontally EXTRA or preferably vertically.Another arrange- ment is to connect the dipole aerial outside the house and join it to the terminals A2 and A3 by means of a feeder. More will be said CHRISTMAS about these matters later, or you may read 1937 Stentorian chassis, for about them in other articles.Fig.. 4 (b) better Christmas radio. Wider shows the connection of a simple aerial response-less colouration- greater realism.Matches ENJOYMENT to the terminal Al through an aerial coupler any set.Prices from 23/6 of .00005 mfd. (a pre-set mica condenser upwards. in the Tele-sounder itself).No earth con- nection is shown, and you may try dis- ASENSE of achievement-the thrill of connecting the earth connection on the TO MAINS enjoying (and giving your family) a main set. OR L7 BATTERY brand-new extra comfort or pleasure- what else could so positively ensure an Schemes To Try even happier " Happy Christmas " than

Fig. 4 (c) shows the normal connections TO MAINS OR usual ? to the Tele - sounder.You can take an BAllERY LEAD OR RI earth connection from the terminal E on 10 EXTENSION FOR a moment, picture the real pleasure the main set to the E terminal on the TO LOUDSPEAKER SPEAKERS which you-in your home-can obtain Tele-sounder. 4(d)instead of TERMINALS Of SET from the new W.B. developments. You can In Fig. " Long Arm" remote Con- using an earth connection you can dis- trol, for switching the set on have a new standard of radio reproduction, connect the earth' on the main set and oroff from any extension with wider frequency range and smaller point.One " Long Arm" " coloration " than ever possible before- attach a length of wire to the earth terminal serves any number of 1937 or you can enjoy a novel convenience from of the Tele-sounder.Fig. 4(e)shows Stentorian extension the " Long Arm " ; which (in conjunction another arrangement in which an aerial speakers. Price 15/6. with a 1937 Stentorian) enables you not which may be the normal or a separate wire only to listen in another room, but also to being connected to the terminal A2, while switch the set on or off without stirring from the terminal A3 is connected to earth.A the extension -point! turn or two of bell wire is passed round the main tuning coil and the ends of this bell THE process of fitting provides a keen wire joined to the terminals A2 and A3. interest. The results are certain-and Needlesstosay,theseexperiments remarkable. The cost is extremely small with a separate coil do not in any way call (and H.P. terms are available from your Volume control, type RIC- for alteration in the connections or con- for use in conjunction wills dealer if you wish). struction of the Tele-sounder.The coils of the " Long Arm" and 1937 Stentorianchassismodels. bell wire will usually be just a little larger Pr ice 5/6. MAKE up your mind that this shall be a in diameter than the main tuningcoil, memorable Christmas !Fit a new but you can arrange for the coil or the coils Stentorian, or a " Long Arm " extension of bell wire to be the same diameter, the point-or both. You will be glad you did ! turns actually passing between the turns of the main coil ;the bell -wire of course is covered with insulation, so that it does not matter much if the turns actually touch. A whole new field of experiment is thus 1937 opened up and as so little is known about the ultra -short waves, you will really be tl pioneering in a small way.Certainly your ei experiences will be of interest to all other 1937 Stentorian cabinet STENTORIAN model. Allmodels except users of the Tele-sounder.But I wish it the" Baby" (29/6)incor- PERMANENT MAGNET to be clearly understood that the standard porate volume control type RIC. Prices,29/6,39/6, arrangement I have adopted will of itself 49/6, 63/-. MOVING -COIL SPEAKERS give very good results, and no experiments WHITELEY ELECTRICAL RADIO Co., Ltd. (Information Dent.), Mansfield, Notts. ,--!

368 Popular Wireless, December 5th, 193G.

RADIO BARRAGE thinking all right.We know now where he's been to -night." (Continued from page 360). I TOM For lying at their feet were the two aged if you ain't out of my gardenin ten black hens that earlier in the day had seconds ! " he hissed between histeeth. pecked for a meagre living behind a yard THUMB " What the devil are you supposed to be and a half of rusty wire netting in Jerry BATTERY CHARGER ! doing -imitating a menagerie on fire ? " Franter's back garden. This remarkable midget battery " The idea was carols by radio," Mr. charger measures 3r x nff x 2i",Amblett enlightened him mournfully, " but incorporates a METAL RECTIFIER,every time I try to tune -in like this-" and will charge a 2 -volt accumulatorHis words were drowned by a fresh deluge at / amp. FOR LESS THAN id. PERof sound which whooped and bellowed and WEEK. Insist on- whistled, and paralysed the eardrums. The deep barking of old Rover, and the short sharp yaps of Scotty from the yard at HEAYBERD the rear, joined in the din, and a rudely awakened rooster flapped his wings and crowed cynically. It took Mr. Amblett some little while to Up-to-the-minute news concerning the subdue his unruly charge, and by the time -adio industry he had coaxed it into silence Mr. Gator had not only used up all the adjectives he could SPECIAL gauges for re -centring moving think of, but had shouted himself hoarse coilspeakersareavailablefrom in the bargain. Messrs. Holiday & Hemmerdinger of Exhausted, he leaned against the window Manchester. frame and pointed a finger at the garden These gauges, which are contained in a gate. Then he pointed his gun at Mr. Complete with Mains Lead small leather pocket case, are made in four and Adaptor. Amblett. thicknesses, each setconsisting of four SEND NOW FOR FULL The purveyor of carols by radio took the DETAILS OF THIS gauges of distinctive colour. The four thick- NEW LOW - TENSION hint. nesses are 015 in., 01 in., -0075 in., and BATTERY CHARGER. Sorrowfully shaking his head he turned -005 in. F. C. HEAYBERD & CO10, Finsbury St., dejectedly away, pushing the now silent To re -centre a speaker the centring screws .1 London,E.C.2. radio set before him. are loosened, the four gauges of appropriate ELECTRADIX BARGAINS Once well away from the farm, however, thickness inserted symmetrically in the gap, COIL TURN COUNTERS for check- his demeanour changed. He whistled a few the screws tightened up and the gauges ing the number of turns up to 9,999 on dial.Soiled, 1/3 each. bars of " Hark the Herald Angels Sing," withdrawn. BELL SETS. BestBritishTrembler, patted the big loudspeaker affectionately, The price of the set of gauges is 2s. 6d. stie.i 2/- each.Porcelain super -grade Pushes, sowbankrupt2/6linefor 8d. Flat Brass, and made his way briskly back to Jerry 1/6. Door Barrel,allbrass,2/6. Twin lead -covered bell wire, id. per yd.Indoor bell wire, single, 100 yds. Franter's cottage. 1/6; twin, 3/-. Transformers for ringing 100-v. A.C. DEMAND FOR G.E.C. TELEVISION 2/6. 220/40 A.C.3/9. He had barely rearranged the apparatus RECEIVERS SPEAKER. A RGAINS.- initsaccustomedposition,when Mr. Genuine bargainsinhigh-grade Althoughtheofficialtelevisionpro- moving -coilspeakers byfamous Franter arrived.He slipped in through makers. All new and offered at less grammes only started a few weeks ago it is than half price.Quality reproduc- the kitchen door, and Mr. Amblett noted interesting to note that already a consider- tionofspeech and music guaran- teed. with satisfaction the bulging sack on his able proportion of the 3,000 employees at MAINS ENERGISED back. SPEAKERS.- 6in. R. & A., the Coventry radio works of the G.E.C. are 2,500ohms,withspeechtrans. " It come off then ! "he exclaimed. former, 7/6; Hegra, 9in, with transformer, 1218; Bin. engaged in the development, production and with transformer, 15/, Magnavox, 6in. type, " 144," " But I knew it would.There was enough 2,500 ohms, 12/6; R.K., 8in. cone, 1,000 ohms, 10/6. sales of television receivers to meet the A.C. MAINS SPEAKERS, WITH RECTIFIERS. noise agoing on to cover the movements of present demand. 100/250 volts, llin. cone with transformer, 30/-.Jen- sen, 220-v.,7in. cone and transformer, 25/-;100-v., a cavalry regiment." Some idea of the work and material in- ditto, Iin. cone, 20/-; 100-v. A.C., 8in. cone with trans- Jerry deposited the sack on the floor former, 21/-. volved in the manufacture of a single tele- ALL -WAVE CRYSTAL SETS for plug-in coils,2 and wiped his forehead on a red -spotted tuning condensers, semi -perm. detector, 7/8. vision receiver will be gained from the fact HEADPHONES. -Sullivan 120 ohms, 2/9. Ericsson handkerchief. that the standard 23 -valve G.E.C. set con- and others,2,000 ohms, 4/6.Single highres.car - pieces, 2/6. " It did, and it didn't," he replied care- tains 3,980 parts. The alternative set incor- SMALL MOTORS.-D.C. 6-v,12/6;50-v.,14/.; " It was easy enough getting in, of 110-v.15/-;220-v., 16/, Home Cinema type, D.C. fully. porating an 8 -valve all -wave sound receiver or A.C., 18/6.A.C. 230-v. induction enclosed, 1/10 h.p. course, and it was a nice dark night.But A.C. electric drills, ditto to lin., with chuck and carries a further 2,000 pieces.All these flex,35/-. 39/8. Universal typo 1110t.,, 1/16 11.p., 35/.. them turkeys had gone.I groped around, COMMUTATORS. -For dynamos,motors,interrup. parts are made by the company itself mostly tors and multi -switches. Engine built,24 copper seg- but I reckon he must have sold 'em all, or ments, mire instil., finely finished, 2/-. Worth 7/6. from the raw materials. ROTARY CONVERTERS and ALTERNATORS, shifted 'em to some other place,'Nary a Some of the most highly qualified tech- as new, for 110-v. or 220-v. D.C., or drive 50 to300 one left." watts, ni silence cabinets.Also 6-v. to 150-v. sets cheap. nicians in the world are engaged in the HOME RECORDINGisgreatfun,andcheap. " Then what you got there ? " queried Record your voice with any gramo. on the MIVOICE research and development laboratories of AcousticRecorders.De Luxe modelinpresentation his friend, kicking the sack, carton, Two -guinea model, I8/8. Speakeasie guinea pet, the G.E.C. The researchers at Wembley 10/6. Junior ditto5/6. Spare blank records, 4/. dos. Jerry grinned. have their own high -definition transmitters, MICROPHONES. -We aremakers andcarrythe largest and most.varied stock in London.Prices are low " Well, not being able to find no turkeys, enabling them to experiment at all times of and these are models Tablefor all purposes. Model " W.W.II." For I thought that a couple of nice fowls would the day. home broadcasting.Bakelite square be the next best thing.After all, we went bodyonbronzebase,containing At the Coventry factory, which is at transformer, switch and plugs, is a to a lot of trouble to get 'ern !So I just present outside the Alexandra Palace radius, marvellousproductionatalow price.Worth 2 guineas.Only 15/, grabbed a couple of birds which were in the the development and testing staff have pro- LesdixNo. 10BPedestal,10in, house where the turkeys should have been, high,12/6.Lesdix Superior No. . duced their own test equipment, remarkable 12BB Ring,14in.pedestal, 18/6. wrung their necks, and-" He waved Hand mikesin2-in-calfe.No. 11 apparatus which even gives visual repro- at 5/8.Superior typo,No.11a, significantly at the sack. 7/8. Home microphone No. 11 is a ductions of the characteristics and efficiency sologeneral-purposerobustmike Bob Amblett scratched his head. of the many components, both before and w'th solid bakelite body, back ter- m nals, front metal grille, hand or " Better than nothing, I suppose," he ad- after final assembly of the receiver. si ng design, 5/6. mitted." Let's 'ave a look at 'em ! " He COILS.--Short-wave coils, plug-in type,1/8each;Ribbedlow -loss toppled the contents of the sack on to the formers, 13d. ; Long -wave 2 -pin coils, 1/-; Reaction tuners, 9d.; Mains red -tiled floor. interference,H.F.twinchokes, For a long moment they regarded the two RADIO 2/-; Solenoids for model or relay operation, 6-v. or 12-v., with fin. loz. iron travel, 2/6. SPARK COILS.-lin., fin. and lin. gap, with conden- dead birds, and then Jerry Franter turned ENGINEERING sers.Larger coils,2in.to7in. flaming spark,short to Mr. Amblett with a dazed look in his Home Study Course wave spark transmitters' for boat model control. 17/, THE BEST MEANS TO A 1,000 gifts in our latest Bargain List " ." free eye. SECURED RADIO CAREER " I told you once afore, Bob, that I don't WRITE for interesting FREE 12.page booklet and start ELECTRADIX RADIOS TODAY on the road that MUST lead to SUCCESS. 218,Upper Thames Street, London, E.C.4. likepolicemen who think ! "hesaid TheInstituteof Practical Engineering, Phone: Central 4611 savagely. " And old Hobiday has been First Avenue House, London, W.C. Popular Wireless, December 55th,1936. 369

sM'S-RZ.VVVV,Sk-nnn7P.72;Mtrn-Pri LSI unstable.. It is worth while to take a good resistance as being added to the value in deal of care to determine by trial the exact the decoupling resistance. ,A0 TECHNICAL JOTTINGS best value for the detector anode voltage Items of Interest toAll and to check up now and again that the Electrolytic Condenser Points. ;'t detector anode is actually receiving this I came across a set the other day in By Dr. J. H. T. Roberts, F.Inst.P. voltage, neither more nor less. which an electrolytic condenser was fitted and this was connected the wrong way The Question of Input. round ;the owner of the set was of the Detector Adjustments. I have indicated what happens if the opinion that electrolytic condensers were I was talking recently in these Notes detector anode voltage is too high, but on not all they were cracked up to be and you about the adjustment of the detector stage the other hand, if it is too low, the output can easily see why.There seem to be and what an important effect this had volume will be reduced and furthermore quite a lot of people who do not realise upon the performance of the set as a whole. the detector stage will be unable to handle that an electrolyticcondenserisquite One point I forgot to mention was the signals of normal strength without dis- different in its modus operandi from an question of the voltage applied to the anode tortion.As you increase the voltage, the ordinary mica or paper condenser, or a of the detector.If there is a resistance in stage is able to deal with a larger input, variable air condenser.In the case of the anode circuit of the detector valve, as provided, as already mentioned, you do not ordinary condensers thereis,of course, is frequently the case, it is generally best go beyond the useful limit. no polarity and it doesn't matter which to apply the maximum voltage which you In the case of a circuit using a resistance - way round they are connected.With an can getfrom thehigh-tensionsource, fed transformer you must regard the anode (Continued on next page.) whatever it may be, in order to make up for the drop in voltage in the resistance. Itis obvious that, -when any current is passing, the voltage applied actually to the anode of the detector will be less than the voltage applied to the remote end of the resistance,thedifferencedepending,of course,in accordance with Ohm's Law, upon the value of the resistance and the amount of current which is passing. OVER50TYPES ZrZ-11M-AiMMACtilLI&M=1,-'107griPsic.lia, FUN AND GAMES AT THE Every Battery and Mains Set can be B.B.C. vastly improved provided you replace By VictorKing. all" fired "valves with their modern 'Twas Christmas Day in the " Big House,"74 The broadcasters were full of good cheer. Hivac equivalents. Holly around the microphones 65 And barrels and barrels of beer. Why put up with distortion,lackof Amid laughter, frolic and shouting Announcerscrackedawfully' naice " volume and sensitivity, when for a small jokes, And even the talks director sum you can modernise your receiver. Referred to the others as " blokes." 0-Then in came the "Big House" Master And all became silent and still. They wondered how he would greet them, This personage so grim and chill. However, he smiled quite kindly, So they all took a long, long breath, VA And shouted together like thunder, "HAS ANYONE HERE SEEN' GEF'?" ej., AK ,ggfimAcogira gam rz THEscuErinnur oc Voltage Drop. To take a case in point, let us assume that the anode resistance is 25,000 ohms, VALVE with a current of 2 milliamps, then the difference of voltage or potential at the ends of the resistance will be 50 volts. 01=dommasmosi/' If you want 70 volts on the anode of the BRITISH =Z" MADE detector, and a current of 2 milliamps pass- ing, it means that you will need 70 plus 50, that is 120 volts applied to the other THE SIGN OF A GOOD VALVE end of the resistance. As regards the actual voltage to be Have you had particulars of these special types ? applied to the anode of the detector, this naturally varies with different types of valves, some taking rather less than the HIVAC SHORT-WAVE VALVES value I mentioned. - HIVAC HARRIES VALVES Critical Detector Voltages. HIVAC MIDGET VALVES The voltage for the detector used not to be very important-I mean the exact value of it-but .some circuits nowadays are quite SCOTT-TAGGART USES critical in regard to the detector voltage. and a very small change in voltage will make a big difference to the operation of HIVAC FOR HIS S.T.800 theset.As everybody knows,if you increase the anode voltage you generally Details ofallHivac types sent free for postcard request increase the sensitivity of the set, but this is not a good way of. increasing the sen- HICH VACUUM VALVE CO. LTD., 111-117, FARRINCDON ROAD, LONDON, E.G. 1 sitivity and furthermore a limitis very - soon nut to it, because the set soon becomes 370 Popular Wireless, December 5th, 1936.

TECHNICAL JOTTINGS place will damage the condenser.Make certain, therefore, when using one of these (Continued from previous page.) condensers that it is connected the right way. electrolytic condenser, however, this is not 1936 the case.This kind of condenser isin Tuning Scales has seen a good deal of thought reality a type of battery or cell.You know What great improvements have been andcare expendedovercircuits. Nine how in an ordinary primary battery, such as made in the tuning scale and, in fact, the times out of ten the set -designer has speci- a wet Leclanche, or one of the units of a dial or face of receivers generally during the past two or three years.It was not so fied aJ.B.Condenser or Dial. More and so-called " dry " battery, one of the greatest more constructors are discovering that for difficulties which had to be overcome was long ago that the front of the receiver was the " polarisation " of the cell. a confused litter of odd valves, rheostats, superlativeperformance andreliability a knobs and switches.It wasn't very long J.B.Component cannot be bettered. The Polarisation Effect before it dawned on somebody that the Our Service has always been at the dis- proper place for the valves was inside the Whencurrentpassesandchemical set and not outside, and soon after that a posal of constructors and we shall be pleased action takes place in the cell, some of the general cleaning -up of the front of the to assist you with any of your set problems, products of the chemical reaction form receiver took place and as many components small or large, during themselves on one of the plates and tend to prevent further current from passing. as possible were put away where they were In the case of all types of battery this polarising effect has had to be got rid of. of4-.1KALIMIBeregl&%01W'SZWACIliCle.4 1937 This accountsfortherelativelylarge TEN LITTLE ANNOUNCERS amount of manganese dioxide mixture which surrounds the carbon rod in the By Victor King Ten little announcers centre of an ordinary " dry " Leclanche All in a line, cell. One dropped two aitches, In the electrolytic condehser, however, Then there were nine. this polarising effect is actually made use of Nine little announcers. 05 One couldn't wait, and not only is no attempt made to do He switched off a symphony, away with it, but everything is arranged ayye Then there were eight. CF so that the polarisingeffectwilltake Eight little announcers, place as instantaneously and as completely Dressed fit for heaven, CONDENSERS as possible.The result of all this is that But one used a made-up tie ; when current tries to pass through the cell Then there were seven. (I am calling it a cell for the moment) in Seven little announcers AND DIALS Went to the " flicks," one direction, it instantly causes polarisa- One obeyed Mae West's request ; JACKSON BROTHERS(London)Ltd., tion, and shuts itself off, whilst when it tries Then there were six. 72, St. Thomas St., S.E.1. Telephone:Hop 1837 to pass through the opposite direction it is Six little announcers, able to do so.This latter is obviously the Very much alive, direction in which thecell is not to be One dropped a betting slip, Then there were five. connected. tlF Five little announcers On the ground floor, °ENGINEERING Large Capacities Obtainable One said " Lift ?Ihateuplift !" When connected in the way in which the Then there were four. OPPORTUNITIES' current cannot pass through it, it builds up Four little announcers this polarising layer on one of the electrodes Down by the sea, FREE! One got caught by a very lone wave, Thisunique Hand -book and, as the layer isin extremely close Then there were three. shows the easy way to secure proximity to the electrode, the electrostatic A.M.I.C.E.,A.M.I.Hech.E., Three little announcers A.M.I.E.E., A.M.I.A.E., capacity between the two is very large, due A.M.I.W.T., A.M.I.R.E. Started to chew, andsimilar qualifications. solely to this very small distance between One parked some gum on " mike," WE GUARANTEE- them, a distance which is almost infinitely Then there were two. 0. "NO PASS-NO FEE." smaller than anything we can achieve in Details are given of over Two little announcers, 150Diploma Courses inall building up mechanically a condenser of Bubbling with fun, branches of Civil, Mech., Put some really swift stuff over, Elec., Motor,Aero., the ordinary type.This accounts for the Radio and Television And, of course, they both got the sack. Engineering, B uil ding, Government extraordinarily large electrostatic capacities Employment,etc.Write forthisenlightening Hand -book to -day FREE and post free. which can be okktained within quite a small British institute of Engineering Technology, 101, Shakespeare House, 17. 18. 19, Strat- compass with electrolytic condensers. ford Place, W.1. out of sight and where also they were much Chemical Action more likely to do their job efficiently. Then However, to return to the question of came the craze for the minimum number of inaacsvocvacxxxvooms polarity, you will see from the foregoing controls, even down to the mythical " one - Please be sure to mention why it is so essential that the electrolytic knob -control " set.After a bit the swing " POPULAR WIRELESS " condenser should be connected the proper was the other way, as it was found practi- when communicating with way round.If it is connected the wrong cally impossible to reduce the set to one - Advertisers. way round, not only will it not act as a knob control if you wanted to get any com- THANKS! prehensive performance out of it.. IIKWOOMNICSIWOOMNICVOCNSNS condenser, but it will allow D.C. current to pass and the chemical action which takes (Continued on next page.)

THE TRULY UNIVERSAL THE VALVE OF THE FUTURE! AT LAST RADIO SET IS HERE! SIX POINTS ON The set which can be Used Anywhere and

under any conditions-safe against mains breakdowns. COSTARGAN The Hyvoltstar Universal All -Waves, UNIVERSAL HIGHVOLTAGE VALVES sT800 A.C. D.C. &Combined Battery Receiver. SNOW AVAILABLE TO CONSTRUCTORS WORLD-WIDE SUPREMACY! REVOLUTIONARY IN EVERY WAY: 4.NO BARRETTERS, and No Breaking The only set of its kind in the world. Can be used on 1. LONGER LIFE. Down Resistances required. any mains, on its own batteries, in your own home, 2. GREATER SENSITIVITY. 5. NO MAINS TRANSFORMERS NEEDED, or friends, car, boat, or on safari, and be sure of peak CHEAPER CONSUMPTION. GUARANTEE. results. PORTABLE-TRANSPORTABLE. Send3. to -day for a FREE BLUEPRINT6. 6 MONTHS' and full particulars of any Hyvoltstar offers the fullest range of 4, 5, 6, OSTAR-GANZ HITS FOR RECEIVERS, RADIOGRAMS AND TRANS- 7, 8, 9, 10 -valve Universal All -wave Supers, MITTERS. AMPLIFIERS OR SHORT-WAVE ADAPTORS you are and Radiograms, which enable you to tune interestedin. The New Prices, amazing value and results will in to any part of the world from any part surprise you. of the world, at full loudspeaker strength. WE OFFER 20% P.R. ALLOWANCE ON*ANY OID KIT. UNIVERSAL HIGH VOLTAGE RADIO, LTD., EUGEN J. FORBAT (Dept. A), 28-29, Southampton St.,Strand, Fy 28-29, Southampton St.,Strand, London, W.C.2. Telephone TEMWe Bar 8608, 4985. TEMple Bar4985, 8608 Popular Wireless, December 5th, 1936. 371

TECHNICAL JOTTINGS (Continued from previous page.) Cleaning Up the Controls. LISTEN IN PEACE! Arising out of all this, over a period of a few years, there is no doubt that the present- day receiver has been very thoroughly " cleaned up " as regards the appearance THE and layout of the dial and controls.In my WITH AERIAL opinion itis not desirable that all the S.T.800 controls should be put inside the set,I MIAMIFORYOUR mean allexcept the on -offswitch and To missIDEAL tuning, even if it were practicable, because ESSENTIAL FOR I think you get so much better operation if you have control, on the front of the re- PERFECT ceiver, of the principal factors, in addition RECEPTION to those just mentioned, for example the READY ON ANY volume control, reaction, tuning, selectivity ALL WAVE SET and so on.I suppose there are plenty of TO ERECT people who would like a set which just NOTHING switches on as simply and as easily as the TO ASSEMBLE electric light, but it would seem to be quite impossible to avoid some kind of tuning on Abolish man-made static, with this amazing newAll -British- AerialOutfit.90%ofthe the front of the set, otherwise how are you trouble experienced -inall -wave receptionis NOISE, which the B.T.S. Anti -Noise going to select different stations ? Then, Cuts Out Noise and Increases Aerialefficiently suppresses, vastly improving your -.Vadio reception on again, I think everybody wants to vary the Efficiency on Every Waveband ALL wavebands. In addition to an aerial transformer, the outfit includes a special set loudness of the setatdifferenttimes. transformer, fitted with switch for reception on ALL WAVEBANDS: This EXTRA com- Again you must have the on -off switch ponent will improve the sensitivity and selec- somewhere handy and, as well as all this, r --SPEC!FIED for tivity of your receiver. - Suitable for all sets, A.C.,Battery and D.C., you will want various stations where the BANDS. Complete Outfit,and ALL ready WAVE- 25i. reaction control has to be adjusted and Mr. John Scott-Taggart's for instant erection ... where selectivity becomes important. I FROM YOUR ITELE-SOUNDER RADIO DEALER Press the Button." So you see right away you depart from B.T.S.Tuning Condenser, Type STC.425 - 3di the simple press -the -button business and I B.T.S. Short Wave Choke, Type UHF.2 - I 0 don't see how you are ever going to get Obtainable from allGood Dealers. over it.Furthermore, the interest of the set would be much less if there were nothing BRITISH TELEVISION SUPPLIES, LTD., Faraday Hse., Charing X Rd., London, W.C. more to do than just switch it on and off. It seems to me that we have by now pretty well reached the happy mean between the clutter of controls, some of which need not be at the front of the set, and the opposite extremeofso-calledone -knobcontrol. Visual tuning indicators incidentally have greatly helped in accurate tuning and this "TELE-SOUNDER" type of indicator seems to meet a long felt want. Television Sound Unit Short -Wave Adjustments. Designer's Specified Components When using a short-wave receiver of the single -stage -tuned - H.F. - detector - reaction Belling -Lee type it is a great help if you are able to "R" Type Terminals, 1003 s. d. adjust the response of the receiver when loud signals are being received without A 1, A2, A 3,E. 4 at 3d. - - 1 0 having to adjust the reaction control.In order to achieve this desirable end what " R " Type "Midget" Wander Plugs, 1019 you want is a suitable volumecontrol, Terminal H.T. +,G.B. - 2 at2d. - - 4 preferably in the aerial circuit, at any rate 1003. Each, 3d. (See also No. 1295, below) somewhere in the high -frequency region. 1 4 When the reaction is eased off, the set is rather apt to lose selectivity, unless you have some kind of control of the type re- FOR A GOOD JOB WELL DONE ferred to above, and you will probably find Get the complete catalogues. or yourself getting two more stations A FREE Folder Catalogue " Radio Spares and Connections." crowding in on top of one another. Also,46 -pp"Radio and Electrical Accessories," 150 illustrations, including 75 blue prints of curves, diagrams, circuits, and con- structional details and specification of every part.Price, 8d. H.F. Control. post free A very simple arrangement is to use a " Midget " potentiometer for the purpose of the high - BELLING &LEE LTD1 STRIKE OUT ITEM Wander :nmPRIDCF DIV.O. M.00% NOT REQUIRED. frequency control as mentioned above, the end terminals of the resistance element Plug,1019. " Midget" type I Please send, free, " Radio Connections" folder. Each, 2d. with bakelite being connected to the primary of the aerial handle and I enclose 8d.for new book," Radio &Electrical plug-in coil, whilst the tap or slideris hexagon top, Accessories." joined to the aerial, and one end of the 1295. Each 2d.I primary to earth.The actual resistance Name value of the element of the potentiometer is not very important, but a value of about POST THIS COUPON IAddress 1,000 to 2,000 ohms is usually suitable. Pop. W. 5.12.36 (Continued overleaf.) 372 Popular Wireless, December 5th, 1936.

TECHNICAL JOTTINGS ---"44MISCELLANEOUSRECEIVERS, COMPONENTS AND (Continued from previous page.) ACCESSORIES ADVERTISEMENTS Surplus, Clearance, Second -Hand, &c. 3d. per Word (Continued) Isolating Condensers in Mains Sets 3/-earls-American valves,allpopular types. 90 - In using a mains -operated set or mains - 6d. per word for first words in heavy type day guarantee.Full range in stock, National Union, 6,- per line for displayed lines Hytron,Triad, Metal, Glass and M.G. Send for lists. operated amplifier, whether this is connected (12 pt. type) 3/-each-Mullard, Cossor, Mazda, Marconi, Osram directly to the mains or derives its current valvesforD.C.receivers ;allperfect. 90 -day from a mains unit, it is a good plan to put a Minimum Charge I - guarantee.State type. Send Cash, or C.O.D. fixed condenser into each of the leads to the Remittance must accompany order. RADIOGRAPHIC, LTD., 66,;OsborneSt., Glasgow, C.1 The purpose of thiS obviously CONVERSION UNITSfor operating D.C. Receivers loudspeaker. Advertisements for these columns are from A.G. Mains, improved type,120watts output at is to isolate the speaker from the rest of the accepted up to first post WEDNESDAY 52 : 10 : 0. Send forourcomprehensivelistof outfit.You might think that one con- M OR NI NG for the following week's issue. Speakers, Resistances and other components. The Proprietors have the right to refuse or WARD,46,FarringdonStreet,London,E.C.4. denser would be sufficient, acting after the withdraw advertisements at their discretion. Tele. :HOLborn 9703. manner of a single -pole switch. But for the Postal orders in payment for advertise. A THOUSAND BARGAINS same reasons that it Is desirable to use a ments should be made payable to the MAINS TRANSFORMERS, M.C. SPEAKERS, MAINS double -pole switch for completely isolating Amalgamated Press, Ltd., and crossed. VALVES, SHORT-WAVE GEAR, CABINETS, Etc. All communications should be addressed one part of a circuit from another, it is to Advertisement Department, "Popular desirable also to use a condenser in each Wireless," John Carpenter House, John PREMIER SUPPLY STORES Carpenter Street, London, E.C.4. 20-22,HIGH STREET, CLAPHAM, S.W.4. lead instead of a condenser in one lead SEND 3d. STAMP FOR CATALOGUE. _only.With a single -pole switch you break the electric circuit, but you do not com- RADIO BARGAINS. Amazing Prices.New and RECEIVERS, COMPONENTS AND Shop -SoiledSets, Components.American Valves, pletely isolate the component, whatever it 5/6. Europa A.C.Valves, 4/6. Mullard M.B.3A may be-for example, an electric iron-from ACCESSORIES Battery Sets, E4/10/-.A.C. Superhets, £5.All -Wave Surplus, Clearance, Second -Hand, &c. Sets, £9.Midget Portables,A.C./13.C.,65/-. All the mains, because the other pole remains New Goods.State Type of Set Required.Midlands connected, and it is possible to get an electric SOUTHERN RADIO'SWireless Bargains;all goods Cheapest Factor. Ferguson, Pilot, Air King,, Belmont guaranteed and sent post paid. All -Wave Sets.Stamp forList. shock from the iron to earth or to some LITTLER,2, Barras Lane,COVENTRY.'Phone: 5933. other connection. A double -pole switch, G.E.C.3 -valveBatterySets," Battery Compact Three," with 3 Osram valves, moving, -coil speaker BANKRUPT BARGAINS.List free.Allnew goods. of course, completely isolates it and there is in beautiful bakelite cabinet, brand new, in sealed Batteryall -wave 3-v.,16-2,000 metres, complete no possibility of anything of the sort.In cartons, fully guaranteed ;50/- each (list55/10). withH. F.pentode, detector and pentode valves, SPEAKERS.-CelestionSoundex permanent magnet, and M.G. speaker,in handsome walnut cabinets, 10/- ; Telsenpermanentmagnet,with10 -ratio 79/6. Ormond 3-v.A.C./D.C.withM.C.,59/6. If44..'.-TX0Z1Iii-Ag-Oigg %f,iCU.ITZr.ialir,Agr.,94K1 transformer to suit any receiver, 12/6 ;Telsen loud- Mullard 6-v. A.C./D.C. superhets, 7 gns.Ferguson, speaker units, 2/6 ;allbrand new and in sealed Pilot, etc.,all -wavers, and large stock components, IR cartons. valves,etc. Get my priceforanything radio. COILS.-Telsen,iron core, W349, Midget size, 4/-; Butlin, 6, Stanford Avenue, Brighton. OUR CONTRIBUTORS 41 Type W478 (twin), 9/- pair ;W477 (triple), 16/. set ; Type W476 (triple superhet selector and oscillator) S.T. EIGHT HUNDRED.Guaranteed specifiedKit, A- Popular Wire'ess and Television Times "lil 16/-set,all ganged coils complete on base with 53/7/6. ExtractorKit,51/1/- Specified Valves, eihas an unrivalled team of regular contributors. 0 switch ;TelsenI. F. transformer coils, W482, 5/- ; £l/6/6. S.T.700/SOo Conversion Kit, 33/6, as specified. Here are just a few of them : Telsen dual rangeaerialcoils,withaerialseries S.T.800 Coils, 21/-.Cash, C.O.D.Lists Free.Parko JOHN SCOTT-TAGGART -The most4 condenser incorporated,W76, 4/. ;Telsen aerial Radio, 24, Terminus Road, Brighton.Open Sundays successful set -designer and technical journalist 4 series condensers with shorting switch, 2/- ;Telsen 10 till 3. L. F. ofalltime.His S.T.setsconsistently break transformers, Type R.G.4(4 to 1),3/- ;all S.T.800.Author's kits, E3/7/6, A.G. versions, E8. Radio tnew records-the S.T.800,recentlydescribed brand new, in sealed cartons. goods. Lowest prices. Part exch2nges. Servwell Wire- IKin " P.W.,- has achieved a colossal success. MICROPHONES.-Ace(P.O.) microphones, complete less Supplies, 64, Prestbury Road, London, E.7. r!: Dr. J. H. T. ROBERTS-Hisweekly notes 4 with transformer, ready for use with any receiver, have an immense following. 4/6 each ;Ace concert microphone, complete on HEADPHONES. Brown, G.E.C.,B.T.H.,Nesper, kt chromium stand with volume control, ready for use Sterling, Marconiphone, etc.From 2/6 pair.Postage .kik W. L. S.-Themost popular short-wave expert with any receiver and amplifier, 11/-. PS and writer. 6d. List free. RESISTANCES.-Tru-ohm1 -watt, colour coded and CRYSTAL SETS.Complete.Guaranteed. Borne - 03 VICTORKING-Through his weekly 0 marked, 36 assorted capacities on card ;6/- per card. Jones, 5/6.Ditto, double circuit, 8/-.LargeP.O. Reflections ''hascreated avast 4 R Random AMERICAN VALVES.-A fullrange of valves for all type,10/-. Crystal detector, complete parts,1/-. itcircle ofreader -friends. it American receivers ;6/- each. Sensitive permanent detector,1/6. PostRadio, ARIEL-Theleading radio news commentator. HEADPHONES.-Lightweightheadphones,double 183, Caledonian Road, London, N.I. k''m L MARSLAND GANDER-Pioneertele-1 pole type, 4,000 ohms, each ear piece ;3/-pair. vision programme critic. REPAIRS.-Anytype ofreceivers. American, MISCELLANEOUS S.C. GILLARD, M.A.-Whocontributes 4 British, etc., repaired by expert staff. our special language series. WEHavePurchasedtheComplete Component MILNESH.T. Unit for sale, super 120 -volt capacity, if Stock of a Well-known Radio Dealer and Manu- as new, cheap. Seen by appointment only. Compton, A K. D. ROGERS-Authoritativelyandin- !,14 facturer, and we are offering the complete stock in 44, Marmora Road, London, S.E.22. oterestingly answers readers' queries and regularly n parcel lots as under :- iii engages in general topics. I; WE BUYfor cash, all types of Modern Second-hand 5/- Parcel, containing components to the value of at RadioSets,Accessories,etc. UnbeatablePart - A Popular Wireless and Television Times least20/-,comprisingchokes,resistances,coils, exchange allowances for new goods.Bring, send, or switches, condensers, wire and circuits, 5/- per parcel. write.University'RadioLtd.,82, Hampstead Road, A-on sale every Wednesday. Price 3d., and if 10/-Parcel, containing components to value of at isathispresent special Christmas issue happens to be X. least 45/-, comprising variable condensers, screened Euston, London, N4W.1.'Phone :Euston 3810. thenfuturenum,ycuamongztensoft.,ands first number you h a vese wen hopewe may.., chokes, switches, resistances, screened coils,wire, SELLING UP.S.T.600 £3, specified valves ; S.T.15 a circuits, etc., etc.; 10/. per parcel. of our regular readers. ditto, 50/- ;S.T. 300 Star, £1 ; Telsen 28 m.a. elimi- ALLArticles Included its These Parcels are Brand nator charger, 30/- ;Atlas ditto Et ;" Block " L.T. 1 New and Modern. SO m.a.7/-. Components; no junk.Write: 14, V.-aff:CAMX.filMafa'Aglggeeig-AAMAMIMFgi SOUTHERN RADIO.-Branchesat 271-275,High Dovedale Road, Sheffield, 7. Rd.,WillesdenGreen,N.W.to ; 46,LisleSt., London, W.C.2.All mail orders to 323, Euston Rd., SITUATIONS VACANT the same way with the condensers, if there London, N.W.1. SOUTHERN RADIO, 323, EustonRd.,London, POST OFFICE ENGINEERING.Excellent openings is one in each lead the loudspeaker is en- N.W.1 (near Warren Street Tube).'Phone Euston for youths and men under 40.Start £3/13/0 weekly tirely isolated from the set, so far as direct 3775 - at age 17 and no experience required.Full details on connection is concerned, but is still able to AMERICANSignallingKeys,8/6.CodePractice application to N.I.E. (Dept. 606), Staple Inn Bldgs., operatein a normal way through the Keys-Buzzy-Click &Flash,4/6. Headphones, High Holborn, W.C.1. 2/6pair.Milliammeters, 0-25,0-50, 0-100,6/9 medium of the condensers. each.ElectrolyticCondensers,bigvariety, 2/ - WIRELESS AND TELEVISION. Marconi'sand If you use high-tension batteriesfor each.Multi -contact, wave -change switches, 2/- & other Employers require hundreds of trained men 2/6. 156-1 Slow-motionDials, American, 1/3. next year.We train students forallbranches of operating the amplifier or radio set, it will Test Prods, Heavy Flex -5,000 -volt test, 2/6 pair. radio at our Residential Colleges inSouthampton then be sufficient to use a condenser in American Valve Holders, 4d., 6d.,7d., 7d., 4, 5, 6, andColwynBay, andguaranteeappointments. only one lead, corresponding to a single - 7 -pin. OctalSockets,8 -pin,10d.Cand Ohms Licensed by Postmaster General-recommended by (.3 amp., 250 ohms), 2/-.Short-wave H. F. Chokes, Marconi's. New term commences January 6th. pole switch. But where connections to the 9d.Set of 4 Short-wave coils, 4 & 5 -pin, 5/-.Dry Write for freeProspectus.-The WirelessCollege, mains are involved, I strongly advise you to Electrolytic 12+12+12+12+6+6, 475v.wkg., Colwyn Bay, or to London office, 4, Winton Av.,N.11. 3/6. DryElectrolyticMetalCase,18+8 mfd., use a connection in each lead, just as I 475v.wkg.,3/..DryElectrolyticMetal Case, always advise people to use a double -pole 4+4+4 mfd.,475 V.wkg.,3/.. BeansPower Allapplications for Advertising Space switchwhereverpossibleinstead Tubes, 6L6, /9. Popular types American valves, of a 3/- each.1,000 other items in stock at crazy prices. in "POPULAR WIRELESS" should be single -pole switch. All satisfaction or money refunded guarantee. addressed to the Advertisement Depart- For the fixed condensers to be inserted RADIOGRAPHIC, LTD.,66, Osborne St., Glasgow,C.1. ment, John Carpenter House,John CarpenterStreet, London, E. C. 4. in the leads to the loudspeaker a value of PLEASE BE SUREto mention " Popular Wireless "

2 microfarads each or more is desirable. when communicating with Advertisers.Thanks! December 5th, 193A POPULAR WIRELESS iii

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Who could resist such good fare as you will lied in RADIO PIE It's a least of tasty things; interest and humour, facts and laughter !Every listener will find a vealth of fascinating facts. intinsbigphotogravure bookofmicrophone personalities. Hundreds of intimate,lavishly illustrated life stories, articles by favourite radio artists, interesting tit-bits-they're all here RADIO PIE is a guide to our stars-of-theair and an entertaining' magazine rolled into one. Hurry, and buy your copy today. -

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PrintedInEngland and published every Wednesday by the Proprietors, [HE AMALGAMATEDPtiNss, Um.. I'heFleet way House, Farringdon Street, London, 1:k. t. AvertisententOffices :JohnCarpenterDouse, John Carpenter Street, London,L.C.I.ltegisteroifor transmission by Canadian- Magazine Post.SubAr riphor tee :InlandandCanada. 17/4 per :tritium. Abdond (c\oept Canada), 1911 per annum.Sole A cuts.; for Australia and Netx Zealand :Messrs. I iODTOD A: (401.H L .: and for South Africa:Central News A ;, licA.Lt d. Saturday. December 5th. 1930. POPULAR WIRELESS, December 12th, 1936 REGISTERED AT THE 0.11.0. AS A NEWSPAPER. CHEAPER TELEVISION By J. C. JEVONS

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Popular Wireless, December 12th,1936. 373

EDITOR :G. V. Dowding Asst. Editors :A. Johnson Randall, A. S. Clark

STATION NOTES HONOLULU HUM A NEW ONE RADIO NOTES & NEWS RECORDING ANGEL ? HE LOOKED IN

Emerald Isle to Wait Awhile Singapore hopes to get its medium wave tial election ; but when that party received ALL the talk of a short-wave station for station going by Christmas or the New Year. a mere 650,000 votes the public murmured the Irish Free State appears to have (Even if " Mad dogs of Englishmen go out "Oh Yeah ? " been so much boloney. in the midday sun " to fix it !) Sadly, Father Coughlin withdrew from The new Minister for Posts and Tele- his radio pedestal.Smilingly, FranklinD. graphs is sympathetic, but the first cost of a Roosevelt switched on his set at the White station would be in the neighbourhood of Warsaw No. 2is a stationhoping to House, and noticed that hole in the air. £50,000, and then there's the maintenance. quadruple its power by Christmas.This Like Little Audrey, he laffed, and he laffed, After the station had been erected it would will bringit to 8 kw. ;the new Lwow and he laffed ! cost another £15,000 a year to " Keep the transmitter on 50 kw. (377.4 metres)is little divil dancin'," so the project is post- proving a regular (L)wow ! Here's a New One poned for the present. WHEN the P.O. sleuth sud- denly pokes an inter- Dictionarical BEAUTY LISTENS -IN rogative nose round the Eccentriccability door and demands to see the ITis a long time since we wireless licence of the negligent had a smile together over householder, that worthy often the gallant attempts of the manages to find-instead of the foreigner to master the English licence-a more or less novel language.(I say " gallant " excuse. advisedly, for some of these Few delinquents, however, fellows do far better in our can put up such a good one language than we should in as' the Newcastle Emlyn, theirs.) Carmarthenshire, gentleman Thefollowingletterwas whose case came before the receivednotlongagoby Whitland magistrate. Ferranti's : In a letter to the court the " Sir, I take the freedom to defendant said that he had ask you if you willbeso only recently returned to this kindtosend me aquite country from Canada, where completedocumentationof he had livedforthepast your alimentation trans- seventeen years.In Canada, formers suitable to strong and he said, once you have got the quite powerful receptors and set and the licence you need alsomicrophonical aimplifi- not bother to renew the licence catorsreaching20warbled every year.He did not know watts with their price. Thanks that there was a different law befor, My veryrespectful in this country ;but he had salutations-" This' charming young lady is obviously enjoying the programme from the Cossor to pay 10s. for his enlighten- " Microphonical plifi- all -wave set.Itis a four -channel six -valve superhet, and costs fifteen guineas. ment. catorsrs " is good ; but to anyone who listens ambitiously " warbledwatts " A Hole in the Air Is Your Uncle an Eskimo ? is perfect. WHENa favourite radio star ceases to IF your auntie ran away and married an broadcastinthe U.S.A. they Eskimo you will be interested to know Station Information picturesquely refer to his absence as that the Canadian Broadcasting Corpora- WILNO, Poland,on559.7metres, a hole in the air. tion in the kindness of their heart3 will try should be using his new 50-kilo- The famous American broadcaster, Father to convey to her your Christmas greetings watter instead of the old 16 -kw. set Coughlin, " Radio Priest," who was sup- or other message, free of all charge.The by the time these words appear in print. posed to be able to sway the votes of worthy Corporation,knowingthatthe * * millions of electors, has fallen right into Eskimos, Mounties, trappersandother furry such a hole, and it looks impossible for him denizens of the Frozen North tune in nightly Prague,on470.2metres,hasbeen to get out. to their radio programmes, have arranged whispering on a 5 -kw. set during alterations The good Father had announced that his a " Northern Messenger " service at stated to plant, but expects to be in full voice radio audience would poll at least 9,000,000 times, to which exiles are invited to listen. again after only a short period. votes for the Union Party at the Presiden- (Continued overleaf.)

FOR ORDINARY AND NEXT WEEK: THE A.C. A.P. THREE TELEVISION PROGRAMMES. 371 Popular Wireless, December 12th, 1936.

A LIBRARY WHICH CONTAINS 60,000 RECORDS

Relatives and friends are invited to send the fields is being experimented with on a Recording Angel ? short messages, with particulars of address big scale. The rumour that powerful scent - KINDLY remove your glovesfor a and so forth, to the Canadian Broadcasting sprays are to be fitted on machines for muck- moment and join with me in a Corporation, Ottawa.All being well the spreadin' is so far without confirmation. genteel clap of the hand for Mr. message will then go out on the next Adams of the B.B.C. " Northern Messenger " programme. Won't This'll Make You Whistle "Never heard auntie be pleased ? THE Radio,Physical and Television tell of him," ses you. Society must have had a great time " Shame . on 'e," Hum in Honolulu at the recent lecture by Dr. C. G. ses I. T ONE of the Honolulu stations has been Lemon,forthatarchticklerofthe Mr. Adams is the 111111' having trouble from hum.Not the audience'spalate producedcathode-ray custodianofthe nice, polite, electrical, 50 -cycle type apparatus, oscillographs and what not that B.B.C.'sgram o- of hum either. But the good old-fashioned, danced living patterns before the members. p h on erecord '1111 per- Pure sine waves from frequency records nose -assailing, library-and it is a 111Eri111101101111W1 fume - demanding, were demonstrated, and then the boys record library, for it skunk -like, .,nasal were invited to whistle into the mike and has about60,000 HUM, or stinko ! see the waveform which resulted. records on the racks.All kinds-song, Engineers, hold- Various vowels were sung, and " a good dance, symphony, chamber, operatic, vocal, ing their noses home,foreign,funny,near -funny and tightly, investi- plain miserable. gated indespera- Mr. Adams has to time every record's tion, and what do HENRY HALL'S CHRISTMAS playing to the split second, file it where it you thinkthey can be grabbed in a hurry, and index it for found ? No,sir, PROGRAMMES all programmes in which it may be wanted. not dead cats, but The period around Christmas is always exception- He calculates that if he gave an A to Z ally busy for Henry Hall and the B.B.C. Dance dead lizards, which had been crawling into Orchestra.Arrangementsforthisyearare as recital of all his records he would take about the transmitting coils, attracted by the follow : twenty weeks.But he likes the work. They will be on the air on Tuesday, December warmth or something, and then had fallen 22nd, and Wednesday, December 23rd, from 7.20 to Never gets into a groove ! victims to high voltage. 8.0, and 5.15 to 6.0 respectively.On Christmas Day itself from 12.30 to 1.15 there will be a session of More Power for the Vatican Asked how big they were, one technician seasonably cheerful music, while from 9.20 to 11.0 on said that the biggest was only about two the same evening Henry Hall's Christmas Tree IThas recently been disclosed that the inches." But," he was careful to add, will be decorated with Turner Layton. Oliver Wake- success of the Vatican broadcasting field. and Haver and Lee. " you know how it is with lizards, one inch This special programme will take place in Studio 4 service has encouraged the authorities smells like one whale ! " at Maida Vale, and it is intended to set up in the studio there to plan another and more powerful an actual Christmas Tree decked with the hundreds of cards, calendars and otherseasonable greetings transmitter.Instead of using a mere ten Sidelights on Siege which every year listeners send to the Dance Orches- kilowatts, as at present, the new equip- tra. The decorations on the metaphorical Christmas ment will use fifty kilowatts, and will cater FOR those who want to know the day-to- Tree are, of course, all well -tried and not -found - day truth about Madrid the possession wanting broadcasters.Turner Layton who, with his for the audiences in distant lands such as of a short-wave set has proved es- single vaudeville act, My Piano and 1,- has found Australia and Japan in the east and South favour with audiences, and listenersall over the sential.You will have noticed how the country, last broadcast .on September 5th.Oliver America and Pacific settlements in the west. B.B.C. announcements have referred again Wakefield, whose running commentaries on dance The Pope himself is greatly interested in tunes haveset up ahighstandardinpresenta- the Vatican radio service, and when com- and again to last-minute news received by tion,isexpected to intersperse a special Yuletide wireless, and many readers have told me flavour into his witty remarks. pleted his new installation will be one of On Boxing Day the Orchestra gives a late afternoon the most efficiently equipped short -wavers how they have been fascinated by side- programme from 5.15 to 6.0, and a review of the lights of the siege. dance hits of 1936 from 8.30 to 9.20.Christmas Eve in the world. One curious instance was quoted by the and Monday of the same week will be devoted to necessarily intensive rehearsals.On December 30th He JustLooked In Spectator."It was a broadcast to the the Orchestra will play from 5.15 to 6.0, and on New effect that " Comrade Blank has lost his Year's Eve from 10.25 to 11.30 listeners will be in- of my cheery correspondents in wallet containing 45 pesetas.Will anyone vited to ' Roll up the Carpet and Dance." ONEMalaya wants to know if I have heard finding it return it (to such and such an this one ? address), as this amount represents the During an evening broadcast from a whole of this brave comrade's capital." time was had by all."Any " PM:" station on the out- Apart from this, said the writer, the reader hankering after this kind of uplift skirtsofKuala whole thing was a little like listening in to and joy should write to the Acting Hon. Lumpurthe doors a murder. Sec., Mr. W. R. Walker, 48, Fitzjames and windows of the Avenue, London, W.14. building stood open Culture and Agriculture on account of the AFEW years ago the farm-hand was a Two More Centurions for Europe heat.The solitary corduroy -wearing thaw -bacon, whose WHEN the 100 -kilowatt stationfirst announcer,about conversationwas almostunintel- sailed into our ken I was so pleased to read the news, ligible-" 'E knaws what she be arter, 'e with the three figures that I styled wasappalledto dew," and the like. such stations " centurions." There have noticethatthe Nowadays, how- been many of them in the past few years, Malayattendant, ever, rubber-tyred and now I see that we are to have two more. contrary to all rules, was going to butt in farmtractorsare One of them is under contemplation in and say something.Sternly pointing to tr7- being equipped with Tunis, the first cost to be borne by the the SILENCE notice, the announcer glared wirelesssets,and French Government and the upkeep by the at the would-be interrupter, and calmly "The Farmer's Tunisians.The other 100-kilowatter is for carried on with his duties. Boy "hasgiven Sweden, in the vicinity of Horby, where At the first break in the programme, way to " Yippy-I- there is at present a ten-kilowatter. however, he seized the opportunity of a Oh-Ky-Ay " - and By the way, smarties who itch to point switched -off mike to reprimand the dusky other snappy urban out that Tunis is in Africa, not Europe, can helper and ask him what he meant. melodies. save their sarcastic comments, because by " Sir," explained the dusky, " I only An Agricultural Engineering official of universal consent the European telegraphic, wanted to tell you that a big tiger looked Washington has declared a policy of taking telephonic and radio sphere has been ex- at your head through that window behind the drudgery and dullness out of farming, tended to bring in the North African com- you.For the moment, sir, I thought he and in the U.S.A. radio entertainment in munications. was coming in ! " ARIEL Popular Wireless, December 12th, 1936. 375 OPERATING THE "TELE-SOUNDER"

HOW YOU CAN TUNE -IN TO THE TELEVISION SOUND PROGRAMMES AND THUS OBTAIN A NEW SOURCE OF ENTERTAINMENT

BY JOHN SCOTT-TAGGART

HEN 1 am asked to write on you can make the Tele-sounder oscillate valve should oscillate with the reaction " how tooperatetheTele- you stand a slim chance of picking up the knob about half -way round.You choose sounder " I can only reply that television radiations, because the merits ofa suitable H.T. socket to give you this there is nothing to write about. reactionareessentialforsatisfactorily effect. Of course, the wander plugs of Having connected the H.T.+ loud reception. the main set are not altered. lead to its appropriate socket Reaction is varied on the Tele-sounder, and the bias lead to the grid -bias battery, not by the usual variable condenser but H.T. Adjustment and Oscillation you have little to do.Pull out the first by a variable resistance which alters the If you plug in the Tele-sounder'sH.T.-{- L.F. (i.e. next to the last) valve of the set, anode voltage of the Tele-sounder valve. at too low a voltage, even with the variable put the adaptor-valveholder in the empty Increasing the H.T. voltage will increase resistance at zero the valve will not oscillate. valveholder and replace the valve in the the reaction and if you increase the H.T. Even if it oscillates with the reaction knob sockets of the adaptor-valveholder; then on the anode enough the Tele-sounder at one end, this is not very satisfactory. take out the detector valve of the set and valve will oscillate. On the other hand, you might put so much insert it in the valveholder of the H.T. on the H.T.+ plug that Tele-sounder. Take the aerial off the valve would not stop oscilla- the set and connect it to terminal ting even with the reaction knob Al on the Tele-sounder.The atzero(i.e.maximum anode earth of the Tele-sounder may be resistance). connected to the earth, but this All this is just a theoretical is not usually necessary. explanation. All you need to You are now ready to tune -in *low and do, is to plug-in the tothetelevisionsoundpro- H.T.-F plug of the Tele-sounder grammes.It will be an exciting in a suitable socket of the H.T. moment. For thefirsttime battery (or mains unit) so 'that probably you will be down on a with the reaction knob half -way wavelength of extreme shortness. roundthe" set goesinto No longer do you picture great oscillation.(Remember that the reflectinglayersinthesky " set " is now a 3 -valve arrange- perhaps sixty miles up which ment consisting of the detector assist in long distance reception. valve in the Tele-sounder and the Now the lofty aerial of Alexandra last two valves of your main Palace situated on high ground receiver.) will be shining its waves like a You can always tell when the searchlight into your house. setisoscillating by the faint " breathing " noise.If you turn Easily Picked -up the reaction knob quickly the Thisisan oddlyexciting suddenstartingofoscillation thought.You do not even need will cause a click.However, I to hang out an aerial to "catch" need hardly describe what every the waves. They will come right radio constructor has experienced, into the room unless you are and clearly no one will be working particularly badly shielded.The the Tele-sounder unless he has waves can almost be " handled." some experience of working an The aerials to pick them up can ordinary set. be diminutive.Certainly a di- poleaerialwhichisspecially Mr. Scott -Taggart with the " Tele-Sounder."Simple construction and The Tuning Note suitable is a very simple affair- operation are two outstandirg features of this wonderful unit. Having made the " set " oscil- twoverticallengthsofwire late you simply search until you 5 ft. 6 in. long each.But never mind the It is advisable to remember that more hear the noise of the television " vision " aerial just now.Your usual one will do. H.T. and therefore more reaction can be radiation (an erratic sort of hum) or ,the In fact, you are sure to get some results obtained in two ways.You can either actual sound programme a little " higher even without an aerial-so even the worst reduce the anode resistance by means of up " the tuning condenser.The firstis is likely to be quite good. the reaction knob or you can reduce the not very exciting and you will ignore it. That detector valve, i.e. the Tele-sounder's Tele-sounder H.T. tapping on the H.T. The " sound " programme is what we are own valve, is the only one I have doubts battery itself.Obviously you would not after. about.If you useaMazda L2 you get smooth reaction by altering the H.T., You can tune -in on the tuning note which will be quite all right.This is the detector say,12 volts at a time !The variable is given for about five 'minutes before the valve of theS.T.800 set,,soS.T.800 resistance is therefore only to provide a advertised time of starting(at present owners will in no case require to buy a smooth control of the H.T. on the anode 3 p.m. and 9 p.m.).There is no harm in new valve.But here again I advise you of the Tele-sounder valve. oscillating to find the station but remember to try your own detector valve.Several As valves and H.T. battery voltages vary, that you should not use this method once types will no doubt work but others will you may need to alter the socket into which the programme has started.It is very not oscillate down to 7 metres, and unless the H.T.-F of the Tele-sounder goes.The (Continued overleaf.) 370 Popular Wireless, December12th, 1936.

(Continued from previous page.) do this usually without ill - effect. You can, in fact, work inconsiderate to so do as you will produce from a circuit.On 7 metres a whistle in perhaps thousands of homes.' you cannot safely work from As a matter of fact, once you know where a circuit.I have provided to find the sound programme you can make a " practical -theoretical " cir- a mark on the panel and you will find it cuit for the Tele-sounder so quite unnecessary to make the set oscillate that you can see the actual to find the Alexandra Palace. terminal connections. If To tune -in accurately you will find it these are altered, even though useful to control reaction with the left the theoretical circuit remains apparentlythesame,' you * * may get odd coupling effects which may cause instability, An alternative THE COMPONENTS USED badreactionorthreshold version of the " Tele-sounder."In IN THE "TELE-SOUNDER" howl. Even an inch of wire thiscasethe panel TUNING CONDENSER : .000025-nsfd., at these very high frequencies forms, as it were, the B.T.S., type S.T.C.425. lid of a simple box. AERIAL COUPLER : .00005-mfd.,J.B., can alter the whole operation. No bottom is needed. base -board trimmer. If then you want to play FIXEDCONDENSERS: ducks and drakes with my design to im- constructors who build thisunit.You 1 .00005-mfd., Lissen Mica. 1 .0001-mfd., Dubilier type 620. prove on it, to use different gauge wire, to should say what your aerial is like arid 1 .0003-mfd., Dubilier -type 620. avoid that soldering joint on the main the position of it, e.g. in the room, on the 1 0.5-mfd., T.C.C. tubular type 250. VALVE HOLDER : 4- in, Eddystone No. 949 coil, or otherwise ruin the unit I ask you roof, etc. By telling other readers you will L.F.TRANSFORMER VarleyNiclet, toabandonallideasofbuildingit. be adding to the sum total of knowledge standard 1 : 3.5. You'll only blame me or the manufac- on waves about which little is yet known. RESISTORS : 1 1.megohm, Dubilier turers if you do not get good results. You 1 30,000 -ohm. Dubilier 1 -watt. will prove a very poor advertisement for * * POTENTIOMETER : 50,000 ohms, Erie, less switch, but with terminals. the design and we would all prefer you NEXT WEEK we shall publish SPECIAL COIL (specify this unit) : Colvern. did not attempt it. a FULL-SIZE SHORT-WAVE CHOKE B.T.S. type But if you keep to the design you are U.H.F.2. 2 KNOBS: Baer:, type K.20. assured of success.By the way, do not WIRING PRINT of the VALVEHOLDER ADAPTOR : With isolated place the unit on a metal tray or very TELE-SOU NDER." Elide ase tappedfilamentterminals, close to metal objects.I once knew a man TERMILIPSe: A:.1, A.2, A.3, E., Belling -Lee who worked a set on a zinc scrubbing All those intending to build this board ; the effect on the coils was disastrous, remarkable unit should make a WANDER PLUGS H.T.-E, G.B.-. Belling- Lee Midget type No. 1019. and naturally on 7 metres the effect is still point of securing a copy of this SCREEN :Aluminium sheet,24 S.W.G., worse. Also,don'tpointthe speaker valuable aid to construction. 7 X 5 in., Peto Scott. TERMINAL STRIP :4 X 13 in., Peto Scott. directly at the Tele-sounder valve or .you In Next Week's " POPULAR 1 PANEL: Peto-Scott. may get a microphonous " ring." 2 SIDE PIECES :Peto-Scott. But do not imagine that these very WIRELESS and TELEVISION 4 feet 18 S.W.G. tinned copper wire and TIMES," onSaleWednesday, 1 m.m. insulating sleeving. short waves are terribly tricky to tune. The Tele-sounder is very much easier to December 16th 40.9r work than any short-wave set. The reason hand whilp gently tuning with the right is partly because we are only concerned * hand.I say " gently " but actually there with the reception of one wavelength. The service area for Alexandra Palace is is no need for great care.The tuning This vastly simplifies matters.Naturally declared to be 25 miles, so if you live condenserisverysmall and no slow- itis easier to work than any ordinary beyond that distance you may set up records. motion knobisneeded. You tuneit broadcast receiver because there are only Probably all the usual laws will be found to very much as you tuned the ordinary two knobs-tuning and reaction. be broken by these waves. detector and L.F. type of set.Nothing I should very much like to hear from all Needless to say, the Tele-sounder is so could possibly be sim- simple that I cannot pler.The reaction is- FOLLOWTHE DESIGNCAREFULLY conceive of anything in fact,it must be- going wrong. There better than on an ordi- should be a 100 per nary set, so that you cent. ofsuccesses. will delight in its smooth- But do 'keep to the ness and freedom from design,tightenall change of tuning. yourterminals,and The only point which make sure the valve is callsforcommentis one that will oscillate theoneImention, down to these short namely trying different wavelengths. H.T. tappingsfor You will get a great the Tele-sounder's own deal of fun out of this H.T.+ plug. verysuccessfulunit and you will get real Note These Points B.B.C. entertainment A few warnings may of thevery highest notbeoutof place. grade - entertainment Do not, as you value that you can only get yourmoney,altera if you own a television single wire or position. set of the £100 class. On 7 metres you can You willbe" years get queer effects.Do ahead " of your neigh- not alter the way the boursevenifthey wires run or think that haveall -wave sets. this wire can go to this While if you are also terminal just as well as Owner of an S.T.800 to that one since both you will certainly be are joined together.It The constructor can make his own coil and H.F. choke inclover with every- if he prefers.Details of bow to do this are given on thing the ether has to cannot. Onlow-fre. the next page.An importantpointtoremember quency circuits you can when building the unit is to follow the design with the utmost care. offer. J. S -T. Popular Wireless, December 12th, 1936, 377 How to make THE COIL AND CHOKE FOR THE "TELE-SOUNDER" By John Scott -Taggart

THE ultra -short waves are likely to revive is soldered to the coil at the end of the " That's a job for you," said one of the interest in coil -making.There are so fourth turn (see diagram), family. few turns it is very simple to " roll Thiscompletesthecoilitself.The " I'm hanged-" I began.After all, your own." dimensions of the ebonite stripare given in you can't expect a man who has spent For the main coil of the Tele-sounder you the diagram.The holes in require to start with about 30 inches of the strip are s in. in diameter. NOTHING DIFFICULT HERE 16 S.W.G. bare tinned copper wire.You The method of mounting the also require to make an ebonite strip 2 in. coil on the strip is shown on by in. by 3/16in. The additional a separate diagram. " material " consists of threein. 6 B.A. round head brass screws, three 6 B.A. brass The H.F. Choke nuts, and three 6 B.A. terminal heads. Now let us consider how These last may be taken from old com- the H.F. choke may be made ponents, otherwise ordinary nuts may be if itisnot bought ready- used. made. The materials required are :2 in. of hardwood dowel Winding the Coil rod 7/16 in. diameter; about The " former " for shaping the coil is the 3 ft. 28 S.W.G. enamelled 0.5 mfd. T.C.C. tubular condenser-which, copper wire ;a few inches of ifthe manufacturers do not mind my 18 S.W.G. tinned copper wire. sayingso,is why this component was Drill a 1/16 in. hole at each chosen !The finished coil will then have a end of the rod.These holes The B.F. chokeis quite simple in construction, as you will see from mean diameter of one inch. are 3/16 in. from their respec- this diagram. Using this " former," wind on nine com- tive ends.Bare one end of plete turnstightlywith adjacent turns the 28 S.W.G. enamelled wire for about the previous ten hours struggling with the touching.Do not leave any gaps between 1 in.Pass it through the hole in one end innards of sets to devote his evening to turns.Although the completed coil has of the rod so that the bared inch length the same pastime, can you ? projectsont he I went on with my tea, ignoring the set, 444,1" other side.Take a which was as dead as a doornail. A feeling sa03.0. piece of 18 S.W.G. of deep gloom had taken possession of me.

Bartr,ale rept.fts cr.e.zste tinned copper wire I remembered that a rich uncle had pro- Tceresece Cbrty-,e4 4{<4.e about 5 in. long and mised to come over and hear the " posh " pass one end outfit, and it was quite on the cards that through the same to -night would be the night-due to the hole in the rod so general cussedness of things. that itprojects "tDo hurry up and get it fixed," sister Ethel was saying, as I buttered a round of -I. Eaorzea about 2 in.Bend rir cretifc.4c,4 this projection toast. /Fen" /6,-t...- ISOASSIIVE 0111 round the rod. Now Young William volunteered to setit '-rY8-if&<4.., Lr1444.49 right, but his optimism was suppressed by 6.6',4 solder the bared 28 /14 ".--"Haufevss his mother.I felt half inclined to let him ' S.W.G. wire and the tS4== try his hand ;in fact, I was wishing all Here are all the details you need for making tinned copper wire broken-down sets at the bottom of the sea. the Tele-sounder tuning coil. (c7.7.-4 Of Olesetecreng together as shown I finished my tea and lit a cigarette. The in the sketch. room was miraculously empty,andI only eight turns, when the coil is released Now wind 21 turns of the 28 S.W.G. sauntered across to the set.As I did so from the former the turns spring out to a enamelled wire on the rod, spacing it evenly there came a jangling sound, which gradually slightly larger diameter.The excess over between the two holes in the ends of the increased in volume and then righted itself the eight turns is used for making the rod.The spacing is actually about 5/64 in. into a cinema organ in full cry.Jolly stuff connecting loops at the ends of the coil. The end of the winding is finished off in the it was, too.I sat down. Having wound on the nine turns, release same manner as the other end. The sound attracted the other members the coil from the " former " and stretch out of the household. the windings like a concertina until the * * " Hallo !Got it fixed already ? " said turns are 3/16 in. apart, i.e. from the centre sister Ethel. of one wire to the centre of the next one to EVERYTHING WAS I expanded considerably. Everything was it.This requires a certain amount of bright again.With two eggs inside me I coaxing with the fingers to get correct and BRIGHT AGAIN could afford to be genial. even spacing but it is quite easy to do.' By W. NIMMONS. " It's easy when you know how," I said ; while William looked on enviously. Centre Tap Connection The music stopped. In blissful ignorance The ends of the coil are bent down at I HAD just returned home after an exhaust- of what was coming, I beamed on them all. right angles and parallel to each other (see ing day on my rounds as a set repairer. " We regret the break in the transmission diagram), so that there are exactly eight Sets had been unusually stubborn, and between-" the voice from the loud- turns between the bends.The length of my temper, always somewhat short, was speaker began. wire projecting beyond the bends is in. as brittle as a latchkey after sonny has These projections are looped (by means " hardened "it by subjectingit to the* tilt of round -nosedpliers)as shown in the baptism of fire and water. A handsome celluloid dial for the S.T. 800, diagram. similar to the card dial issued in Popular The home set-a quality affair designed Wireless but revised up to a later date A piece of what is left of the 16 S.W.G. for local station listening only-was work- ofprinting,isobtainable for2s. 6d. wire is Used for the centre tap connection. ing smoothly as I hung up my hat and coat post free, from Celluloid Printers, Ltd., This wire is 1 in. long and is looped at one in the hall.I had just washed my hands, Kingston By-pass Road, Surbiton, Surrey. end in the same way as the ends of the coil. and was sitting down to a good tea when the This is the only dial approved and checked The other end is bent over at right angles set gave a splutter and a fizzle and then by the designer of the S.T.800. f in. from the end.This bent -over portion went silent. 378 Popular Wireless, December 12th, 1936.

the dotted -line curve Al, Ill, Cl, Dl.This naturally helps to cut out that part of the signal B which might otherwise interfere TUNING DEVELOPMENTS with the clear reception of signal A.The The radio set has improved enormously during the past year or same applies to any other part of the tuning. two, particularly in regard to improvements in tuning, Automatic scalein which worth -while stations are grouped closely together. Volume Control is probably the most valuable technical develop- This sharper tuning effect is obtained by ment in this field and some of its most important features are superimposing on the normal muting bias, described below an extra voltage which is derived from the incoming signal through a highly -tuned By CARDEN SHEILS circuit with a " peaked " resonance curve. At a certain point on the peak, such as X, the circuits of the set are suddenly restored ALTHOUGH the design of receivers time the circuits are automatically restored to normal, and the action of the muting tends to get a little more complicated to normal, and the new programme comes circuit is removed.This produces the sort and " cunning " each year, the latest through at full strength. of band-pass effect shown in the drawing. models are, if anything, even easier and The use of " quiet " A.V.C. also lends more satisfactoryto handle than their itself to certain other refinements in tuning Visual Indicators Unnecessary predecessors. This is, no doubt, what we control. As already mentioned, its chief Another interesting point is that itis all expect, but it does not by any means purpose is to distinguish between the worth- possible to tune a receiver fitted with this follow as a matter of course. whilesignal and the various kinds ofkind of " quiet " A.V.C. by ear alone, As a general rule the more complicated " noise " and low -strength signals that are instead of having to depend upon visual the " innards " of a set become, the more not really worth listening to.This is just indicators. As is well known, the use of difficult it is to keep the controls simple and another way of saying that the muting A.V.C. tends to broaden the audible response foolproof, and it is only by the exercise of circuit is set at a certain " threshold " point, of the set more or less, as shown by the flat- considerable ingenuity that designers have below which all noise, heterodyne, and mush topped curves A, B, C and D, so that it managed to maintain the present standard. is cut out, and above which the received is impossible to tell by ear whether one is To some extent it is, of course, due to the tuned accurately to the provision of larger and more cleverly - centre of the carrier - arranged tuning -dials, as well as to the use IMPROVING THESELECTIVITY wave or to one side or of distinctive illumination for the different other of it.A visual wavebands, both of which fall under the indicator is then usual- heading of purely external improvements. ly provided to show, In addition, there are various kinds of either by the length of ." visual " indicators to assist the accurate the discharge column, tuning of sets fitted with automatic volume or by the deflection of control. These are linked up to the internal a spot of light, when circuits because they are operated through thecircuits are dead A.V.C. voltage developed in the set. " on tune." M Silence Between Wanted Stations But by gingering -up But when we come to the problem of theactionofthe " quiet " tuning, we begin to get into muting circuit, as Ordinary A.V.C. makes already explained, the deeper waters. audibleresponse is the valves most sensitive when there is .5.44A"runiAg ioax, 4 VC narrowed down to such nothingusefulforthem topickup. " Quiet " A.V.C. is then brought in, as a an extent that a station If an A.V.C. circuit isarranged so that the datum line, M, -is made to can be tuned in accur- sort of hand -maiden, to suppress all the vary with the strengthof each signal, the selectivity of the circuit is ately by ear alone. Any noisy rubbish which-in the absence of a improved. slight movement of the worth -while programme-would get through control to one side or into the loudspeaker. In other words, it signal is allowed to pass freely through to other of the centre -line of the carrier now automaticallykeeps the loudspeaker the loudspeaker. causes a rapid falling -off in signal strength, " mute " until it has something worth while In the figure, the shaded portion at the just as though the set were not, in fact, to say. bottom represents the general background provided with automatic volume control. Now consider what happens when the of " noise'which is usually present all owner of a set has been listening, say, to over the tuning -dial.The straight line M Fecamp, down at one end of the tuning - indicates the datum line of the " quiet " * * scale, and then decides to change over to A.V.C. bias which forms the threshold TEA -TIME VARIETY Athlone, away up at the other end of the between good signals and noise.A, B, C, D An Interesting Regional Programme scale.Obviously he will pass through quite represent anumberof" worth -while " on December 11th. a number of intervening stations, each signals, some being stronger than others, sufficientlypowerfulto" release "the but all rising above the datum line M. muting or suppressor circuit. Each of them It is rare indeed that listeners are able to Tuning Varied to Suit Circumstances hear a variety programme during a mid -week willaccordinglyproduce an unwanted afternoon, the evenings having been found, " blurb " of sound in the loudspeaker. Now if instead of keeping the muting as a general rule, the most suitable time for " Not a very troublesome effect," one voltage at the same constant dead level of such a broadcast.On Friday, F. H. Piffard might say, but the modern designer thinks the line M, M, it is made to vary with the willbring tothe microphone well-known otherwise. He aims to get absolutely quiet strength of each signal, as shown by the artists from many corners oftheBritish tuning between any two desired stations, dotted line at Al, BI, Cl, Dl, certain Empire.Magda Neeld, for example,is an no matter how widely they are separated advantages follow. Australian soprano, with a voice of exceptional on the tuning -dial.And so he has tackled In the first place, the selectivity of the beauty, who will sing, accompanied on the this problem by giving the muting circuit set is improved, because in addition to the piano by Jack Clarke, the Laughing Song an additional short time-lag, which is just ordinary filtering action of the tuned input from " Die Fledermaus," and a waltz, " Spring- sufficient to prevent any signal from getting circuits, the effect of the muting circuit time of Love," by Moskowski. Actually it helps to Al and Bob Harvey are the two well-known through unless it is the one the listener comes into play. Canadian bunkhouse boys who have appeared wishes to hear. sharpen the tuning by reducing the number many times with the " Rocky Mountaineers," Ine other words, a listener is able to move of degrees on the tuning -scale over which while also from Canada come Nixon and the control fairly slowly across the tuning. each signal can be heard. Morrison,aclevercross -talkact.New dial without hearing a whisper from the As soon as a strong signal is received the Zealandisrepresented by Keith Wilbur, loudspeaker until he reaches the desired muting circuit,instead of being imme- whose brilliant imitations have previously station.Here he simply lets the control diately released, comes into action, slowly delighted listeners.Supporting this strong " stay put " for half a second, and by that at first, and then with a rush, as shown by cast will be Harry Bidgood and his Band. Popular Wireless, December 12th, 1936. 379 TELEVISION TOPICS- Collected by A. S. Clark

50 cycle hum on the Technicalities, Personalities andNewsfrom allparts of deflectors willpro- the Worldmake this "PopularWireless " feature the duce a wavy edge to HIGH-CLASS finestmedium by which readers can keep right in touch the raster or frame. with allaspects ofdevelopment intelevision, But if a strong sync. TELEVISION isapplieditwill pull the raster up WE were recently privileged to pay a, square and a wavy most interesting visit to the Ediswan picture will not be obtained necessarily. television laboratory at their Ponders It is a very similar effect to the masking End Works. We felt it was a good omen to " TELEFRAMES of slight hum in a sound receiver as soon learn right at the start that just across the Items of general interest as a programme comes through. road from the television laboratory was the "hut " in which Professor Fleming, many NO DUST ALLOWED years ago, made the first thermionic valve. IN a recent television broadcast of special- During the spraying of the fluorescent That the omen was good was well proved ised forms of artistic decoration, the compound on to the by the excellence of television announcer held up a hand - screens of cathode- the pictures we saw mirror delicately adorned on the back with raytubes,special THEMURPHYCHASSIS and the interesting figures or floral designs. care has to be taken things we learnt He remarked that the work was very fine, to avoid any foreign about the research but that he did not know whether lookers matter becoming at- work that has been, would be able to see it. Whether he was re- tachedduringthe and stillis, carried ferring to the decoration or the mirror itself process. Even on by the makers of was not clear, for as he held it up he moved specks of dust can Ediswan cathode-ray it so high that all the television screen cause bad blemishes tubes. No complete showed was his fist and a tiny bit of the on the screen because televisionreceivers handle ! they spread during for sale commercially the process of evacu- are made by this A LITTLE CLOSER, PLEASE ation during which firm, the object of It is generally appreciated that " funny - theelectrodesare thedemonstrations men " and comic turns should be greatly raised to a very high being to show us the improved by the addition of sight to sound temperature in order excellenceof the broadcasting, and that such turns should to bake out occluded various television be the very salt of television programmes. gases. componentsthey But those responsible must remember * * make. that this is largely true simply because of the additional effect achieved by facial FERRANTI Special Components play.A recent turn of this nature was RECEIVERS These include largely spoilt by the inclusion of the come- Twointeresting cathode-ray tubes of dian full length on the screen when a close- itemsrecentlyto varying sizes up to up or half-length picture would have done hand concerning the those with12in. him so much more justice. two Ferranti televi- diameter screens, sion receivers are as specialultrashort- * * * follows : _ wave receiving A SYNC. CLEAN UP A fourteen - inch valves,rectifying Television experimenters may be inter- diameter screen will valves, gas discharge ested to learn that it is by no means neces- be used on the cath- tubes,transformers sary for a perfect raster shape to be obtained ode-raytubeand and loudspeakers. before the application of picture and sync. will provide a pic- Three receivers pulses for results to be satisfactory.(Not ture ten inches by wereinoperation eight. The second is simultaneously from that a perfect raster of picture frame is How the Murphy television receiver chassis looks not desirable, mark you.) that magnetic focus- in its completed form.It will be remembered theAlexandra For instance, a certainpercentage of ingandscanning that in our November 28th issue we showed the Palace transmissions. willbeemployed, separate units for this receiver. The first of these was instead of the more an experimental * familiar electrostatic control for these two model developed in the works with the aid CABARET FOR operations. In magnetic focusing and scan- of a 240 -line film transmitter some time ning, coils of wire are arranged round the before any high -definitiontransmissions TELEVISION VIEWERS outside of the tube through which suitable were available. Burnt Sepiais the appropriate title chosen currents are passed which produce varying The second was a " super " job in which for an all -coloured cabaret show which Dallas or steady magnetic fields as required, and no expense had been spared to obtain the Bower is presenting on Friday of this week in theafternoonandeveningtelevisiontrans- these in turn influence the cathode-ray itself. best possible results.It was used in the missions.Mabel Scott, the celebrated vocalist * * * demonstration booths at Olympia during who originally sang with Duke Ellington and his band, will appear ;this may be one of her last WHAT ABOUT TELEVISION HIRE ? the exhibition this year. performances in this country before returning to The hire of receivers as distinct from hire America to join Cab Calloway's ensemble. The Excellent Results Obtained billalso includes Garland Wilson, the famous purchase has caught on very widely, and New York pianist and vocalist, who has worked there are many firms now specialising in it. Pictures on this set were certainly among with Jack Payne and his band in London. Cyril Blake, from the Barbados, will be seen and heard We wonder how long it will be before a the very best we have seen, and itis in a dazzling trumpet act.That distinguished similar service is started for television.Of noteworthy that tuned radio frequency cabaretpair,Harrisand Howell, famous in circuits were used in the vision receiver as America for their broadcasts and film work, are course, the hiring charges are bound to be also taking part. The chorus will be provided by fairly high, but there are no doubt many opposed to the more usual superhet circuit. the Sepia Chorines, directed by Buddy Bradley, This throws an interesting sidelight on the one of the leading coloured dance directors in who would welcome it who would not buy this country. a set in the ordinary way. announcement we have already made that In presenting this interesting feature, Dallas Continual free service, and a guarantee we place considerable importance on the Bower will use special scenery to create the real work on T.R.F. circuits for television which cabaret atmosphere, and televiewers will be able that the sets will be kept up to date would to imagine themselves present at a very festive be a far greater attraction where television we are conducting in our own laboratories. occasion. was concerned than where ordinary broad- The third receiver is built on lines which

-1( cast sets are in question. (Continued overleaf.) 280 Popular Wireless, December 12th, 1936.

around 3 to 4 thousand cycles too much TELEVISION TOPICS-Continued with the effect of a tiring brilliance on loud reproduction. would make it a " commercial " proposition, enough, it was slightly bluey. But then the After Alexandra Palace closed down we and uses a superhet circuit for vision recep- true white of daylight is slightly bluey in were treated to a demonstration of film tion working on one set of sidebands only. comparison with an electric bulb. transmission on 240 lines by means of (This makes theprovisionof suitably a Nipkow disc. The transmitter used " wide " circuits an easier proposition.) High Quality Reproduction exactly reproduced theBairdtypeof These two latter instruments thus enable Full advantage of thepossiblehigh transmission, and is employed to carry on the Ediswan engineers to test tubes under quality of the television sound transmis- experiments by land -line linkwhen no normal working conditions, and also to have sions is taken by the use of dual high-fidelity transmissions are on. a first-class standard against which to judge speakers.The second speaker is used to Another interesting item in the laboratory results. " smooth " the base output by staggered was a rack of six tubes undergoing a life The T.R.F. set was worked from an aerial resonances and to extend the high -note test. These were samples from various on the roof, while the superhet receiver was range.The overall response is within plus batches of tubes manufactured and are left connected to a di -pole aerial at ground level or minus five decibels of level between 90 continuously scanning under normal oper- inside the laboratory. An interesting com- and 6,000 cycles, this giving a good quality ating voltages. parison was provided between the two which can be operated at low or high One was somewhat yellow in colour, aerials when Mr. Price, who is in charge of volumes without fatigue to listeners. while the others were bluey, and we were the laboratories, started up his car just The range could be extended to be sub- interested to learn that this showed a slight outside. stantially level up to 8 or 9 thousand cycles, defect in the tube's coating, which was then Interference from the set with the ground - but this tended to increase the response nearing the end of its life. The average life, levelaerialwas we learnt, was not considerable, while IN THE EDLSWAN TELEVISION LABORATORY far short of 1,000 the added height hours. of the other aerial Finally, we saw reduced the inter- the testing rack in ference to propor- which all tubes go tions which could through every con- only be described ceivabletestfor as slight. characteristic con- stancybefore be- Colouring ing despatched. The pictures on two of the three Reliability tubes could not be We came away described as any- convinced that thingbutblack anyone who buys andwhite.The an Ediswan third had an alter- cathode-raytube native of a very for experimental slightly petunia use, or who pur- colour. chases a television Notuntilthe receiver incorpora- normal electric ting an Ediswan lightingofthe tube, has a tube laboratory w a s which is as perfect turned up was it andreliableas possible to detect modern science can any colourtinge make it. And the in the other two In the left foreground is the tube tester, the tubes being held vertically in the hole visible in the bench. Im- same goes for the mediately behind the tester are some tubes in a rack undergoing life tests.In the background, from left to right, screens, and then, are the experimental receiver, commercial -type receiver, and " super " receiver (see text).On the right is the other Ediswan tele- surprisingly " bench -type " receiver on which pictures ransmitted from the next room were seen. vision products. it and the next so that the impres-over the flicker difficulty in an sion of one has faded before theingenious way without requiring TELEVISION FOR BEGINNERS next appears. The movementsa higher frequency band by using will then be flickering and thetheir " interlacing scanning " Q. Stet ens explains the whys and wherefores only way to get rid of the trouble method.Roughly speaking, the of interlocked scanning is to speed up the rate of showingpicture is presented in two parts, of the pictures.In the tine filmeach part containing half the total this speed-up has been cleverlynumber of lines. The pictures are QUITE a lot of people are still associated with it.Those of youdone by not only increasing the "staggered " by the width of one Vi doubtful about why therewho remember the very earlyspeed of passage of the film fromline, so that they are interlaced, should be such an appar-days of cinemas will recall the18 to 24 pictures per second, butand the eye sees a complete pic- ently complicated system as the nasty flicker which was a featurea shutter cuts off the light duringture. 31.1. " interlaced scanning," and of the first films-how they gaveeach picture, giving the effect of *'hytelevision pictures can't be you the feeling that your eyes48 pictures presented each second. A Steadier Picture sentoutina straightforward were popping out of your headIt is generally agreed that this The advantage ofthis latter manner, so to speak.The answer after looking at them for a time. to their doubts isfirst that it is a minimum speed of viewingmethod is the same as that of Not Yet Flickerless separate pictures if any flicker iscutting off the light during the improves the picture, and that is to be avoided. of atine sufficient answer to the " why " ; The same trouble was present passage film-the and secondly, it isn't really anyin the early television pictures, Now in television to presentapparent frequency of the flicker 48 complete pictures per secondis doubled, and the picture thus more complicated than the straight and while the present-day ones appears steadier. Notice the word forward scan when you under- are a great improvement, we can'twould be a very difficult job, as the band of, frequencies involved " apparent," because we have not stand the principle. say yet that we are as free from really doubled the frequency.If The whole aim oftelevision flicker as the films.Flicker itselfinthetransmission would be is an optical effect due to the factenormous. As it is, the frequencywe had there would be 50 pictures developmentistoproducea range required to produce the per second, whereas there are only picture as good as a cinema pic- that the image horn the picture 50 half -pictures. ture, both in detail and in general fadesbeforethenextimagefine details of 405 line 25 pictures appearance, and so far television appears. is high, and it would be more falls short of this ideal in two ways If the film is run through thedifficult still to double it for 50 "SEEN ON THE AIR" pictures. -it is less sharp in definition andprojector very slowly each pic- appears on page 391. it has a certain amount of flickerture will have a pause between The E.M.I.people have got Popular Wireless, December 12th, 1936. 381 RANDOM RADIO REFLECTIONS By Victor King NEW USE FOR CLOTHES PEGS - TELEVISION - HANDY TOOL FOR CONSTRUCTORS

THOSE CLIPS Now and then there are technical faults AWKWARDLY PLACED NUTS AND SUPPOSE most of you who areex- in the transmission which rather tend to SCREWS 'perimenters own a bunch of crocodile lead one up the garden. One night the vision SOME of the screws and nuts in modern clips.I always have at least a dozen or so transmitter broke down completely for chassis designs are most inaccessibly lying about, many of them having leads of about ten minutes.I started in to fake placed.The other day I came across varying lengths attached to them. about with my receiver-quite unnecessarily quite an exceptionally badly located pair But for some jobs the crocodiles aren't as it turned out.Another evening there of screws.It seemed to me that the same quite so good as they might be.Their was considerable distortion on the sound mechanical ends could have been served by teeth let things slip through them or they side during a Picture Page transmission. having those screws where one could push a won't bite flat down on to the job. Still, on the whole, the B.B.C. engineers screwdriver straight down on to them. Well, I've supplemented my collection have done their job very well, and the total And yet they were tucked underneath a with one or two clips of a special kind- time of the breakdowns must reveal a much ledging so that a right-angled screwdriver home made.The sketch shows exactly smaller percentage than was the case in the was the only thing which could possibly how oneof themis early years of get at them.Of course, I couldn't find fashioned. The main TWO. PRACTICAL TIPS- blindbroadcast- mine anywhere.So I had to bend the end part of it comprises an ing. of an ordinary one over.Even so it took a ordinaryspring - type 5/ovz.9 4hiess.0-A I hope that long while to move the screws because of clothes peg. 6/0.6vi- fairlysoonthe the difficulty of applying pressure. Connect -lay You then take a small ScPleak _,/ /mac two separate Getting screws and nuts back is some- piece of springy brass systems of vision times the very dickens of a job.But a or copper and bend it transmission used little while age I acquired a gadget which in a wavy pattern so willbe merged, enables this to be done fairly easily.You that it is like a piece of for it seems to me see it illustrated in an accompanying sketch. miniature corrugated thatbothhave The one end is split and the prongs tend to iron.A hole is drilled complementary spring outwards.With this end you can through this metal and grip the slot of a screw. also through one of the The other end is also jaws of thepeg. A split, but in such a way screwwithalittle For,Yua that a nut can be held. terminal head or nut Once the screw or nut How an ordinary wooden clothes peg can be holds the metal in place adaptedforradiowork.When thepegis has been "started" and also secures the lead.clipped on to a terminal or some other point to more thanhalfthe which connection has to be made, electrical con- battle is won. But you should clearly tact is provided via the small piece of springy brass. be able to see the wholeThe gadget on the right is specially designed for No, you needn't write thinginthesketch. dealing with nuts and screws situated in awkward and tell me that there You will find that the positions.The sketch is self-explanatory. are other ways of doing clip will hold on to things most tenaciously, advantagesa n d the job.I know there but don't forget to see that the surface of disadvantages. are lots of them, includ- the metal is fairly clean. For example, ing the use of wooden E.M.I. certainly skewers and Plasticine. MORE TELEVISION EXPERIMENTS score tremendously And I am afraid I do BUT this time they weren't concerned with their Emitron not know where you can with the enlargement of the picture. Camera. No doubt buy the gadget I have I've been playing about with aerials. At my about that.They can,in my opinion, just described, though I expect quitea, home, about six miles from the Alexandra handle various outdoor scenes much better lot of you would be able to make one easily Palace, I get an extremely good signal. than the other people, and also introduce enough. I find that sufficient pick-up is obtainable such refinements such as dissolving one from a small indoor aerial consisting of a view into another, smooth " panning " and MY RADIO PLAY twelve -foot length of cotton -covered wire " fading " and so on. WHICH isn'tyet writtenandmay strung across the room.With a simple On the other hand, the Baird system not be. But thanks to all you who indoor di -pole, comprising two lengths each seems to me to handle film better, and have sent me letters of good wishes. about five feet six inches along the picture for certain types of shot their spot -light But I must make it clear that this is no rail, the signal is very powerful indeed. scanning appears to provide sharper and chef-d'antvre. Merely something set aside So all the trouble I took to fix up an brighter pictures. But then there is notice- for some of the few leisure hours I enjoy. imposing outdoor di -pole appears to have able flicker while the E.M.I. stuff is quite If I had had serious designs on writing been wasted !However, itjooks impressive, flickerless. for radio, I'd have taken up an invitation even though it seems unlikely to be needed. Between the two of them we could have sent to me by one of the very big B.B.C. Actually, I can get good pictures on any- marvellously perfect transmissions all the bosses a few months ago. thing from a few feet of wire lying on the week and every week. " You are just the sort of writer we want floor downstairs to my long, ordinary aerial. However, during these early days it isfor the radio," he wrote." Please let us There is no noticeable interference of any valuable to have a spirit of keen competi- have some of your stuff." kind.I can't get any, any old how. Which tionwith two independently operating When I told an aspiring author that I is very nice from a domestic seeing and hear- sets of engineers in constant rivalry,Pro- didn't accept that kind invitation on the ing point of view, but rather disappointing gress is bound to be rapid, though I am spot, at once and immediately, by return to me as an engineer.I'd love to have a bound to say I think British television of post, he nearly threw a fit ! nice slice of static, man-made or otherwise, already provides reallyfirst-classenter- Strange though it may appear to some to tackle. tainment. A really high spot was recently folk, I have no ambitions at all to ply my And the aerials are a mere thirty or forty achieved with the transmission of a news penina professional manner forthe feet from a busy road carrying a fair amount reel that included some exciting scenes in microphone. I get nearly all the word - of motor traffic. A friend of mine was at the Foord-Neusel fight.I'd have television juggling kick I desire by penning these first troubled by a complete modulation hum in my home for nothing else but the Movie - P.W." notes,But if the Daily Tele- wipe out. But he got over that by using a tone News. It is topical, well presented and graph " were to offer me the job of leader vertical di -pole. wonderfully transmitted. writer ....! 382 Popular Wireless, December 12th, 1936.

the frequency of the flashes will gradually increase, until ultimately there is practi- A NEON LAMP TESTER cally a continuous light, this proving that the insulation has broken down and needs replacement.A test of this character is A simple method of carrying out continuity tests on resistances, better than one with a megger. condensers, arid other radio components DETAILS OF THE PRODS THE average home constructor is some- will be evidenced by the glowing of the neon timescalled upon to undertake a lamp-a visual signal which will be quite fair amount of testing work and fault definite when the metal points of the handles tracing in connection with wireless receivers, make contact.Only about three to four vA7 / if . //4 both for himself and friends, and to accom- milliamps of current flow through the lamp plish this it is necessary to have within when alight, hence the current consumption easy reach some simple apparatus in order is negligible. to carry out the work in a reliable and expedient manner.There are many de- Checking Condenser Insulation vices available, a pair of telephones and The handles prove very useful for getting a dry battery being a useful adjunct for at the internal wiring of a wireless set when Blass many of the tasks. making sure that all connections are intact. Coils, condensers, resistances, etc., can be Fig. 2.Details for making the test prods.In- D.C. Mains or Batteries Suitable treated similarly,while in the caseof sulated prods of this type can also be bought It is quite a good scheme, however, to take condensers, especially fixed ones, a test of ready-made. advantage of the interesting properties of this character is very searching.If the By means of the neon lamp tester it is the neon lamp, which in one of its most 'condenser insulation is imperfect, and the a simple matter to trace such leakage as in familiar types is the " Osglim " made by test handles are left under the condenser the insulation of a valveholder, between. the G.E.C.This lamp can be used for terminals for, say, a couple of minutes, a grid and filament.This leakage may not continuity tests in preference to the tele- flicker of light will be noticed in the lamp. be apparent in the ordinary way, but may phones and battery.Those constructors With the progress of another few minutes still be enough to cause poor results. who have D.C. electricsupply in their houses can duplicate exactly the arrange- ment to be described, and in those cases where such a sourceofvoltageisnot available, ordinary dry batteries with a total voltage of about 180 willsuffice. FURTHER S.T. 800 SUCCESS Fig. 1 is the simple circuit arrangement, the Osglim lamp being held in a batten lamp holder mounted on a small wooden base. IN BIRMINGHAM Fig. 2 shows the details and necessary Dear Sir,-Enclosed herewith is a further report of reception on the S.T.800.You dimensions for making a pair of testing will notice that I succeeded in getting both Tokio and Sydney with very little trouble. prods for use with a unit of this type. The consistency of W 2 X AD and W2 X A F has been wonderful, and I could easily invite anyone to hear them whenever they are radiating.I shall continue to send a report in each week.-Yours sincerely LESLIE A. PERRINS. THE CONNECTIONS USED 101, Sycamore Road, Aston, Birmingham, 6. Sunday, October 25th. -6.15 p.m. (16 m.) : W L A, Lawrenceville, N.J., with G A S, Rugby. G A S giving a special pianoforte programme from London for C.B.S.I heard this at R9 after it had crossed the Atlantic twice (very little difference in quality or strength to programme originating in New York).Announced IV L A on 18,408 kc. 7 p.m. (16 m.) : W 3 X A L, Boundbrook.Relay from Grand Central railway station. Taken into Ticket office, Pullman Reservation office, etc.,and was told that they operated 11,000 miles of line.This was part of the " Magic Key " programme.Also heard Mr. Goodman, kettledrum expert. 10.50 p.m. (31 m.) :Rio de Janeiro.Call and " Good -night, Vienna "-orchestra. Fig. I.The connections are very simple, the W 2 X A F.Lennox programme, " Painting the Clouds With Sunshine " and Smiling tester consisting of the lamp and two test prods Ed McConnell.Catholic Hour. D J A and D J N.Concert. connected to a source of D.C. supply. Monday, October 26th -8 p.m. (19 m.) : W2XAD. "Pepper Young " programme. Announcer,SpencerBailey.Oxydol-" Ma Perkins."Crysco-" Vie and Sade." The thick ebonite tube should be screwed (Red Network.)9 p.m. (31 m.) : W 2 X A F.Concert.Tom Mix. . Wlpaties-Jack internally for about in., and the brass Armstrong. rod screwed externally for the same length, Tuesday, October 27th. -8 p.m. (19 m.) : W 2 X A D."Pepper Young," etc. W 8 X K Concert.10.15 p.m. (31 m.) : W 2 X A F. Tom Mix and Jack Armstrong programmes. so that the brass screws into the ebonite Wednesday, October 28th. -8 p.m. (19 m.) : W2XAD. "Pepper Young " etc. and is held rigidly.Bare the insulation 9 p.m. (31 m.) : W 2 X A F.Orchestra. Tom Mix. Jack Armstrong. 10.45 p.m. Miss from one end of a length of flex and pass Fleming (soprano) from Australia :" Oh, Could I But Express in Song."Orchestra : the ebonite tube over the end. Thread the " Dance of the Desert Girls."Miss F., talk on Australia.11 p.m. Education Series : wire end through the **-in. hole in the brass 1600 A.D., " Galileo and the Stars." rod,solderingit in place in the small Friday, October 30th. -7 p.m. (31.48 m.) :Tokio.Talk. (19.57 m.) : W 2 X A D. channel shown at A.The ebonite tube (19.66 m.) : GSI (R6).(19.72 m.) : W8XK (R7).7.30 p.m. (19.8 m.) : Tokio, JZK. can now be screwed over the rod and the Orchestra with male and female vocalists.Dance Music and Call.9 p.m. W 2 X A F. handle is complete.This process must, of Orchestra and vocalists :" One Night of Love," " Alice Blue Gown," etc.Stocks. course, be duplicated for the other handle, Orchestra from San Francisco.10.30 p.m. Tom Mix. Jack Armstrong.Miss Fleming then the pair of free flex ends should be (soprano).11 p.m." Legend of a Widow Duchess," " The Norseman "-Vocal Quartet bared of insulation and placed under ter- 11.30 p.m. News. Announced that Roosevelt would speak at 10 p.m.E.S.T.Spaiish Programme.Orchestra :" Did I Remember." minals provided on the lamp block. As will Saturday, October 31st. -7 p.m.: W 2 X A D.Baseball Match.11 p.m. W 2 X A F. be seen,the construction is particularly Tango orchestra. simple, and the constructor will now have Sunday, November lst.-7.20 a.m.V K 2 M E, Sydney. Concert and Call.1.15 p.m. in his possession a piece of test apparatus (31 m.) :Jeloy.Religious music.Tenor and Organ and Address. (19 m.) : D J L and which will find application in nearly all his D I It (R9), Military Band.(40 m.) (Phone) : G 6 Z A, G 5 P H, G 8 C D (R8). testing work. 2.30 p.m. (31 m.) : D J A.Wagner Concert :Overture, " Flying Dutchman."G S B. In actual use the electric -light plug must Rispah Goodacre (contralto). W 2 X A D.Concert.The Famous Trio. W 3 X A L. be placed in an ordinary lamp holder, and News. W 2 X E.Concert forChildren. W 2 X A D.The famous Trio :" Just a the insulated portion of the handles held Wearin' For You," " Cherry Ripe," " Under His Wing " (hymn). one in each hand.Continuity in a circuit 4 Popular Wireless, December 12th, 1936. 3S3 LEARNING FRENCH THROUGH YOUR RADIO Part 40 of the special language series contributed exclusively to"Popular Wireless" By S. C. Gillard, M.A.

PER-IR, CHER-IR, FLEUR-IR, BRAND- The FOUR COMPOUND TENSES should IR, TERN-IR, VERN-IR, EMBELL-IR. present no difficulty whatever. Their PRESENT PARTICIPLES are J'aifini I have finished etc. respectively : J'avais fini I had finished FINISS ANT (finishing), PUNISSANT etc. J'aurai fini Iwill have finished (punishing). ACCOMPLISSANT (accom- etc. plishing),FOURNISSANT(furnishing), J'aurais fini I would have finished NOURRISSANT (nourishing), BANNIS- etc. SANT (banishing), PERISSANT (perishing) NorshouldTENSES 8 and9-the CHERISSANT(cherishing),FLEURIS- FUTURE SIMPLE andtheCONDI- SANT (blooming), BRANDISSANT (brand- TIONAL. You remember how we formed ishing), TERNISSANT (tarnishing), VER- these two tenses in an -ER verb.Just NISSANT (varnishing), EMBELLISSANT the INFINITIVE plus CERTAIN TERMI- (embellishing). NATIONS.Itisthe same here.(See Their PAST PARTICIPLES are just as Part 21.) Here is a fine set which will bring in not only easily formed.The PAST PARTICIPLE Je finir-ai fin-eer-eh I will finish the French and other Continental broadcasts, but ending here is NOT an E, as in the case tu finir-as fin-eer-ah etc. also transatlantic transmissions as well.Itis Look ! itfinir-a fin-eer-ah thelatest11.M.V.all -wave,universal mains of the -ER verbs.It is just -I. nous finir-ons fin-eer-o(ng) radiogram, and costs 25 guineas. FINI (finished), PUNI (punished): AC- vous finir-ez fin-ear-els COMPLI (accomplished), FOURNI (fur- its finir-ont fin-eer-o(ng) nished), NOURRI (nourished), BANNI Je finir-ais fin-eer-eh I would finish ALTHOUGH you can go a long way in tu finir-ais etc. French on1st Conjugation verbs (banished),PERI(perished),CHERI itfinir-ait (i.e. Infinitive-ER), you can't go (cherished), FLEURI (flourished, bloomed), nous finir-ions fin-e;;-e'o(ng) the whole way. BRANDI (brandished), TERNI (tarnished), vous finir-iez fin-eer-ieh VERNI (varnished), EMBELLI (embel- itsfinir-aient fin-eer-eh There is another class of French verbs- I am going to give you now a number of nothing like as big as the -ER class, of lished). verbs like FINIR besides a few phrases coursewhere the INFINITIVE ENDS The big thing to remember about these IN -IR.It is about these verbs that I verbs is that the STEM of each contains or sentences to illustrate their meaning. this ISS syllable.That is to say, Learn as many of them as you can by wanttotalkthisweek. WE MUST heart. LEARN HOW TO CONJUGATE THEM. The STEM of FINIR is FINISS- PALI R (palissant, OM, to turn pale. There are the same NINE tenses as before, PUNIR PUNISS- Ses joues ont pillHis cheeks have lost their colon,. with the same differences -in meaning for ACCOMPLIR ACCOMPLISS- Son etoile palissaitHis star was waning. FOURNIR FOURNISS- EMPLIR (emplissant, empli).to fill, to throng. each TENSE. So apply tothese new NOURRIR NOURRISS- La foule emplissait les ruesThe crowd thronged the verbs the knowledge you have of -ER BANNIR BANNISS- streets. PERIR PERISS- GUE RI R (guerissant, gueri) to cure. verbs, and particularly the way in which CHERIR CHERISS- Je me suis gueri de cette mauvaise habitudeI have the TENSES are used. FLEURIR FLEURISS- cured myself of this bad habit. Now, -IR verbs can be divided into BRANDIR BRANDISS- SU RGI R (surgissant, surgi) to rise,to Coma into TERNIR TERNISS- view. TWO classes.One class has an extra VERNIR VERNISS- Une forme surgit des tenebresA figure loomed out syllable " -ISS " in the Present Participle. EMBELLIR EMBELLISS- of the darkness. APPLAUDIR (applaudissant, applaudi) to applaud. The other HASN'T. You must master this ISS business, if Le resultat fut vivernent applaudiThe result was I will call the one class the ISS class. you hope to conjugate these verbs in -IR loudly applauded. The other, the non-ISS class. L'acte de D. est tres applaudiD.'sactismuch correctly. applauded. OUR OWN LANGUAGE HELPS US Let me now give you TENSE No. 1 of ETA BLI R (etablissant, etabli) to establish. VERY CONSIDERABLY IN DECIDING L'aviateur Jim Mollison a etabli un nouveau record FINIR. Note where it differs from TENSE The airman Jim Mollison hasestablisheda new WHETHER A FRENCH -IR VERB HAS No. 1 of an -ER verb.(See Part 18.) record. THIS ISS IN THE PRESENT PARTI- GA RANTI R, (garantissant, garanti) to guarantee. Je fin -is fin-ee I finish La qualite de nos pendules est garantieThe quality CIPLE. tu fin -is fin-ee etc. of our clocks is guaranteed. Look at the following English verbs : 11 fin -it fin-ee FREMIR (fremissant, fremi) to vibrate. nous tiniss-ons fin-eess-o(ng) Les cordes d'un violon fremissentThe strings of a TO FINISH, PUNISH, ACCOMPLISH, vous finiss-ez fin-eess-eh violin vibrate. FURNISH. NOURISH, BANISH. PER- itsfiniss-ent fin-eess AGIR (agissant, agi) to act. Vous agissezmal enversmoi You behavebadly ISH, CHERISH, FLOURISH, BRAND- IN TENSE No. 2-I was finishing-the towards me. ISH, TARNISH, VARNISH, EMBEL- ABOUTIR (aboutissant, abouti) to converge on. STEM FINISS- is used throughout. Again Les grands reseaux de chemins de fer aboutissent a LISH. compare this Tense with the same Tense ParisThe main railway systems converge on Paris. It is this ISH termination that I am of an -ER verb. Un souterrain reliant l'auberge avec le Palais du L, chiefly interested in.Yes, this ISH termi- aboutissait ici.A subterranean passage joining the nation is nothing more than the ISS syllable Je finiss-ais fin-cess-eh I was finish- inn to the palace L, ended here. tu finiss-ais ing etc. EBLOUIR (eblouissant, &lout) to dazzle. I have been talking about.' ALL these itfiniss-ail II le fit pour nous atonicHe did it to date us. nous finiss-ions fin-ress-e'o(ng) Elie a une beaute eblouissanteShe has a dauling English ISH verbs are French words, too, vous finiss-iez fin-eess-e'eh beauty. but for the English ISH we find the French itsfiniss-aient fin-cess-eh RE USSI R (reussissant, reussi) to succeed. ISS, at least in the PRESENT PARTI- J'ai reussi a mon examen / have passed my examin- TENSE No. 3-I finished-is ation. CIPLE and certain of the TENSES. RALENTIR (ralentissant, ralenti) to slow down. Let me give you the French INFINI- Je fin -is fin-ee Ilinislled Le train ralentissait.The train was slowing down. to fin -is tl etc. SU HI R (subissant, subi) to undergo. TIVES first : itfin -it Les six nouveaux croiseurs subissent egalement des nous fin-i met (in-ce"m retards sensibles.The six new cruisers are suffering FIN - TR, PUN - IR, ACCOMPL - IR, vous fin-ites fin -eel from appreciable delays. FOURN-IR, NOURR-IR, BANN-IR, ilsfin-ireni fin-eer REAGIR (reagissant, reagi) to react. 381 Popular Wireless, December 12th, 1936.

resulting pulse of voltage passes through Cl on to the deflecting -electrode of the CHEAPER TELEVISION cathode-raytube,causingtheelectron stream to sweep across the fluorescent Details of a new tune -base circuit in which one valve controls screen.This process is, of course, repeated at the arrival of each " line " signal. both line and frame scanning A second circuit, similar to the one shown in Fig.1,is meanwhile generating the " framing " oscillations required for the By J. C. JEVONS second pair of deflecting -electrodes inside the cathode-ray tube. TELEVISION has begun officially, but tube. Originally the " soft " or gas -filled with the price of a complete sound - type of C.R. tube was preferred because the A Single Valve Arrangement and -picture receiver round about £100 focusing of the electron stream took place By contrast, Fig. 2 shows how a single the prospect of bringing it into the home more or less automatically.But later prac- valve, V, can be arranged to supply both does not look too rosy.At the figure tice favours the use of the " hard " or the line and framing oscillations at the same quoted a number of the sets sold will go to evacuated tube which, when fitted with time.The valve is fitted with two anodes, the big departmental stores-who are using focusing -electrodes,produces' a sharper one on each side of the cathode, and a television as an advertising stunt-and to " spot " and clearer common control grid. the more enterprising hotels and restaurants. picture detail. NORMAL PENTODE FEED The condenser CL for In addition, therewill be private sales A similar difference line - scanning and to customers who do not have to count of opinion exists in the condenser CF for the cost of sharing in the latest novelty. connection with the framing areboth time -base or scanning charged up from the Simplifying Design circuits used for pro- H.T. supply through But when all is said and done, the idea ducing the line and constant - current behind television is to provide a new service framingfrequencies. diodesD, and are for the benefit of the public at large-on Some designers prefer discharged across the more or less the same lines as the broadcast to employ gas -filled two separate anode - programmes. Listeners' money is being discharge valves of the cathode paths inside used for the experiment, and this can only Thyratrontypefor the valve. be justified on the assumption that those generatingthere- Fig.1.-A typicalpentode -fedgas -discharge Both sets of syn- who pay the price will, sooner or later, " get quired saw - toothed sweep circuit. chronising -signals are the goods " on something like reasonable oscillations ; whilst applied to the grid terms. others pin their faith to the " hard " valve, of thevalve across the same pair of The firstthing we want is a bigger which can be used to produce the same type terminals S.The line signals discharge market.If the programmes catch on- of " peaked" impulse. Then, again, one can the condenser CL at a rapid rate, through even with the present limited appeal-and either " earth " one of the deflecting elec- one sideof the valve, to supply scan- many more sets are sold, then the applica- trodes inside the cathode-ray tube, and ning -voltages to the P1 deflector electrodes, tionof mass production methodswill apply the fulldeflecting -voltage to the whilst the framing signals discharge the enable manufacturers to make a big cut in other, or, better still, drive both electrodes condenser CF, at a slower rate, through their costs. in push-pull about a common neutral point. the opposite side of the valve. The slower - Another factor that may help is the pros- But whatever kind of time -base circuit is oscillations are fed to P deflector electrodes pect of being able to simplify circuit design. employed, it is standard practice to use two which control the framing of the picture. At present a sound - separateoscillators, The difference in the value of the two and -picturereceiver A SIMPLECIRCUIT one to give the rapid condensers is sufficient to, keep each set of runs to over twenty line " drive," and the oscillations distinct, though as an additional valves-to say 0 Mr other to provide the safeguard one set of synchronising signals nothing of the t slower " framing " may also be made stronger than the other. cathode-ray tube. The frequency. Here it latterisa particu- o wouldseemis an* larly expensive item, opportunity for * because although an simplifyingmatters GIFT -BOOKS FOR old -stager in the a little by arranging laboratory, it is only foronevalveto THE MANLY BOY in swaddling clothes generate both these * as appliedtotele- frequencies. EVERY lad of to -day is interested and mysti- vision. In other words, fied by the marvels of modern science. itstill offersplenty 0 Line -Scanning The BOY'S BOOK OF EVERYDAY of scopefor better Fig. 1 shows the SCIENCE (6s.) is a book that will not only and cheaper methods $ kind of circuit that explain how and why things work but will also of manufacture. T is now being used for create interest in important and less -known Valves, too, have by producing one set of sides of science.It explains how a dam holds no means reached the oscillations, say up 500 million gallons of water, how the pris- rock bottom plice at those used for line - matic binoculars work, how railway signals which they can be Fig. 2.-The two diode valves and dual -discharge scanning. The main operate, and so on ;the book is illustrated produced and sold at tube seen here form a complete double time -base. condenser C is first by some hundreds of remarkable photographs a profit. charged up at a and drawings.In addition to these fascinating features there are safe and simple home experi- A television set is necessarily a pretty steady rate from the high-tension supply ments, and the true stories of great inventors complicated box of tricks.In the first place through a pentode valve P. A blocking and discoverers. No boy who likes engineering it has to handle two sets of signal-audio condenser CIkeepstheD.C.voltage and science should be without this big -value and visual-and feed them both to separate offthedeflecting -electrodesinsidethe gift -book. reproducers. Then it has to pick up two cathode-ray tube, though it passes on the sets of synchronising impulses, separate changes in voltage caused by the discharge MYSTERY AND ADVENTURE them out from the signals proper, and put of the main condenser C. CHUMS ANNUAL (8s. 6d.) is too well known to need introduction. This new 416 -page issue them to their proper job of work.Finally, As the voltage across C increasesit is as OM as ever.It contains book -length there is the time -base circuit for scanning, reaches a value close to the breakdown stories of adventure and mystery, more than which is an " extra " in every sense of the point of the discharge valve D (which is 35 short stories of all descriptions, pictorial word. shaded to show that it is gas -filled).The articles, hundreds of illustrations and four There are two schools of thought as toarrival of a " line " synchronising -signal magnificent colour plates.There are weeks of the best way of projecting the picture on to then gives the finishing touch, and D spills healthy entertainment in this book.It is the the fluorescent screen of the cathode-ray over to short-circuit the condenser CThe gift -book par excellence. Popular Wireless, December 12th, 1936. 285

COULDYouCROON? By Suzanne Botterell Suzanne Botterell is only twenty-three, but she has already made a name for herself on the air, and has sung with Al Collins, Lew Stone, Sydney Lipton, and Carroll Gibbons.

THE vocalist in a dance band probably can.But how on earth can 1 gets more fan -mail than the leader you give a sincere interpre- and the rest of the band put together. tation of a song when you're But for all that he or she is regarded as chiefly concerned with read- * quite an unimportant part of the musical ing the notes ?It'safter unit. you've learned a song that In America the vocalist is catered for you can really interpretit, in the same way as the star instrumental- and, if you get no time to ists, and is the centre of attraction whilelearn it, the public are get- the vocal chorus is being taken.In this ting an insincere version that country, however,I don't think I am can hardly be satisfactory. putting it too strongly when I say that You may be surprised to the tendency isfor the vocalist to be learn that the leaders choose regarded by the band as a pleasant but the tunes for their vocalists. rather unfortunate sort of a nuisance. The vocalists have very little say in what they want to sing. The Spirit of a Number Ask any dance -band vocal- They take up the attitude that it's their ist how much say he gets in instrumental music that makes the dance choosing his numbers, and band what itis,and thevocalist, by you would be surprised at Bliss Botterell thinks tere is no such thing as a crooner.She main - attracting attention from the instruments, the answer. Usually,the tains that she heself is what is known as a swing -singer. is only wasting so much valuable time. leader chooses, and chooses However, the public and the publishers well, but, frankly, I think the vocalists definingthisextraordinary thing called want vocalchoruses,sothe musicians could choose material more in keeping with " swing."As I don't pose as an expert, I have to put up with them, but they go their own individual styles if they were don't want to cross swords with them. along in their own sweet way all the time given a freer hand.I'd like to pay a com- I'll put it like this, though, that I under- the singer is doing his or her job. pliment, by the way, to Al Collins and Lew stand " swing "as a free interpretation What is, that job exactly ?Not only Stone, who were both particularly thought- which is so sincere and in keeping with a to sing the lyric and so explain what the ful in this respect. number that it communicates the rhythm song isall about, but to interpret the Vocal choruses were always matters of and feeling of that number to the listener. spirit of a number.I think that the vocal the greatest importance to Lew Stone, and The Negroes have swing in their blood ; chorus should get over to listeners the while I was singing with his band at the that is why the raucous trumpet notes of mood and atmosphere of a song, as well Cafe de Paris he and I would have long Louis Armstrong produce such an inexplic- as itsstory."But how can you yourself conferences about the numbers I was to able feeling of exhilaration in the heart correctly interpret the real essence of a do, and the spirit in which I was to do them. of a listener, and why singers like Ethel number if you have only seen it for the first Lew is that rare sort of leader-a really Waters and Billie Holiday can produce time a few minutes before you are supposed sensitive musician-and any interpretation such a wonderful effect by rhythmic impro- to broadcast it ? that was out of the spirit of a number was visation round a melody. Oh, yes, it often happens that way. A anathema to him. Likeallnew catch -phrases,though, rush orchestration is being prepared for a " swing "isbecomingmisapplied,and band of a piece which the leader happens What is a Crooner? people think thatif you shout " vo-de- tolike.The arranger, working against And now for the question which has long do 'and " hotcha-cha "long and loud time (aa they always do in this hectic been a vexed one.Are we dance vocalists enough, you are a swing singer.Take it profession !), turns up with the parts just really crooners ?What is a crooner, any- from me that the essence ofswingis before the band is due to go on the air, way ? restraint.The finest Negro swing -instru- and you are handed a vocal chorus that Personally, I don't think there's such a mentalists produce the maximum of effect you have never seen or heard of in your thing as a crooner, but the phrase isn't as with the minimum of notes, and there's lifebefore.Well,it'sall in the game ; uncomplimentary as is often made out to no reason why a singer should clutter up if the song isn't your type, or is written in be the case,You see, when broadcasting a song with meaningless" scat." an awkward key, there's no time to com- with dance bands came in, Jack Smith, What itall boils down to is that the plain. the Whispering Baritone, introduced a new vocalist in a dance band has a much bigger style of singing to take full advantage of and more important job to do than people Reading the Music Direct the peculiar qualities of the microphone. give him (or her) credit for. The band runs it through once or twice, Instead of standing well back and singing Lots of people can sing, but can they sing and you get the hang of the tune, then in the good old ballad style, he came in through a microphone?Can they sing a the red light starts flickering to tell you close and whispered into the microphone. wholechorusofmaudlin words with that zero hour is here.With your heart Well, that was the beginning of crooning. sincerity and feeling ?Can they express palpttating you hear the leader announcing, Nowadays it is even more difficult as the the rhythm of a tune without detracting We have pleasure in introducing a new style has been improved upon a good deal, from its spirit and meaning ?Can they tune which will be sung for you by Suzanne and there is a great technique to be learned receive loads of fan -mail until they think. Botterell," and you take a firm grip on before you can hope to be an expert at it. that they are real big shots, and then find youpself and hope for the best. Actually, I am what is known as a swing - themselves treated as very small beer by Of course, if you want to sing with a singer.Swing -singing is my pet subject, the bands with which they sing ?Could dance band, you have to know something but I don't want to talk much about it, you do all that ?If so, then band leaders about music, so most vocalists can read because all the jazz -experts of England and are looking for you.Such people are hard music as accurately as the instrumentalists America have recently been engaged in to find. SS6 Popular Wireless, December 12th, 1936.

FROM OUR READERS IF IRON BECAME NON-MAGNETIC The Editor, POPULAR WIRELESS Talking of " S.T." sets reminds me of an incident It is interesting to dwell on which occurred only yesterday.I was discussing an Dear Sir,-It is perhaps unnecessary to order for a kit of parts for the latest S.1'.800, and when remindreadersof" P.W."thatiron, thepossibilitiesofwhat I mentioned to the dealer that the complete kit with valves was only £4. 14. 0, it would have done Mr. Scott - whilst being one of the most plentiful and might occur if this supposi- Taggart good to see the look of complete disdain on cheapest elements, plays a great part in the dealer's face.He looked at me as much as to modern electrical engineering, and is thus tion, raised by a reader, took say :" You poor fool, expecting to get a set with valves, four valves at that, for £4. 14. 0 ! " of vital importance to the industry to -day. place Of course, this man lived in a wireless world made Indeed, during the Faraday Centenary up of pieces of furniture beautifully polished from 12 guineas upwards.The innards mustn't be men- celebrations a few years ago, some stress tioned.He simply couldn't grasp the fact that it was was laid on the fact that the whole structure possible to build a set which would tune in the ends purchase the record referred to ? (I do not, of course, of the earth for under £5.However, I was patient of our modern civilisation depended upon mean the one recorded only a few months ago by a with the poor fellow and convinced him that £4. 14. 0 the magnetisable qualities of iron.It was well-known firm of record manufacturers.) did include four valves ! pointed out that if iron were suddenly to Also, I am of the opinion that no second record is There does seem to be a total lack of interest now used, as from my own observation of this appre- among most radio dealers to help constructors to lose its power of becoming magnetised all ciated interval signal,it seems to indicate the two obtain the necessary components.But this will not the world's power stations,allitstele- records are now reproduced as, or moulded into, one. prevent enthusiasts ---and the thousands of " Popular Yours faithfully, Wireless" readers are enthusiasts-from building their phones and wireless sets, all its tramcars A. W. HARVEY. own sets, and so help them to carry on one of the and electric railways, all apparatus in which 7, Victory Road, Wendover, Aylesbury. finest hobbies in the world. iron played the role of a magnet, would Yours faithfully, T. E. PRESTON. become inoperative. In short, that this one AND THE ANSWER 6, Treaford Lane, Birmingham 8. quality of iron was necessary not only for The Editor, POPULAR WIRELESS. P.S. HeartiestcongratulationstoMr.Scott - Dear Sir,-May I encroach on your space to have Taggart on his great achievement in the S.T.800. the success of the electrical industry, but the final word about " Bow Bells" ?Referring to for civilisation itself. the letter from Mr. A. H. Bartram in your November 14th issue,I would Point out that the record(s) WHERE TO GO Iwill admit thatitis mighty con- used as the present-day B.B.C. interval signal is not The Editor, POPULAR WIRELESS. venient to be able to use iron so liberally the originalrecording mentioned by your corre- Dear Sir,-I was surprised to read in " P. W." spondent.. Oct. 17th issue,the articleof " A Novice."It and efficiently as we do to -day, but the 1. That disc was Columbia 4052, but the new re- almost made me lose my temper and I write you to only effect of the sudden failure of iron's cording made duringMarch, 1936, isColunibia inform him where to obtain " service."However, DB.1637 and is the one now in exclusive use.The in a later issueI saw Donald T. Kear was of the capacity to be magnetised would be a record was made by a mobile recording van at, of same opinion. period of inconvenience, hardly the collapse course,St. Mary -le -Bow Church, Cheapside, and May I have the pleasure of informing them that the chimes are the Whittington Chimes, i.e., the there are 1,200 qualified service engineers in Great of the whole of civilisation.Such is the actual chimes Dick Whittington is reputed to have Britain.All you have to do to get first-class service genius of man, thatif this calamity did heard, according to tradition. and a fixed charge for each job is to call in a " Radio happen (not that there is any likelihood of Your faithfully, Manufacturers' Service Engineer." If you don't know D. ALDOUS. of one in your district write to: Radio Manufacturers' it doing so, for so far as we know to -day Horns Road, Ilford, Essex. Service Ltd., Perivale, Greenford, Middlesex, and the elements of which iron is the secretary will send you the name of the nearest engineer. one are absolutely permanent These men do not charge any price inalltheircharacteristics, as the cost is made out on a sheet for ofthe then,. Here area few of them. with the exception VIENNA'S NEW RADIO HOUSE Repairing and cleaning switch con- heaviest elements which are tact, labour only,5/-, executed on spontaneously breaking down) dealer's premises ;7/6 at customer's home. Rebalancing, labour only, 7/6, he would at once set about executed on dealer's premises ;10./ - findingasubstitute,with at customer's home. On top of this every job is guaran- everyprospectofsuccess. teed for 90 days. There would spring into being Iagree with D. T. Rear that new ways of building dynamos, there are a lot of dealers who know nothing about wireless, but they are new ways of intensifying the slowlybeingpushed outofthe fields.After all, it is the wire trade, also the " A.V.C. salesmen." However, to have a good job done, carrying the current that does do as I say, it will only cost you a the work,theiron merely 1.1d. stamp. servestoconcentratethe Yours faithfully, J. R. CLEMENTSON. magnetic field. Coulty Farm, Chirk, Wrexham. Even to -day we have the THE OTHER SIDE moving coil loudspeaker, with The Editor, " Popular Wireless." its coil wound on an aluminium Dear Sir, --With referenceto the former from which ironis article on " Service," by Mr. D. T. Hear,intheNov. 14thissueof wholly absent. " Popular Wireless."Mr. Kear states But can youpicturea that he is able to explain why dealers do not give service.Maybe there are world without any magnets ? dealers who are incapable of servicing After all, we know little or receivers, but the majority can and,. nothing about what causes a will give serviceif the customer will' A view of the new Radio House at Vienna, which is at present under state what he wants and iswilling metal like iron to become a construction.It is expected to be finished about the middle of next year. to pay for the service. magnet, and another metal I have been in this service business for nearly eleven years and find that like copper not.Nor do we the majority of our customers want know why two so-called non- their receivers servicing without the TOO GOOD TO BELIEVE cost of new parts.This is the type of thing we have magnetic elements like nickel and aluminium The Editor, " Popular Wireless." to deal with :" Please patch it up, we don't want should become magnetic when combined. It Dear Sir,-May I be allowed to give hearty support to go to any expense," or, "It only wants cleaning and lets us see, however, on what a thin thread to your correspondent Mr. Donald T. Kear in his adjusting, we have only had it two years." remarks regardingservice -salesmen. Itreallyis We have even taken out faulty parts and shown our civilisation hangs at the present time- amazing to hear the rubbish whic h some of these them to customers and stillthey will not believe the more or less haphazard re -arrangement of people talk when you visit a wireless shop for an odd that a new part is required.What are we to do in component. I am quitesurethat most regular cases like these ?The other type of customer is molecules about which we are almost en- readers of " Popular Wireless " could simply floor the one who says, " It has been done by Mr. So and So, tirely ignorant. these alleged technicians on radio matters. . he is a very good man, but hasn't the time to do it They are always so anxious to put purchasers off this week."On taking the set down, we find a Yours truly, with something other than what one really requires, terrible mess nine times out of ten, wrong condensers, WM. NIMMONS. essuring you that it is just as good as the article you too small wattage resistances put in and even pieces 7, Ha zelfield Street, Belfast. originally asked for. of string to hold parts together, the soldering evi- Of course, we know there are some components dently having been done with a crowbar instead of THAT BOW -BELLS RECORD which have suitable alternatives, but in the case of a soldering iron. The Editor, " Popular Wireless." the wonderful " S.T." sets which you have given Dear Sir,-And yet one more note respecting Bow us for some years now, I really think itis advisable (Please turn to page 388.) Bells.Can your correspondent say if it is possible to to stick to the author's specified parts. Popular Wireless, December 12th, 1936. 387

DON'Tlet"PIZ VS and CRAC1C IHE OLD VALVE BROTHERS" spoil your CHRISTMAS entertainment

DON'T let old valves ruin your Christmas programmes.Replace them with OSRAM VALVES-the Tonic to any set.If you will write stating the make and type of set you have, we shall be pleased to cure your radio troubles, and will advise you on the correct Osram Valves to use.You will be amazed at the difference that Osram Valves make. MADE IN ENGLAND eivastote tos Tekvic 112asui

didvi.of The GeneralElectricCo., Ltd., Magnet House, Kingsway, London, W ' 3S6 Popular Wireless, December 12th, 1936.

just tune from 46 to 50 m. any night when conditions FROM OUR READERS-Continued are fairly good, and try to count how many stations use a gong for a signal.Most of these stations aren't content with having, say, one stroke on a gong, but When we meet with this kind of thing, can you ment, with a really simple, inexpensive and efficient they have one, two and sometimes three, using them wonder atthedealernotinterestinghimselfin set, and having followed his designs, I am positive one after the other with announcements sandwiched " service." Inconclusion, ifpeoplerequiring that I am only one of thousands who are betting on in between. This makes identification very difficult service would only pay more attention to the articles the same winner. and sometimes impossible.Whereas If each station published in " Popular Wireless " they could manage Now all you enthusiasts, keep on studying your had a different signal identification would be easy, without the service engineer and learn enough to do blueprints andinstructionsuntilyou thinkyou as any station couldn't use more than say one stroke their own servicing. know them from memory, and then read them again or two strokes on a gong, and would be unable to Wishing you, your staff and the " Popular Wireless " and you'll learn just a littlebit more.Shortly I use them both together. every success, hope to give you the result of my little competition Although it seems unlikely that this scheme will Yours faithfully, with the superhet.Wishing " P.W." its continued be taken up it would be interesting to have other H. G. FROGGATT. success. Yours sincerely, readers' views on the subject. 17, Spencer Street, Mansfield, Notts. W. J. L. L. Yours faithfully, 87, Glenwood Gardens, SUPERHET v. Ilford, Essex. HARRY LADNER. STRAIGHT 10a, Mulgrave Street, Plymouth, Devon. The Editor, AN INTERVAL - POPULAR WIRELESS. WHO WANTS A GUINEA ? SIGNAL IDEA WHY ?OH, WHY ? DearSir, Ithas Each week an award of one guinea is presented to The Editor, The Editor, " Popular Wireless." always beenakeen POPULAR WIRELESS. Dear Sir,-I wonder if some, or one, of our technical subject for arguments the sender of the letter which, in the opinion of Dear Sir,-There has friends will enlighten a poor, dumb Englishman, why astothemeritsof the Editor, is the best of the week.This week it beenalotof con- it is possible to buy American valves (sorry, " toobs "), straight sets v. super- troversy about interval mains types, too, at five to six shillings, in this country? hets, the latter being goes to Mr. W. Nimmons. Now what about you ? signals from timeto I know some of the answers beforehand, here goes. considered more power- Why nothaveashot ? Remember, everyone time, but what most " They are no good." " Ah! ah! Have you ever tried ful for the same number stands an equal chance and any radio topic what- listeners seem to over- them? " " They are rejects."(That's why the manu- of valves. look is the factthat facturers put their name on them.)" They are inferior This is a very unfair ever-practical, opinion, or experience-is suitable these signals are mainly to ours."They should be, really, but curiously they claim when the valve material. for identification pur- are not. typesareconsidered. poses.Of course, if it Then we have American sets selling at 13. 10. 0 Take the normal * *happens to be pleasant TRFs (mains) superhets, five or six valves ;A.V.C., straight set, consisting to hear as well as pro- 16-50, 250-550, 1,000-2,000 metres, splendid jobs, of S.G., Det., L.F. and Power or Class B. viding an easy means of identification, so much the too,£6. 10. 0 to £10. The four -valve super uses a mixer in place of two better, but, personally, I think this is of secondary For £10 you can get a real top-notch first-class normal valves ;S.G., D.D.T. instead of two valves, importance. set. Admitted we have one manufacturer who puts and Power or Pentode.Total equal to six valves in It is fairly simple to identify stations on the out a decent job at about £6. 10. 0, but it's not a the straight, hence the extra power. ordinary wavebands-i.e., long and medium wave five -valve, nor isita three waveband, nor does he If a straight set was designed using an S.G. as first stations-but when you get on the S.W.'s, especially pay 20 per cent duty or carriage, etc., from U.S.A. H.F., Pentagrid second H.F. and Det. and a Pentode from 46 to 50m., these signals are nearly always the They are really Yanks (they make their own valves, or Q.P.P. valve, this would be a vast improvement only means of identifying the variousstations. too).What are our radio manufacturers doing about on any normal three -valve straight and up to the Thus we get to my positively " stunning " idea the invasion which has only just started ? standard of supers-but still of the better quality (I hope).But seriously, there is an international Already one British firm is putting a £5 superhet of straights. committee for the allocation of wavelengths so why short-wave job on the market, built round American " S.11."replies with the greater selectivity of shouldn't there be an international committee for valves ! Supers.True, but is it not this which helps to snake the allocation of interval signals ?Better still, why Which, if any, British manufacturer will send me inferior quality ?Always an undesirable feature of doesn't the committee that controls wavelengths a box of cigars for the information that American any set. give each station its own interval signal, each station exports are well up on last year to this country ? In my experience I have found a well -designed being given a different signal ? Come on, fellow " Popular Wireless " men, give straight set to be quite satisfactory when provided This would make station identification simple. us some answers. with a good aerial.When Droitwich started my Of course, each station would have to be compelled Yours faithfully, straight four would separate it from Luxembourg to use its own signal and no other, but I don't think H. WILKINSON. without any modification to the circuit, which is this would present any difficulty as each station Plas Tara, 3, Nantygamar Rd., Craigydon, Llandudno. more than I can say for a large number of pre- would have a certain amount of latitude inits Droitwich supers when tested at a distance of 12 choice of a signal the same as it has in its choice miles from the station. of wavelength. Then again,I think most of the " A BONNIE OLDE BATTERY." The set employed band-pass with variable coupling stations would be only too glad to have a signal The Editor, POPULAR WIRELESS. to allow for improving the quality by decreasing the that couldn't be duplicated by others. Dear Sir,-As an assistant in a local radio store selectivity. If one doesn't think this scheme would be a the following amusing experience happened to me I consider aerials to be an important part of any success-at least from the listeners' point of view- a few seasons ago.One day the skipper of a set, although too frequently neglected.Most manu- Scottish drifter together with three of his crew, facturers recommend an aerial of about 45 ft.as came to the shop carrying a huge triple capacity being all that is necessary and as good as a longer one. 120 -volt H.T. battery (it must have weighed quite The set will probably be all right on this length, but a bit)plonked it down on the counter with the would surely be better with a 100 -ft. aerial. AN EKCO ALL -WAVER remark Can you test it, lad ? " Testing a well-known commercial set on my own I did and it was quite run down. When I told him, aerial (which is of the latter length and 35 ft. high), he complained, saying it was a dud, and should I was astonished at the poor selectivity although have run much longer, and he ended it all by saying, 9 kc. was specified and probably obtained with a short " And it's one of yours, we bought it from you." aerial. Enquiring when it was purchased he said, " The My experience shows that a small selective set start of last fishing," which was about fourteen working on a good aerial is as good as the average months previously.After explaining that he had high -power super on its usual short aerial.The had at least his money's worth from it, he reluctantly latter always using a few parts to bring in the signals purchased another similar battery which I handed and the rest to cut out the unwanted whistles, hisses, him, and lifting the old one from the counter I etc., which also come in. dumped ft in our refuse box. I shall always stick to straights, as they are in my " An' what be y'r gonna do with that," he asked. opinion the best.But let us hear what the Superites " Throw it away, of course, it's of no further use," have to say. I replied ;but he didn't or wouldn't believe what Yours truly, I said." Give it back here, lad, we'll take it back M. WILD. to the ship with us." So one of the crew had to carry the heavy battery about three-quarters of a mile up 121, Middleton Park Road, Middleton, Leeds, 10. the road to the ship because the skipper was afraid READ, MARK, LEARN there were a few volts left in his battery and that The Editor, " Popular Wireless." we would use it for some purpose. Dear Sir,-I am wondering how many of your Yours faithfully, readers have been passing their leisure hours during J. A. BOTWRIGHT. the past four weeks.Most of them are, no doubt, 79a, Nelson Rd., Gorlcston, Nr. Yarmouth. like myself, waiting patiently for delivery of their S.T. 800 kit.For myself, four of the longest weeks INVERTED " BREAK -THROUGH " I've ever known. I have read and re -read not once but a hundred The EditorPOPULAR WIRELESS. times or more, not only reports on the set but wiring Dear Sir,-I would be glad to know if any and operating data untilI know them almost by heart.For four solid weeks I've built the set wire of your readers experienced the following by wire in my mind's eye and followed them on the trouble with their receivers and would appre- blue print, and each time have gained useful knowledge, ciate a remedy through your columns. which will help when the great day arrives. Although the set has yet to be built, I have already When the set is tuned to any of the Regional entereditincompetition with oneofthelatest stations the Droitwich prOgramme comes in commercialall -wavesuperhets, and the two sets in the background, and could even be followed are going to be tried out side by side,station for ifthere was an interval at the Regional station, and I know which isgoing to come out on top. transmitters.High power foreign stations For years I've waited for Mr. Scott -Taggart to close to Regionals are not affected. bring out this set and as his previous designs have The receiver in question is a modern 4 -valve only been published after months of hard research work on his part I consider that the S.T. 800 is to be A.C. superhet,2 wavebands ;aerial about his real masterpiece, and the joy and pride of thou- 35 feet high, length 45 feet. Location :by sands of listeners.Having listened to several of the the south-east (Irish) coast, about 60 miles leading all -wave sets on the market I was beginning to doubt the entertainment value of short waves, This attractive instrument is the Ekco CTA 87. fromtheWelshcoast.Any information but now I am convinced that Mr. Scott -Taggart has an all -wave console costing 15 guineas. would be gratefully received. once again come to the rescue in his latest achieve- Cuaious, Popular Wireless, December 12th, 1936. 38t'.

ABOUT DETECTOR CIRCUITS By W. L. S.

JUST what started this particularitch letters opposite the pins of the coil -holder "A" with this condenser inserted en route ; forplayingaboutwithdetector are supposed to be against those pins as and as the whole coil is tuned, variations circuits I can't say.It has, however, seen from underneath. inthe capacityofthiscondenser will attained the dimensions of a pretty bad They do not represent the connections affect the tuning as well as the degree of " phobia," and readers clamour for more. to the valveholder in which the coil former oscillation. I suppose its popularity is partly due to is placed, but the pins of the latter (by The grid leak is in an unconventional the :fact that one can " re -hash " a detector which I mean the former) as seen when you position, and there is no grid condenser circuit over and over again with the same hold it up and look at the bottom.That at all ;but the circuit works beautifully, components.It doesn't cost anything- should be clear enough for anyone, so we as anyone who has used it on 5 metres until you put the H.T. across the L.T. will proceed. will confirm. terminals-and it doesn't mean a particularly Fig. 1 represents, in my opinion, about Reaction should preferably be controlled heavy lot of constructional work. the worst possible arrangementofthe by a variable resistance in series with the There is always the fascination of com- ordinaryreactioncircuit. I make no positive H.T. between the 'phones and paringtheresultsgiven bydifferent apology for reproducing it, however, be- the H.T.-- terminal.The same circuit arrangements.There is always the hope- cause, for some reason which I have never may also be rigged up with a screened -grid and what a hope-that you will suddenly fathomed, it is tremendously popular. valve asdetector,reaction then being It was oncecalled the Reinartz " controlled by varying the voltage on the A REACTION POINT circuit ;and backin1924the name screening electrode. " Reinartz," as applied to receivers, was mentioned with bated breath as if there Avoiding Hand -Capacity Effects were some association with black magic. Another very freely -oscillatingcircuit It works well (but no better than the is the ordinary Hartley, shown in Fig. 4 split -coilarrangement more commonly (on the next page).Both this and the one used nowadays), but it has a serious dis- just described suffer from the disadvantage advantage.- The reactioncondenseris that the tuning condenser is" live " on " live " at both sides.No matter which bothsides. Thismaybeovercome, way round you connect it, you will still however, by setting it back from the panel have hand -capacity effects when you go and using an extension coupling.There to grab the spindle. is an excuse for this in the basic form of Further, the H.T. is parallel -fed, which tlcircuit, whereas the reaction circuit of means that the " goodness " of the H.F. Fig. 1 can be so easily improved that there is no excuse for that position of the reaction condenser. WIRING TO PINS OSCILLATES FREELY Fig 1-The reaction condenser in this circuits Fig. 2-The " live " on both sides, a serious disadvantage in connections practice. tothecoil former pins looking at hit upon a circuit that gives those results the under- of which you have been dreaming for years. side ofthe In the days of the old two -pin plug-in coil base. coils this game was easy.Everyone used to chop his detector circuit about from time to time, and one heard of all the variations choke is a matter of considerable import- on a well-known theme.Nowadays the ance.Take this same circuit, use series popularity of the four -pin coil seems to have feed, and put the reaction condenser be- cramped people's style somewhat. tween the " dead " end of the reaction coil and earth, and you will have the much Circuits Not Often Used better arrangement that is regarded as the True, these four -pin -affairs seem to have orthodox detector circuit to -day. been made forthecommon -or -garden It has been illustrated so often that I grid -and -reaction circuit that we all fall don't even reproduce it on this page. back upon.But thereis no difficulty Fig. 3 shows a circuit that has made itself whatever in using them for other purposes. a reputation for being an easy oscillator. The main reason why new and inexperienced It is usually known as the " Split-Colpitts " Fig. 3-The " Split-Colpitts " circuit which oscil- readers don't do it is that they are not too arrangement, although the Americans call lates freely.It is a good short-wave circuit. sure of the connections, and probably they it the " Hoffman." have a positive horror ofthe smell of I have not shown any means of controlling Fig. 4 is a very straightforward arrange- burning rubber. reaction, because opinions differ strongly on ment. The two coils are combined to form This week I am showing three circuits this subject.One thing is certain-you one, and the junction between them comes which, for some reason, are not often used. can't do it by varying the fixed condenser at just about the right place for the tapping. Before we go further, please look at Fig. 2 between " B " and " C." The coil must be This circuitisseries -fed and works ex- and get it clearly into your head that the treated as a single one from " A "to tremely well. 390 Popular Wireless, December 12th, 1936.

ON THE SHORT WAVES-Page 2. set fhat seems to be " getting progressively worse."They don't get better, unfortun- ately !His worry is this :although he has logged stations like V K 2 M E, T I 4 N R H, OINTSk, 1/ C 0 C Q, H P 5 B and the rest of them, he can't log Australian amateurs or West Coast POST -BAG Americans. In any event the latter are pretty diffi- W.L.S. Replies to Correspondents cult to get hold of (except on 10 metres), unless one chooses the time carefully and is THERE does not seem to be much point in giving regular JD. (Belfast) reports good reception of used to deciphering weak stuff.I imagine, " station news " though, that his set needs a good clean out, these days, since so many readers .some of the U.S. police -cars and fixed have more time to keep watch on the stations, but I must correct him when new batteries, and possibly new valves, too. he says that they are working on 7 metres. C. R. G. also enquires whether two verifica- short-wave broadcast bands than I do tions from the same station, but concerned myself-and even they don't seem to hear They are mostly between 9 and 10 metres. anything startling !I suppose the truth At all events, his 7 -metre receiver does work with different wavelengths, will do for the -he hears the Alexandra Palace trans- V.A.C.I'm afraid they won't-it makes of the matter is that nothing connected things too easy. with short waves is startling now.The missions at R7-8 on it.Who said " quasi - arrival of a new station in South America optical ? " or Asia doesn't even cause the elevation of Several readers want to know if the little THE HARTLEY SCHEME an eyebrow-it's just one more on the list. - single -valve super -regenerative circuit can be used for broadcast reception.I should 5 -Metre Band Gets Going say not, myself, although I've not tried it. The fact of the matter is that short- Armstrongs and Flewellings were all very wave listening(except on the amateur well once upon a time, but in those days bands) is losing its old status.It is no Europe wasn't cram -full of powerful broad- longer one procession of thrills, as one new cast stations. station after another is logged ;it is more like a tour of the medium -wave broadcast Hard on the Neighbours band, except that its programme value is I imagine that the inselectivity of these usually somewhat greater. " supers " would put them right out of I hear that the 5 -metre band is " open " court nowadays. Anyhow, there's no harm at last. A British station has been received in trying, although it will be pretty hard on in Jugo-Slavia ;and C N 8 M Q, in French the neighbours if you don't use a stage of Morocco, has heard several of the Finnish H.F. in front ;and even then it would be amateurs. Look at the map of Europe for advisable to use a frame -aerial. this latter achievement, and you'll agree L. W. S. (Hendon) reports comparative that 5 metres is " going places' at last. failure with a short-wave circuit " culled Elsewhere on this page we have the news from many sources," and wonders whether Fig. 4-The Hartley circuit.As in Fig. 3 the that the Alexandra Palace transmissions tuning condenser is " live " on both sides, but this he is to blame for substituting indirectly - difficulty can be overcome by fitting an extension are being received in Belfast ;and I'll heated valvesfor the battery variety. rod so as to set the condenser well back from wager that before many weeks are past, Personally, 1 have always found the mains the panel. we shall have some more 5 -metre news that valvesfarbetterthantheothers-so really will make us sit up and take notice. L. W. S. can rest assured that this isn't A. E. R. (Swansea) is yet another reader his trouble.The fact that I don't often who takes a " B.C.L." Two to sea. He also Look Out for the " Yankee " showcircuitsofall-A.C.short -wavers uses medium- and long -wave coils with it, In November the yacht Yankee sailed doesn't imply that they're no good, but but doesn't find resultsup there " as good from Gloucester, Mass., on a cruise which simply that the vast majority of readers as they might be.Probably the aerial will last for eighteen months.She carries are interested chiefly in battery sets. coupling is not tight enough for the job. W8IGQ as her wireless operator, and Will P. K. (Irish Free State) and others Perhaps it would be improved by taking works on several " spot frequencies " on please note that cards for British amateurs the aerial, through a small condenser, to the short waves.She will be looking out can be sent c/o the R.S.G.B., 53, Victoria the top of the grid coil instead of to the for contacts on the amateur bands, and her Street, -London, S.W.1, if the full addresses third winding provided for the purpose. own frequencies at such times willbe of the stations are not known ? These cards 6,210, 8,280, 12,420 and 16,560 kc.The will then reach. them together with a batch Reaction for H.F. Stages call -sign is W C F T, and she is liable to be of others.They are sent out at regular A.E.B.(Tooting)has noticed the heard from several interesting points. intervals. tendency on the part of American designers Thecruisetakesinsuchplacesas " M. S. of Harlow," who used to be a to introduce regeneration into the H.F. GalapagosIs.,EasterIs.,PitcairnIs., regular contributor to these columns, wants stages, and wonders why we don't do more Samoa, New Hebrides, Papua, Bali and to get into touch with R. D. E. (Sawbridge- of it in this country. French Guiana.All amateurs hearing her worth). As Ihaven't the latter'sfull Generally speaking, the short-wave fans areaskedtoreportreceptiontothe address, perhaps he will write to M. S., that I know are more concerned with keep- A.R.R.L., West Hartford, Conn., U.S.A. who is Mr. B. M. R. Selby, Tye Cottage, Tye ing it out than with putting it in !I'm Another expedition to be looked for, this Green, Harlow, Essex. writing very soon about a two -stage pre - time in the amateur bands, is the 1936 selector unit, and we'll see what we can do Jarvis Island Expedition.The call -sign For 20 -Metre Amateurs Only about it in that. is K 6 G N W. Once more reception should G. L. (Bridlington) wants to make a set B. C. (Garstang) had heard " the New be reported to the A.R.R.L. for reception of 20 -metre amateurs and Zealand luxury liner " Z M B J, working In this case the transmissions will take nothing else. He remembered my statement with Rugby, G B C, but doesn't know how place in the amateur bands. that the commercial " 22 -47 -metre " coils to charm averi " from her. Perhaps D.C. It is opportune to mention here that would cover the 20 -metre band if tuned (Balham), who actually has one, will give many interestingstations, mostlycon- with a .000015 condenser. He has now for- me the address to which he sent his QSL nected with expeditions, rely on amateurs warded a circuit for criticism, and it seems card. for much of their communication.They to me to be O.K. A. G. (Rochdale) has a standard -base- often work outside the amateur bands, but Readers trying this should not be dis- board set which does everything but work, receive on these bands when they wish to appointed if the band required doesn't and he isinclined to suspect hiscoils, make contacts. " locate " itself quite properly.It may which are of a make that I have not men- Don't neglect, therefore, to listen outside cover 90°-180° on the condenser, or it may tioned hitherto.Looking at the leaflet, the 20- and 40 -metre bands occasionally. not come right in. A little wangling with however, I find that they use the same con- You may hear something of outstanding the turns of the grid coil, or with a parallel nections as those that I normally use.I interest-in which 'case I should be glad if condenser, should put things right. imagine that he has made a bloomer with you would let me know all about it. C. R. G. (Bury) has a standard -baseboard the connections. W. L. S. Popular Wireless, December 12th, 1936. 391 SEEN ON THE AIR PETO-S OTT News and views on the Television Programmes by BATTERY

our special radio -screen correspondent, S.T.800VERSION L. MARSLAND GANDER KIT "A"ca,: -;7.6 7'6 Complete Kit of Components exactly as FIRST DISASTER overshadows television as I There has also been some talk of danger specified and used by Mr. John Scott -Taggart, write.The fire which destroyed the from the high voltages used to actuate the with Konectakit (Gratis with Complete Kit) but Crystal Palace on theheightsof cathode-ray tube.Fears on this account lesswanderplugs,accumulatorconnectors, Sydenham was a tragedy for the Baird are needless.Receivers on installation are valves, Extractor Kit, Cabinet and Speaker. Television Company, which occupied the sealed at the back and must not be touched SouthTowerandadjoiningpremises by any but experienced engineers.I have KIT "B"Carriage Paio 14:14:0 As for Kit " A," but including set of 4 FIRST specified covering thousands of square feet. never heard anybody refuse to have a gas - valves only, less cabinet and speaker, etc. At the moment it is impossible to assess fireinstalled because people occasionally f f AstotKit " A, but with valves and the total extent of the damage, but report commit suicide in this way. KIT CT"Peto-Scott S.T.600 Table Cabinet only, states that a great deal of the Baird Com- loss speaker, etc.Carriage Paid R5/1116. Engineers do Not Worry pany's equipment was destroyed.This is KIT f fCC If As for Kit A," but with valves and But, apart from all this, a number of Pete -Scott Consolette Cabinet only, with indeed a blow to research.How serious speaker shelf.lessspeaker.eto. cannot be determined until the company television engineers have informed me that Caaglealltleatcl'.nst(31be0e.ry announce when and how they will resume from time to time they have shocks, which IIAs tor Kit " A." but with valves and KIT " CLL Peto-Scott ConsoletteCabinet, Type operations. are admittedly unpleasant but obviously " LL "onlywith speakerbaffle,lessspeaker. eto. not fatal.One man told me that the most CarriagePaid £811116. World's Largest Cathode-ray Tubes If Extractor Kitisrequiredwith anyofthe serious thing that happened to him was a above Kits. add £114/0 to Cash Price. The Baird Company had at the Palace sensation of paralysis in his hand, which theabovekitsarerequired complete with8 " wanderplugsand 2 accumulatorconnectorsas one of the finest, best -equipped and best - passed off in due course.Another offered, specified. ADD 1/9 to Cash Price situated centres for television research in for demonstration purposes, to put his hand the world.It was about three years ago on the point where he would receive a that the Baird Company first began its shock of some thousands of volts.I refused S.T.800 (Battery) experiments at the Palace, having con- his offer, and my advice to televiewers is : FINISHED INSTRUMENT structed a station there in record time. do not tamper with the inside with the DELIVERY FOR XMAS OR CASH REFUNDED The South Tower, 280 ft. high on ground current on ;the outside is as safe as houses CONSOLETTE MODEL Exact to specification. more than 300 ft. above sea level, gave the at all times. CompletewithFIRST SPECIFIED valves. Peto- wheel -shaped television aerial a command- I now have confirmation of the belief Scott Typo 101 matched speakerand walnut ing position.The tower, incidentally, still expressed last week that the staff at the consolettecabinetwith Australian walnu t stands. Alexandra Palaceisto be considerably veneered front and wings, Manufacture of the Baird cathode-ray increased in order to meet the universal dimensions 20 in.wide, 24 in. high, 12i in.deep tubes, including types claimed to be the demand for better programmes.After the (illustrated on left), less batteries. largest in the world, was carried on at the campaign of criticism of the last few weeks CASH r8 19: 6 Palace ;hundreds of new television sets some small improvements have been made PRICE CABINET ONLY, with were stored there at the time of the fire. in the programmes, but there is room for a speaker baMeboard, bat- tery shelf, and extension All the apparatus made for the B.B.C. great many more big ones. spindle, 35/-. television station at Alexandra Palace was Carr. & pkg. 216 extra. assembled and tested on the premises. The More Cabaret and Vaudeville extensive laboratories, which I have visited Some of the " interest " films have been A.C. MAINS S.T.800 many times, carried on research in every dropped and cabaret and vaudeville items branch of television, including big screen substituted. Programmearrangersare KIT'`A'' £9: 1 6: 6 Comprises complete kitofcomponents as development.There was complete trans- growing more enterprising. A realistic air FIRST SPECIFIED and used by Mr. J. Scott - Taggart. including Peto-Scott ready -drilled mitting plant and a set of studios and offices. raid, with a bomber flying overhead caught and polished walnut plywood panel, ready - Since the Alexandra Palace began broad- in the searchlight beams and anti-aircraft drilled terminal strips, aluminium brackets, casting I have been able to make a personal guns shooting, is to be staged by Terri- cabinet,mains lead, speakernuts and and Extractorbolts, Kit.lessvalves, test of three television receivers-the Baird, torials and the R.A.F. on December 12th. As for Kit As for Kit " A," Cossor, and G.E.C. sets.In view of the KIT"B"" A," but KIT "C"b u t including All this will be seen on the television screen, includingsetof3 valves and specified Peto-Scott circumstances surrounding the introduction by far the most difficult and ambitious specifiedvalves,less A.C.S.T.800Type" LL " cabinet and speaker. cabinet, with speaker baffle. of television-competition, secrecy, and the " outside " television feature yet attempted. Carriage Paid less speaker.Carriage Paid lack of facilities for manufacturers to test Other corning events are an amateur hour, £1111510. £1311216. on regular B.B.C. transmissions-the uni- an all -coloured cabaret, and cooking lessons NVII specified speakertype EMS £3 10 0 form efficiency of these commercial models, in the studio. FULL DETAILS AND ILLUSTRATIONS all ready for immediate delivery, is truly I think the man who infused most pep OFPETO-SCOTT S.T.800 STRUCTAK ITS, remarkable. into the television programmes during the CABINETS, ETC.,FREE ON REQUEST. week I have under review was Bill White, No Eye -strain from Television the American banjoist ;and the person Mr.J. Scott-Taggart's There are, of course, differences in the who made the best picture was one of the screen sizes and the number of controls. Ormonde Sisters, a brunette.A close-up Two of the sets, the Cossor and G.E.C., give of the latter was not only the best repro- TELE-SOUNDER a direct view of the picture on the end of duction of the week, but one of the most Cash or C.O.D. the cathode-ray tube ;the Baird shows a effectivetelevision pictures I have ever KIT "A"CarriagePaid reflected picture in a mirror on the underside seen. Complete kit of parts, as firstspeci- 38'6 Gentlemen may prefer blondes, but fiedby Mr.S.Scott -Taggart, and of a raised lid.But any one of these sets television needs brunettes. Van Dock, the shown in our advt. last week, includ- ing ready drilled aluminium screen, can pick up in the home first-class pictures cartoonist, was original and entertaining ; terminalstrip,readydrilledand polishedpanel,and twosidepieces, transmitted on eitherofthe Baird or so were the two New Yorkers.Television less valve. Marconi-E.M.Isystems from Alexandra must have items like these to arrest the Balance in8monthly payments Palace. interest of its passing audience.Bill White, of 4/6. By the way, a number of people have for example, galvanised an audience in my KIT" B' As for Kit " A," but including specified valve.Cash or C.O.D. Carriage Paid .£2;3/3, or 8 mentioned to me that they find television room. Duringotheritemsincessant monthly payments of 8/... tiring to the eyes.I, too, had this experi- chatter showed thatthemajority took ence at first, but I find that I have grown not the slightest interest in the programme PETO-SCOTT Co., Ltd., TI (lownti,City Road, Telephone: Clissold 9875. quite accustomed to televiewing and do not material, but only marvelled at the newest Wevt End: 62 (P.W.9), High Holborn, London, W.C.1. experience the slightest eye -strain. invention, EST. 1919. 392 Popular Wireless, December 12th, 1936.

RADIOTORIAL QUESTIONS AND ANSWERS By K. D. ROGERS HOW TO REMOVE PENTODE HARSHNESS F. U. S. (Surbiton).-I was interested in And on the behalf of " P.W." please accept TEMPERATURE OF A VACUUM your answer to S. C. C. F. in October 17th our thanks for helping a fellow reader out of G. S.(Nuneaton).-The boundless space issueabouttonecontrollingpentodes.I a jam. situated between the heavenly bodies is thought have a gramophone pick-up with pentode, and to be airless and intensely cold.If this is so, want to get rid of the harshness the valve seems EXTENSION SPEAKER ON PUSH- PULL am I right in assuming that the vacuum to impart to all music.What can I do?Is inside a valve is similar in temperature to it the speaker ? T. J. S.(Stoke-on-Trent).-My set is an that of space ? A.C.model with push-pull output valves. It might be the speaker, or it might be because Not really.A vacuum will allow radiant heat the valve and speaker are not properly matched. They are connected to a speaker with ter- to pass through it, but will not allow heat passage by Make quite sure by getting in touch with the makers minals marked P-H.T.-P.I want to fit an conduction.That is the principle of the vacuum of your speaker that the right ratio on. the input flask.But if anybody were to be put in a vacuum- transformer is being used. extension speaker, but how can this be done ? such as the anode and other electrodes of the valve- Apart from that, the best way to get rid of the Also, harshness is to fit a condenser and resistance in series if I want to use the ordinary speaker it would be found that they would take up the tem- across the input terminals on the speaker transformer. with a single output valve, can I do so ?The perature of the surrounding bodies by conduction The value of the condenser should be about '01, extension speaker is of the permanent magnet through the metal connections to them.They will and the resistance value should be about 1,500 ohms. also take up heat from anything like a fire that pro- A better plan is to use a variable resistance of, say, type. vides radiant heat, so you will find that there is no 25,000 ohms instead of a resistance. The extension speaker is easily fitted.Your best difference of temperature between the inside of the You could use a potentiometer, employing two of plan is to fit it to the secondary side of the speaker in valve and the outside. the terminals, viz. the one going to the slider and one the set.Just get one of those extension speakers You must not assume that a vacuum such as of those joined to the ends of the resistance element. (like the W.B.) with matching switching on it, and that of the valve is heatless. It contains a certain Join one terminal of the input transformer to one connect it to the secondary side of your speaker. proportion of gas, and that gas isof the same side of the '01 condenser.Connect the other ter- That is, connect the two terminals on the extension temperature as the air outside the vacuum. minal of the '01 condenser to the slider terminal of speaker to the two wires going from your speaker What happens in the case of spaceis thatit the potentiometer.Then connect one of the other transformer to the is assumed to be abso- potentiometer terminals to the remaining terminal speaker itself.Then the * * lutely devoid of gas or of the input transformer. switching on the exten- air. The gas and air are The tone is adjusted by varying the value of the sion speaker will enable The Editor cannot accept responsibility for manu- held comparatively close resistance. you to match it. scripts or photos. Every care will be taken to return to the various planets Regardingtheother MSS not accepted for publication.A stamped, and stars by gravity. In IT CAN'T BE DONE point, you can use your addressed envelope must be sent with every article. doing that they prevent existing speaker by using All Editorial communications should be addressed any sort of heat con- G. H. S.(Maltby).-I wonder if you could only half the primary of to the Editor, Popular Wireless,- Talfis House, duction away from the inform me how to amplify a gramophone pick- thetransformer. Just Tallis Street, London, E.C.4. heavenlybodies,and connect the output of the All inquiries concerning advertising rates,etc., that is; why " it is cold up without using a wireless set-that is by single -valveoutputto to be addressed to the Advertisement Offices, John up there." using a speaker and battery ? one of the P terminals, Carpenter House, John Carpenter Street, London, Radiant heat is pas- and the other to the H.T. E.C.4 sing through thevacuum I wish I could.I should make my fortune if I terminal. But you must The constructional articles which appear from of space from stars and knew how to do that.Sorry, but I am afraid that be sure that your output time to time inthis journal are the outcome of sun, but it has nothing you will have to use an amplifier incorporating valvewillmatchthe research and experimental work carried out with a which it can heat up valves, or else that almost pre -historic device known speaker if you do this. view to improving the technique of wireless reception. untilitreaches some as the microphone amplifier. It is best again to get in As much of the information given in the columns of gas or air surrounding This device was primarily brought into being for touch with the makers of this paper concerns the most recent developments the planets, and until the amplification of Morse signals in the days when the speaker. It is possible in the radio world, some of the arrangements and it reaches theplanets valves were few and far between, and it is not suitable that this method of con- specialties described may be the subjects of Letters themselves.In reality for music and speech amplification. necting will not result in Patent. and the amateur and the Trader would be there is very little heat- a good match, andit well advised to obtain permission of the patentees to ing of our atmosphere may be best to have an use the patents before doing so. which is directly carried MICROPHONE AMPLIFIER intermediate transformer out by the radiant heat betweenspeakera n d from thesun. Itis valve. Alternatively you done by conduction may be able to have the transformer on the speaker from the heat absorbed by the earth. And the rarer changed from one of the push-pull type to a straight the atmosphere the less the conduction and so the one. colder the air becomes. * TECHNICALITIES EXPLAINED-No. 32 PHASE DISTORTION A name that at first strilwi rather coldly on the mind, perhaps, but it is not nearly so formidable This sketch shows the principle of a microphone as it sounds.Phase distortion is merely the distortion of any radio or L.F. signal or impulse in amplifier working from a crystal set (see answer regard to time when compared with other frequencies. to G. H. S., Maltby). Look at the sketch.You will see that along It consisted of a scheme whereby the vibrations the top line I have drawn an L.F. impulse of from an earpiece diaphragm or similar device were certain frequency --say, 150 cycles.Under- impinged on to a microphone diaphragm.This neath I have drawn an L.F. impulse of much varied the current flowing through the microphone slower type-say, for the sake of illustration, and enabled another earpiece to be operated at 50 cycles.The light dotted lines are to assist greater strength than the first.Sometimes the one in comparing the right- and left-hand sections diaphragm was used for earpiece and microphone as of the diagram. shown in sketch. Now, these impulses start off together.The But it was a resonant affair and was prone to all beginning of each coincides in regard to time. sorts of distortion.1 show in the sketch a schematic The two have started out in phase with each diagram of the device. other.Look at the right-hand side of the To -day, the only sane way is to use a valve ampli- sketch.The ower impulse has lagged be- fier, which I presume Is what you refer to when hind.No longer does its peak correspond you say a " wireless set."I am sorry, but that, as with the first trough of the upper impulse. Martin Harvey used to say, is " the only way." It comes afterit.There has been phase distortion. The effect of that is not very noticeable in a receiver which deals only with sound, but it is notice- THANK YOU able in a television viewer.If a high note or high frequency L.F. impulse (say 10,000 cycles) starts Iprint here the letter I have received from from the transmitter in certain time relation (or in step ) with a low -frequency L.F. impulse (say 30 cycles) but arrives at the viewer out of step, there will be a flaw in the picture. Mr. W. H. Carter, of Hawkhurst, Kent, The phase distortion does not take place in the ether, it happens in the transmitter or receiver, thanking readers who have come to his assist- or both.That is why television receivers have to be so carefully designed.If the capacity and inductance values are not right there will be a tendency for the impulses of highest frequency to get ance in connection with an appeal recently through more easily than the low, and the result will be that the low -frequency impulses will lag far back copies of " P. W." containing blue- behind and cause phase distortion. There must be no question of " time lag " in the television amplifier.If there is, then the picture prints of the S.T.400 and S.T.500. will be distorted.If time lag were sufficient in a sound receiver for you to notice it the effect would He writes :" I am writing to let you know of the be (exaggerated, of course) that a violin might play a note at the same time as a double bass, at the numerous kind offers, also books and prints, sent to transmitting end.But on reception you would hear the violin note played slightly in advance of me by readers of ' P.W.'I have had offers from all the double bass, owing to phase distortion, or lagging of the lower note. over the British Isles.Would you please Insert in That is an exaggerated case, but it illustrates what does actually happen in every set, only you your paper my thanks to all for their kindness. cannot hear it because the lag is too small for the ear to notice.But the eye can spot it if time dif- There are too many letters for me to answer, Thank- ference exists in a television set, and that is why phase distortion must be avoided in television ing you and everyone most gratefully for the Service. viewers. " Yours faithfully, " W. H. CARTER." Popular Wireless, December 12th, 1936. 393

have been hearing is over ?Don't you find it rather an effort to drag yourself away from the fireside ? I do II find it much easier just to leave the set on until I have to move myself, and the net result McCARTHY is that these odd half-hours here and- there must 6 -VALVE ALL -WAVE RADIO make quite a difference to my running costs over a period. I suppose some people would callitlaziness. ON EASY TERMS Perhaps it is.But I am afraid that I regard it just WE CARRY STOCK of most of the McCARTHY as human nature.There is nothing like a warm Chassisand GUARANTEE PROMPT DELIVERY fire on a cold night for producing a condition of RF8AW. Completere- ceiver chassissupplied glorious inactivity, and I cannot bring myself to withall B.V,A. valves, think that I am anything but typical of my friends, knobs, leads, etc., ready the " P.W." listening fraternity, as a whole. Am I forfittinginyour right ? own cabinet (or suit- ablecabinetand But even allowing for the shortcomings of human speaker supplied if nature, there is no need really for this wanton waste, required)for only By G. T. KELSEY for there is a very simple and inexpensive solution £811010 complete, for all who own one of the W.B. 1937 " Stentorian " " W ANTED - 50 White Ants, and arecipefor speakers.Can this enterprising firm have sensed 27/-0WITH keeping them alive.Good prices paid." our shortcomings ?Personally, I shouldn't be at and 10 monthly all surprised knowing something of their traditions payments of RELIEVE itornot, that public S 0 S is the for being quick on the uptake. 161-. Li' seriousadvertisementofoneof Specification in brief perfectly The W.B. " Long Arm " unit, as it is appropriately 3 wavebands - long. Britain's leading radio manufacturers called, enables the user to switch his set on and off medium,short.Illuminated The Research Department of ouroldfriends dialwith principal station Messrs. E. K. Cole, Ltd., in common with almost and even to control the volume from the room in names. Automatic Volume Control. which he islistening.I think it's a grand idea, Tone Control. Switch for gram Outstand- all the other firms in this country who manufacture especially as the complete unit, providing itis ing per ormance on home and world stations equals sets for export, have for years been grappling with purchased at the same time as the speaker, costs average 8 -valve receiver. Write for 1937 Range the problem of producing instruments that are only15s.gd.But that's not the whole story. of McCarthy All -Wave Chassis from £8115/0. immunefrom" interference "inant -infested Supposing a listener's home is equipped with two tropical regions. or three extension speakers.If he switches the CASH or C.O.D. ORDERS Apparently these insects are particularly partial set on from one room, the speakers in the other to a repast of insulating materials, and when they rooms remain silent unless they are deliberately DELIVERY BY RETURN really get busy they are capable in a very short switched on from those rooms.Clever, isn't it ? time of eating sets right down to the bare wires, with, I have no doubt that many of you would like W.B. STENTORIAN SPEAKERS very naturally, dire consequences upon results. further detailsof this ingenious unit, and so I These splendid Speakers are avail- The quest for ant -proof materials has been going able on Easy Terms: 0/6 on for years, but progress Js slowed down very propose to make the descriptive booklet available 37S. CashorC.O.D.,42/-) under our postcard literature service.It is quite or 218 with order and DOWN considerably by the months required to send them free, and it contains details of the whole of the 11 monthly payments of 4/-. abroad for trial.So, with characteristic enterprise, W.B. 1937 range of speakers.Please quote the (PLEASE NOTE OUR EASY the research folk of Ekco are determined to combat reference number appearing at the end ofthis PAYMENT TERMS.) this menace " on their own ground," hence the 373. Cash or C.O.D., reasons for their present endeavours to obtain the paragraph when sending your postcard.(No. 37/10.) 3218, or 2/8 with order2 6 (All applications for catalogues reviewed in " The and11monthlypay- necessary white ants. Link Between" should be addressed to G. T. Kelsey, menus of 3/-. DOWN and Extension * * John Carpenter House, John Carpenter Street, London, SpeakersCabinet on similar terms. E.C.4, and the number given in black type at the end FULL LIST ON REQUEST. of the review should always be quoted.) ONE nn THE Estd. 1925THE NATIONALliig "TELE-SOUNDER" * LONDON RADIO SUPPLY PLAYER'S FOR Next week we shall publish a COMPANY full-size wiring print of CHRISTMAS OAT LANE NOBLE STREET LONDON E(

JOHN SCOTT-TAGGART'S GCAILY decorated Christmas packings are again a feature which the manufacturers of the famous Player's Navy Cut Cigar- "TELE-SOUNDER" ettes offer to smokers for the coming Christmas ARE YCIU EARNigiNGINEEINRS! -the wonderfulunit which makes Season. LES'S' THAN 110 PERWEEK? the television Printed with an appropriate greeting, these Ifso, you cannot afford to carry on without reading itpossibletohear our 268 -page Handbook.The book explains clearly packings containing 50, 100 or 150 Player's and definitely many ways of carving out a successful programmes on practically any set. Navy Cut Cigarettes supply the happiest of career. Among other things It explains the Services all solutions to the gift problem.They are of ouruniqueAppointments Department,outlines MechanicalHome -StudyCoursesElectrical,In all Motor,branches Aero,of Wire-Civil, available in tins of 150 for 7/3, 100 for 4/10, less,Television," Talkie " Eng., Building, I am assured that a life of luxury awaits the fifty 50 for 2/6, and in card boxes of 100 for 4/8 Govt. Employment, etc.,andgivesdetailsof white ants if, and when, they arrive, and they will A.N.I.A.E.. A.M.I.R.E,A.M.I.W.T.,G.P.O., have a menu of various insulating materials with and 50 for 2/5 ;having address space, they MATRIC., and all Exams. We alone occasional treats in the way of waxed cardboard or Guarantee-" No Pass-No Fee." can be dropped straight into the post with Whether you be an old hand or a rubberised tape recipient's name and budding apprenticegetthis book My friends at Southend tell me that this public just the addition of -1to-dav - FREE AND POST appealis alastresort.White ants have been address. -1 FREE. brought to this country by ship and 'plane-adult For smokers who prefer the ordinary 20's jBRITISH INSTITUTE .N0 ants, baby ants, and even ants in embryo-yet packets there arc postal cartons containing LOGY, 101, Shakespeare despite the fact that they have been provided with House, 17'19, Stratford Place, board -residence in specially -built " tropical " rooms, five packets of 20 for 4/91. London, W.I. none has survived to " do its stuff " under research Player's " Weights " in Christmas cartons department conditions. containing 4 packets of 15 for 2/-are an So if any of you happen to possess the much coveted secret of how to obtain, and to keep, white inexpensive, yet always welcome gift. ants in this country, here's a chance for you to become Player's " Gold Leaf " decorated tins of 50ELECTRADIX BARGAINS famous and to earn the gratitude not only of the for 2/11 are just right where a higher grade This BATTERY SUPER- Ekco Research ;Engineers but ultimately, wehope, SEDER provides H.T. from of our listening fraternity in the tropics. cigarette is required. yourL.T. 2 -volt battery, Player's Cork Tipped rectified andsmoothed. 3 In view of the generous prices that are being As for the ladies, tappings.A boontothose offered by Messrs. E. K. Cole, I am seriously thinking " Bachelor " Cigarettes, in flat tins of 50 for who are not on the mains. ofdiverting my own research activitiesto the 2/6, always make an acceptable gift.Then NewReduced and fromGuaranteed, £3 15s. production of white ants.Who knows, possibly there are those generous size Player's No. 3 37/6. with a bottle of peroxide and some common or RELAYS, CONTACTORS and CIRCUIT TRIPS garden " brunette " ants I might produce some"very Virginias in flat pocket tins of 50 for 3/4 lo:-each, H.T. TRANSFORMERS. -200/240-v. good " blonds."I shall then onlyi have to educate for smokers who appreciate a cigarette of to 10,000-v. 25 mia., 34/-, 5,000-v. 20 Tula., .19/6; them up to a proper appreciation of food values, 2,500-v. 15mia.17/6. Large" Butterfly "Neon and the money's as good as mine 1 extra quality. Signs, 4' 2^ X x 6., on glass panel, ready for Player'sWhiffs-thosedelightfullittle use, £7. COMPASSES. Boat Binnacle Mariners' 6" Boat Corn - W.B.'s Radio Robot cigars with the real Havana flavour-cost pass, floating, gimbal glasscase, 35/, Magnetic Com- 10d. for five, while a more ample smoke is pass liin., Brass Case, bevel glass, plain dial, unsealed, Those of you who follow my notes regularly will new, 9d. War Office Prismatic, 25f-. Travellers' pocket be aware of my enthusiasm for the extension speaker available in Player's, " La Doncella " Cigars 15/, idea, and because I have rubbed in upon so many which sell in packets of 5 for 2/6 or in boxes METERS. We large stocks of Meters, all ranges, occasions the great advantages of radio in every 50 micro amps, 40/Dix Mipanta, 19/6.Weston Table room I may perhaps be forgiven for assuming that of 25 and 50. Meters, 1816. Char ing Pole Testers, 2/8. 0-20 volts, most of you will have followed my advice. Nor has the pipe smoker been forgotten. 5/s.0-50 volts, 5/-, 0-100 volts, 616, 0-200 volts, 6/-, But there is a snag, and unless I am a very Navy Cut Tobacco inall A.C. or D.C. Repairs to all Well. exceptional sort of individual, I cannot help thinking Player's " Medium Write for New Bargain List "P." 100 Illus. Free. that most of you will have discovered it, too.When 1-1b.tins at 4/4 is always a favourite at you are enjoying a " nice lazy listen " In front of a Christmas time.Equally popularare "Air- ELECTRADIX RADIOS glowing fire and in a room remote from the one in man"Mixture in +-lb. tins 3/4, " No Name " which the set is installed, have you experienced that 218, Upper Thames Street, London, E.C.4. strong disinclination to go into the coldroom in in Ob. tins 5/-, and the "Digger " rangeof Telephone: central 4611, order to switch off when the programme that von all Empire Tobaccos at 2/8 per 1-1b. tin. 394 Popular Wireless, December 12th, 1936. * 1 Lidyoutheset was all right," Cried Dad-- why it's TECHNICAL JOTTINGS splendid to -night I - "RADIO Saidhisdaughter Items of interest to all Doreen, Courseit is,dear CONTACT" By Dr. J. H. T. Roberts, F.Inst.P. old bean, I'vefixed all the A constructor's magazine containing how- points with to -make details of four fine sets FLUXITE No Room in the Cabinet See that FLUXITE is always by you-in the house IF you are going to use Class B amplifica- -garage-workshop-wherever speedy soldering is needed.Used for 30 years in government works E have receivedforreview from tion it is obvious that you have got to and by leading engineers and manufacturers. Of Messrs. Graham Farish Ltd., a copy find room for the necessary additional Ironmongers-in tins, 4d., 8d., 1/4 and 2/8. of the latest edition of their popular components, and if the set is a very small, Ask to see the FLUXITE SMALL -SPACE SOLDER- compact one, say a portable, there may be a ING SET-compact but substantial-complete with magazine for constructors, " Radio Contact full instructions. 7/6. and. Television." difficulty because the cabinet is probably Write for Free Book on the art of " soft " just about as full as it can be already. soldering and ask for Leaflet onCASE- Included in the general editorial contents This is a point which has more than once HARDENING STEELandTEMPERING of " Radio Contact " No. 4 are full con- TOOLSwithFLUXITE. structional details,including wiring andbeen raised in letters from readers, and it circuit diagrams, of four fine receivers, for may be worth while to say something about Your wheels will NOT it now. TO CYCLISTS Ikeep round and true one of which a full-size blueprint is pre- unless the spokes are tied with fine wire sented with the issue. If there is no room for the extra com- at the crossings AND SOLDERED. This ponents inside the cabinet, the only thing makes a much stronger wheel. It's simple There is an attractive, well -designed two - to do is to use a separate unit which, of -with FLUXITE-but IMPORTANT. valve battery short-waver-the " Quest "course, will be external to the cabinet. Short -Wave Two-which can be built for Such a unit is sometimes called a Class B The FLUXITE GUN 47s. 6d. ; isalwaysready toput an easy -to -assemble design for " converter unit," and is very useful for Fluxiteon the soldering job all -wavereception-the" Internationalmaking a change over in this way. In fact, instantly.A little pressure Multi -Wave Three "-which works out at places the right quantity on a unit of this kind is so handy that it is therightspot,andone 57s. 6d., and a battery and an all -electric sometimes worth while using it even if you charging lasts for ages. (A.C.) version of that universally popular Price are not driven to do so by lack of room 1/6 Graham Farish design, the " Sensity Super." inside the cabinet. ALL MECHANICS WILL HAVE The parts for the battery version cost 50s., while the kit for the all -mains model works Unit out at £5 10s. Converter Let us assume that you are going to use Graham Farish are deserving of everya converter unit and you want to find a FLUXIT congratulation for the exceptionally clear suitable position for it.Generally the most and precise way in which the constructional convenient place will be at the back of the IT SIMPLIFIES ALL SOLDERING articles in " Radio Contact " are presented, FLUXITE, LTD., DEPT. 324, DRAGON WORKS, I cabinet where it will be out of sight, and BERMONDSEY STREET, s.E.1. and absolutely nothing is left to the con-then all you need to do is to remove the structor's imagination. With the aid of thelast valve of the receiver and put in the 2 WEEKS TO GO FOR XMAS.Still time to become a stage -by -stage wiring diagrams and theadaptor plug supplied with the unit, then step-by-step instructions, it would appear insert the valve in the socket which is PIANO PLAYER to be impossible for anybody to go wrong. EasilyeEnaa sflyt ntthe1)e " Radio Contact " No. 4 is a worthy provided in this adaptor plug.This is a of the party. CACl/11'6ONLY very simple arrangement and avoids any successor to theprevious editions, and interferencewiththewiring,the only thereislittle doubt that itwill enjoydifference now being that the loudspeaker widespreadpopularity.Itisavailable, is operated from the Class B converter unit. price one shilling, from dealers or direct The operation of this unit is very simple from Messrs. Graham Farish, Masons Hill, indeed, but if the set has, say, a couple of Bromley, Kent. stages of low -frequency amplification, you will generally find it better to plug the adaptor mentioned above into thefirst L.F. socket rather than into the second. SOVIET RADIO For connecting to the anode socket of the No previous knowledge required.Full instructions given, MORE than 410,000 new loudspeakers which can be easily followed. Satisfaction guaran- last valve which, of course, is ruled out by teed or money instantly returned. were connected up with the Soviet this arrangement, a wander -plug is provided. ORDER NOW. broadcasting system during the first M. & 0. SERVICES, LTD., (Dept. 40), 43, Woburn Place, London, W.C.1. nine months of 1936.The number of loud- speakers installed in the villages so far this Suitable Driver Valve year is 83,000.The most remote corners of A point which I should mention before RADIO the Union, such as the Nenets Autonomous going farther is that the valve used in ENGINEERING Area, the Buryat-Mongolian Republic, Yaku- thisfirstlow -frequency stage may not Home Study Course tia, etc., are now linked up with the broad- prove to be suitable for use as a driver valve THE BEST MEANS TO casting stations of the U.S.S.R. SECURE A RADIO CAREER for the converter unit, in which case it is WRITE for interesting FREE 11 -page booklet and start best to try the valve in the output stage, TODAY on the road that MUST lead to SUCCESS. TRANSPOLAR RADIO -TELEPHONE LINE putting this into the next -to -laststage, TheInstituteofPracticalEngineering, First Avenue House, London, W.C. Regularradio -telephonecommunications and see if it works any better. have been established between Krasnoyarsk, The grid bias applied to this valve is a Igarka and Dudinka.The first conversation pointofconsiderableimportance,and PLEASE BE SURE TO MENTION between Krasnoyarsk and Dudinka took place " POPULAR WIRELESS" WHEN on November 16th, and between Krasnoyarsk amongst other things it has a great influence COMMUNICATING WITH and Igarka on November 17th.Audibility on the high-tension current consumption. ADVERTISERS. THANKS! was said to be good. (Continued on next page.)

THE ONE AERIAL FORTHE MODERN SET 21 - Highly efficient,selfad- hesive aluminium strip- giveswonderfulpick-up clear of interference-fixed in a jiffy without tools-just PIX press it and it sticks. !Double 3 Length P I X I. ON DO ht,S E . I Popular Wireless, December 12th, 1936. 395

TECHNICAL. JOTTINGS are only being used as diodes, only the filament and one of the other two electrodes (Continued from previous page.) being used. ecuty TA -14 H.T. Mains Units With Class B. The Three -Electrode Detector Amplifies I would like to say something about the You can make a number of interesting BATTERY use of a high-tension mains unit in con- circuit experiments with a two -electrode nection with Class B amplification. As detector, and this has the advantage that VERSION you know, one of the objects, or at any the characteristic curve which it gives is S.T.800 rate one of the advantages, of Class B is to better than that of the ordinary three - economise current. If you are using a electrode valve although, as you know, it PILOT AUTHOR KITS mains unit this advantage isnot very does not amplify. I do not know whether I KITii11igee.1710:GcE. important unless, of course, there is already should mention that the ordinary three - PAID67/ such a drain on the H.T. unit that it is electrode valve as used in the conventional Complete Kit offirstspecifiedparts, being heavily overloaded. I will not pursue way as a detector amplifies to quite an with KONECTAKIT (Gratis),but this last point except to say that a mains appreciable extent.In the conditions in less wanderplugs,accumulatorcon- nectors,valves, ExtractorUnitKit, unit should not be operated in such cir- which the three -electrode valve is generally cabinet and speaker. cumstances, anyhow.If you are using a used in conventional circuits as a detector, Balance inII monthly payments mains unit in more or less correct con- it should not be regarded merely in the same of 6/3. ditions the saving on H.T. current with way as a two -electrode valve because, as I KIT f i IISi As for Kit'' A," but including 4 first specifiedvalvesonly,lesscabinet and Class B working will hardly make it worth say, it amplifies quite an appreciable amount speaker, etc., Cash or C.O.D. Carriage Paid £1/14/0, while to change over to this system from and this amplification is often taken into or 12 monthly payments of 8/6. KIT si CT ttAs Kit " A," but including valves and ordinary working. account by the designer in his calculations. Peto-Scott S.T.800 Table Cabinet only, less speaker,etc.,CashorC.O.D. CarriagePaid If the mains unit is able to supply plenty £5/1116, or 12 monthly payments of 10/3. of H.T. current, it may pay you just as well Stray Charge on the Anode di CP if KIT Pes tKSitc o"ttA S". Tb.8u0t0InCcludsinlg tveal Cabinet tostickto an ordinarystraightL.F. Those of you who want to try a three - only, with speaker baffle and battery shelf, less speaker, etc.' Cashor C.O.D. Carriage Paid £619/0, or 12 amplifier, with a good power valve output electrode valve connected to operate as a monthly payments of 11/9. stage, or to try the push-pull arrangement two -electrode detector can easily do so by " As Kit " A," but including valves KIT " CLL andPeto-ScottS.T.800Consolette which I described in these Jottings some using either the anode or the grid as anode Cabinet, Type " LL " only, with lift -up lid, and speaker baffle, less speaker, etc., Cash or C.O.D. Carriage Paid little time ago. of the two -electrode arrangement.If you .36/11/6, or 12 monthly payments of 12/-. are only going to use one of these it is per- 71 Extractor Xit Isrequired with any of the Two -Electrode Detectors wabove Kits, add £1/4/0 to Cash or C.O.D. prices, or haps better to use the grid, leaving the 2/3 to deposit and to each monthly payment. The questionoftwo -electrode valves anode " floating." 8 wander plugs and 2 accumulator connectors In this case the regular Ifare required with above Kits, add 1/9 to Cash or often comes up in my correspondence and anode of the valve is not used at all, the C.O.D. prices, or 119 to deposit. several readers have told me of the results grid serving the purpose of the anode of the which they get with these diode valves as two -electrode arrangement.You will see A.C. MAINS S.T.800 detectors.I should, however, say that in that a certain proportion of the electron most cases where the valves are described discharge from the filament will in such a KIT ftAif2ts,P,';:gm,19:16 : 6 as diodes they are really triodes, in other Comprises complete kitof components OR case pass through the grid and impart an as FIRST SPECIFIED and used by Mr. words, ordinary three -electrode valves, and J.Scott -Taggart,includingPeto-Scott electrostatic charge to the now insulated ready -drilled and polished walnut ply- 18' - anode proper ; wood panel,ready -drilled terminal this will increase in potential strips, aluminium brackets, mains lead, DOWN and tend presently to repel the oncoming nutsand bolts,lessvalves,cabinet,speakerand Extractor KiS. electron stream.To get over all this you And Balance in II monthly payments of 18/, can connect the grid and anode together, If valves required, add £1/18/6 to Cash or C.O.D. price Specified using them as a single electrode, in which or add 316 to deposit and each monthly payment. case you do away with this stray electri- for Mr. Scott-Taggart's fication and you will probably find it more N.T.S. SHORT WAVE 2 satisfactoryalthough,strictlyspeaking, 12-94 ei METRES a three -electrode valve connected in this ' Tele-Sounder ' way does not function quite the same as a real two -electrode valve having only a Mr.Scott - Taggart knows filament and anode and without a grid. Eriequality ! Screen -Grid Valve as Detector For the poten- While on the subject of detectors, if you Two -valve short-wave set of remarka ble range that will tiometer in the give you hoursofentertainment on the fascinating 'Tele-Sounder' wanttoexperimentin thisdirection, short-wave bands.Hit comprises all necessary com- you will find it interesting to try a screen - ponents, includingmetal -sprayed baseboard, three he specifies the variablecondensers,-0001,0002 and00016-mfd., grid valve for the detector.This can be on/oft switch, L.F. transformer, three baseboard mount- Erie Volume ing four -pinholders,short-waveH.F.choke,two Control. The usedquitesuccessfullywithordinary terminal mounts, four terminals, three fixedcondensers,slow-motiondrive, potentiom eter values of grid leak and condenser, but you grid leak, connecting wire, three 4 -pin that will not de- short-wavecoils,12/26,22/47,and must take certain precautions with regard 41/94 metres,2 component brackets, velop faults. to the anode circuit. and wiring diagram. Erie resistance Cash or C.O.D. Carriage Paid element plus With this arrangement, resistance L.F. 27/6, or 2/6 down and 11 monthly precisioncon- coupling is generally employed, and you payments of 2;6. 3'6 struction ensure must be very careful that the high-tension smooth contact voltage used is sufficient.As a rule, you N.T.S.S.W. ADAPTOR with built-in mains for years of use. will find it better to use all the available 12-94 METRES switch, 5/-. Hear America and all the World DIRECT on voltage for the H.T., then adjust the your present set, for only 17/6. Complete Kit voltage on the screen so as to get sensitivity of parts to build a reliable short-wave adaptor for use with any BATTERY receiver. and good quality. Hit comprises all parts for instant assembly, includ- ing metal -sprayed baseboard, 2 variable Choke coupling may be used instead of condensers, 00016, 0001-infil., 2 base- board mounting 4 -pinholders, short- resistance coupling, and has the advantage wave H.F. choke, grid leak, fixed con- that the loss of voltage in the choke is denser, adaptor plug terminal mount, two terminals,34 -pinplug-incoils, generally much lessthan thatinthe 12/26, 22/47, and 41/94 metres. 1 com- ponent bracket, slow-motion drive, trim- resistance.I need hardly say that with ming condenser,connecting wire and wiringdiagram. Builtinone EI choke coupling the inductance of the choke evening, will need to be sufficiently high. Cash or C.O.D. Carriage Paid 17/6, or 2/6 VOLUME CONTROL clown and 7 monthly payments of 216. Using Screens for Coils from all dealers. Screens of one kind or another are so New antesSalesCo THE RADIO RESISTOR Co. Ltd. very generally used nowadays that many 56 (P.W.17), LUDGATE HILL, LONDON, E.C.4. 1, Golden Square London, W.I. (Continued overleaf.) IMMEMEMIMIMEMIMMINEMIEST. 1924 396 Popular Wireless, December 12th, 1936.

TECHNICAL JOTTINGS 11^MISCELLANEOUS-siRECEIVERS, COMPONENTS AND (Continued from previous page.) ADVERTISEMENTS ACCESSORIES Surplus, Clearance, Second -Hand, &c. people do not recognise that a screen is not, (Continued) so to speak, all beer and skittles ;it has 3d. per Word 6d. per word for first words in heavy type RADIO BARGAINS. Amazingprices. Mullard to be paid for in a way which may not at 6,- per line for displayed lines M.B.3A, £4.10.0.6 v. Battery Supers, 86.All -wave first strike -you. The great use of screening, (12 pt. type) Superhets, table model, £6.15.0.Compacts,65/... Hundreds of bargains in Mains receivers.Ferguson incidentally,is what has made possible All- Wavers, £8.Speakers. Components. American, the compactness of modern receivers.If Minimum Charge 3'- English valve replacements. Stamp for list.Midland Remittance must accompany order. cheapest Factor. you are using screened coils, you should LITTLER,2, Barras Lane,COVENTRY. remember that the screen has a definite Advertisements for these columns are effect upon the characteristics of the coils, accepted up to first post WEDNESDAY WHENreplying to Advertisements, please be sure to MORNING for the following week's issue. mention " Popular Wireless."Thanks 1 and also upon their efficiency.You will The Proprietors have the right to refuse or appreciate this if you bear in mind that withdraw advertisements at their discretion. BANKRUPT BARGAINS. List free.Why wait ? Batteryall -wave setscomplete, 16-2,000metres, the screen acts by absorbing energy sent out Postal orders in payment for advertise- with three valves and M.G. speaker.H.F. pentode, from the coil in the form of what is some- ments should be made payable to the detector and pentode, in handsome walnut cabinets, times called the " stray field."Putting Amalgamated Press, Ltd., and crossed. .79/6. Ormond A.C./D.C. 3 v. with M.C. 59/6. Mullard All communications should be addressed 6 V. superhds A.C./D.C.,7 gns. Halcyon A.C.7 it in a somewhat loose but very popular to Advertisement Department, "Popular superhets, 7 gns.Many others.Also large stock Wireless," John Carpenter House, John valves, components.State requirements. Butlin, way, the screen" mops up " anything 6, Stanford Avenue, Brighton. which is straggling around. Carpenter Street, London, E.C.4. S.T. EIGHT HUNDRED.Guaranteed Specified Kit, 83.7.6.Extractor, £1.6.0.Specified Valves, 81.6.6. The Effect of the Shield RECEIVERS, COMPONENTS AND S.T. 700/800 Conversion Kit, 33/6. S.T.800 Coils, 2i/-. Lists free.Parko Radio, Terminus Road, Brighton. In doing so, however, it creates what is ACCESSORIES Exchanges, etc. scientifically called a gradientof energy Surplus, Clearance, Second -Hand, &c. potential, the screen acting as a " sink " S.T.800. Author'sKits,£3.7.6. A.G.Versions, SOUTHERN RADIO'SWireless Bargains ;all goods £8.0.0. Radio Goods. Lowest Prices. Part Exchanges. of energy. You have, therefore, to think of guaranteed and sent post paid. ServwellWirelessSupplies,64,PrestburyRoad, the " attenuation " of the energy surround- G.E.C.3 -valve London, E.7. ing the coil as being rendered much more BatterySets," Battery Compact Three," with 3 Osram valves, moving -coil speaker HEADPHONES. Brown, G.E.C., B.T.H.,Nesper, steep in consequence of the presence of the in beautiful bakelite cabinet, brand new, in sealed Sterling, Marconiphone, etc.From 2/6 pair.Postage shield than it would be if the shield were cartons, fully guaranteed ;50/. each (list85/10). 6d. List free. SPEAKERS.-CelestionSoundex permanent magnet, CRYSTAL SETS.Complete.Guaranteed. Burne- absent. The resultofallthis,which 10/- ; Telsenpermanentmagnet,with10 -ratio Jones, 5/6,Ditto, double circuit, 8/-.Large P.O. perhaps sounds very complicated to you. transformer to suit any receiver, 12/6 ;Telsen loud- type,10/-. Crystal detector, complete parts,1/.. speaker units, 2/6 ;all brand new and in sealed Sensitive permanent detector,1/6. PostRadio, is that the shield absorbs energy and thereby cartons. 183, Caledonian Road, London, N.t. reduces the efficiency of the coil (or what- COILS.-Telsen,iron core, W349, Midget size, 4/-; ever the component may be). Moreover, the Type W478 (twin), 9/- pair ;W477 (triple), 16/- set; BARGAINS ! BARGAINS !! BARGAINS !!! Type W476 (triple superhet selector and oscillator) SpecifiedS.T.700,£3 ;S.T.600,82-5-0 ;S.T.500, presence of the screen has the effect of 16/-set,all ganged coils complete on base with 81-15-0 ; S.T.300, 81-2-6.Lissen Skyscraper S.C. 3, reducing the inductance of the coil (this is switch ;Telsen I.F. transformer coils, W482, 5/- ; 51-5-0;LissenA.W.4,51-12-6. GrahamFarish Telsen dual range aerialcoils,withaerialseries Discoverer S.W. S,G.3,52-10-0; GrahamFarish really a consequence of the former), and so - condenser incorporated,W76, 4/-;Telsen aerial Multiwave3,82-5-0. Allbuiltand perfect with extra capacity has to be used in order to series condensers with shorting switch, 2/- ;Telsen valves. Prompt delivery. Send for full list of set and L. F.transformers, Type R.G.4(4 to 1),3/- ; all component bargains.-R. Wigfield, Edlington, tune to a given wavelength.Another con- brand new, in sealed cartons. Doncaster. sequence of the presence of the screen is MICROPHONES.-Ace(P.O.) microphones, complete that the high -frequency resistance of the with transformer, ready for use with any receiver, PLEASE BE SUREto mention " Popular Wireless"- 4/6 each ;Ace concert microphone, complete on when communicating with Advertisers. Thanks I coil is changed. chromium stand with volume control, ready for use with any receiver and amplifier, 11/-. MISCELLANEOUS Size of Coil Screen RESISTANCES.-Tru-ohm1 -watt, colour coded and In view of all this,itis obvious that marked, 36 assorted capacities on card ;6/- per card. WE BUYfor cash, all types of Modern Second-hand AMERICAN VALVES.-Afull range of valves for all RadioSets,Accessories,etc. UnbeatablePart - the position of the screen in relation to American receivers ;6/- each. exchange allowances for new goods.Bring, send, or the coil or other component is very im- HEADPHONES.-Lightweightheadphones,double write.University Radio Ltd., 82, Hampstead Road, portant and should be carefully chosen. pole type, 4,000 ohms, each ear piece ;3/- pair. Euston, London, N. W.1.'Phone :Euston 3810. REPAIGs.-Anytypeofreceivers. American, In the case of a coil, the screen cover British, etc., repaired by expert staff. SITUATIONS VACANT should not be too small, as otherwise it WEHavePurchasedtheComplete Component Stock of a Well-known Radio Dealer and Manu- will be in too close proximity to the coil facturer, and we are offering the complete stock in POST OFFICE ENGINEERING.Excellent openings and you will lose more in one direction parcel lots as under :- for males under 30.Start £3.13.0 weekly at age 17 5/-Parcel, containing components to the value of at and no experiencerequired. FREE detailsof than you gain in another.It may be least20/-,comprisingchokes,resistances,coils, vacancies, etc., from N.I.E. (Dept. 606), Staple Inn useful, before leaving the point, to mention switches, condensers, wire and circuits, 5/- per parcel. Buildings, High Holborn, W.C.t. 10/-Parcel, containing components to value of at that if the diameter of the coil screen is least 45/-, comprising variable condensers, screened G.P.O. ENGINEERING DEPT. (no experience about twice the diameter of the coil, this chokes, switches, resistances, screened coils,wire, required). Commencing 83.13.0 per week. Age 18-23. will generally be found to be a suitable circuits, etc., etc. ;10/- per parcel. Excellent prospects.Free details of Entrance Exam. ALLArticles Included in These Parcels are Brand from ratio. New and Modern. B.I.E.T.(Dept.568),17-19,Stratford PI ace, London, W.1 SOUTHERN RADIO.-Branchesat 271-275, High oixtzw-fliz-AmwgoigAguTiaprzAiliam-4. Reaction Gets the Blame Rd.,WillesdenGreen,N.W.10 ; 46,LisleSt., London, W.C.2.All mail orders to 323, Euston Rd., A set employing reaction, as most small London, N.W.t. ik sets do, is often liable to go into oscillation SOUTHERN RADIO,323,EustonRd.,London, CHRISTMAS N.W.1 (near Warren Street Tube).'Phone :Euston when the reaction is increased.As a rule, HOLIDAYS *, the reaction circuit gets the blame for all 3775. this, and, whilst in most cases it probably 3/-each-American valves,all popular types. 90 - ;1- Kindly note that alladvertise- day guarantee.Full range in stock, National Union, deserves it, there are some cases in which Hytron, Triad, Metal, Glass and M.G. Send for lists. ments for our December 26th the fault is not due to the reaction at all. 3/-each-Mullard, Cossor, Mazda, Marconi, Osram issue must be received by first v4 valvesforD.C.receivers ;allperfect. 90 -day Ps The trouble may, for example, be due to a guarantee.State type.Send Cash, or C.O.D. post TUESDAY, December 15th, screened -grid circuit not being properly RADIOGRAPHIC, LTD.,66, Osborne St., Glasgow, C.1 stabilised, so that it is this circuit which to ensure insertion. CONVERSION UNITSfor operating D.C.Receivers oscillates when the reaction is increased. from A.G. Mains, improved type, 120 watts output at kinleileo-PM4V5.°Z-n-7117.-M-V-V,V.V.VR A This again may be due to bad wiring or 82 : 10 : 0. Sendforour comprehensivelistof Speakers, Resistances and other components. 111,0PCSVCICNIOCII insufficient shielding of the high -frequency WARD,46,FarringdonStreet,London, E.C.4 parts, or again it may be traced to using Tele. :HOLborn 9703. Please be sure to mention incorrect voltage values. A THOUSAND BARGAINS On the question of the voltage values, MAINS TRANSFORMERS, M.C. SPEAKERS, MAINS "POPULAR WIRELESS° perhaps you will find that the voltage on VALVES, SHORT-WAVE GEAR, CABINETS, Etc. when communicatingwith the screen of the valve is too high, in which PREMIER SUPPLY STORES Advertisers. Thanks! case the obvious thing to do is to try using 90-22,HIGH STREET, CLAPHAM, S.W.4. a smaller value. SEND 3d. STAMP FOR CATALOGUE. 9. NORWAY`; BERGEN 352 9 SUNDSVALL L 1007 FINLANDHELSINKI 335 LENINGRAD /224 ENGLAND. FRANCE,NOON ABERDEEN 233 5 OSLO "7/SWEDEN MOTAL A ,389 0 ESTHONI4,,,TALLINN svc, 9 / 1*Est,Gk:NUM,ARLGERI nc 1>, NORTHERN IRELAND RE 307 SCOTTISHSCOTTISH NAT REG. 2657 391.1 GOT EBO RG sis a KULDIGA 211 1 ...."%. RIGA---.., 2,1.-. MADONA 514.6 , 0 MOSCOW 57: NEWCASTLE 261 a DENMARK KALUNDBORG,z,0 O ._...____..- ._.., LATVIA . NORTH REGNAT. 4.2128. 51,1 LITHUANIA? J KAUNAS 1961 ! DROITWICH. ENGLANDMIDLAND REG 296 2 HAMBURG..', KONIGSLIERF.2.9/ ( WEST NAT. 261 1 LONDON REG.34-: 42 BERLIN 334'7 i 1., N...... ' WEST REG. LONDON NAT HILVERSUM all 1175 '5,'_.2. .; POZ NAN \ 3731 ANTWER '''. ° HOLUM:V. . a 501 5 /*WARSAW /339 RUSSIA . a ESL A,1?.:,5 . "POPULAR ' PLYMOUTH -- 203 5 BOURNEMOU TH 2 u3 BRUSSELS COLOGNE /559 GERMANY *LEIPZIG 3,,a z N.* . ea GLEIWITZ z43, 01 ., .133.9 a3v.9 FRANKFURT 25, POLAND 39.98 WIRELESS PRAGUE 010M . I ! PENN ES -BRETAGt.E , ,...,.., 288.5 FECAMP 269 , LUXEMBOURG ,,i, ,,,,e, '.. NURNBERG .67. BRN0323,4;g1.4034AV5K A-OSTRAVA 0 , 411:---:.....,_KATO2W4,,,IC:r". LWOW , ROADCASTING POSTERADIO PARISPARISI /644 EN 3,4 /1 STRASBOURG- ... .._ `N :,..0 _N, '2' ' / 3+9-2 / STUTTGART ..,... r --, - - M'I-S-KOLC :OS:es .. EUROPEMAP OF PAR IS P.T.T.EIFFEL 13/.7 TOWER 206 BEROMONSTER 339-6, I .. MUNICH -6-0' ( '.-eC i.,,;A v IENNAy - v., ,BRATISLAVA .9!:.-S LOVAKIA BUDAPEST ISA 34.965.-' ' a 1st -5 LI MOGES3.3.5.2 ,,-.SWITz ERL -''.- 1 S077 ENS.Ff3-, ,.. , AND; '='- - t PO* BOLT.E,,,I,U X Lyons2159 , -- '---t - - '.!1.40NTE CENERI 297 / - -8 .AU STnake TRIESTE Z03-2: ' ,P,ECSHUNGARY r: 6,,....,_., R U MAN I A BRASOV 1875 j TURIN 263-2 TOULOUSE 328 6 MARSEILLES -/C)0:3- G0:01 AL:36 FRANCE .386 0 ,. .7. BUT: VlsEST SAN SEBASTIAN ...... "' BOLOGNA 245 4 BEIgp MONTPELLIER 224 NICE 2,3 2 FLORENCE 4918 YUGOSLAVIA ' LISBON 476.9 MADRID 274 410 4 BARCELONA 377,4 293 5 -'BULGARIA ANKARA 1961 SPAIN VALENCIA 352.9 ...... -- ROM E...o BARI 5433 AtoEINIZR 15" TURKEY (44 .2 p.m.7-'`''''- LITHUANIASWITZERLAND.AUSTRIA,NORWAY, 1kCZECHOSLOVAKIA.[.,SWEDEN.M YUGOSLAVIA, 'Y POLAND, PALERMO331 Ca FINLAND,ESTHONIM)4RUSSIA,TURKEY.LATVIA,PUMANIA, "Vj TE JHUNCARY. D 52y MOROCCO 1-11. ALGERIA ALGIERS SW* TUNIS 55, iv POPULAR WIRELESS December 12th, IL33.

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64 THE FULL -OF -THRILLS CARD CAME Popular Wireless, December19th, 1936. 397

Editor :G. V. Dowding Asst. Editors :A. Johnson Randall, A. S. Clark

RECORDING HEARING U.S.A. RADIO PARADISE DOCTOR RADIO I RADIO NOTES & NEWS A CONTRAST A B.B.C.- CAT

The Radio Marathon Belfast,on thefirstWednesdayeach their effect on the tissues in the treat- IS Germany going to beat the record so month.Slow Morse practice classes are ment of cancer. long held by Britain, and take the lead held there, and the club's new transmitter, Experiments now in progress point the in the number of licensed radio listeners G I 6 Y M will shortly be heard on the air. way to a solution of the questions of thera- in Europe ? Reports of reception from " P.W." readers peutic dosage, by which system encouraging For a long time she has been narrowing will be gratefully acknowledged.Full par- results have been obtained in the destruction our margin, and the latest German total - ticulars of winter programme from Frank of tumours in rats and mice. 7,757,265 on November 1st-suggests that A.Robb, 46, Victoria Avenue, Sydenham, she may reach the 8,000,000 mark before Belfast,N.I. A Contrast this country. IN contrast to the work of The latest British figure, for healingistheincreasing October 31st, was 7,853,131, STARS AT THE ZOO use of short-wave radio for and the Postmaster - General warlike purposes.My recent has stated that he hopes that reference toBritish methods the 8,000,000 mark willbe ofwirelesscontrolof aero- reached in 1937. planes prompts one reader to Germany hopes to hit that send me particulars of defence total this year ;but she may measuresinwhichwireless find that Britain's returning would be useful.Regrettable prosperity has exceeded pre- asitisthat ourthoughts sent expectations, and " got shouldbeturnedinsuch there first." directions,one cannothelp being struck by the manifold A Sound Society and important possibilities of ALL who are interested in radio in a national emergency. the recording of sound, In that connection I hear whether in the home or that thereisa proposalto professionally,willliketo increasethefeespaidby know that thereisatleast amateur radiotransmitters ; one live society catering for is this going - to encourage a their needs.Known as the community whoseskilland British Sound Recording equipment would rank high Association, this body meets among national assets in the onalternateThursdaysat event of emergency ? 44, Valley Road, Shortlands, Kent, at 8.30 p.m. Europe to Eye America ? A scheme of Associate WHEN speaking from his Membership has been arranged yacht, theElettra, Will Hay, the popular schoolmaster comedian, and Miss Lili Palmer, the Gains - whereby those living too far borough star, feeding the bears with milk at the London Zoo.Miss Palmer is to the President of the away to attend the fortnightly noted for her unusual influence over animals, especially bears, with the result that Radio Corporation of America, meetings may derivebenefit she is able to fondle them like pets. Marconi said recently," We from joining the Association. shall soon be able to see each All communications to the Hon. Sec., Doctor Radio otherby television."Sinceitiswell 7, Ernest Close, Beckenham, Kent. BECAUSE I believe itisa crimeto known thatthe great inventor weighs encourage false hopes I seldom refer his words to accord with the facts we Is This a Record in these Notes to the use ofultra - may expect tohear that long-distance HOW many active transmitters does the short -wave wireless for the treatment of regular television is not so impracticable average radio society include among disease. as has been supposed. its members ?I ask because I have Much work, however, is being done to A few days after the broadcast referred noticed that the Radio Society of Northern determine to what extent wireless healing to above there was a scare of fire on board Ireland, just over fifty strong, has no fewer can be used.The recently issued annual the Elettra.Fortunately, the outbreak than twelve transmitting operators, hold- reportoftheBritishEmpireCancer was soon under control, and did not reach ing call signs.Is this a record ? Campaign states that research has been the laboratory where so much wonderful The Society meets in the City of Belfast carried out on the biologicalactionof wireless work has been done. Y.M.C.A. radio clubroom, Wellington Place, short-wavewirelesswavestodiscover (Continued overleaf.)

NEXT WEEK: S.T.'s ARMCHAIR NOTES WILL APPEAR 3.3 ..... saMDoVIPS 393 Popular Wireless, December 19th, 1936.

AMATEUR MAKES TRANSMITTER FROM CRASHEDPLANE

What's That You Said ? Through Mr. Fahy I have received a B.B.C.'s New Scottish Official ISEE that the compilers of one of our letter from Mr. Sullivan in which he tells AMONG recent B.B.C. appointments the great dictionaries have been complain- me ofhisalmost incredibly good re- most interestingisat Edinburgh, ing because wireless has added 531 new ception. No wonder they say that New where a five -months -old cat has been words to the language.That, however, is Zealand is a radio paradise, when a chap given the job of Mice Controller. His only half the story. can sit in New Zealand and report to me, salary is ls. 3d. per Doubtless 531 new " At the time of writing (16/10/36) I can week, of which 9d. words have been hear quite easily-on the broadcast band--; goes on milk, 3d. on ' causing alotof Breslau and other Germans, all the main fish,and 3d.on trouble in the lexi- Italians, and many French stations.I will liver. cographers' offices, not trouble to enumerate them all ! " The hours are a butwirelesshas Believe it or not, Mr. Sullivan has picked bit arduous, but the done much more up and verified no fewer than sixty-four new official seems than add new words European broadcasting stations, on ordinary to be shaking down to the language. In -not short-wave-programmes, which is a very well, and has many a respectable world's record. already scored sev- home a faulty wireless set has caused one eral smart captures. or two of the very old-fashioned words to His superiors report that he is a very be brought out with such fervour that conscientious worker, who takes great pride mother has had to send the children to BROADCASTING BREVITIES in maintaining a smart personal appearance. bed ! With Percy Edgar, the Midland Regional Director, He is now engaged in sniff -testing every as compere, with stars from Birmingham pantomimes, corner and cranny of the building, and has Television's Growing Audience and three well-known broadcasting duos among the noted several attractive smells which he artists, and with Reginald Burston conducting the nobody knows exactly how Revue Orchestra, " Gala Variety " on December 22nd proposes to investigate further, as circum- promises to be an hour of excellent entertainment. stances permit. PROBABLYmany television receivers are in use in Barry Lupino and George Formby junior are two this country, but it seems certain that pantomime favourites who have already definitely The Leaders in Radio the makers of the sets are more than satisfied accepted. Itishoped also that June and Gene Gerrard will be among the guest artists. AT the beginning of this year the total with the present demand and indications. Clapham and Dwyer, Harley and Barker, and number of wireless receiving sets in The news that the B.B.C. has fitted two " Aerbut andGaertie "areeachtocontribute characteristic turns ;and therewillalso be two use all over the world was 56,000,000. sets in the House of Commons caused a bit speciallywrittensketches by Midland writers- Of these, 85 per cent are in the U.S.A. of a sensation,especially when it was tancis Durbridge and Edward Mason. As well as and Europe (excluding Russia). realised that this might have repercussions ther Revue Orchestra there will be a dance band. * * As compared with four years ago, this in many other debating chambers and Do listener?, prefer their dance music " sympathe- total sh6ws an increaseinthe world's public assemblies. tic," " swing,or " sweet ? They will be able to wireless audience of about 65 per cent. America, too, is sitting up and taking choose on December 22nd, when, in the Northern programme, three popular broadcasting orchestras are And which would you say are the four notice of the progress made in Britain, and to compete " for their favour.The first of these leading countries in wireless trade IFirst, aconsiderablepublicservicewillbe combinations, Tommy Matthews and his Concert the U.S.A., as might have been expected ; demanded in the .U.S.A. in the coining Orchestra (formerly the Revue Orchestra),isnot strictlyadance band, althoughitsprogrammes next,littleHolland, which isso bulb - year.This is all to the good, for it will invariably include symphonic arrang!ments of jazz, conscious that it just had to spread:itself on encourage development, which in turn will and these it plays with the accent onsympathy. Henry. Reed and his Orchestra present a genuine the valve and associated radio;;the third bring down the prices.And then, hard -up " swing "ensemble,ensemble, while Richard Valery and his country is Germany ;and tailing along comrades, you and I will get our look -in. Orchestra, which includes string instruments only, to the total exclusion of brass, plays music of the behind, with about one -tenth of the total " sweet " variety. trade, comes Britain. The Impatient 'U.S.A. Most of the British share of the trade is HAVING recently remarked that all you On Christmas Day Midland makes two contribu- represented by the transmitting side. have to do to get American stations tions to the National programme.- First, there is an hour's light music by the Coventry Hippodrome direct is to tune for one on ordinary Orchestra, conducted by William Pethers, in the early He Crashed-and Used the Wreckage wavelengths at any time from midnight till afternoon; and then in the evening there will be AWORTHING reader sends me some something characteristic of the region in the Music "milk -o," I thought Programme which Felix Felton has been arranging interesting details of the first wireless I could dismiss the to represent the music of the regions. set to communicate from Palestine You are listening to thisprogramme by subjectfrom my to Australia, America and other lands.It . the courtesy of.. . mind for a time.I was built by Mr. Rockall, now of Rustington was wrong, for the and formerly of the rascals have been World Record Beater an Invalid R.A.F. He was impatientlyarriv- AS a matter of fact, Mr. Sullivan holds stationedat Am- ing in Britain lona threeworldrecords,againstall man, near Jerusa- before the B.B.C. comers.(1) Most European stations lem, and his record - stations have closed verified on broadcast band, in New Zealand ; breaking transmit- down. (2) Most countries verified on the broadcast ter was mostly Twocorrespon- band ; and (3) The world's record for eleven made from old dents report receptionbefore11p.m., months' DX work, namely, 253 stationspetrol tins and the which staggers me because the European logged and verified,excludingall New parts of a plane in radio pack is then in full cry.I shall be Zealand and Australian because they are which he had very interested to hear from other readers too close to bother with ! crashed ! who can definitely identify an American Australian stations,1,000 miles or so Mr. Rockall had no components, so con- medium -wave station before midnight, for away, are ten -a -penny with Mr. Sullivan ; densers and all had to be made out of any cross -talking guy who can cross the he gets them in daylight ! scraps and grab -its,the only exception Atlantic and insinuate his talk into Europe's His letter bristles with station names and being the valve. An old Ford car was made nightly yowl deserves attention. so forth, but I must instead tell you of the to cough up much of the metal required, little personal note where he says how and finally Palestine's first amateur -made Radio Paradise much he appreciates " P.W.'s " interest, set got on the air, and called up the world. PARDON me amoment, lads, while I step because " being gassed at the war and con- What's more, no fewer than thirty-five aside to thank Mr. Pat Fahy of Fermoy fined to my bed a lot I can make the radio different countries answered the call, and for his courtesy in putting me in touch do what I am unable to do myself-keep in few of them suspected that they were with Digger Sullivan of New Zealand, the touch with the outside world."Hats off, talking to a lot of petrol cans and old world's champion DX-er. boys, and three cheers for Digger Sullivan. ignition parts ! ARIEL. Popular Wireless, December 19th, 1936. 399

BUILDING A 7 -METRE OSCILLATOR 'A valuable ultra -short-wave device, which acts both as wave - meter and miniature transmitter.It will enable you to find the correct dial settings for tuning in the Alexandra Palace, and also permit ultra -short-wave experiments in receiver design to be carried on when no suitable transmissions can be picked up

A paper scale is fixed to the panel for calibrationleak, and to a certain degree radiation. Consequentlytheradiation purposes. The pointer in this upon the H.T. voltage applied photograph indicates the position of the signal is unimportant. London Television sound wavelength. to the anode of the valve. The Such is the simplicity of the design that rate of charge and discharge verylittleneed be said regarding the WHEN experimentingwithtuning decides the modulation note. So much for construction. The warning has already been circuits on the ultra -short wave- the theoretical design of the oscillator. given that any deviation from the design lengths, it is impossible to calculate Now such an oscillator would be quitewill upset calibration more or less corn - with any degree of accuracy the wavelength uselessifitwere not atleast roughly which the circuit will cover. An extra long calibrated, and for this reason the par- MUST BE ACCURATE lead here, or a few more stray micro -micro - ticularpractical form of thisoscillator farads there,will have a comparatively has been chosen. Provided thatitis big effect on the wavelength. Consequently copied exactly,it should be possible to an oscillator of some kind which can be make a reproduction, the calibration of used, for checking the wavelength range is whichwillbesufficientlyneartothe very useful.Itis for this reason that original for the main purpose for which theoscillatordescribed here has been itis intended.That purpose is to have designed. available signals of the wavelength of the The necessityforsuch an oscillator television sound and vision transmissions wasfelt when experimenting with the at such times as these transmissions are receptionof thetelevision programmes not available. Itwillbeseen thatthe USES A " SQUEGGER " CIRCUIT wiring diagram is drawn in per- spective, thug showing clearly therelative.positions of the Lead component parts and connect- CoeG.. ing wires (the few that there are !). Itisessentialthat 0 0 0 0 4 these relative positions should not be altered,otherwise the 0 0 / 41Cce approximate calibration which aw-Oleizy is given will not hold good. These are the dimensions for the coil, which is Zaa2,6 made with No. 18 gauge tinned copper wire.It I should be borne in mind that the slightest varia- =s Portability Unnecessary tion from these dimensions may alter the wave- ooi Mid length coverage to a large extent. As the oscillator will be used for experimental purposes only, pletely, so do stick to the original arrange- it was decided that portabilityment as near as is possible.This is very Chrzs-scx was unnecessary, as it wouldeasy to do,as the components almost As in the case of the " Universal Oscillator " described in the always be used in the place " fall " into their correct positions quite November 28th issue of "P.W." a " squegger " circuitis used. used for such experimenting. automatically, owing to the fact that they The coupling loop is attached to the oscillator case and is shown in position in the photo on page 415.The pitch or note of the Consequentlytheneedfor fit between the points of the other com- oscillation can be varied by adjusting the H.T. specialbatteries to keep the ponents to which they are connected. size down was obviated. How- (Continued overleaf.) from the Alexandra Palace. The fact that ever, itis not advisable to use the same the transmissions were (and stillare) of batteries as are used for the receiver, as such a short duration limited the time that the coupling effect may be misleading. could be spent in circuit testing. Even although the whole oscillatoris screened,itis The Most Useful Form possibletore- Consequently the design of asimple ceive its signals " artificial transmitter " had to be con- ona. receiver sidered.It was decided that a modulated without a n y oscillator would be the most useful form. direct connec- With such oscillators it is unnecessary for tions, such are the receiving apparatus to be in an oscil- the peculiarities latingconditiontoreceivethesignal. ofthesevery Furthermore, the modulated oscillator is short wave- no more complicated than an unmodulated lengths. However,thescreeningdoes oscillator, when modulationisobtained diminish the radiation very greatly, and simply by the insertion of a resistance is certainly worth while.The signal re- and condenser in the grid circuit. ceived by the direct coupling, which is The oscillator is a real midget This isusually known as a squegger obtained by means of a screened lead con- job and no attempt should be circuit.The condenser charges and dis- nected to a coupling coil in the top of made to alter the layout. The f wo flexible leads are for H.T. chargesat arate dependent uponits the ,screenedcontainer,is,ofcourse, and LT. capacity and the resistance of the grid infinitelystrongerthantheincidental 400 Popular Wireless, December 19th, 1936. A 7 -METRE OSCILLATOR loopedforter- minal connections. (Continued from precious page.) The next job is solder the centre The most important point aboutthe tap wire to the whole thing is, -of course, the coil,The .middleturn, on 4" 4" dimensions of this are given in a separate the opposite side 6,",z2eczf/aee diagram. The 18 -gauge tinned copper wire from the ends, so that there are one THE COUPLING LOOP and a half turns I on either side of . 34 '

the tapping point. I That completes 1 I 2 1-; 1 the coil, and the '1' most critical part of the whole of Pca6e.x. the construction. .Occa.. '0'2944.46::, 2,V %laa I Pe"/,,,fray1 The Pointer + !tuft._ +e_ There are four other parts which /k4" i /4" Oaroat Lead. have to be made, and they are the ...r.c/teened panel, supporting 8" bracket,pointer, /47./zei &laze. and container. The panel,sup- Here are the dimensions you will need for drilling the paneland cutting the portingbracket, Paper scale. and pointer need'no comment.The fitting the other end of the bracket by means of of the pointer to the knob and the con- a / in. 6 B.A. screw and a 6 B.A. nut. struction of the container need some ex- To the other fixing hole of the valve holder planation, however. is fitted a soldering tag, which serves to The pointer is fitted to the underside of anchor the KT.+ flex lead.This tag is the knob by means of two 1 in. by 6 B.A. fitted by another 6 B.A. screw and nut. brass cheese -headed screws.The holes in Although it is possible to wire up without the knob should preferably be tapped, but soldering, it is advisable to solder if possible. ,70s,c.wee. of neztairse4 if they are drilled slightly under size it will Further comment on the construction of the ierogiawe .evorros..eve, be found that the screws will cut their own oscillatoritselfisunnecessary, asthe How the coupling loop is arranged on the inside thread and hold quite firmly.The relative diagrams give all other details. of the container.The end marked " front " is positions of these holes will be the same as that to which the panel is fixed. those given in the pointer. The Container for the Unit should be stretched to remove any kinks, Before proceeding with the construction Regarding the container, this is a wooden and three and a quarter turns are wound of the container, a few points on the wiring box covered with copper foil.The box consists of two pieces of in. plywood tightly on a former 1in.in diameter, and construction of the oscillator itself will with the turns touching. When released the be given, as this can be completed before 71 in. x 41 in. and two pieces 71 in. x 4 in. wire will spring out to a certainextent the container is made.The supporting These pieces are for the top and bottom and the diameter of the coil will increase bracket and panel are clamped together by and the two sides respectively.The end to, approximately, I/ in. and the number means of the tuning condenser bush and piece is also of plywood, but only 1 in. of turns reduce to just about three. fixing nut.The valve holder is fitted to (Please turn to page 415.) The ends of the wire are bent up so that there are exactly three complete turns. YOUR GUIDE TO THE WIRING It may be necessary to " shape " the coil so that the diameter is correct.This can

COMPONENTS FOR 7 -METRE OSCILLATOR 1 B.T.S. micro -condenser, type M.C. 1 Dubilier 101-mfd. fixed condenser, type 670 I T.C.C. 101-mfd. tubular fixed condenser, type 250. 1 Clix chassis -mounting S.W. 4 -pin valve holder, with screw terminals. 1 Erie 1-meg. i-watt resistance. 1 Piece 18 -gauge aluminium, 8 in. X 6 in. 18 -gauge tinned copper wire for coil and wiring (about 4 ft.). 16 -gauge aluminiumforbracketand Pointer Wood for container (see text). Copper foil (see text). Screws, ilex, etc. 2 Belling & Lee wander plugs. 2 Belling & Lee accumulator spades. VALVE Marconi or Osram, L.21. BATTERIES See teat * * be done with the fingers, and is quite easy. The spacing must now be adjusted by stretching the coil so that the turns are 5/32 in. apart.The ends are now cut to The wiring is simple, but the form of layout shown should be carefully adhered to.Details of the bracket the lengths indicated in the diagram and will be found on page 415. Popular Wireless, December 19th, 1936. 401

SOME HINTS FOR THOSEON THE MAINS If you use the mains, especially A.C. supply, for your radio, you will find the various ideas des- cribed on this page of interest 180 -voltsecondary similarlyconsistsof " UNIVERSAL," A.C.andD.C.re- and value ceivers present one or two unusual 180 x 8 = 1,440 turns ;or, if we require features which it will be useful to By HANDEL REES a 4 -volt heater winding, we must put on note when doing adjustments to this type 4 x 8 = 32 turns-actually, one or two of set. extra turns would be put on to compensate for voltage drop in the transformer. Any universal set must essentially be a reads 2.5 volts across a testcoil of 20 D.C. one.An A.C. receiver is generally Provided discrimination is used in the turns, the transformer isdesigned with choice of a safe primary voltage, the method fitted with a transformer, and without 20/2.5 = 8 Turns/Volt. switchingor some means of changing can be applied to find the turns on any connections it is evident that the primary transformer.The meter must be fairly side cannot be connected to a D.C. supply. A SIMPLE SCHEME accurate, but a good moving -iron instru- We find, therefore, that the universal ment calibrated on A.C. will do. receiver is usually coupled directly to the supply without a transformer, the same as "Inverted" Transformers an ordinary D.C. receiver.Valve heaters Itis sometimes asked whether a mains are also connected in series across the supply transformercanbeoperated" upside- through a suitable dropping resistance, or down "-i.e. use, say, an L.T. secondary as barreter lamp. primary.Thus, if a 4 -volt secondary is This evidently brings us back to a D.C. coupled to another secondary supplying arrangement where the usual precautions 4 volts, as in Fig. 1, what voltage may be against earthing the supply, etc., must be obtained off the mains primary of the first carefully observed.It must not be for- transformer ? gotten that one of the A.C. mains is earthed Now, since the step-up, or step-down, exactly the same as D.C., except that there ratio of a transformer is constant, the answer How a step-uptransformerisconnectedto isthat we would get a number ofH.T. is no question of polarity. the L.T. winding of an ordinary mains trans- On D.C. the rectifier simply acts as a former. voltages across the various primary taps resistance in the H.T. circuit.As current closely approximating the mains voltages will only pass when the rectifier anode is Knowing this, it is easy to find the turns for which they are marked-e.g. 200 v., positive with respect to cathode, the mains on any winding.For example, a 250 -volt 230 v., and 250 v. must be connected the right way round. primary has 250 x 8 = 2,000 turns ;a The method can be useful for a separate With A.C., however, the direction H.T. supply, if an L.T. source for of being fixed, revers- the new primary is available.Of ing the mains plug will not prevent course, it is a roundabout method the set working. BROADCASTING IN FRANCE which gives rather poor voltage regulation, owing to the several TestingTransformer Turns impedances in the circuit.It is Is there an easy method of interesting to note, though, that finding the turns on a transformer the primary L.T. current will now winding ? be in amperes, the current being This question sometimes ininverseproportiontothe presents itself when it is desired voltage. to modify a transformer in some "High Potential" Windings way.Thus, where space is avail- A point which isapt to be able, an extra heater winding can overlookedinregardtoL.T. often be added if it is certain the heater windings is, that they can prithary will carry the extra load. be at two different potentials at Of course,itisnotvery the same time. difficult to find the turns required The statement refers to valve on such a winding by trial and rectifierwindings.Theheater error, but if the " Turns/Volt " winding provides, first, the 4 volts factorisrequiredforanother or so for the filament, but itis purpose, it can be determined in alsothepositiveof theH.T. a few minutes with an accurate supply, being atthe full H.T. A.C. voltmeter. potential with respect to earth. Finding the "Turns per Volt" The importance of this fact lies not onlyin the possibilityof All that is necessary is to put shocks but also in the necessity on a temporary " testcoil " of for well -insulated L.T. windings about 10 turns and measure the whentheyareintendedfor A.C. voltage across its ends with rectifiers.Many transformer the primary switched on.The breakdowns to earth can be traced size of wire used is quite unim- to a rectifier heater winding in- portant, and should the meter sufficiently insulated from core, or not be very sensitive, a further adjacent L.T. windings which are 10 turns may be added to give themselves earthed at an external a good reading. point. Dividing the known turns on the While on the subject of mains test coil by the voltmeter reading, transformers, a few words about we get the Turns per Volt figure, the method of varying the second- which is a constant for both primary The reception -hallat the French station at Cote d'Azur.The modernistic design of this entrance -ballis typical of the present aryvoltagesbymovingthe and secondary of a given trans- trend of broadcasting -station architecture. primary tappings may be useful, former.Thus, if the voltmeter (Please turn to page 420.) Cee,eiczZ C000.5-7Wfte Coe -4/5/9.4_ Vcrioreefa-ecz'. 08.- I. ChokeflE N.7* Full-size wiring print of John Scott-Taggart's " Tele-Sounder "-the wonderful unit with which the television programmes can be heard on practically any set. concerning the " Tele-Sounder " appeared in the two preceding issues of " Popular Wireless." Jr>Lee,Z. Constructional articles Popular Wireless, December 19th, 1935. 403 TELEVISION TOPICS_Collected by A. S, Clark

NOT SO BLACK Keith Prowse & Co. Ltd., 159, New Bond Thosewhohave Street, W.1. A weekly feature which will keep the reader au fait studied the technique They also inform us that " Teleceivers " with all the latest news and developments in television of modern television are on demonstration from time to time at the following stores : science.It will appeal alike to the newcomer to transmission may be surprised tolearn Bon Marche at Brixton. television and the advanced experimenter that in spite of the Holdrons of Peckham. modulation during . John Barnes of Hampstead. theframefly -back Trewins of Watford. being " blacker than black " itis possible Jones Bros. of Holloway. for this fly -back to be visible. Pratts of Streatham. " TELEFRAMES " The reason for this is to be found in the Quin & Axtens of Brixton. Items of general interest time -base. What is often happening is that Finally,demonstrationscanalsobe the fly -back is not coinciding properly with given at their London office at Africa House, the cut off of modulation on the tube. Ad- where a special room has been set aside for THE PerformingRightSociety,to justment in value of the charging condenser this purpose. whom thefeeforpermissionto and resistance will usually put matters right. We understand as well that the Marconi - reproduce radio programmes in public phone television demonstration salon at places has to be paid, are requiring a STAGE AND FILM EXPERIENCE Radio House, Tottenham CourtRoad, further fee for similar public demonstrations It is interesting to note that Mr. Leslie London, W.1, which has seating accommo- of television programmes. Mitchell,thetelevisionannouncer, had dation for 30 people and employs three This is a great pity so early in the both stage and film experience before he television receivers, is open to the public. development of television.Where a fee is alreadypaidforthereproductionof A CATHODE-RAY TUBE TESTER ordinary sound programmes, there should surely be no need for further payment A because an artist is seen singing a copyright song.In any case, there appears to be no G.E.C. reason why the matter should not have been left in abeyance until television is SET a little more firmly established. ON " ONE MAN'S MEAT-" TEST We hopethoseresponsibleforthe television programmes are not letting the The G.E.C.re- interestingnatureof thetechnicalities ceiver which I have run away with them. And in the following recentlyhadin- remarks the greatshortageof money for s ta !led fortest television programmeshasnotbeen purposes at my forgotten. homeinBarnes, The interest of television to the con- aboutninemiles structor,experimenter and technically - f r o m Alexandra minded at the present is almost entirely in Palace, shows a thewonderfulnatureofitstechnical picture 9ins. by So long as something is 7 ins. directlyon accomplishment. A close-up view of the Ediswan cathode-ray tube tester to which reference was transmitted to enable experimental work made last week. the end of the tube to proceed they are satisfied. and at an extremely But not so the looker who is interested joined the B.B.C.The ten years he spent convenient height.The set works best on simply because of what he sees and does in this way and the year as an announcer its own aerial, a di -pole consisting of two not care a hang about the romantic nature at Broadcasting House have undoubtedly short lengths of copper tubing.These are of how he sees it.To these the present stood him in great stead in his present supported on a wooden framework which programmes, with their constant exhibition task of launching an entirely new technique. has a short arm jutting out in the centre to and educational flavour,are not good. carry a co -axial lead-in away from the News actuality can make television the aerial at the best angle.The total length biggest thing in the country-without it, of the aerial is about ten feet-half the its appeal is lost. WHERE TO SEE wavelength. At first glance the receiver appears to * TELEVISION have as few controls as an ordinary sound receiver-only four.This is a remarkable Christmas Week MESSRS. Pye Radio Ltd., inform us achievement at such an early stage of tele- at "A.P." that their " Teleceivers " are actually vision reception, though closer acquaint- The first television Christmas will be appro- installed at the following addresses, ance reveals that two of the knobs are of priately observed at Alexandra Palace.Through- and that the firms concerned will be only the two -in -onevariety and the master out the week December 21st to 26th the television programmes will have a Christmas flavour, with too happy to welcome any tele-viewers who switch has three positions-" off," Baird, many items of special interest to children. Harry may be interested. and. Marconi-E.M.I.Tuning is by sound, Hemsley, famous child mimic, comes tothe and as the condenser has been locked into studio on Monday, December 21st, both after- The Teleradio Co.,497,HighRoad, noon and evening, withhis children and Bruce Grove, N. position it can only be turned in a short other young visitors, to see a display of all the arc. There are four subsidiary controls new toys.These will include a scale model of A. Imhof Ltd., Imhof House, New Oxford Gatwick Aerodrome, model trains, the latest in Street, W.C.I. and. a " brightness " knob under a panel at talking dollsand such novelties as a wireless - the side.These four controls can, if neces- equipped toy car and an electric -car race track. J. B. Cramer & Co. Ltd., 46, Moorgate, sary, be manipulated with a screwdriver. A unique parade of live animals to be E.C.2. televised on December 22nd will include Claude The receiver costs 95 guineas. Zola'shorse, Mary the ape, Gilmore's white EricRivers -Smith,Ltd.,21, Heath I have found the set extremely simple to poodle, Tarzan the human ape, and Joe Arthur Street, Hampstead. and his goose.It should perhaps be explained operate.The pictures are admirable, in that all these animals are of the synthetic variety. John Barker & Co. Ltd., Kensington black and white with a faintly greenish tinge High Street, W.8. which is restful to the eye, L. M. G. 404 Popular Wireless, December 19th, 193ff.

probably simply be breaking up the frame into some sort of pattern.But as we increase TELEVISION TOPICS-Continued the number of lilies the pattern changes into a number of horizontal black lines. " black."The size of the frame will thus, As line -speed is increased it will be noted WHAT IS THE SPEED? in effect, be halved as soon as the scanning that these lines quickly turn round into a is at the same speed as the frequency of vertical position, and then turn over, as it the pulses applied to the grid or screen. were, and become horizontal again.These WHEN testing out a double time -base A suitable source of supply for the sine - vertical black lines will occur at intervals as for television, or when experiment- wave modulations isa set of constant - the speed is increased, but there will be fewer ingwithdifferent circuitsfor frequency records. With these it is possible of them each time. scanning, one of the biggest difficulties is to to work up step by step from some lowish get some idea of the speed at which the line frequency at which the effect can be most Modulation Frequency Factor side is scanning.The frame, or low speed easily picked out. When they occur,itmeans that the time -base,doesnotpresentthe same In practice one meets a number of effects number of linesissome factor of the difficulty. with this scheme which justify description. modulation frequency.With the latter at The following is an idea which I recently Assume the application of, say, our 1,000 - 1,000 we should get four vertical bands at worked out and which I havealready cycle note to the grid, and that we start 250 lines because there would be four modu- provedinpractice up to about 6,000 with the line scanning far too slow.It will lation cycles per line. deflectionspersecond - the At 500lineswe get two number of linesin the Baird vertical black lines and then system oftransmissions. It at 1,000 cycles one black line opens upinterestingexperi- or half the picture black, as mental possibilitiesfor those already described.The sudden who have a cathode-ray tube lifting of the horizontal lines and its associated apparatus. to vertical and then their going back tohorizontal again in Taking an Example theoppositedirectiongives The scheme is best explained warning of11e approach of by taking a particular instance. the desired speed. Suppose the line scanning is Asthereisno synchron- drawing exactly 1,000 lines per isation being applied to the tube second, and that we apply a it is not easy to hold the half sine waveofexactly 1,000 black and half white position. cycles per second to the grid Also due to lack of synchron- of the tube, in other words isation and because of varia- modulate the beam. tions in the scanning circuit or While one line is taking place valves, the black vertical line the grid will be made, say, more may become curved.In such negative for one half and less cases part of it will occur on negative the second. And as- the opposite of the frame, and sumingthevoltages on the " walnut veneer " patterns may tube are properly adjusted to result.This could be over- provide rectification,this will come by suitably applying a result in half the line being A happy, informal snap which wellillustrates, withtheaid of a Cossor bit of the modulation cycle to brightand half the line becoming television receiver, the attractions of " television for two " in the home. act as sine input. A. S. C. * full amplitude of the carrier, and ticethatpartofthecarrier black parts to about 40 per cent. amplitude between 40 per cent. TELEVISION FOR BEGINNERS of maximum value. and zero is used for the transmis- The transmission system is so sion of the synchronising impulse, Q. Stevens describes the nature designed that a definite degree of as explained before.It is easy to of the television signal this week brightnessisassociated with a keep the synchronising impulses definite amplitude of carrier wave, separate from the picture because and thus a bright scene means that of this limit which is imposed on HAVING settled the circuit for proportional to the grid voltagethe average value of carrieris theamplitudeofthecarrier. producing the scanning lines applied to the tube. higher than thatfor a normal Thus : the next thing is the pro- This property of the tube is very scene. When themodulated Amplitudes between 40 per cent. duction of the picture. We have important because it enables us tocarrier wave isapplied through and 100 per cent. of maximum already seen that the television produce morerealisticpicturesthe receiver to the tube the grid = picture signal. signal radiated is made up of two than were formerly possible underreceives a bias proportional to the Amplitudes below 40 per cent. portions-the signal proper and the old definition.The reason isaverage value of the carrier wave, -= synchronising. the synchronising signal which is this.Suppose an outdoor sceneand hence the brighter the scene And if the circuit is arranged cor- sent at the end of each line and is being televised in brighCsun-the less the grid bias and the rectly they can never be muddled each picture.For the time being light.To givethiseffectthebrighter the screen appears. up. we can consider the true picture screen should be brightly illumin- You will have noted that the signal which produces the varia- ated, while if the scene takes placecarrier amplitude is 40 per cent, of A Point to Note tions in the screen brightness as it in a shady room the brightness ofthe maximum for the black parts We might remember that the is scanned. the picture should be reduced toof the picture.So far as the tube complete signal corresponding to suit. is concerned we adjust the bias on each line scanned is made up of Tube " Characteristic " This means that quite apartthe grid so that the line is blacked modulating signal plus synchronis- This is applied to the grid of the from the ordinary modulation inout at this value of incoming wave. ing signal, and the latter is ob- tube and cuts the beam off or brightness caused by the natureNow if you look back at the notes tained by lopping off a bit of the increases the current in the same of the scene, there must be anon synchronising you will see that time which should be devoted to way as the audio frequency signal overall variation in brightness ofat the end of each line scanned the the scanning line. applied to a valve alters the anode the screen to correspond with thecarrier wave drops down to zero. This time actually takes 10 per current.In fact,the " charac- subject.The overall variation is cent. of the time of one line, so the teristic " of the tube is almost the produced by a form of " auto-"Blacker than Black " completecycleofsignal is : same as that of a valve, except matic brightness control " (A.B.C. This means that if 40 per cent. Signal 9/60,000ths sec. synchronis- that we deal with screen bright- instead of A.V.C. !) which is sup-amplitude corresponds to black, ing pulse 1/60,000th sec., making ness instead of anode current in plied by the carrier wave in thethen 0 amplitude must be " blacker 1/6,000th sec. forthe complete the circuit.Within certain limits following way :The amplitude ofthan black," and you will find this line (Baird system). the brightness of the line is pro- the carrier wave varies accordingexpressionusedsometimesto ForE.M.I.thefiguresare portional to the current in the to the degree of light in the picturedenote a value of carrier less than slightly different, but the principle electron beam, which in turn is -white parts correspondingtothe 40 per cent. figure.In prat - is exactly the same. 405 Popular Wireless, December 19th, 1936.

A feature devoted to various aspects of American broadcasting, giving interesting sidelights on the stars "OVER THERE" and microphone methods of that country

THE GIRL GAG -WRITER. no other industry that we know ofisthe second floor of a new building on Fourteenth spoilage of skilfully created material so rapid Street between New York Avenue and II Street, AN attractiveyoung womanisMabel and complete. An army of writers, production will be made into a " show placesimilar to the Wilma Albertson, brown -haired, blue- men and directors toil for a week or more at present N.B.C. quarters in Radio City, but on a eyed, pert, vivacious, full of fun.But high tension to polish up a radio presentation, smaller scale.It is expected that the studios will be has she any dates ?No. Do handsome men and after a brief period on the air the show is as ready in the early summer of 1937. buy her dinners, send her flowers, mash -notes ? extinct as the G. 0. P. in Georgia.Unlike theatrical plays, there is not even a warehouse No. Does any one, in brief, make love to her ? THE UNFINISHED SYMPHONY. No. for radio features that have completed their What's the matter with Miss Albertson's usefulness. Once a radio show has ended it THERE probablyisn'ta musiccriticor gentlemen friends ?Are they blind ?No. passes into an oblivion that is as black as the programme annotator who hasn't heard future of an amateur who gets the gong on his thecalltobelittlethe " Unfinished " Are they deaf ?No.Are they senile ?No.. first bar of music. Symphony. And many have heeded. Are they impervious to feminine charm ? This tremendous turnoverisoneofthe They have heard the popular piece so often No. Are they, in brief, fireproof ? No. peculiarities of radio.In the old vaudeville they think it's time to be passing to greater The troublelies with Miss Albertson, or days, patrons returned to the theatre time after symphonic accomplishments, and they'dlike rather with her profession.Miss Albertson is time to see their favourites run through the the crowd to follow.Yet in 100 years they have a gag -writer, America's only smooth -faced, same routine. But you can count on one hand had little success.About the time they have non -cigar -smoking gag -writer ;in other words, the number of radio sponsors who have dared noted progress in diverting interest to some other bring back a successful script :" The Barker " masterpiece, along comes a request programme- our only girl gag -writer. is ono exception; Lawrence Holcomb's "Sky- the votes pour in and the commentators dive And in her day she has collected and con- scraper " is another.Both plays lost nothing into their Schubertiana volumes for something new cocted so many jests and gibes and cracks and in their repetition and were eagerly followed by to say about the symphony Schubert started and comebacks on the inexhaustible theme of that listeners who in the first instance appreciated never completed. little thing called love that it is impossible for a play cleverly adapted for the radio and in the After all that's been said and written about her to listen, straight-faced, to men whispering second example applauded a script prepared the symphony's lack ofpower and all-round sweet nothings into her jaded ears. especially for radio. Why then is it considered orchestral merit, itisstill possible to poll the concert audiences andfindthatthe " Unfinished " isstill well entrenched " It's the penalty a woman pays as a favourite. for being in this racket," she says at FACSIMILE TRANSMISSION (So says a writer in theWashington her cosy apartment, 315, Central Park Post.") West. When a man pays yob a pretty compliment,tells you that you are the answer to a bachelor's A DEVOTED LISTENER. EDWARD MCHUGH, N.B.C.'sGospel prayer, the hottest thing this side of Singer, believes that of all his thousands the Mojave Desert, you can't get of fan followers, his most devoted listener funny and expect to get away with it. is Rex, his three -year -old Belgian shepherd dog. " Humour isdeath on amorous When the Gospel Singer is on the air, dalliance.It's bad form for a girl to according to his wife, Rex curls up in front of the radio until the programme is over. If keep her eyes open while she's being Mrs. McHugh should become so preoccupied kissed, but if she giggles she's out. with her household duties as to forget to Take this business of compliments. turn on the radio at11.45 a.m., E.S.T., When a fellow says to me, You've when her husband goes on, Rex will whine. If the whine goes unnoticed, the dog tugs got a prettyfoot,' I automatically on Mrs. Mollug,h's apron and leads her to come back with,Ah, a dog -fancier!' the loudspeaker. Rex isalso a discriminatinglistenet. " When he says, Your teeth are He can distinguish his master's voice from like pearls,' I ask,When were you any other, the McHughs say. out with Pearl ? 'If he likes my hair, The McHughs and Rex live in Newton, Take the Mass., a suburb of Boston, but the Gospel wants a lock of it, I say, Singer isin New York from Monday to whole darned wig.'If he admires Friday broadcasting from Radio City. my new, smart, daring evening gown, Rex seems to know when Friday comes I say, " It's a biblical dress-low and around.When the door is opened for him An operator transmitting a messageinfacsimile over the new in the morning, he dashes to the garage behold !' When he says,Mabel, I R.C.A. ultra -short-wave circuit between New York and Philadelphia. to remain until Mrs. McHugh takes the car want you for my wife,' I ask him, out to meet her husband at the station. What on earth would your wife do Rex takes no chances on being left behind. with me ?' " You see, I know all the answers, and it's unwise for Jack Benny to repeat his most All the cards in my joke -files successful half hours ?If the fifteen hits of the a foul curse. week which have already been heard a hundred GIFT BOOKS FOR THE keep turning over and over in my head.I've times in the preceding seven days can attract been banging out this kind of stuff so long, I'm a large audience why can't the best Vallee MODERN BOY so thoroughly trained as a gag -writer, that the Variety shows be broadcast again ? BOOKS make ideal presents for boys. Here miserable old puns, the tired tag -lines, just are three volumes that are certain to pop into my noodle. It's involuntary. 1 can't The reason undoubtedly is that every sponsor please, and willbe enjoyed and re help myself. And do men likeit ?They has a naive idea that all available listeners are read long after other gifts are forgotten. detest it, and I don't blame them." tuned to his hour and that an entirely new If you know a lad who is keen on model rail- (The above is an extract from the " New York entertainment must be offered the following week in order to hold the attention of these ways, aeroplanes or boats; or is interested in Post.") prospective buyers of his product. makingthings, EVERY BOY'S HOBBY ANNUAL (6/-), is his book !It is a mine of BURNS' MANTLE. Possibly the old vaudeville appeal will return with television.With the artists then able to information on every sort of hobby, and will GRACIE ALLEN BURNS has a spacious turn on their stage personalities as aids to introduce its owner to a number of fascinating k.)fireplace,andformonthshas been their stage ability the tendency to repeat out- new interests. telling her two -year -old daughter, Sandra, standing successes may be revived. In the mean- Aeroplanes of every description, and the about SantaClaus andhisentranceinto time, the headaches of the production men amazing story of the Conquest of the Air are good children's homes via the chimney. The working at high pressure are countered by the exhaustivelydealtwithinthesplendid other day Gracie asked Sandra, in the presence glee of the script writers who care little whether MODERN BOY'S NEW BOOK OF AIR- of George, " And whoisit,darling,that the life of their weekly stunts is only fifteen CRAFT (6/-).In word and picture, the story comes down the fireplace at midnight ? " minutes, as long as the checks are good. of one of man's greatest achievements is un- To father George, Sandra replied :" THAT * * * folded to form a book of endless fascination. man ! "* * NEW STUDIOS. The MODERN BOY'S ANNUAL (6/-) con- tains a wealth of good things. There is stirring FROM THE " NEW YORK SUN." PLANS fornew studiosinWashington, *VEIL dodo is extinct.So is last night's pro- D.C., which are to embody all engineering fiction of mystery and adventure, articles that gramme.So is nearly every programme advances in recent years were announced are guaranteed to enthral, and powerful illus- once you hear the announcer say, " And last week by Lennox R. Lohr, president of the trations, including plates in colour.All these now, until next week at this same time-" In National Broadcasting Company. The entire Annuals are obtainable wherever books are sold. 406 Popular Wireless, December 19th, 1936.

(I) It is said that television pictures are harmful to the eyes. RANDOM RADIO REFLECTIONS So are coloured ties and dictators,if you look at 'em for twenty-four hours at a By Victor King stretch. A television picture does not emit any more harmful rays than a cinema. The Problem of Set Servicing-Television Scaremongers (2) Itissaidthattelevisionpictures flicker and shiver and utbble. Mine don't and yours needn't, if you've SET SERVICING If someone invented something which got a good set. On the E.M.I. transmission T FIND the correspondence appearing in upset the smooth course of life for somebody there is no noticeable flicker at all, and the " P.W."on thissubject mighty else, Mr. and Mrs. Somebody -else used to pictures are rock steady. interesting, for I've had practical experience gather up their hammers and axes and try (3) It is said thatelectrical interference on both sides of the counter.As I think and smash that something to bits. is bad OA television. I ones told you, for a period I ran a radio But these are craftier times. Whispered I don't get any at all, although I live in shop in London-near the Empire Cinema, words have replaced weapons. London and my house is in a fairly busy to be exact. Televisionisgoing to upset a whole road.Even when and where interference It lived for about one year and cost me heap of apple -carts.Various devisers of exists it affects the picture much less than about £10 per week. But I consider it was obsolescent forms of entertainment are it does the sound, is generally at a lower money well spent, for I gained greatly level than is met with in normal wave- in knowledge thereby. I received first -band bands and can more easily be dealt with experienceofretailmarketing.andI by means of ,such devices as are sold by met heaps of people.Maybe if I'd spent WATCH YOUR WANDER Messrs. polling & Lee (di -pole aerials, etc.). snore time on the actual job itself, instead PLUGS (4) It is said that the picture is too small. of keeping a well -paid manager in socks The sizeisrelative. There is much and cigars,I'd have made a financial loose thinking in this matter.Going to profit as well. an extreme, you don't expect or want your Still, as usual, I had to do the thing in television picture to be as large as a full- style, although in this case the style was size cinema screen.You are close to it. rather bigger and more expensive than the In effect, it is as big as the cinema screen proposition could wear. as seen from the back row of seats. When Oh, yes, servicing !We did a lot of it. you have a television set going in your I had four men doing nothing else.That home, yo'u don't feel conscious that the cost a good bit, but they were good men pictures are small. Their illusion and and carried outtheirtasksefficiently. their entertainment value are complete. In those days, five years ago, sets used (5) Itissaidthattelevision.setsuse to give heaps more trouble.I fancy it is dangerously high voltages. in the fact that sets don't break down in Television sets use thousands of volts such percentages to -day that, is at the back and so do those shocking machines on of much of the present trouble. piers. -But there is very little current and A small shop selling perhaps three or it's the current that takes you over the four sets a week at most may have only Styx. one or two service calls per month, That In any case, who's going to play about isn't going to tempt them to hire a qualified Here is a hint for battery -set owners : When with the innards of a mains set of any engineer and pay him a good salary. No; joining a flex lead to a grid bias or H.T. battery kind while it is switched on ? wander plug, make sure thatthe insulation the shop assistant must also take on the reaches right down to the insulated portion of (6) It is said cathode-ray tubes sometimes duties of servicing. theplug. Whiskers of flex may come into explode. contact with those on a neighbouring plug and And good servicing in such conditions so cause " shorts."Another fact worth re- Wrong again.Theyimplode. Now simply can't exist.Even if the assistant membering isthat a loose wander plug can work that one out ! cause very irritating crackles in the loudspeaker. were quite a good technical man, he'd not Always make sure that the plugs fit firmly into (7) It is said that the B.B.C. television be able to keep abreast with the practical their sockets.The sketch below shows how a programmes are dud. side. You want continual and considerable gramophone pick-up may be used in a simple set by insertingitin the grid circuit of the This is correct. As a whole, they comprise experience to be able.to be ready to tackle detectorvalve. A three-pointchange -over poor material ineptly presented. However, any old or new set. switch, S,is needed, the moving contact going even the B.B.C. televisioniteScan't go direct to the grid of the valve. The diagrams will Now for the other side of the counter. be found self-explanatory. wrong with such items as the " lVfovietone A friend of mine wrote and told me his set News," and these alone make television a had broken down. Could I help him ? To asvo living, worth -while thing.And there are Being lazy, I 'phoned a nearby shop CONDENSER bound soon to be great improvements and (I got the address from a directory) and AND LEAK extensions of the television proa6rammes, asked 'em to send a man round.- They did particularly bearing in mind, that one day so at once, and their man had the set (not in. the very distant future) television going within half an hour of my call. will be broadcasting. The charge was 3s. 6d. That's service. (8) It is said that pictures are unnecessary. Another friend of mine himself called So are cinemas, football matches, boxing in the aid of a local shop. They paid two contests, shops, scenery, books and news- visits, then took the set away for two days. papers, and heaps of other things.But When it was returned the original fault most of us like looking at 'em-or some had disappeared and a new one was present. of 'em.Boxing Fans, would you prefer The charge was 25s. My friend protested. PU. merely to hear someone describe a FoOrd- They had another go at the set, but it still MOINNG Neusel fight to seeing the whole thing on a has this new fault and is quite unusable. ,47R44' TO To Per-UP GB - OR/D 7ERAI/NA L televisionscreen,plus a running com- So I shall have to put the darn thing right mentary ?Dance Fans, would you rather myself ! just hear the shuffle of feet and the click of heels than to hear and see the dancers ? ALL MY EYE ! going to get some punches in their over- Everybody ! wouldn't you prefer to look a lotofscaremongering drafts,obsolescent engineers who know and listen to the Lord Mayor's Show, THERE'Sgoing round abouttelevision,and all about blind radio are already finding rather than just hear, " It's a glorious think it's inspired.Or lots of, it is.In themselves dazzled by this vision which day.Crowds of people. Here comes the olden times, when men were men and has been added to broadcasting. detachment of Royal Marines.It'sa machinesthedevilitself,antagonism Let's grab sit these weeds that are being simply gloriouS day.I can see the first against new things used to adopt a more planted and pull them out before they coach. It'smarvellous, a grand sight. direct course. begin to grow. The weather's perfect " ? Popular Wircless, December 19th, 1936. 407 LEARNING FRENCH THROUGH YOUR RADIO Part 41 of our special language series By S. C. Gifford, M.A.

TENSE No. 8 (I will sell, ines, Caoutehouc, Alcool, Sucres, Laines, vendrai)istheusual Huile de lin. INFINITIVE plusTHE This week I want to give you a detailed ENDINGS -AI, -AS,-A,-ONS, report of . TWO of the above, say, POIS- -EZ, -ONT. Only, for obvious SONS and FRUITS ET LEGUMES.As reasons, the FINAL E. OF a preamble to the former the report might HE INFINITIVE IS CUT mention the quantity of fish that was for OFF. Thus : Vendrai ,vendras, sale in the market.This would be brief- vendre.,vendrons, vendrez, in fact, a single sentence.Thus : vendront. (See Part 21.) ARRIVAGES : 204,400kilos DONT SimilarlywithTENSE 180,300 DE MAREE.(Arrivals :204,400 No. 9 (I would sell, Je yen- kilogrammes, 180,300 of which aresea- drais) :Vendrais, vendrais, water fish.) vendra it, vendrions, vendriez, Then follows the reading (rather rapid High quality reproduction is one M the features of this value - vendraient,(See Part 21.) perhaps) of a variety of types of fish and for -moneyCossor radiogram.It costs only 22 guineas. TENSE No. 2 is obtained the prices they fetched. in the ordinary way. Namely, COLIN (Green Pollack) 4.50 a 14 WE have already dealt with -ER and STEM plus the IMPERFECT. ENDINGS HARENG (Herring) 1a 2 HOMARD VIVANT (Live Lobster) 12 a 24 -IR verbs.A third class of verbs- -ais, -ais, -nit, -ions, -iez, -aient. (See Part 18.) HOMARD F P I NE U X (Cray -fish) incote the -RE verbs-have to be tackled Thus : HOMARD MORT (Dead Lobster) 8 a to Though there are essential differences Vendais, venda is,veridait,vendions, LANGOUSTE VI VA NTE (Sea Cray- now. fish, alive) 14 a 20 between this class and the others, there are, vendiez, v en da Oen t. LANGOUSTE MORTE (Sea Cray- however, many points of resemblance. First fish, dead) The TWO REMAINING TENSES must R A I E (Skate) incote of all let me give you a few of the com- be studied with care.These are TENSES GROS MAQUEREAU (Large monest -RE verbs. Nos. 1 and 3.I will give you them in full. Mackerel) Ia 3.25 PETIT MAQUEREAU (Small Rompre (to break), attendre (to wait for), TENSE No. 1 (I sell, I am selling): Mackerel) incote entendre (to hear), rendre (to give back), MERLAN ORDINAIRE (Whiting) 1.50 5 3.50 Je vends Isell eah(n) vendre (to sell), defendre (to forbid), pendre tu vends etc. vah(n) SOLE FRAKAISE (French Sole)8 a 20 (to hang), suspendre (to suspend), etc. it vend vah(n) TURBOT (Turbot) 14 n. vendors rat(n)-do(ng) LIMANDE (Dab) Now, the STEM of all these verbs is v. vendee. rah(n)-det MOUL ES (Mussels) 938 oaakai1s10 110l4.50 es s1 00 off ilsvendent vah(n)d obtained by cutting thefinal -RE H U IT R ES (Oysters) 22 a 35 le 100 syllable.Thus, we are left with : ESCARGOTS PETITS GRIS TENSE No. 3 (1 sold): (Winkles) 3.508 4 le kilo ROMP-, ATTEND-, ENTEND-, REND-, ANGUILLE VP/ANTE (Live Eels) VEND-, DEFEND-, PEND-, SUSPEND-. Je vendis - I sold vah(n)-dee ANGUILLE MORTE (Dead Eels)4 a 6 tu vendis etc. vah(n)-dee From these STEMS the PRESENT PAR- 11 vendit vah(n)-dee n.vendimes vah(n)-deem FRUITS ET LEGUMESFruits and TICIPLE is obtained by adding the usual Vegetables. Thus : v. vendites vat(n)-deet syllable -ANT. ils vendirent vah(n)-deer BANAN ES (Bananas) 360 a 380 les cent ROMPANT, ATTENDANT, ENTEND- kilos ANT,RENDANT, VENDANT,DE- Now to add to your vocabulary.To the POIRES (Pears) 450 a 700 FIGUES FRATCHES (Fresh FENDANT, PENDANT, SUSPENDANT. average Englishman" Prices ranged as Figs) 250 a 700 To get the PAST PARTICIPLE (and follows " is the signal to switch London off. POMMES (Apples) 100 a 250 ORANGES DE BRFSIL (Brazil this is one of the main differences between But to the Englishman " Learning French Oranges) 90 a 110 la caisse -RE verbs and verbs of other conjugations) Through HisRadio "" VOICI MAIN - PITCHES (Peaches) 700 A 900 YOU ADD U TO THE STEM.Thus : TENANT LE BULLETIN COMMER- NOI X (Walnuts) 400 a 500 TOMATE (Tomato) 70 a 110 ROMPU (broken), ATTENDU (waited for), CIAL,"or" LES COURS COIVIMER- AIL (Garlic) 300 a 400 ENTENDU (heard), VENDU (sold), DE - CIAUX." or " LES PRIX DE CLOTURE A RTICHAUT (Artichoke) 20 a 80 le cent CA ROTTE (Carrot) 50 a 80 lescent FENDU (forbidden), PENDU (hanged), DE NEW YORK," etc., etc., is an oppor- bottes SUSPENDU (suspended), RENDU (given tunity for acquiring a bigger vocabulary NAVET (Turnip) 25 A 80 that is not to be missed.These bulletins OSE IL L E (Sorrel) 30 a 80 back). F PI NA RD (Spinach) 40 a 70 It is important to remember how this.are read daily and at frequent intervals POI RE A U X COMMU NS (Leeks) 100 5 150 les cent PAST PARTICIPLE is formed, because during the day.Consequently, the con- bottes POMMES DE TERRE DE HOL knowing this enables you to write down the scientious learner is able to master a big LANDE (Dutch Potatoes) 40 aSO lescent FOUR COMPOUND TENSES ofthese vocabulary in record time.And with a kilos LAITUE (Lettuce) 5 a 40 le cent -RE verbs straightaway. good accent, too ! HARICOTS VERTS (French These bulletins treat of a number of Beans) 80 a 280 J'ai ROMPU Ihave broken, etc. commodities which are, of course, classi- POTS VERTS (Green Peas) 50 a 120 let. cent J'avais ROMPU I had broken, etc. kilos J'aurai ROMP U Iwill have broken, etc. fied.What excellent practice with your MELONS (Melons) 1 5 2.50 la piece J'aurais ROMPU I would have broken etc. numerals they give you as well ! But what of the other FIVE TENSES ? Here are some of the commodities whose D'autres Fiuits et Legumes sont Some of these should present no difficulty pricesare quotedin every bulletin : LE CHOU (shoo) Cabbage LE SEIGLE (Wig!) Rye whatever, if you apply to them your know- Fruits et Legumes,Fromages, Oeufs, LA BETTERAVE (bet-trate) Beetroot ledge of -ER and -IR verbs.Let me deal Beurres, Poissons, Volailles, Pore, Mouton, LE RADIS (rah-dee) Radish with them in their order of simplicity, Viandes, Veau, Orges, Avoines, Bles, Far- (Please turn to page 419.) 408 Popular Wireless, December 19th, 1936.

Course in Wireless."It costs 4/-, and is published by Sir Isaac Pitman & Sons, Ltd. BOOKS FOR THE RADIO MAN Actually the book is a reprint of a series of articles which appeared in " World Radio " TestingRadio Sets-Servicing Superheterodynes- under the title of "The Radio Circle for Beginners Only." Written especially for Accumulator Charging-AFirstCourseinWireless-. those possessing no technical knowledge and avoiding mathematics,it forms an Modern Radio Communication excellent introduction to more advanced text books on wireless. Many " P.W." readers will appreciate this book. THOSE who are interested in radio in of battery receivers :in fact, by far the Then we have J. H. Reyner's " Modern its many and varied aspects are well greater percentage of sets in use to -day Radio Communication," also published by catered for these days by the wide are of the battery type.This means that Sir Isaac Pitman & Sons, Ltd., and priced selectionofbooksthat is available. a big business is done in charging L.T. at 5/-.This book is written so as to cover During thelastfew months we have accumulators, but it is also a regrettable the requirements of the preliminary and received a number of useful books, and fact that in a number of cases batteries intermediate grades of the City and Guilds this week we propose to deal with some of are badly charged through lack of know- of London Institute, and is also suitable them. ledge on the part of some of those who under- for candidates for the P.M.G. certificate. The servicing of receiversisa very take this work. An elementary knowledge of electrical important branch of radio.Although the Obviously,the man who thoroughly phenomena is assumed, but the author modern wireless set is on the whole a very understands this branch of electricityis deals with the principles of alternating reliablepieceof machinery,faultsare currents and in- nevertheless liable to develop in exactly cludeschapters the same way as they dd" in other types of FINDING THE EARTHED MAIN oncapacitance apparatus. and inductance. Consequently the service man must be Supply Mains Supply.Ma ins There isalso a well equipped with the knowledge necessary \Earthed very useful to enable him to carry out all the tests for Main chapter on localising and curing the fault. For those vectors,which whose work lies in this direction there is a students will comprehensive book by J.H. Reyner, findhelpfulin B.Sc., A.C.G.I., D.I.C., A.M.I.E.E., called connection with "Testing Radio Sets." This book has now A.C. work. run to its third edition and it covers the Dark fieldof fault finding in a very thorough manner. In addition to chapters on H.F., L.F., Cable from Cable to tuning tests, etc., mains apparatus, short Fuse Board Lamps waves and superhets are also discussed at Bright length. These two sketches are reproduced from W. S. Ibbetson's well illustrated book on " Accumu- The second section of the book is devoted lator Charging and Maintenance and Repair." to laboratory tests and the information The top one shows the method of finding the given will appeal to those employed in earthed main, and that on the right depicts an accumulatorjoinedtothe terminalsofa A radio factories as well as to the service man. lightingswitchfor chargingpurposes. The In this section there is a chapter on the switch, of course, must be off." cathode-ray oscillograph, a device of great value in laboratory test work. the one who isgoirg to establishhis " Testing Radio Sets " costs 10/6d., and business on a sound baSis. is published by Chapman & Hall.It is One of the best books we have met written in a clear and practical manner, dealing with accumulator charging is that and this, the third and revised edition, by W. S.Ibbetson,B.Sc.,A.M.I.E.E., should achieve even greater popularity which has now reached its than the two preceding ones. fifthedition(" AccumulatorCharging Maintenance and Repair," published by \Light Switch with ALL ABOUT SUPERHETS Sir Isaac Pitman & Sons, Ltd., price 3/6d.). Cover Off While on the subject of servicing we It is essentially practical and includes would mentiontherevisededitionof numerous sketches and circuits.It covers " Servicing Superheterodynes " by John F. the charging and upkeep of accumulators Rider.This is an American book, but it for wireless work, motor -cars and cycles, can be obtained inthiscountry from andalsocountryhouselightingand Holiday & Hemmerdinger of Manchester. machinery plants. The price is 5/-. We have taken the liberty of reproducing The author goes right into the whole two of the sketches which appear in the basic principles of the superhet and deals book. with the various types of circuits used in For the benefit of candidates taking the superhet design.The book isspecially " Motor Vehicle Electrician's Course " of BatteryOf? valuable in view of the wide popularity the City and Guilds of London Institute, Charge of this class of receiver at the present time. parts of the syllabus relating to battery Those whose work calls for a specialised work, together with the questions set at knowledge of the superhet will find much the recent examination, have been included. useful information in this book.It must In addition to the maintenance and be understood that American terms are repairof standardtypesofbatteries, used throughout and commercial circuits there is a chapter on alkaline cells of the where referred to are also American, but Edison and Nife "types.Those who Thisisnot a book forthe absolute this does not affect the principles upon which study this book will get a really good beginner who is only interested in the theoperationofthesuperheterodyne grounding in battery work. broadcast reception aspect of radio.It receiver is based; which are, of course, the is intended to help the serious radio en- same all the world over, WIRELESS SIMPLY EXPLAINED gineering student, and as such forms an * * Turning now to text books dealing with excellent companion to the second and BATTERY CHARGING the theory of radio, we would mention that moreadvanced volumebythesame There are in this country many thousands simple book by" Decibel "-" A First author. Popular Wireless, December 19th, 1936. 409

THESEfirst opened with twenty minutes of variety television which was just like any normal variety programmes show. v;hich are coining There were two singers, a cross -talk act, over theairare a mimic and a comedian. A fine little bill, not,judged as thistimewellpresented. At twenty programmes,particularlygood. Their minutes past nine the National programme presentation is often crude and childlike, came in with its Saturday evening variety. and the frequent bad timing is only one and so there was continuous variety from aspect of their generally poor production. nine o'clock until twenty minutes past ten. And yet they contain many first-class Other evenings it is very useful to be items. Starsofvariety,extracts from A high -efficiency all -mains set for the able to turn to the ultra -shorts as an alter- current plays, British Movietone News and televisionprogrammesand ordinary native to the fare that is being offered on so on, which constitute immensely attrac- broadcasting-an entirely new receiver the mediums and longs. tive entertainment. for everybody, which can be built and A complete television outfit costs about It is a curious fact that for the most part operated by anybody. one hundred pounds, but a set capable of they can be enjoyed by sound alone without giving you the sound part may not cost as the accompanying vision.Given any hour Anyway, whatever it is, those who are many shillings. of the television programmes, there will be unable tolistento thetelevision pro- but a few minutes during which the pictures grammes as well as to the ordinary ones Outstanding Performance appear to be essential. are missing a great deal of good stuff. We But better still is to have a set which will Why the Programmes Are Better bring in both the ordinary broadcasting Much of the material merely listened and the Alexandra Palace transmissions. to even seems to be better than its Such a one is the " A.P." A.C. Three. equivalent in the normal programmes. This is, as you will no doubt have gath- There are two possible reasons for this. ered already from the illustrations, an all- The firstis that the listener, knowing, mains three -valve set.And itis a high - that there is in fact vision to be efficiency set for the reception of the normal picked up out of the ether, if only medium-andlong -wave ' pro- he had the picture -receiving gear grammes.Indeed, in view of the as wellas the sound -receiving fact that it is also an extremely apparatus, hashis imagination effectivereceiveroftheultra - stimulatedsubconsciouslyand short waves, itnaturally follows fits in his own imagined pictures that it provides an outstanding per- of what is going on. formance on the lower frequencies. The second is that the artists, No,itis no ordinary three conscious that they have to get valve set.With itsthree pen- over visually as well as aurally. todes and carefully devised layout, put more into their acts.And, it provides a magnification of an of course, they are unable just to exceptionally high order. speak or sing with their mouths the You may be wondering how it while their eyes wander around ispossible t to handle so widely the mike and its surroundings and di versefrequencieswiththe to and from scripts held in their majority of the components serv- hands.Their acts must be one Although providing an additional field of entertainment the " A.P." A.C. Three ing for all the bands. hundred per cent for the audience. is in every way as simple to operate as an ordinary two -band receiver. Well, it wouldn't be possible if No expounding of dramatic lines an attempt were made merely to while they make faces and wink at the remember a recent Saturday evening.At take in the ultra -shorts by adding suitable announcer! nine o'clock the television transmission (Continued overleaf.)

YOUR "A.P." A.C. SHOPPING LIST 2 Wearite " Unigen " coils. 1 Dubiler 01-mfd. fixed condenser, type 620. 1 Bulgin toggle on off switch, type S.81. 1 Polar 2 -gang Midget tuning condenser, each section1 Dubilier '001-mfd. fixed condenser, type 670. Bulgin twin fuse holder (with 1 -amp. fuses), type 0005-mfd. 2 T.C.C. '002-mfd. tubular fixed condensers, type 300. 1 Polar V.P. horizontal drive for above. 1 Dubilier '0001-mfd. fixed condenser, type 665. F.16. 2 Clix chassis -mounting 7 -pin valve holders, type V2.1 T.C.C. '00005-mfd. fixed condenser, type M. 1 aluminium sheet, 14"X 10"-18 S.W.G. (Pete - 1 Clix chassis -mounting 7 -pin valve holder, S. W. type.1 J.B. 0003 -mid. solid dielectric differential reaction Scott). 1 Clix chassis -mounting 4-pM valve holder, type Vl. condenser. 1 yd. single screened flex (Peto-Scott). 2 pieces 4" plywood 91" X 4j" for side supports 1 Bulgin H.F. choke, type H.F.8. 1 Erie '5-meg. resistance, I -watt type. (Pete -Scott). 1 B.T.S. H.F. choke, type U.H.F.1. 1 Erie 100,000 -ohm resistance, 1 -watt type. 1 piece 1" plywood 131" X 41" fot front support 1 J.B. baseboard trimmer, '0001 mfd. 1 Erie 8,000 -ohm resistance, 1 -watt type. (Pete -Scott). 1 Varley pentode output choke, type D.P.9. 1 Erie 1,000 -ohm resistance, 1 -watt type. 1 piece 2," plywood 14" 41" for back support (Pete - 1 Wearite smoothing choke, type H.T.12. 1 Polar-N.S.F. '25-meg. resistance, 1 -watt type. Scott). 1 Varley mains transformer, type E.P.20. 1 Polar-N.S.F. I-meg. resistance, 1 -watt type. 1 Dubilier 4-mfd. fixed condenser, type L.S.A. I piece ,1 'ebonite to make 3' diameter switch -disc 2 T.C.C. 8-rnfd. wet electrolytic condensers, type 802.1 Polar-N.S.F. 50,000 resistance, 1 -watt type. (Peto-Scott). 1 T.C.C. 50-mfd. electrolyticcondenser,12 -volt1 Polar-N.S.F. 150 -ohm resistance, 1 -watt type. Brass for contact strips (see text). working, type F.W. 1 Dubilier 50,000 -ohm resistance, 1 -watt type. 6 B.A. screws and nuts, wood screws, flex, etc. (see 1 T.M.C. 2-mfd. fixed condenser, type 40. 2 Dubilier 20,000 -ohm resistances, 1 -watt type. text). 2 Dubilier 1-mfd. fixed condensers, type B.B. 1 Dubilier 5,000 -ohm resistance, 1 -watt type. 5 Belling and Lee terminals, type R. 1 Dubilier 1-mfd. tubular fixed condenser, type 4503.1 Erie 10,000 -ohm potentiometer (without switch). 6 yds. 11 m.m. insulating sleeving (Peso -Scott). 3 T.C.C. '1-mfd. tubular fixed condensers, type 250.2 Pete -Scott 2l" mounting brackets with long slot. 30 ft. 18 S.W.G. tinned copper wire (Pete -Scott). 410 Popular Wireless, December 19th, 1936.

THE "A.P." A.C. THREE new ideas until, finally, the simple- switch such as is used in the " A.P.A.C. Three VALVES FOR THE "A.P." (Continued from previous page.) emerged. The other itemisthe double-acting A.C. THREE tuning -coil windings. A crude technique reaction control.By using a differential V.I. V.2. such asthis may sometimes meet with type of condenser in a cunningly clever Mazda A.C./V.P.1.Mazda A.C./S.2./Pen. fair success in ordinary " all -wave " design, manner it has become possible to obtain bands. V.3. Rectifier but the ultra -shorts call for very special perfectly smooth reaction on all Marconi or Osram Marconi or Osram treatment. You turn the knob one way for the medium NAL M.U.12. The POPULAR WIRELESS Research staff and long waves and the other way for the has been studying and experimenting with ultra -short. this problem for nearly a year now, and the The tuning is not critical.In fact, it is work was so successfully advanced that quite surprisingly easy, and the only thing ignored and you merely connect up in a this journal has been enabled to produce you have to remember is to turn the tuning normal way to the Al terminal.However, the first ordinary ultra -short-wave sets with control rather slower when you go over to should there be any electrical interference simple switching. television. of any kind, you can use a di -pole, and in The " A.P." A.C. Three is the fourth set Many of you will be able to use ordinary this case the Al and A2 terminals are both embodying the principle which we have aerials, in which case the A2 terminal is employed. produced, and we can fairly claim to have Thenormalprogrammeswillcome thisnew developmentwellandtruly through on the di -pole, so whatever happens systematised. you are fully master of the conditions. There are two novel features specially Mind you, we don't guarantee reception developedin theResearch of the television sound trans- Department which have made mission, beyond a distance of, itpractical, simple and inex- say, thirty miles from Alexandra pensive to add the exciting tele- Palace, but undoubtedly many vision waveband to- a straight- will get good signals over vastly forward receiving set. greater distances.In any case, having built and installed the Simple Switching set you are efficiently equipped Most important is the switch. -for normal broadcast reception, You simply cannot switch the and evenif you are residing ultra -shorts by means of hundredsofmiles fromthis ordinary wavechange methods. A.P., there is a probability that A couple of inches of wire will before very long you will have a havehundredsof ohmsof television station within range resistanceatthesehigh fre- and you will beall ready to quencies. And contacts that are take its programmes.And it reliable and good on medium will have cost you but a few and long waves may be quite shillings extra to possess the hopeless. required facilities. There was no short cut to It may interest you to know solutionofthesedifficulties, that theA.P." A.C. Three has and hundredsofhours were had many weeks of the most spent by " P.W." engineers in practical testing of all-as a experimenting with innumerable A particularly neat chassis layout 9a feature of the " A.P." A.C. Three. (Please turn to page 420.) THREE PENTODES ENSUREMAXIMUM SENSITIVITY

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As can be seen the circuit employs three pentodes, these giving absolutely maximum sensitivity with this number of valves.On the television sound wavelength the set functions as a detector and L.F., a simple switching scheme providing an instantaneous change -over from one waveband toanother. Popular Wireless, December 19th, 1936. 411

MAKING THE MOST OF YOUR SHORT- WAVE SET By W. L.S.

THE hardened short-wave fan is rather has an expensive all -wave set.He listens listening to is that they don't listen on the apt to regard this section as his own almost exclusively to the two local stations. right parts of the range.Between 10 and particular property and to give vent I asked him the other night why he didn't 100 metres we have an expanse of 27,000 to moans when I periodically tell him that use the short-wave side of the set, and he kilocycles ;but only small slices of that I must once more give up some space to said, " Well, there never seems to be any- vast range are populated by stations that the beginner.This can't be helped, since thing on except a lot of Morse and squeaks:" the average man wants to listen to. the short-wave clientele of " P.W." is not Between 10 and 20 metres, in actual a static affair, so to speak ;it is constantly Don't Rush Your Tuning practice, there is very little that the average changing. Iasked him to demonstrate, and he broadcast listener will want to use, other Some of you who are reading these words switched over to the 14-30 metre range and than the 19 -metre broadcast band.You reckon yourselves old hands by now ;but twiddled the knob.And did he twiddle ? will see from Fig. 1 what a very small slice you can doubtless remember when you I'll say he did !He shot round that dial of the range this actually occupies.If you wrote to me and asked me to remember like a record -breaker doing a lap of Brook - had a 10 -20 -metre range on your set, you the poor little novice and to stop writing lands. He passed over his " Morse and would find the dozen or so stations in the above your heads." squeaks " at such speed that he couldn't 19 -metre band all packed within the top This section, in various forms, has had a have hoped to identify even a strong trans- few degrees of your tuning scale. non-stop run of nine years now.I know, mission. Some of the 16 -metre stations come over quite definitely, of some scores of readers I took over the controls from him, and well during daylight, when it is too early for who started writing to me as the veriest suggested that he should behave more as the 19 -metre band to be really good ;and novices, and who went through all the if he were in a built-up area. By ordinary Pittsburgh (\V 8 X K), in the 13 -metre band, stagesofthe game, puts an amazingly until they now hold WHERETO LISTEN ONTHE10-20METRE BAND strong transmission in- transmittinglicences to this country when and do much really conditions are favour- useful work. Scores of able forit.But the the youngerreaders N good old stand-by is who are perusing this N the 19 -metreband, now will doubtless hold 0 0 O 0 0 0 0 whichwillnear I y 0 0 0 0 0 0 transmittinglicences 0 0 0 00 O 0 always produce some- O 0 -o in nine years' time, or '46 thing of interest. considerably less. N N I - For those who All this preamble is /.2ra /f/./.) 20m haven't acquiredthe just my excusefor latest fashion, which starting off once more Fig. 1.-How the 10-20 metre waveband is divided up.It will be noticed that broadcasting is confined to is tosniffatthe what appear to be three narrow bands.Actually these bands occupy an appreciable kilocycle coverage from the beginning and and contain numerous statio,:s. amateur transmit ter tryingtoextend a and to regard him as a helping hand to those who have just fallen slow, lazy turning of the single -knob control childish sort of pest, the 10 -metre amateur for the short waves for the first time. I tuned in, before his goggling eyes, seven- band will produce some interesting things to In " P.W." we have had the S.T.800-an teen stations. Then I made him do the same. listen to.Between 2 p.m. and 6 p.m., even all -wave set for the home -constructor which True, he could only find seven of them, but On week -days, this band is pretty lively, and will be the means of introducing thousands that was more than he had ever done before. there are a number of good 'phone trans- of listeners to the short waves. In the radio So there is the first lesson for you. You missions from America.Just below10 trade we have the great boom of the " all - will never make anything of short waves if ' metres one can hear the American 'police wave " cult.And all round us we hear you don't use a little intelligence in handling cars talking with their headquarters stations broadcast listeners with old-fashioned sets your controls.Figs. 1 and 2 show roughly -the actual cars, mind you, can be clearly lamenting the fact that they qan't receive how the short -Wave spectrum is divided heard in this country. America because their set has no short- up between the various services.It is in- wave range. tended for that ;but it also shows you the An Always Active Band vast number of kilocycles -.over which you Between 20 metres and 60 metres there is Keep Abreast of the Times have to travel. rather more activity.Note that Figs. 1 A few years back they were talking about The medium -wave range of your broad - and 2 are drawn to the same scale in kilo- short-wave listeningas thoughitwere east receiver probably covers a .range of cycles, and that there is actually a lot more some crazy business, fit only for half-wits 1,000 kilocycles, at the most. Between 10 " space " between 10 and 20 metres than and scientists.It has taken some of them and 20 metres you have a " kilocyclage," if there is between 20 and 100 metres.If I twelve years or more to realise that short I may use the word, of 15,000.This means were to draw a line representing the "space waves mean something to every listener, that if one of the ranges on your all -wave between 5 and 10 metres, it would be exactly and that the man who deprives himself of set happens to cover this band of 10-20 twice as long as the baseline of Fig. 1-but them is just incredibly behind the times. metres,youmusthandlethecontrol that is another story, which we must come But this is not all.Many of those who exactly fifteen times as sloWly a's you do to later.The ultra -short waves deserVe have, in their homes, the means of receiving the control on the medium waves, if you Chapter on their own, and they shall have it. short-wave transmissions, don't make use want to tune in stations with the same de- Just above 20 metres we have the 20 - of them, simply because they won't take gree of ease. metre amateur band, which is fairly well the trouble to find out how to. "A close But 'half the trouble With thoSe who com- filled with transmissions at all hours of the friend of mine, who ought to know better, plain that .they never hear anything worth (Continued overleaf.) 412 Popular Wireless, December 19th, 1936. ON THE SHORT WAVES-Continued interesting at any particular time.This covers the winter season and should hold good for a month or so after the publication day and night.The latter part of the into their own hands and spread themselves of this issue. evening is probably the most interesting out all over the place. The heavy line covers the amateur bands time for the casual listener, since he will The result of this is that the band now only, and shows you which of them is the find American amateur telephony coming spreads from 51.5 metres down to the top most active at each hour.One portion of over at a strength as great as-and some- edge of the amateur 40 -metre band, and it has had to be dotted, since between the times greater than-that of the American even into it ! North, South and Central hours of 8 a.m. and 2 p.m. there is little broadcasting stations. American stations come in very well on this choice between 10 and 20 metres as a play- The 25 -metre band, to my mind, is a band, but it is not at its best until late at ground.From 2 p.m. until 6 p.m. there is disappointing affair. Here we have a band night.From 11 p.m. onwards thereis little doubt that 10 metres is the more of about 500 kilocycles allocated to broad- always something to listen to. interesting of the two. casting, but although the published lists Up in the region of 80 metres there is manage to fill it up very nicely, one never another amateur band, but the average A Day with the Amateurs hears half the stations that are printed in listener won't findthis very interesting Thus, if you are really keen on amateur them. One of the most regular transmissions except on Sunday mornings, when it is work, you can spread up a period of twenty- in the band is Pittsburgh (W 8 X K), but wellpopulatedbytransmissionsfrom four hours over the three lower bands, he is usually much better on his 19 -metre British amateurs, mostly using telephony. listening on 40 metres from 11.30 p.m. until transmission. If you look at Figs. 1 and 2 again you will about 7 a.m., changing over then to 20 The 31 -metre broadcast band is among realise that although the shaded portions metres.Some time before midday you can the high spots of the short waves.Between contain a lot of transmissions that will go down to 10 metres, and stop there till 30.43 metres and 31.88 metres there are at interest and amuse you, they occupy only 6 p.m.Between that hour and 11.30 p.m. least twenty-two stations which really can a very small percentage of the total acre - you will go back on 20 metres.And you be received-not all should be hearing something all the time. at once,thank THE BANDS ABOVE 20 METRES If you use the broadcast bands the hours goodness,butat of changinc, over are not nearly so clearly thevarious times defined ;but you certainly will be wasting ofdayatwhich your time if, for instance, you listen on 49 each one comes metres at midday, or on 13 metres at 8 p.m. over best. Keep in the shaded area and you will be Sydney (V K 2ME certainof coming across something or of Kookaburra other. fame) transmits at Just now I don't intend to go into the severaltimeson technical aspects of short-wave listening. Sundays, and may There are innumerable things that one can usually be heard on say about the choice of a set, about the type practically a n y of aerial to use, and about the general short-wave set that method of handling the gear.But until works ! The best you have found out for yourselves the im- times at present are between7and 9 THE BEST TIMES a.m.,andagain Fig. 2.Showing the allocation of the waves above 20 metres which will help you when tuning -in on the short -waves.Fig. 3 duringtheafter- (right) has been drawn to guide you on the most suitable times noon, from2.30 to listen on the various wavelengths. 60 p.m. onwards. His wavelength is 3F28 metres. Below age " of the 'short waves. There SO him are Radio Nations, Moscow, Rome, are some bands set aside for Lisbon and Madrid ;above him are Phila- telephony between some of the delphia, Buenos Aires, Millis, Schenectady larger liners and the shore, but N40 and Rio de Janeiro (N. and S. America) ; these transmissions are pretty two Daventry transmissions,two from infrequent nowadays, and you Zeesen and one from Jeloy(Europe) ; only hear them if you happen Bombay (Asia) ;and Lyndhurst and Mel- to be lucky enough to be on bourne (Australia). the right wave at the right It is a pity that Africa has no representa- time. tive in the 31 -metre band.It is almost Don't waste time, therefore, possibletoobtainone's" VerifiedAll listeningoffthe recognised /0 Continents " Certificate in this band alone. bands unless you have some Incidentally, I am anxiously awaiting the special reason for doingso. 0000,02, 04, 06:05/0/2. A4, /4 /4?20, 22. 24 first claims for this Certificate by owners of And now we come to the second 6frir the S.T.800. part of the story. Even if you do listen on these broadcast portant principles that I have been trying The 40 -Metre -Band Jumble or amateur bands, you may choose the wrong to explain, you won't derive much fun or Above this we have the 40 -metre amateur ones.We use the term " short waves " for satisfaction from the ownership of any kind band, which, to put it bluntly, is a nasty everything between 10 and 100 metres, but of short-wave receiver. mess. Telephony transmissions from this actually this part of the spectrum includes Thissectionexistsforyourbenefit, country on 10 metres are usually excellent ; wavelengthsofverywidely - differing whether you are a dyed -in -the -wood short- but in the other European countries we character. wave fanatic or just a casual listener.It is seem to have an appalling collection of There is infinitely more difference between your section, and I want to run it so that pirates and nitwits who do nothing but the performance of 19 -metre and 31 -metre you derive the most advantage from it.So make the ether foul with unpleasant noises. waves than there is between those of, say, tell me what you want in it, and I will try The mere fact of possessing a selective set 200 and 2,000 metres.After all, there is to keep it going_on those lines.One thing, doesn't help very much. only a difference of .1,350 kilocycles between however, is certain :I can't be highly tech- Listen to" 40 " and form your own the latter two ;between 19 and 31 metres nical all the time, neither can I avoid being opinion-but don't say that I recommended there is a difference of nearly 6,000 kilo- technical sometimes. it. cycles. Everyone has to be catered for, and I The49 -metrebroadcastbandisa I have tried to draw Fig. 3 so that it is a think the usual section called " Points From straggly outgrown affair.It used to ex- simple help in choosing your waveband for the Postbag," in which I deal with as many tend roughly from 49.6 metres to 47.2 the various times of day or night.The readers' letters as possible, is an excellent metres, but so great was the congestion shaded portion represents, in a very broad means of serving up something to interest that stations seem to have taken matters way, that part of the spectrum that will be everybody. Popular Wireless, December 19th, 1936. 413

FROM OUR READERS HAVE YOU AN AMUSING RADIO STORY? The Editor,POPULAR WIRELESS frequency communication be what it is to -day ? Two of the letters we publish this No, sir.May I say that we are not an occult Dear Sir,-After reading Mr. Donald society of " fanatics " with magic services and Kear's letter to your journal re " Salesman week contain humorous radio strange jargon.We are a brotherhood of men, and. Serviceman,"dated Nov.11th,I stories. We wonder how many working energetically on the subject of high - could, not possibly refrain from telling your frequency communication ;we use Simplified terms to save time ;we are, quite naturally, readers the story I heard of the fellow who, other readers have had wireless jealous of our accomplishments, though we do having bought himself a new 14-gn. set, welcome to our organisation all those who are thought that he knew everything that was experiences that raised .a smile ? willing to work with us for the express purpose to be known about servicing a receiver. of increasing common knowledge. This fellow happened to be in the com- of burning all day, and as the house and shop The Backbone of Short Waves pany of a bunch of wireless fiends one was not insured he had sent for the tire brigade. evening, and as usual was boasting of his They had been there since 3 p.m., and although May I say that the Athateur organisations of ability.Some of his listeners took every- they had cleared all the furniture out they could the world are the backbone of the short-wave not find anything.So they left at 9 p.m. world, and that it would take a good deal to thing he had to say with a grain of salt, but When they had gone I thought I would have even shake this solid skeleton. one old chap who did not know any better, a try to find out what was burning.The smell On the subject of receivers, may I say that I swallowedeverything,hook,lineand was still as strong as ever, and also the room was have personally designed a special" straight sinker sort of style, with the result a few full of a thick haze of smoke.Then I noticed receiver " that functions perfectly from 4 to 200 nights later he invited the boastful chap to thatit smelt like burning waxpaper ;alsoI metres ;it will cover the 200-2,500 metre band noticed that his set, which he had switched on, too, but I find that if one wishes to have 100 per come up to his house and examine his set had slowly got quieter until you could hardly cent, efficiency on the frequencies higher than as 4t was always blowing the fuse bulb hear it.I knew it was still on by the humming 1.5 megacycles one cannot also have 100 per every time it was switched on. noiseso I had a look at it.The cabinet was cent, efficiency on lower frequencies. Harking burning hot, and by standing in a certain position back to the subject of H.F. communication- you could see smoke coming out of the back. this is not such a simple affair after all. I then called my landlord and told him to Why such things as Dellinger and partial have a look at it.I put my hand inside and the fade-outs,skip -distances, various penetration WIN A GUINEA! transformer was red hot.Then he told me that powers of different frequencies ? When one Every week we pay one guinea for the his set had gone wrong, so he had sent it to the comes to frequencies higher than 3 megacycles, best letter, in the Editor's opinion, from a local agents.They had sent a man to repair it. do waves behave in the same way as those lower reader on any radio topic.There's no in frequency ?No, sir,they don't !And- I reason why you should not win one.So He repaired it, and he must have left something why not have a shot? shorting.When my landlord sent to them they repeat that it is only by the perseverance of Radio experiences,faultsyouhave charged him for a new transformer. Amateurs that their behaviour is discovered. found and remedied, programme opinions; I, think this was the first time that the fire Finally, may I say that as the public intrudes these areall permissible topics.If you brigade has been called because the wireless had into our " domain," so shall we keep our prestige enjoy reading what others have to say, by going down in wavelength to 5, 21, If metres, why shouldn't they find interest in some gone wrong I words of yours? One word about " Popular Wireless "-the etc., and who knows what will be found there 1 Anyway, giveus the opportunity to older it gets the better it gets, as witness the Yours sincerely, decide whether or not that letter you have S.T.800. in mind merits printing.It may even earn Yours faithfully, E. DE COTTIGNIES, a guinea ! B R S, 2562. The winner of the guinea this week is J. F. MELVIN. Mr.E. De Cottignies. 29, Gosport Road, Walthamstow, E.17. 104, Fawnbrake Avenue, Home Hill, S.E.24. IN SUPPORT OF AMATEURS When the time came for Mr. Expert to ex- The Editor, POPULAR WELL-KNOWN N.B.C. STARS amine the receiver he found that every time WIRELESS. he switched on the set, bang went another Dear Sir,-MayI,as fuse bulb.After alotof wriggling of brethren,spokesman for the many much of my valves and scratching of head, not forgetting maligned Amateurs, be the half -dozen fuse bulbs he wasted for the allowed to say a few words owner of the set, he was asked if he had on the subjectofShort found out anything. Waves and the Amateur Organisation. He remarked it was very funny that May I point out that the every time he switched on he saw a flash very first " Amateur " was and could not understand it at all, but, said Marconihimself,without he to the old chap :" By the by, have you whom Radio Science could nothavedevelopedso taken out your Wireless Licence ? " There- rapidly as it has. upon the old chap flushed and said :" No, May I point out that the I have not taken out a licence for two Amateurs werethe ones years, but never let on to anybody ! " who, driven down to the With a smack on the old one's back our shorter waves, did all the " donkey-work " and were radio expert exclaimed :" I've got the thefirstto discover the trouble with your set.They have cut you propertiesoftheshorter off at the B.B.C. for not renewing your wavelengths. The licence. That's why your set refuses to go ! " Amateurs wereever the Yours faithfully, ones to discover new pro- pertiesand phenomena Three American radiopersonalities. Lefttoright :Graham JOHNG. DEACON. McNamee, ace N.B.C. announcer and reporterEd. Wynn, the occurringintheouter greatest joker in American broadcasting ;and' Lennie Hayton, 17, Walker Street; Cowdenbeath, atmospheres, affecting high - the well-known jazz singer. Fifeshire, Scotland. frequencycommunication. The Amateurs were the ones FIRE -ENGINE FOR RADIO FAULT to develop and experiment The Editor, " Popular Wireless." with new and unusual circuits.(May I here AMERICA ON RUN-DOWN BATTERIES Dear Sir,-My biggest laugh over wireless was quote Frank H. Jones-U0 6 0 M, of Cuba, The Editor, " Popular Wireless." as follows : who designed the most sensitive and powerful Dear Sir,-I am nearly 16 years old, which I was living in rooms in the upper part of a 5, 10, and 20 -metre receiver in the world !) should excuse me from a lot.I have several house.Downstairslivedmy landlord,who Who wasitdidso much heroic work interesting experiences to relate. owned an A.C. mains set. during the disastrous floods in the U.S.A. ? Having had an interest in electricity since One day when. I came home from work I was Ifshort-wave broadcasting and reception about ten years old, last year I decided to try my surprised to see a great crowd outside my home, have reached a high standard to -day, then, sir, hand at wireless ;so I went round " hawking including a large number of children, two fire I beg to state that the credit should go to the for old sets and, as luck would have it, the first engines and an ambulance. Amateurs. man I asked (a friend) very kindly gave me- When I asked what was wrong, my landlord If they were a lot of ham-handed fiddlers, ever with a little persuasion-an ancient two-valver, told me he had been able to smell a strong scent vegetating and foolingabout,would high (Please turn to page 415.' 411 Popular Wireless, December 19th, 1936.

RADIOTORIAL QUESTIONS AND ANSWERS By K. D. ROGERS AMERICAN VALVES AND BRITISHSETS T. H: F. (Haywards Heath).-I have a gives the better results.Personally, I rather favour the direct earth if it is well made. But don't neglect who have faults with theirsets. Here is British all -mains set which works quite well. the water pipe, especiallyifitis one that goes what he says : I have been told that American valves are direct to ground. " With reference to Radiotorial inP.W.' Nov. exceptionally good, and I find that they are 21st, and the query raised by R. J. W. of Witney quite cheap.Could I convert my set to take A SHOCKING AERIAL about trouble with grid bias, from details given it seems that your reader is probably trying to use a these valves if I got hold of a suitable adaptor L. G. D. (St. Albans).-I disconnected the separate G.B. battery on a set designed for combined for the valve holders ? aerial from the lead-in tube the other day- H.T. and G.B., but has omitted to join H.T.- to No, I am afraid you would not.In the first place, outside the window, and got quite a nasty G.B. + on the external G.B. battery, and is thus not the American valves are not so efficient as the British, applying any bias to the valve or valves. and even if you could match up such things as heater shock from the lead-in tube.Why was this ? " I could not resist writing to you on this matter, currents, anode voltages, bias resistances and so I find that the earth wire from the set does as I have had a similar case myself. One of my friends forth, you would not get foundthespecialcombinedbatteriesalittle anything like theeffici- the same when dis- expensive, so he purchased separate H.T. and G.B. ency out of your set if you* '*connectedfromthe batteries and duly connected them up, omitting to join used American valves. The Editor cannot accept responsibility for manu- earth lead-in tube if I H.T. - to G.B. +, and then asked me why he was Where American valves unable to control the volume I ! (the set used a score-if it can be said scripts or photos. Every care will be taken to return happen to touch an var-mu H.F. pentode). Needless to say, when he told to bescoring-is that MSS not accepted for publication. A stamped, earthed point. The set me what he had done, or rather tried to do, I was addressed envelope must be sent with every article. able to tell him where he had gone wrong. they are carefully stan- All Editorial communications should be addressed was switched off inside dardisedby meansof to the Editor, Popular Wireless,- Tanis House, "While on the subject of faults, perhaps you constructing them so that Tallis Street, London, E.C.4. at the power plug on may be able to find space in your excellent journal they are not so " touchy " the skirting. for the following, which may be of some assistance intheircharacteristics. All inquiries concerning advertising rates,etc., to readers: In other words, they are to be addressed to the Advertisement Offices, John What you were getting Carpenter House, John Carpenter Street, London, was probably a minute " My set, the S.T.600, suddenly developed a habit less efficient, and therefore E.CA. of spasmodic weak and strong reception, which I can be more easily turned amount of A.C. passed to eventually traced to somewhere in the vicinity of out to pattern. The constructional articles which appear from the aerial and the earth the Extractor Coil. But you wouldfind time to time inthis journal are the outcome of statically.That is, the " Cutting the Extractor out of working caused that an American set with research and experimental work carried out with a A.C. supply to the set is everything to be quite O.K.Broken winding I the power and range of view to improving the technique of wireless reception. disconnected by theswitch thought, tested-no, windings quite in order, and yourswouldprobably As much of the information given in the columns of on one side only.The after much head scratching I traced the trouble to have at least half as many this paper concerns the most recent developments other main goes to the the terminals on the back of the coil unit, which, valvesagain asdoes in the radio world, some of the arrangements and power pack of the set. although fitted with insulated washers each side, yours. So even if you got specialties described may be the subjects of Letters There is sufficient in- had nothing to prevent them moving in the hole hold of or made adaptors Patent, and the amateur and the Trader would be duction orcapacitative in the chassis, andthus shorting theaerial to I would not advise you well advised to obtain permission of the patentees to transfer of energy to allow earth. to tamper with the set to use the patents before doing so. a minute amount of watt - " I removed the terminals and fitted a small piece the extent of fitting lesscurrent to flow to of rubber tubing over the portion which passed American valves.It * earth, and when you touch through the hole, a job I consider should have been would be disastrous. the earth or aerial while done by the manufacturers, and everything was quite you are standing on wet ground you are touching a O.K.Strangely enough theset had functioned A READER'S S 0 S slightly " alive 'point, and are earthing the current through another path.The shock you receive is not perfectly for many months before the fault occurred. how I " One further fault I would like to mention I Nearly every week get one or more sufficient to be harmful.In the case of the earth discoveredinafriend'sS.T.500.Itservesto letters from readers asking for back numbers lead, you were probably touching the earth lead show how important it is to search systematically. from the set and also the direct earth connection to " The set ceased to function, and after the usual of "P.W."Sometimes I can oblige, and the ground.In that case you were completing the battery tests, L.S. and valves, I tried the set without arrange for the numbers to be sent on, but earthing of the set through your body,The small the Class B valve-nothing doing. ILE. valve then occasionally I havetoturn current then went through you, and you felt the cut out-still complete silence. Driver valve cut to you-our shock. mit and set tried with 'phones as a one-valuer-still readers.Here is one request which I am I have had exactly the same with my own set. complete silence. bound to pass on-there are no copies of It is by no means uncommon and does not indicate " I had now narrowed down my field of inquiry, anything wrong.If the wall power plug is withdrawn and it did not take long to locate-detector valve " dealing withthe Simplex Two, the shocks cease, or if the switch has a double break by-pass condenser had broken-down and all signals July 6th, 1935, on hand.Has anyone of point they cease.It is merely because the mains are were passing from the anode of the detector valve not broken completely-being only broken on one back to earth.Although rather an obscure fault, my readers got a copy he can lend ?If so,_side-that the phenomenon occurs. by tracing methodically it was found in a little less please get in touch with J. P. Keene, of 57, If you hold the earth lead from the set and place than an hour. Selly Park Road, Selly Park, Birmingham. it very close to the earth wire which goes to direct " I am now waiting for the parts to build the Drop him a postcard first, please.Thanks. earth, you will find you get a series of tiny sparks. S.T.800, and will then give you my opinion on what That is the induced or capacity -fed A.C. flowing I am sure is some set." from the mains through your set and to earth.The Well, in the words of Tommy Handley, there you HERE IS ANOTHER current is very small, however, and is quite wattless. are, folks. I am pretty sure that several of you will " Willany Good Samaritan come to my find food for thought if not direct assistance in THAT BIAS FAULT that letter. I wish more readers would drop me a aid? Iwant acopy of P.W.'with the line and let me in to some of their secrets for blue -print for the S.T.600. I willsee that Imake no apology for publishingthe finding peculiar faults.It would help me out thecopy isquickly returned."-A letter from letter ofE.A. R. (Martock, Somerset) here. sometimes, I can assure you-I get some sticky E. D. Stephenson,20,Kirkgate, Liberton, It may be of interest and use to many readers ones to answer every now and then. Edinburgh.One at a time, please readers. The usual procedure, just drop him a line and let him choose which of you shall be the G.S.And, on his behalf, many thanks. TECHNICALITIES EXPLAINED-No. 33 PHOTO CELL A GOOD EARTH A device which emits electrons whenever light falls on it.A cathode is coated with T. L. (Acton).-I want a good earth for light sensitive materials which emit electrons under the influence of light and, moreover, my S.T.800. I am in a top flat (three storeys) C emit them in increasing proportion accord- axe-P/04J ing to the amount of light.Caesium is one and the shortest earth is at least twenty feet of the best coatings to use.Circuit using to a water pipe.I could get a direct earth to photo cell is as shown in sketch. The light, ground but it would be longer.Which shall varying in accordance with the image to be transmitted (as in television), is thrown I use ? on to the cathode C.The anode A has a Can I make connection to the D.C. electric high potential on it of suitable voltage.This causes current to flow through the circuit light metal conduit ? comprising the cell and the resistance R. The last question first.You can, but I should not But R is in the ordinary grid circuit of the do so.It might bring in all sorts of noise troubles. amplifying valve.Therefore, any changes Regarding the earths, I would seriously advise you in the light on 0 will cause changes in the to try both, one at a time.The water -pipe earth current through R and thereforeinthe may be all right if it is taken to a cold water pipe voltage across R.In other words the light which is a main pipe-coming direct up from the variationsfallingonthe photo cell are ground.If it is one of the " round the house " pipes transformed into potential variations in the it may prove very unsatisfactory. grid circuit of the valve and can then be The direct earth may not be so bad as it seems at amplified and transmitted by radioas first sight.I think I should try it.It is decidedly desired. long, but you can hardly help that, can you ?Try the water pipe and the direct earth, and see which * '* Popular Wireless, December 19th, 1936. 413

BUILDING A 7 -METRE voltagecontrolsthestrengthofthe signal. OSCILLATOR The crocodile clip on the screened lead (Continued from page 400.) which goes 10 the core of the lead is con- PETO-S OTT nected to the aerial terminal of the receiver, BATTERY thick, and is 4in. square.Before putting and the other crocodile clip goes to earth together t`ae container, the coupling coil terminal:If this gives too tight a coupling .T.800VERSION and screened lead are fitted to the inside of that is, if the signal is too strong even with the top as shown in diagram. The sides fit between the top KIT"A"cazad" 67'6 Complete Kit of Components exactly as FIRST and bottom and the end fits THESUPPORTINGBRACKET speeifled and used by Mr. John Scott -Taggart, overall,thusmakingthe with Koneetakit (Gratis with Complete Kit) but overall dimensions 71 in. x lesswanderplugs,accumulatorconnectors, 41 in. x II in. valves, Extractor Kit, Cabinet and Speaker. The copper foil covers the containercompletely,and KIT "B"Carriage Paid£4:14:0 should be carried round the As for Kit " A," but including set of 4 FIRST specified front edges towhichthe valves only, less cabinet and speaker, etc. panelisfitted. Thefoil KIT "CT" t:,,,f)!LiNts7TA.60-0b'II'qtbreit4V,Vreg, should be fitted by means less speaker, etc. Carriage Paid cE5f11/6. of small flat -headed brads KIT "CC"i:tR4'eRc`o'n leen t Cabinetvth voanTye,s waitg, about a in long. The amount speakerbaffleandbatteryshelf,lessspeaker,etc. Carriage. Paid £61910. offoil necessaryisabout 20 in. x12in.,and the KIT "CLL" f4t!,°,aitt 'aLl'XttewAt'IcT,e8TIV " LL " only,withspeakerbaffle,lessspeaker,etc. thickness -004 in, Having Carriage Paid £611116. drilledtheholesforthe battery leads and screened coupling lead, the container S.T.800 (Battery) is complete.The hole for FINISHED INSTRUMENT the battery leads in the side The timing condenser and valveholder are fixed to this bracket, and these two components support the remaining parts, as will be Built exactly to Mr. J. Scott- is in. diameter, and that TABLE MODEL Taggart's.specification clearly seen by reference to the wiring diagram. .Peto-Scott's expert tech- for the screened lead in the nicians. Complete withFOUR FIRST- SPECIFIED valves top is 3e in. and Peto-Scott Walnut table The panel is fitted by means of three reduced H.T. voltage, the earth crocodile cabinet (illustrated on left), less batteries. OVER- screws.It is necessary -to enter the battery clip connection may be removed.If this ALL DIMENSIONS Width 18)in.'Height144 in.; leads in their hole in the side of the con - does not reduce the signal enough, remove Depth 12 in. aerial crocodile clip from aerialterminal CASH PRICE and just leave it near by.

The position of the vision and sound t7 2 6 televisionsignalsareatapproximately CABINETONLY. Exquisitelydesignedwalnut finishedCabinet, with slopingfront and crossbanded 110° and 140° respectively.A paper dial moulding. Complete with extension spindle, 17/6. may be stuck on the panel, as shown on (Carriage and packing 216 extra.) the photograph of panel.The positions given will help to find the transmissions on NEW ANDPETO-SCOTT 1937 the receiver.When these are found the DIFFERENT! SHORT-WAVE exact positions may be marked on the ADAPTOR -CONVERTER KIT paper dial of oscillator. Convertyourbattery 13-74 or A.C. set for opera- tiononshortwaves METRES with thisup-to-the- Dimensions for the scale indicating pointer. minute unit. No altera- tions to your set. Two FROM OUR READERS hours to build-a life- tamer before fitting panel. When the panel time ofworld - wide _entertainment. has been fitted they can be pulled through. (Continued from page 413.) 111 No coil changing. Ready drilled enamelled The L.T. is, of course, a two -volt accumu- steel chassis. di Ready drilled black crys- lator, while the H.T. may be as low as without valves, needless to say, and some parts "" Wine finish steel panel. 66 volts.It is useful to use a 120 -volt for 2 6.Earphones I got for 1;6. battery,antivariationoftheapplied This collection lay idle for some time, then Cash or C.O.D KIT ifix129/6Carr. Paid. I tentatively made a one-valver.It actually got Or 2/6 down rind .10 monthly four B.B.C. medium -wave stations. payments of 31-.Comprises all partsforbuilding, with diagram, Now, after a year's experience, with a 30 -foot assembly,andoperatinginstruc- earth wire, an indoor aerial of electric -bell wire, ' tions, less cabinet. a home-made coil on a cardboard former (range 230 metres to 580 metres) and a saucepan for earth, I boast of having listened to 46 stations in THE 'A.P.'A.C. THREE the above range on the same one-valver. fif offirtsyreifiedparts,le valves.Cash C.O.D. Carriage The set has no choke and not one refinement. KIT " A Rf/5/, or monthly 153. The H.T. consists of two throw -outs of the neigh - With 4 specified valves, £1011416, or 12 monthly pea - hours and another battery about four months meals of 19/9. old. A long time ago you published a letter Irons a boy of my age telling how he heard two American W.B. 1937 SPEAKERS MODEL 37S.Amazing reproduc- stations on the medium -wave on his one-valver. tion provided by new magnet and ex - On several summer nights when daylight was potentialmouldedcone. Microlbde matching device. Cash or C.O.D. just appearing I heard in comfort by my bedside Carr. Paid £2/2/0. Or 2'6 down six Americans.They areunmistakable with and 11 monthly payments of 4./.. their strong American accents. MODEL 37J. Per. fleetlymatches any I identify my stations by means of a graph. receiver as principal The set readings are plotted against the correct orextra speaker. wavelengthsof the stations.With the B.B.C. CarriageCashor C.O.D. Paid stations whose wavelengths are known a smooth £1/12/6. Or2/6 down and 11 monthly payments of31-. curve is obtained. Any other " W.B." Speaker on attrac- Then the unknown stations, with the graph and tive Easy Terms. the help of language, are easily identified. Best wishes to " P.W." PETO-SCOTT Co., Ltd.,"(P.W aen City Road, Yours truly, Telephone: Cli.,..oid 9875. The coupling coil which consists of a single turn P. A. YEATES. West End: 62 (P.W.10),IliQllHolborn,I-otufon, W.C.I. of wire is secured to the top of the containing box. 62, Hurst Grove, Bedford. EST. 1919. 416 Popular Wireless, December 19th, 1936.

Incidentally, he mentioned that the Baird Co.hasunderconsiderationthequestion whether a new site will be found for their SEEN ON THE AIR experimentalstationor whether theywill carry on at the Crystal. Palace. L. Marsland Gander, "P.W.'s" special radio -screen correspondent, * * I went to the Alexandra Palace recently to gives his views on the B .B.C. television programmes. see a transmission from the studio end.By the courtesy of the B.B.C. I was present in the large Baird studio during an afternoon broad- I SAT in the dress circle of the Dominion that used in the Baird transmissions from the cast.It was an exciting, not to say dis- Theatre on a Sunday morning recently. Alexandia Palace, does not sound specially concerting, experience. The curtains parted and revealed a huge impressive.Yet, as I have said, at a distance I was able for the first time to see the pro- close-up of Will Hay on a screen measuring from the screen the results are altogether sur- blems of the producers in true perspective.I eight feet by six feet six inches." Good morn- prising.The lines are, by the way, vertical, do not say that I came away with the impression ing, everybody," he said and continued with as in the case of the old low -definition system that their methods were ideal, but I did carry some patter to which, I regret to say, I paid adopted by the B.B.C.The divisions could be away a wholesome respect for the tremendous little attention, because I had been taken by seen on the screen, sometimes much more effort which is being made, sometimes with surprise by the excellence of the latest super - prominently than at others. disheartening results. screen television, demonstrated personally by It was a disappointment to the Baird Co. Baird's are using alternative methods at the Mr. J. L. Baird. to be unable to transmit from the Crystal Palace moment, intermediate film and the electron Will Hay could be easily recognised, although for the purposes of this demonstration.Un- camera.At this particular transmission of he was minus the familiar mortar board.I fortunately the transmitter was destroyed in the " Picture Page " two electron cameras were do not pretend that the picture had the bright- fire, but the Company courageously decided to go being used for the first time together, so that ness,sharpness and general clarityof the ahead with its plans, and rigged up a studio films that are shown daily in this same theatre. at the Dominion Theatre in a room remote one picture could be -dissolved directly into But they demonstrated that marked prOgress from the stage, in order to give the demonstra- another as in the Marconi-E.M.I. transmissions. is being made with this problem. tion by line. Thirty People for One Broadcast In this studio the subjects to be televised How much more complex this television "Public -Address Television " stood with their faces in front of a circular lens business is than a sound broadcast may be As shown, the system was really a " public- fourteen inches in diameter, eight photo -electric judged when I say that there were at a con- address "televisionoutfit.I do not think cells being grouped round the circumference of servative estimate thirty people in the studio. it would be .suitable for any purpose at this the lens.The remainder of the apparatus is There were the B.B.C. engineers, distinguished stage. A Stalin,Hitler,or Mussolini could behind the lens in an adjoining compartment. by their smocks, Baird engineers in mufti. show his face (to one of the mighty concourses The artists stood close up to a wooden Therewere stage hands to manipulate the which gather for the modern dictator) enlarged framework, across which pieces of cotton were batteries of " searchlights," two announcers, togiganticproportions.It would bethe stretched indicating the correct position of the numbers of other officials each with their special visual equivalent of loudspeaker magnification face for perfect 'focus.Mr. Hay objected that job, and all the persons who were taking part of his voice. the cotton tickled his nose, but the objection in" Picture Page."These last waited ner- Mr. Baird produces his picture by a system was overruled. vously on a row of chairs. which he calls" multi - mesh scanning. As Mr. Baird himself came before the trans- An atmosphere of great tension developed demonstrated at the Dominion Theatre it is a mitter and a greatly magnified likeness of him as zero hour approached. A whistle blew, the mechanical system which, both at transmitting was simultaneously seen on the screen over buzz died to a painful silence." Sound on "- and receiving ends, makes use of a slotted disc the stage.He then submitted to cross examina- then " Vision On " flashed up in red on an in combination with a high-speed mirror drum. tion by telephone from the dress circle, so that electricindicator.Then astudioassistant The finalfield gives120 -line definition, and his interrogators, myself among them, could began to turn over the pages of the " Picture pictures are transmitted at 331 frames a second. see and hear him answering their questions. Page " book in which the names of the editor I noticed very little,if any, flicker.The He told me that he had been putting in a definition, when it is realised that it is only half great deal of personal work on this system. (Continued on next page.) dtittlf

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0-12 the ideal gift for radio enthusiasts.With the 0-120 0-240 aid of this accurate meter you can keep the 0-000 performance of your set up to concert -pitch. 0-600 It enables you to go straight to the cause of trouble in all receiving apparatus.Actually the D.C. AvoMinor is thirteen testing meters in one. It gives 13 different ranges of direct 0-10,000ohms readings in milliamps, volts and ohms. You 0-60,000 r :0-1.200,000 .. can put your finger quickly on every defect. megohms No other instrument at the price enables you rII 0 to test with such ease and accuracy. In its handsome presentation case, complete with instruction booklet, the AvoMinor is the radio man's supreme gift. From all good dealers.But if you have any difficulty in obtaining, send to us.

Radio Servicing Simplified' 5thEdition. Revised and Enlarged. Another welcome gift!This book explains radio Testing from A to Z in non -technical language.Describes all the faults that sets can develop, and shows how to trace them. 13 ACCURATE METERS IN ONE Contains numerous diagrams andgraphs. Acknowledged tobethe most Fully descriptiveliterature on the AvoMinor post freeon request. usefulbookofitskind. Send 216 Postal Order for a copy to -day. THE AUTOMATIC COIL WINDER & ELECTRICAL EQUIPMENT CO., LTD., Postage 3d. Winder House, Douglas Street, London, S.W.I. Tel:Victoria 3404/7. Popular Wireless, December 19th, 1936. 117

SEEN ON THE AIR the drain on the L.T. battery is not too Rival Methods of L.F. Coupling appreciable. Resistalice-capacity Coupling, trans- Continued from previous page.) former coupling and choke -capacity Aerial and Earth Efficiency and producer are given.Yes, there is a real coupling viewith one another forthe book and it has to be " turned over " physically. People do not realise how the aerial and favour of constructors and each system has We then looked to another corner where earth may vary considerably in efficiency its own supporters.During the progress Joan Miller sat at her model switchboard in owing to weather conditions, and so on. of broadcast reception in the past few thefieldof another camera.She did her telephonic announcing and so-on with the It may be that the aerial insulators are years the changes have been rung pretty show.Prince Obolensky, the Oxford Rugby covered with dirt and that the signal input successfully on these different forms of flyer, and Laborde, the Cambridge captain, energy is being by-passed in consequence. coupling, first one then another.There is were the stars in this particular bill.Prince Again it may be that the earth connection a good deal to be said for all of them, Obolensky told me afterwards that hefelt has become inefficient owing to the ground and it really depends, apart from personal extremely nervous, but his companion, despite a prize black eye-his fifth sustained on the being dry in the regionof the buried preference, upon the actual conditions in Rugger field this term-said he felt no qualms. earth plate. anyparticularcase. Choke -capacity All these points, however, are easily gone couplingisconsidered to have certain I have left little space to discuss programmes over, and it is always a good plan to check advantages over resistance -capacity coup- -a pity, because the boys at A.P. are striving off in the ling.The connections, by the way, are desperately hard.I do not mean to sound them in cases of any falling patronising, but this happens to be the plain strength of reception, especially if the cause the same, but the advantage is that the statement of honest fact. is not apparent from an examination of the choke has a relatively low D.C. resistance There has. been a marked improvement in set itself. (Continued overleaf.) material.My personal choice of the tit -bit of the week is Gillie Potter, whose illustrated lecture will obviously be a godsend to television and has always been a joy to me. A Conspicuous Success Mr. Stephen Thomas made a conspicuous success of the model parade when £2,000 worth of dresses-all British designed-ranging from skiing outfits to alluring evening gowns were shown. OVER TYPES There is, by the way, another reflection on 50 my studio visit which I must make. A show which may seem marvellous in the studio, full of pep, wit, and everything desirable, may be Every Battery and Mains Set can be agonising to the televiewer gazing at a small vastly improved provided you replace screen ten miles away.To me it seems a great drawback that the producer cannot see con- all"tired" valves withtheirmodern veniently and immediately, at every stage, exactly 'what picture he is producing.He can Hivac equivalents. nip into the next room ;he can get somebody to tell him.But a check receiver under his nose seems to be the only real solution. Why put up withdistortion,lackof Other high spots of the week were the Two Leslies and George Scott -Wood and His Six volume and sensitivity, when for a small Swingers.I must regret that I did not see " Hutch." sum you can modernise your receiver. I notice that another improvement has been toalternateGaumont-BritishNewswith British Movieton3 News, thus avoiding' endless repetition of the same reel.Nice work. 1 VA TECHNICAL JOTTINGS Items of interest to all TI -1L SCIENTIFIC By Dr. J. H. T. Roberts, F.Inst.P. WAVE Smooth Reaction TO get the best results with an ordinary " straight " type ofreceiveritis essential that the reaction comes into BRITISH MADE effect gradually instead of with a plop ;also, it is very important that when you turn the reaction control in the opposite direction, the THE SIGN OF A GOOD VALVE direction to reduce the reaction, the set should cease to oscillate at more or less the Have you had particulars of these special types? same position of the control as that at which itpreviously started to oscillate. Sometimes you will find that the set will HIVAC SHORT-WAVE VALVES start to oscillate when the reaction control HIVAC HARRIES VALVES goes past a certain position,' but will not cease to oscillate until the reaction control HIVAC MIDGET VALVES is brought a good deal farther back than the position at which the set started to oscillate. Any differencebetween the SCOTT-TAGGART USES position at which oscillation starts and that at which it stops is known as " backlash." To get smooth reaction you will some- HIVAC FOR HIS S.T.800 times find it worth while to use a potentio- meter connected across the low-tension DetailsofallHivac types sent free for postcard request supply, the slider connection being taken from a point on this potentiometer to the HIGH VACUUM VALVE CO. LTD., 111-117, FARRINGDON ROAD, LONDON, E.C.1 gridleak. Use a fairly high -resistance potentiometer, say about 500 ohms, so that 418 Popular Wireless, December 19th, 1936.

TECHNICAL JOTTINGS is to repeat the process for the next valve (Continued from previous page.) and you will find that a couple of stages will give you enough amplification to get about FOR and consequently only a comparatively seven times round the world ! small drop in the anodo voltage is produced when a choke is used as coupler. Avoid Overloading LESS THAN This is all very fine and large, but the Voltage Drop plain fact is that the amplification that can You can compare this with resistance - be obtained from a stage in practical con- id PER WEEK! capacity coupling where, as is well known, ditions isaltogether different from that The new HEAYBERD "Tom Thumb" Battery there is often quite a large drop in voltage, indicated by theoreticalexaminationas charger incorporates a METAL RECTIFIER, and above.There is a very great discrepancy will charge a 2 -volt accumulator at * amp. for less so appreciable as to necessitate providing than Id per week.Simply connect the output extra high-tension voltage in the H.T. indeed between the amplification which terminals to the battery and Insert the mains con- supply so as to allow for the drop and make you can work out on paper and that which nection into the nearest power point.By charging your batteries at home, time and money is saved, sure that the correct voltage is ultimately you can expect to get. So you will need to and the life of the battery considerably lengthened. applied to the anode of the valve. modify your ideas quite a bit and to realise The fact that the D.C. resistance in the that to attempt to get anything approach- case of an L.F. choke is so comparatively ing the theoretical amplification out of a small permits alsoof the choke being single stage will only result in hopeless used in place of decoupling resistances, overloading. especially in positions where, for one reason or another, itis important to avoid any * appreciable voltage drop in the component. But, of course, the question of expense has NEXT WEEK to be borne in mind.Choke coupling is not cheap. FROM MY ARMCHAIR SEND NOW for full Interference From Moving Coil BY details of this remark- able Battery Charger. I have sometimes been asked whether Thefull rangeof the field winding of a moving -coil speaker JOHN SCOTT - TAGGART HEAYBERD Chargers islikely to interfere with neighbouring M.I.E.E., F.Inst.P., FeI.I.R.E. maybe seen atour DELIVERY FROM components. The answer, I think, is pretty Showrooms. STOCK. obvious.% If the field magnet is excited by AND directcurrentproducedbyrectifying M alternating current, it will be evident that More About the ADDRESS unless this is very carefully smoothed it "A.P." A.C. THREE willstill be pulsating in character, and P.W will be very liable to cause trouble if any 10 FINSBURY ST. of the more sensitive components of the F. C. HEAYBERD & CO. LONDON, E.C.2: circuit are too close toit. In modern Voltage to Power Valve all -electricsetsthesmoothingofthe The valve which generally gets the brunt AMATEUR CRAFTSMEN field supply is pretty carefully worked out, of the overloading is the output stage, and PLYWOOD PANELS, ALL SIZES AND THICK- and, on top of all this, the inductance of here itisuseful to remember that an NESSES, PLAIN AND VENEERED. BEST QUALITY, ABSOLUTELY UNBEATABLE PRICES. the field itself helps greatly in the smooth- ordinary small -power valve used in this ARNOLD WOODWORKERS SUPPLY CO., ing. Nevertheless, I advise you not to stage cannot be expected to handle more la, Arnold Road, Bow, London, E.3. have any other components any nearerthan about 30 volts in the anode circuit. to the field magnet than can be helped, In passing, I may mention that according wmaioacsamaacxxxxxxxxxxxxxw and inparticular you should keep the to the theoretical calculation you may quite detectorstageandtheH.F.stages easily prove to yourself on paper that you Please be sure to mention quite clear. are going to deliver a voltage of several hundreds to the power valve. "POPULAR WIRELESS" Microphonic Effects Due to Speaker when communicatingwith Quite apart from stray electrical effects, Advertisers. Thanks! however, there is always the danger of the mechanicaleffect on the valves,which ELECTRADIX BARGAINS MICSIOMPCNICSIC:WCNSWCSICW001 used to be called a microphonic effect, COILS.-Short-wave Coils,plug -Intype,1/6each; Ribbed low -loss formers, 9d.; Long -wave 2 -pin coils, 1,-; due to the sound waves from the loud- ReactionTuners, 9d.; Mains interference, H.F. twin speaker setting the valves into sympathetic chokes, 2/-; Solenoids for model or relay operation, 6v. or 12v. with tin.loz. iron travel, 2/6. gr)7, vibration. Inasmuch as the frequency SPARK COILS, lin., tin. and its, gap, with conden- of these will be the same as the frequencies sers.Larger coils, 2in. to 7in. flaming spark, short-wave passing through the low -frequency ampli- spark transmitters for boat model control, 17/, SHORT CONDENSERS.-Variable0005-mf.Forme,1/8; fiers, you will see that there is danger of JB,0003-mf.,2/-;Reaction,-0005-mf., 1/3;Pye. WAV E -0003-mf., with sundial, 5/-; Fixed Condensers, 2-mtd., howling being set up.Itis important, 250-v., 1/- or 5/- for 6; 4,000-v.mfd., 6/-, and many enthusiasts therefore, to take care that the detector other ranges, and low -frequency stages are not subject COMPASSES.-Boat BinnacleMariners'6ln.Boat Compass,floating,gimbal glasscase, 35/-; Magnetic to the direct impact of the sound waves from Compass, ll in. Brass Case, bevel glass, plain dial, un- Illustrated construc- the loudspeaker. sealed, new, 9d.; War Office Prismatic, 25/-; Travellers' tionalarticlesfor pocket, 15/-. building simple S.W. battery sets; battery FRACTIONAL H.P. MOTORS. -300 in stock, A.C. and A.C. mains super. Theory and Practice and D.C., 1/50 h.p. toIh.p., 6-v. to 230-v. A.C. or bet. S.W. receivers D.C. front 12,43. withA.V.C. Ultra When considering the amount of amplifi- CRYSTAL SETS are popular for perfect, quiet recep- S.W. Radio Telephone; tion, 4/11; All -wave Bakelite Brownie Set, 8/11. Transceiver;S.W. cation per stage which can be obtained you Converters; Crystal - TELEPHONES.-The cheapest is a pair of 2/9 Sulli- controlled Amateur don't want to be led away by the calcu- van Headphones.Brown's " A " reed for short-wave sets, Bands Transmitter, lations which are sometimes given in text- 1,500 ohms, 21/6; Western Elec., and othcfs, 2,000 etc.From your Radio ohms, 4/3 pair. Dealer, W, H. Smith books as to the amplification which is & Sons,orfrom PARCELS of experimental odd coils. mag- Stratton & Co., Eddy- theoretically possible.I dare say many of nets,wire,chokes,condensers,switches, stone Works, Bir- terminals,etc.,postfree:10lbs..7/-: mingham,5. you are familiar with the rule of thumb 7 lbs.5/-.1.000 other Bargains in New Webb's,London service 14, Soho :- by which you take the maximum grid swing Sale List " N.' Street, W.I. of the detector and multiply this by the amplification factor of the valve and the ELECTRADIX RADIOS [ADBYSTONE1937 ratio of the following transformer, so obtain- 218,UPPER THAMES STREET, E.CA ing the volts delivered to the grid of the Telephone: Central4611. SHORT WAVE MANUAL succeeding valve.All you have to do then Popular Wireless, December 19th, 1936. 419

rtlet, and outlines simple way§ in which the menace Marche suspendu (mar -shell sfis- can be overcome.I'm quite convinced that if all pah(n)-do) market suspended those listeners who experience " frying -pan music " Cote officielle (kohl off-iss-e'el) official quotation were to obtain a copy of this booklet, the majority of Ble disponible (bleh dis-pon-eebl)corn available them would be able to solve their problems in about La Physionomie de la Bourse five minutes. (Jii-e-on-om-ee d'lah boorss) features of the B. So I propose to make it available under our free Marche ferme (mar -sleek hairm) steady market literature scheme.Just send me a postcard in the Le marche est nul (mar-sheh eh usual way, and I shall be pleased to make the neces- n fil) nothing doing sary arrangements for a copy to be forwarded to you. Le debut ((deh-bfi) opening (No. 37)11.) La cloture (klah-Iiir) close (All applications far catalogues reviewed in " The Link Between" should be addressed to 0. T. Kelsey, Now translate the following. John Carpenter House, John Carpenter Street, Landau. Apres un debut ferme, en reprise de 1.50 E.C.4, and the number given in black type at the nal of the review should always be quoted.) (on recovery of) sur la veille (day before), la By G. T. KELSEY majeure partie de l'avance se trouva reper- THOSE of you who saw the description of my due en cloture par suite de la predominance Iexperiences with the S.T.800 in a recent issue LEARNING FRENCH des offres. of " P.W." will no doubt recall my references to the Crystal Palace and to the adverse effect it had upon THROUGH YOUR RADIO Finally, a little PROGRESSIVE results in certain cases of residents living close by. FRENCH.Say the following slowly at Little did I think then that before many weeks (Continued from page 407.) had elapsed that notorious " radio blanket " would first.Then speed up. have gone for ever. And although it is perhaps a Avez-vous entendu ? little out of place to introduce sentiment Into these UNE ASPERGE (as -perch) Asparagus L'avez-vous entendu ? notes, as a Sydenham resident to whom the Palace has LA LENTILLE (lah(n)-tee'y) Lentil N'avez-vous pas entendu ? always been part of the furnishings, so to speak, its UN OIGNON (on-,o(ng)) Onion Ne l'avez-vous pas entendu end, to me, is a tragedy. As I stood up on the Parade LA C1TROUILLE (sii-roo-ee'y) Pumpkin Pourquoi ne l'avez-vous pas entendu ? on that fateful evening and saw the roof of the mighty LE CONCOMBRE (ko(ng)-ko(ng)br) Cucumber Je ne sais pas pourquoi je ne l'ai a pas entendu. centre transept crash in with a roar that could be LE CHAMPIGNON (shah(m)- Voulet-vous me dire pourquoi vous ne l'avez pas heard for miles, it was, I think, the most distressing pee-nyo(ng)) Mushroom entendu ? sight I have ever seen. LA TRUFFE (truf) Truffle Non IJe ne veux pas vous dire pourquoi je ne That I am able now to obtain generally better l'ai pas entendu. results doesn't thrill me in the slightest degree, I'm afraid, for that is mighty poor compensation for I want you to listen for these words. Have you heard the loss of such an old and familiar landmark.In I want you to catch the pronunciation.I Have you heard him ? any case, just as a matter of interest, the absorption Haven't you heard ? caused by the Palace was much less than most of us want you to try to catch the numerals, Haven't you heard him ? had reason to imagine. Certainly I have been getting too.As you read the above Bulletins read Why haven't you heard him ? better results since the great fire, but it is difficult the numerals in French, not English. There I don't know why I haven't heard him. at this stage to assess the extent of the improvement, Will you tell me why you haven't heard him ? for there are so many other things to be taken into are, perhaps. a few expressions which I No I I will not tell you why Ihaven't heard hiin. consideration.It may even be that the dear old ought to explain. Palace has been blamed all these years for something for which the hill on which it stands is directly re- Les cent kilos (leh sah(n) kee-loh)per 100 kilos A handsome celluloid dial for the S.T.800, sponsible ! However, time will tell, and Ishall La caisse (lah kehss) per case or box similar to the card dial issued in " Popular probably return to this subject when I have had a Les cent buttes (leh sah(n) 60) - per 100 hunches Wireless" but revised up to a later date little longer in which to judge.In the meantime, La piece (lah pee-ess) each, apiece I'm far more concerned with its loss. ofprinting,isobtainablefor2s.6d. In a bulletin you willhear frequently postfree, from Celluloid Printers, Ltd., Conversation Piece such expressions as: Kingston By-pass Road, Surhiton, Surrey. Talking of the Palace catastrophe, hats off to the This is the only dial approved and checked B.B.C. for the enterprising way in which they hooked In cote (a(n)-koh-leh) not quoted up a " mike "atthe scene of the fire in order to Courant (i.e. le minis courant) by the designer of the S.T.800. provide listeners with a running commentary. There's (koo-rah(n)l) current month one other O.B. that I would like them to do if it were * possible.I would like them surreptitiously to place a microphone in some out-of-the-way igloo up in the frozen North, and I'll bet the conversation when they ,1111111111111111 took us over to it would be " Iggle oogle woggle S.T.800 "-or what ever it is they say for " Have you built the S.T.800?" Everywhere I go at the present time, the one topic of conversation is S.T.800.Not that I'm the least TELEVISION INTERFERENCE surprised.I felt certain from the start that the publication of our distinguished contributor's first Type No. 300, referred to below, all -waver would result in unprecedented constructor is particularly useful for cutting out activity, and-by jingo-it has ! And despite the fact that the most elaborate the residual snowstorm effectin arrangements were made prior to the publication of television reception. this remarkable set to ensure that adequate supplies of all the necessary parts would be instantly avail- able,so phenomenal has been the demand that temporary hold-ups have been inevitable. Naturally, we are sorry about that, but I do want to assure you that everything possible has been, and is being, done by the various manufacturers to keep pace with the situation, and some of them are working day and night and right through the week- ends in order to cope with the demand with the All-wave minimum delay. There is every indication that by the time these notes appear in print the situation will be normal, and in those cases where delays have oceurred, the forbearance will be amply rewarded by the sterling Set Lead Suppressors performance of the set in question. No. 300, All -Wave, 1 -amp. type is No aerialsystem canprotect a effectual down to 10 metres 21' - That Static Menace receiver If my correspondence is anything to go by, it from interference con- Also availablefor 3 -pinPlug and Socket would seem that there are still a great many listeners ducted toitvia the mains.For fittings. who are being tortured by " frying -pan music." No.1211, Medium andLong Waves. And, unfortunately, until such times as legislation is complete suppression the mains .. 17s. 6d. introduced to deal with the situation, the menace must be filtered before they reach of " man-made " static is likely to become even more No.1256, Mediumand LongWaves, formidable in the future. the receiver, ..19s. 6d. But there is a ray of hope. I have good grounds for thinking that something is likely to be done about it officially before very much longer, in which case Thesuppressorslistedhere have there is every prospect that the situation will be been produced for conducted inter- eased. BELLING & LEE, LTD., In the meantime, I am surprised that not more ference and consist of small 3 -stage !Cambridge Arterial Road, Enfield, Middlesex readers seek a way out on their own account. After choke and condenser filterswhich STRIKE OUT ITEMS NOTREQUIRED. all, even with legislative measures, it will probably are plugged into the mains at the I" Wireless Without Crackling" booklet, FREE. be years before all forms of " man - made " static pointfromwhichthereceiver Eliminoise" folder, FREE. are completely eliminated, and In all normal cases it obtains its supply. I" InterferenceSuppression"book,Is.2d.remittance Is so easy to tackle it yourself. I enclosed. In this connection I have just received a booklet from Messrs. Belling it.; Lee, Ltd. (who are, of course, I Name the pioneers of static suppresaion) which is of very great interest to all who are in trouble with artificially I Address produced " atmospherics." BELLING -LEE " Wireless Without Crackling," asitiscalled, SUPPRESSION SERVICE I Pop. W.19.12.36 giveS a clear and concise description of the cause and gig 420 Popular Wireless, December 19th, 1936. THE "A.P." A.C. THREE priate terminal to a " 240-v." or " 250-v." tapping, the effect being to reduce the RECEIVERS, COMPONENTS AND (Continued from page 410.) normal voltage which should be on these ACCESSORIES tappings. Surplus, Clearance, Second -Hand, &c. domestic set in the home of a technician ! Now, although tapping up in this way (Continued) A memberofthetechnicalstaffof can have no illeffects, tapping down, as POPULARWIRELESS was so impressed by its SOUTHERN RADIO'S Wireless Bargains;all goods performance that he advanced a personal seen, involves a rise in secondary volts, guaranteed and sent post paid. which may mean excessive filament voltages. G.E.C.3 -valveBatterySets," Battery Compact claim on the original model while it was Besides, in a badly designed transformer Three," with 3 Osram valves, moving -coil speaker undergoing meter tests in the metal -lined the magnetising current may rise to pro- in beautiful bakelite cabinet, brand new, in sealed set -testing cabinet which is installed in the cartons, fully guaranteed;50/- each (listE5/10). portionssufficienttocausedangerous SPEAKERS.-Celestion Soundex permanent magnet, " P.W." Research Department. overheating. 10/- ; Telsenpermanentmagnet,withto -ratio Here is his report, voluntarily submitted. transformer to suit any receiver, 12/6 ;Telsen loud- speaker units, 2/6 ;allbrand new and in sealed " My Experiences With TheA.P.' A.C. cartons. Three.By H. A. R. Baxter. 1§^^-MISCELLANEOUSIN COILS.-Telsen, iron core, W349, Midget size, 4/-; " I have been using tins set in my house Type W478 (twin), 9/- pair; W477 (triple), 16/- set; at Loughton for a period of some weeks. ADVERTISEMENTS Type W476 (triple superhet selector and oscillator) 16/-set,all ganged coils complete on base with It has been used for ordinary listening and switch ;Telsen I.F. transformer coils, W482, 5/-; feeds up to four loudspeakers in various 3d. per Word Telsen dual range aerialcoils,withaerialseries rooms. 6d. per word for first words in heavy type condenser incorporated,W76, 4/-; Telsen aerial 6/- per line for displayed lines series condensers with shorting switch, 2/- ;Telsen " The performance on medium and long (12 pt. type) L. F.transformers, Type R.G.4(4 to1),3/- ;all waves is exceptional,upwardsofone brand new, in sealed cartons. MICROPHONES.-Ace (P.O.) microphones, complete hundreddifferentstationshaving been Minimum Charge 3'- with transformer, ready for use with any receiver, received at full entertainment value.The Remittance must accompany order. 4/6 each ;Ace concert microphone, complete on smoothing is of a high standard of effective- chromium stand with volume control, ready for use Advertisements for these columns are with any receiver and amplifier, 11/-. ness and the quality is superb. No difficul- accepted up to first post WEDNESDAY M OR NI NG for the following week's issue. RESISTANCES.-Tru-ohm 1 -watt, colour coded and ties of any kind have been experienced. marked, 36 assorted capacities on card ;6/. per card. The wavechange switching has not given The Proprietors have the right to refuse or AMERICAN VALVES.-A full range of valves for all withdraw advertisements at their discretion. American receivers ;6/- each. the slightest trouble and the set has been Postal orders in payment for advertise- successfully handled by all kinds of people ments should be made payable to the HEADPHONES.-Lightweight headphones,double Amalgamated Press, Ltd., and crossed. pole type, 4,000 ohms, each ear piece ;3/- pair. knowing nothing about the technical aspects REPAIRS.-Anytype ofreceivers. American, of wireless. All communications should be addressed British, etc., repaired by expert staff. to Advertisement Department, "Popular WE HavePurchasedtheComplete Component " Reception on a di -poleaerial is ex- Wireless," John Carpenter House, John Stock of a Well-known Radio Dealer and Manu- cellent, but I do not find it essential and Carpenter Street, London, E.C.4. facturer, and we are offering the complete stock in parcel lots as under have now gone back to an ordinary indoor 5/- Parcel, containing components to the value of at type. The Alexandra Palace television least20/-.comprisingchokes,resistances,coils, programme comes through at full loud- switches, condensers, wire and circuits, 5/- per parcel. RECEIVERS, COMPONENTS AND 10/- Parcel, containing components to value of at speaker strength on four loudspeakers." ACCESSORIES least 45/-, comprising variable condensers, screened The reference to feeding a number of Surplus, Clearance, Second -Hand, &c. chokes, switches, resistances, screened coils,wire, loudspeakersisparticularlyinteresting. circuits, etc., etc. ;10/. per parcel. RADIO BARGAINS. Amazingprices. All -wave ALL Articles Included in These Parcels are Brand As a matter of fact, the set was specifically A.C./D.C. Table modelsf.6/f 5/-. Halcyon A.C.7, New and Modern. designed with a view to its use in this way. £7/7/-. A.C./D.C.,Listed14Gns.. £7/7/..Mains SOUTHERN RADIO.-Branches at 271-275, High receivers from £5.Send Stamp for list unrepeatable Rd., WillesdenGreen,N.W.10 ; 46,LisleSt., That is why it is equipped with a choke - bargains. English, American valve replacements. London, W.C.2. All mail orders to 323, Euston Rd., capacity outfit. Or largely the reason, any- Full Stock all -wave Ferguson Models. London, N.W.t. way, for the type of output employed was LITTLER, theMidlanddealer,2, BarrasLane, SOUTHERN RADIO, 323,EustonRd.,London, also selected as a part of the general scheme COVENTRY. N.W.1 (near Warren Street Tube).'Phone Euston of hum elimination, for this assumes vital BANKRUPT BARGAINS. List free.Large stock 3775. importance on the high frequencies. receivers and components.Keenest prices. Butlin, CONVERSION UNITS for operating D.C. Receivers 6, Stanford Avenue, Brighton, Sussex. from A.G. Mains, improved type, 120 watts output at £2 : to : O. Sendforour comprehensivelistof S.T. EIGHT HUNDRED. Guaranteed Specified Kit, Speakers, Resistances and other components. SOME HINTS FOR THOSE £3.7.6.Extractor, £1.6.0.Specified Valves, £1.6.6. WARD, 46,FarringdonStreet,London, E.C.4. S.T. 700/800 Conversion Kit, 33/6. S.T.800 Coils, 21/-. Tele. : HOLborn 9703. ON THE MAINS Lists free.Parke Radio, Terminus Road, Brighton. Exchanges, etc. PLEASE BE SURE to mention " Popular Wireless" (Continued from page 401.) when communicating with Advertisers. Thanks 8.T.800. Author's kits, £3/7/6, A.G. versions, £8. Radio goods. Lowest prices. Part exchanges.Servwell.Wire- Suppose a transformer is working off a less Supplies, 64, Prestbury Road, London, E.7. MISCELLANEOUS 250 -volt supply, with one main coupled to HEADPHONES. Brown, G.E.C.,B.T.H.,Nesper, the " 0 " orCommon " terminal, and the Sterling, Marconiphone, etc.From 2/6 pair.Postage OFFERS ?S.T. 600 ;S.T.1.5 ;S.T.300 Star ;with other to the terminal marked " 250 v." 6d. List free. valves, little used.Telsen 28 m.a. Eliminator charger, CRYSTAL SETS. Complete. Guaranteed. Burne- 25/-. 14, Dovedale Road, Sheffield,7. We can increase the secondary volts by Jones, 5/6.Ditto, double circuit, 8/-.Large P.O. moving this main down, say,Ito the " 230-v." type,10/-. Crystal detector, complete parts,1/-. terminal,because thatisequivalent to Sensitive permanent detector, 1/6. PostRadio, SITUATIONS VACANT applying a higher voltage across the normal 183, Caledonian Road, London, N.1. " 230-v." primary. A THOUSAND BARGAINS POST OFFICE ENGINEERING.Excellent openings MAINS TRANSFORMERS, M.G. SPEAKERS, MAINS for males under 30.Start £3.13.0 weekly at age t7 Whether it is desirable to do this kind of VALVES, SHORT-WAVE GEAR, CABINETS, Etc. and no experiencerequired. FREE detailsof thing or not depends on the working con- vacancies, etc., from N.I.E. (Dept. 606), Staple Inn ditions.The point to note is, that tapping PREMIER SUPPLY STORES Buildings, High Holborn, W.C.t. down the primary pushes the secondary 20-22,HIGH STREET, CLAPHAM, S.W.4. G.P.O. ENGINEERING DEPT. (no experience volts up, and vice versa.Thus, we could SEND 3d. STAMP FOR CATALOGUE. required). Commencing 83.13.0 per week. Age 18-23. Excellent prospects.Free details of Entrance Exam similarly reduce the secondary volts by WHEN replying to Advertisements, please be sure to from moving a 230 -volt main from its appro- mention " Popular Wireless." Thanks B.I.E.T.(Dept.568),I 7-19,Stratford Place, London, W. t NICORE COIL UNITS

Four NEW CIRCUITS. We have recently published four new Circuits which are giving excellent results ;with our new ganged units.No.I (BP II l) Mains Superhet for 110 kc. No. 2 (BP 112) Battery Superhet for 465 kc. No. 3 (BP 113) Three -valve mains receiver with band-pass tuners. No. 4 (BP 114) Screened Grid Battery Three with Pentode. Blueprints now ready (BP 111, BP 112, "nrett.;7712W,2.1%-`47::" BP 113), 6d. each.BP 114, 3d. post free. .OLIVER PELL CONTROL,LTD.,BLOOMFIELD ROAD, WOOLWICH,S.E.18 December 19th, 1930 POPULAR WIRELESS iii

"P.W." LIST OF EUROPEAN BROADCASTERS This list contains the more important European medium and long -wave stations which are likely to be received in this country.There are some relay stations working on very low power and sharing common wavelengths. These have been omitted because their programmes are usually too weak or badly interfered with to be of value to British listeners.

WAVE- STATION. POWERWAVE- STATION. POWEI COCOUNTRY COUNTRY. LENGTH. MEDIUM WAVEBAND. KW. LENGTH. MEDIUM WAVEBAND. KW.

203.5 Plymouth .. ..Gt. Britain .. 0.3 349.2 Strasbourg .. ..France.. ..100 203.5 Bournemouth.. .. " .. .. 1 356.7 Berlin...... Germany .. 100 206 Eiffel Tower (Paris)..France.. .. 5 360.6 Moscow (No. 4) ..U.S.S.R. ..100 215.4 Radio -Lyons . 25 364.5 Bucharest .. ..Rumania .. 12 233.5 Aberdeen .. ..Ct. Britain .. 1 368.6 Milan (No. 1).. ..Italy .. .. 50 236.8 Nurnberg .. ..Germany .. 2 373.1 West Regional.. ..Gt. Britain .. 70 238.5 Riga ...... Latvia.. .. 10 377.4 Lwow...... Poland.. .. 50 240.2 Saarbrucken .. ..Germany .. 17 382.2 Leipzig ...... Germany ..120 241.9 Cork ...... Irish Free State 1 386.6 Toulouse (P T T) ..France.. ..120 243.7 Gleiwitz .. ..Germany 5 391.1 Scottish Regional ..Gt. Britain .. 70 245.5 Radio Marconi 395.8 Katowice .. ..Poland.. .. 12 90 (Bologna) .. Italy .. ..50 400.5 Marseilles (P T T ) ..France.. .. 247.3 Lille (Radio P T T 405.4 Munich .. ..Germany 100 Nord) .. ..France.. ..60 410.4 Tallinn...... Estonia.. .. 20

249.2 Prague (No. 2).. . . Czechoslovakia 5 415.4 Kiev ...... U.S.S.R. .. 35 251 Frankfurt .. ..Germany ..25 420.8 Rome (No. 1).. ..Italy .. 50 253.2 Nice -Corse .. ..France.. 60 426.1 Stockholm .. ..Sweden .. 55 255.1 Copenhagen .. ..Denmark .. 10 431.7 Paris (P T T).. ..France.. ..120 257.1 Monte Ceneri.. ..Switzerland .. 15 443.1 Sottens...... Switzerland ..100 259.1 Kosice...... Czechoslovakia 10 449.1 North Regional ..Ct. Britain .. 70 (West National ..Gt. Britain ..20 455.9 Cologne .. ..Germany ..100

261.1 -1, North National ., 463 Lyons (P T T).. ..France.. ..100 120 London National .. ..20 470.2 Prague (No. 1).. Czechoslovakia 263.2 Trieste...... Italy .. .!. 10 476.9 Lisbon ...... Portugal .. 15 265.3 Horby...... Sweden ., 10 476.9 Trondelag .. ..Norway .. 20 267' 4 Newcastle ..Gt. Britain .. 1 483.9 Brussels (No. 1) ..Belgium .. 15 269.5 Radio Normandie 491 -8 Florence .. ..Italy .. .. 20 (Fecamp) .. France.. .. 10 499.2 Sundsvall ..Sweden .. 10

269.5 Morayska-Ostrava ..Czechoslovakia 11.2 499.2 Rabat ...... Morocco .. 25

271.7 Kuldiga .. ..Latvia.. . . 50 506.8 Vienna...... Austria .. ..100 274 Vinnitsa .. ..U.S.S.R. .. 10 522.6 Stuttgart .. . . Germany ..100

278.6 Bordeaux -Lafayette .. France.. .. 12 531 Athlone .. . . Irish Free State 60 283.3 Bari (No. 1) .. ..Italy .. ..20 539.6 Beromunster.. ..Switzerland ..100

285.7 Scottish National . . Gt. Britain ..50 549.5 Budapest (No. 1) ..Hungary ..120 288.5 Rennes -Bretagne ..France.. . . 120 559.7 Wilno...... Poland.. .. 16 291 Konigsberg (No. 1) ..Germany ..100 559.7 Bolzano .. .. Italy .. .. 10 296.2 Midland. Regional ..Gt. Britain ..70 569.3 Viipuri.. .. Finland.. .. 10 298.8 Bratislava .. ..Czechoslovakia 13.5 301.5 Hilversum (No. 2) ..Holland ..60 LONG WAVE -BAND 304-3 Torun...... Poland.. ..24 1107 Moscow (No. 2) ..U.S.S.R. ..100 304.3 Genoa...... Italy .. .. 10 115/8 Oslo ...... Norway 60 3071 Northern Ireland 1250 Kalundborg .. .. 60 Regional .. ..Northern Ireland100 Denmark.

312.8 Poste Parisien.. ..France.. ..60 1293 Luxembourg.. Luxembourg.. 150 315.8 Breslau...... Germany ..100 339 Warsaw (No. 1) ..Poland.. .. 120 318.8 Goteborg .. ..Sweden . . 10 379 Novosibirsk .. ..U.S.S.R. .. 100 321.9 Brussels (No. 2) ..Belgium .. 15 389 Motala...... Sweden ..150 325.4 Brno ...... Czechoslovakia 32 500 Droitwich .. ..Gt. Britain .. 150

328.6 Toulouse .. . . France.. ..60 571 Deutschlandsender .. Germany . . 60 331.9 Hamburg .. ..Germany ..100 648 Radio -Paris .. ..France.. .. 80 335.2 Helsinki .. ..Finland 10 744 Moscow (No. I) ..U.S.S.R. ..500

338.6 Linz ...... Austria.. 15 807 Lahti .. .. . Finland ..150 342.1 London Regional Gt. Britain ..70 875 Radio -Romania (Brasov)Roumania .. 150

345.6 Poznan ...... Poland.. .. 16 -875 Hilversum (No. 1) . Holland ..100 POPULAR WIRELESS December 19th, 1933.

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W.re -Aft W-dr:illizrieLSISZairisl.,1,... trio.-..--liPz-zrAz--oe-weet. The Book of dEVERYDAY SCIENCE-6f-

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11 The Modern Boy's New Book of 4 iiii MOTORS, SHIPS & ENGINES 61- -,,, A big book about all that is latest and most interesting on the Liq Railway and the Sea, and Motor -Racing -192 pages of fascinating reading, absorbing articles, and splendid action photographs. The Modern Boy's New 5 Book of AIRCRAFT-6f- Flying in all its forms-the full story of the conquest of the air, presented in story and picture.Scores of photographs of land- P; planes, seaplanes, flying -boats, airships, and a fine colour plate by a famous airman artist. 4 CHUMS Annual 8'6 4,, ,4, 416 pages of reading and four magnificent three -colour plates. Book - length stories of adventure and mystery.-More than 35 short t stories, splendid pictorial articles.Bound in full cloth with two- tiil colour picture on front and three -colour wrapper. On sale at ej all Newsagents le"....411-4.76-1Orlitiletribliditlersigilkirigina.11.1NIOt.401.1P-altalliiirial and Booksellers. Printed in England and published every Wednesday by the Proprietors, THE AMALGAMATED PRESS, LTD., The Flectway House, Farriagdon Street, .London, E.C.4. Advertisement Offices :John Carpenter House, John Carpenter Street, London, E.C.4. Registered for transmission by Canadian Magazine Post."4pbseription Rates :Inland and Canada, 17/4 per annum.Abroad (except Canada), 19;6 per annum.Sole Agents for Australia and New Zealand :Messrs. Gordon OZ, Potch, Ltd.: and for South Africa :Central News Agency, Ltd.Saturday, December 19th, 1936. S.S. POPULAR WHIE-11...,S, December 260., 1931. REGISTERED AT THE C.P.O. AS A NEWSPAPER. JOHN SCOTT-TACCART WRITES THIS WEEK!

MY TELEVISION ADVENTURES Po uldr By HELEN McKAY ireless

No. 760. Vol. XXX. &TELEVISIONTIME Dec. 26th, 1936.

Also Inside : HOW TO BUILD THE " A.P." A.C. THREE Our cover photograph shows the Marconiphone Model 366, all -wave automatic radio -gramophone. It coats 36 guineas. BERGEN 352'9 SUNDSVALL 499'5 LAHTI-A-0 11107 FINLANDHELSINKI 3352 NOON IN NORWAY \ OSLO '_ STOCKHOLM TALLINN LENINGRAD 1224 1!/ ENGLAND. FRANCE. ) r "''SWEDEN MOTALA -.,,,,3a9 4/0'4 ," V i SPAIN, MOROCCO O ABERDEEN 739'5 3071 ESTNONIA\ NORTHERN IRELAND RE p SCOTTISH NAT 265.7 GOT EBORGAIA 2111 MADONA 51A e a SCOTTISH REG. 3911 KuLD1GA RIGAsss s *MOSCOW ;9g, 53, KALUNDBORG,2-50 ATHLONE NEWCASTLE LATVIA DUBLIN222 oO NORTH2674 REG.NAT. 2614. s I DENMARK rfit\I $) tt1HORSY LITHUANIA' IRELANDWEST NAT. DROITWICH "ENGLAND LONDONMIDLAND REG 2962 COPENHAGEN .255.1 KONIGSBLRRG Zs, KAUNAS 1961 WEST REG 26113734 411a HILVERSUM MX 1575 HAMBURG,?'?3013 BERLIN 3-56.7 1971....' , sC,' ANTonER HOLLAND; POZ NAN 6 *WARSAW ,3.39 RUSSIA "POPULAR PLYMOUTH .---*.-BOURNELIOUTH21195 203 .5 t? e? ': (b-e-CfLOGNE 4559 GERMANY *LEIPZIG 3..a DRESLAU sere J., IASI . 0 9'(. BRUSSELS 2.51 POLAND WIRELESS " ° LILLE ...ma 4f 4', . ' ..mrs 9 A arre FRANKFURT KATOWICE .395.6 a /--"--"-N FECAMP 260 5 ,' 't GLEIWITZ'_"-PRAGUE 2+3, 52 . 4;(0 /.. RIENNES-BRETABLI 2a, .5 LUXEMBOURG , ,", ,.. . NURNBERG'sia s '41/4e .... BRN0.32;4..1.4.1ORAVSKri-OSTRAVA , .., BROADCASTING POSTERADIO PARISPARISI 76+9EN 3..0 ,f1 III STRASBOURG -A -AA' , /STUTTGART -.2A6 'C.a., ... S C : %- - LWOW.577.# -:------MAP OF PARIS P T.T. .3,T I FF EL TOWER BEROMIUNS TER 559.6 314.2 MUNICH -s- ,134ATISLA.V.A._2.9a,a:SLOVAKICC\--...... M'IsAoLC ARraas ,.:,_ 51 ...., 5,9 206 t. 405.4 '.91.---, VIENNA -A-0 EUROPE I , BUDAPEST i.4 's a Is. .s LIMOGES 3552. LYONS SOTTC.NS.1+34 .I.:SWiTz -, RLAND -' , GRAZ 117 BORDEAUX AUSTRIA .. 2/3.4 0 ...... '.. ...,),1014TE CENER1257.;'7.-,E.MILANaas a 0, STE I.-. HUNGARYsea's:' REG; 2oa 8, ...., .. .,, R U MAN I A BRASOV 1175 MARSEILLES 4043-TURIN26GE3.2NOA 304-3 BUCHAREST FRANCE .' 4 BELGRADE.. 34,f 9r SAN SEBASTIAN 2.3s9s--,, '-`- rouLou:E.3::: 2 BOLOGN.A9,2845 FLORENCE .49 .5 YUGOSLAVIA LISBON 476 9 NI ACRID >a 410 BARCELONA VI ROME -mo BULGARIA ISTAMBUL 1612. ANKARA 1961 BARI 143 .5 LITHUANIA, SWEDEN.0 POLAND. 4;t,Z0' SPAIN VALENCIA 352-9 Z TURKEY .4V 2 P.M. IN SWITZERLAND,AUSTRIA.CZECHOSLOVAKIA. YUGOSLAVIA, HUNGARY. "4 PALERMO 531 qqV k 4LATVIA,PUMANFINLAND,ESTI4ONIA,MRUSSIP,,TUIZKEY.'Y' RABAT MOROCCO ALGERIA ALGIERS 3194 TUNIS oa Popular Wireless, December 26th, 1936. 421

AND TELEVISION TIMES

EditorG. V. Dowding Asst. Editors :A. Johnson Randall, A. S. Clark

MICRO -WAVES PLENTEE NOISEE UNDER -PAID PUSSY RADIO NOTES & NEWS SOCIETY GOSSIP NEW B.B.C. STATION HERE AND THERE Christmas -time Signal President.This vesselis moored in the It now appears that the various Berts, BEFORE the news, hereisa peace Thames within a stone's throw of Tallis Alfs, Toms, Sams, Syds, Freds, Charlies message : House. and the boys have for a long time been Will Mr. P. W. Reader, believed to Within a day of my having mentioned dancing with tears in their eyes. While they be engaged in hanging up the holly and the Edinburgh cat, Peter of the President sang of happy days, they say they were all checking over the list of Christmas presents, deliberately spat over the starboard quarter wondering how to make ends meet on the go at once to the cellar and pour himselfin the general direction of Tallis House slender pay envelopes received from the out a nice glass of whatever he fancies and,afterfluffinguphisbackhairs, B.B.C. cashier. most ? suddenly shot up the mainmast and swore They might never have disclosed this Hisbrother,Ariel,dressedinblack in a manner that no landsman could hope secret grief but for their conviction that type but with red blood in his veins, would to emulate. " It's a Sin to Tell a Lie." feel seriously injured if the festive season Inquiries show that Peter was signed on were allowed to pass without the usual Start Point the Starting Point convivial salutation. THE day of miracles, my masters, is not There isalso a navigational warning. TWO STARS over.For the B.B.C. has performed a MistletoeLight reported obscured ;all completevolt -amp. --or whatever it b(u)oys, especially in the forties, should OF RADIO is the French call it-and WE ARE to be approachedwithextreme caution ! have a Regional station in the south-west. So don't say I didn't warn you, Unblushingly, the B.B.C. has pro- ladies.And a Merry Christmas, one claimed that a start is shortly to be and all. made on ahigh -powerstationto serve as much of the south-west as Marconi's Secret possible. " Such a site,"they IT has been known for a long time gravely affirm, " has been found near that Marconi has been carrying Plymouth and, subject to Govern- out some important experiments ment approval, the station will be on his yacht, " Elettra," and now undertaken,itis hoped, in a few comes a tantalising scrap of news months' time." about what he isup, to. It seems Well, well, well !All's well that that when a newspaper man inter- ends well, but I would respectfully viewed him on the yacht, the inventor submit it's more than a few years picked up a microphone attached to that we have clamoured for this, and a micro -wave transmitter and spoke the site (near Start Point) has been the single word " No." there all the time. Immediatelyanadjacentloud- speaker said, " No .. No .. No .. No .. Tokio Testing No .. No .. No .. -seven times in OUS owners of the S.T. one second. That little word had ABITIM800 who yearn to stretch out gone round the world seven times- and grab the Rising Sun with whichissix times too many for the ease of apoet's phrase should convenience, but a marvellous demon- makeanoteofTuesdaysand stration of the capabilities of the Miss Esther Coleffian, the well-known broadcasting Fridays. Not for Shrove or Amami new method of micro -wave communications. star,at home with her Ekeo set.It is the model purposes, but because these are . the days A.C.97, a 9 -stage A.C. superhet, finished in black and ivory. on which the new Japanese 50-kilowatter Are B.B.C. Salaries Too High? will be on parade. HARD-WORKING B.B.C. officials need at only is. a month for his food, and this Testing time is from 7 to 8 p.m.On not rub their unbelieving eyes at Edinburgh business has apparently con- the wavelength 31.48, the call sign will be the above query, for it refers not to vinced him that he is under -paid by the J Z I; on 19.8 metres J Z K will be an- theannouncers andotherwell-known Admiralty ! nounced, and on 25.43;the call will be J Z J. servants of the public, but to the B.B.C. If you hear any of these stations, the cat at Edinburgh, who gets is. 3d. a week Oh, Happy Band ... InternationalWireless Telephone Co. for O-C-ing Mice. WHAT a happy New Year we shall have (Japan),OsakaBuilding,Kojimachiku, You might not think anyone would be VI' if the negotiations now in progress Tokio, Japan, will be glad to hear from jealous of this, but that's because you between the B.B.C. and the dance you. don't know Peter, the ship's cat of H.M.S. bands fail to satisfy our melody makers. (Continued overleaf.)

Next Week: TELEVISION-IS IT HERE? By John Scott -Taggart 422 Popular Wireless, December 26th, 1936.

AIRCRAFT DIRECTION FINDER FOR I.O.M.

A Powerful Hum continues to carry the greater part of the Where itisReally Cold DID you hear of the wily trader in telegraph service between Australia and GRUMBLERSat these occasional nippy Alaska who played a dirty trick on Great Britain. mornings should spare a sympathetic a visitor from 'the Arctic Circle ? thought for the radio men of Tikhaya Thevisitorhadsleighed,foot -slogged, Society Gossip Bay.Their desirable freehold residence is trekked and snow - CROYDON calling. SurreyRadio situated on Hooker shoedsome hun- Contact Club open to all interested Island, which lies dreds of miles to inshort-wavereception. Meets in the Arctic seas reach a trading post near West Croydon Station, where there tothenorthof with his furs, and is a car park. Hon. Sec., Mr. E. C. Taylor Franz Josef .Land. there had been the (G -5-X W), 35, Grant Road, Addiscombe. Erectedin1929, usual bargaining when seven men forsuppliesand Greenwich. The Harco Club meets every spentthewinter luxuries. Tuesday at7.30 p.m.inthe Canteen there, this northerly Finally, the man Lounge of G. A. Harvey & Co., Woolwich wireless station now from thenorth Road, Charlton. Own club room, free. car supportsalittle broughtout his settlementof veriest tit-bit-a rare skin of a Golden twenty-two people, including five women. Watchamacofferree or something-and the Last year a baby was born there-the trader was tempted too far ;he offered MUSIC FOR CHRISTMAS first native of Franz Josef Land since the the guileless trapper a radio set in exchange. Vikings left the locality as being much too He did not explain to the Eskimo that Under this title will be broadcast a concert made up of contributions from the various Regions. Listen- nippy, even for their hardy constitutions. it was a mains set, and that it hummed. ing to music on Christmas night is an old tradition, By means of Tikhaya Bay and the other The Eskimo, on the other hand, did not and to -day the receiving set is the modern equivalent wirelessstationsof theNorthern Sea of the minstrels' gallery.Listeners who tune in on explain that the Golden Watchamacofferree Christmas night will hear music of many different Route, ships have been able to use the skin which he left behind him had not been moods played to them from various parts of the north -of -Siberia passage during the summer. properly cured, and when that skin, in country.Each of the Regions of the B.B.C. will contribute music suitable for Christmas listening, Tikhaya Bay isalso of great potential turn, started to hum, the trader had to and music which in some way is a natural product importance as a half -way house for future close his store ! of their own part of the British Isles. air traffic between Europe and America From NorthernIreland,Wales andScotland listeners will hear folk songs and folk tunes played via thePolarroute. He Likee Plentee Noisee in their natural form, and from the studios the B.B.C. Scottish, Northern Ireland and Welsh Orchestras WITH the idea of aiding American willplay works by composers oftheir countries Microphone of Horrors exporters to sell their radio sets in based on these native themes. MOST of us have a sneaking liking for The West of England will provide a programme British Malaya, the U.S. Depart- of Christmas songs ;carols from Cornwall or Dorset - the Chamber of Horrors,or similar ment of Commerce have bean issuing shire, and perhaps a cathedral choir.The Midland means of making our flesh creep. Region will offer a selection of Christmas orchestral adviceabout the music played by the B.B.C. Midland Orchestra, And now someenterprisingAmerican kindofreceivers conducted by Leslie Heward, from the Birmingham programme director wanted by th6 studios. hasdecided to- give The North of England's contribution is a selection Chinese settlers of Christmas choral music by the B.B.C. Northern sheer horror a place there. Orchestra, conducted by T. H. Morrison, with at the microphone. Isobel Baillie and sixty members of the Halle Chorus. WhereasEuro- " Music for Christmas " will thus give listeners a He has engaged peans, the Depart- concert of music of every kind, from the chorale to an announcer with mentsays,study the carol and from the folk tune to the symphony. a sepulchral voice tone,the Chinese and the effects de- preferenceisfor partment have been noise. Theyal- park. Trams 36, 38 and 40, and buses 53, working onthe ways run their sets 153 and 108 pass within a few yards. clanking chain, the with the VOLUME FULL ON. YOU Inquiries to Mr. C. W. Kemp, 124, River creaking stair, the CAN'T HEAR YOURSELF SPEAK Way, Greenwich. grisly groan, and the drop, drop of blood. NEAR THE DARNED THING. THEIR Before the programme begins you are FAVOURITE. MUSIC IS ELGAR'S- Gravesend. Local branch of the Medway advised by the announcer to get the children YOU KNOW, THAT PIECE " LOUDER and Thames Amateur Transmitting Society out of the way, and on no account to listen STILL, AND LOUDER-MAKE THEE meet fortnightly, and have planned a in the dark.Invalids and old ladies are MIGHTIER YET " ! snappy session.Hon. Sec., Mr. Thwaites, earnestly advised to switch off ;and then " Tanfield," Cross Lane W., Gravesend. come the twelve dreaded strokes from the 'Way, Down South old clock in the tower, the phantom footstep IHAVE justbeenlookingover the Here and There and the shriek that raises every hair. annual report of Amalgamated Wireless, ISLE OF MAN.The Manx Legislature Birrrurrrrrr Ltd. (Australia), and, though I am not recently decided to establish a direc- qualified to prepare a batting -and -bowling - tional wireless station at Ronaldsway Before Our Time analysis of the figures, itis clear to me Airport.The Air Ministry is to provide ONE of the most interesting forecasts that there has been some good team-most of the cost of erection and half of the coming of radio is that made work. The number of receivers manu- the maintenance. by Joseph Glanville, who was rector factured, for example, is a record ; and a of Bath Abbey in 1766.According to a net profit of £109,701 is not a bad gate, SHETLAND. The Commissioners of letter written to the " Sunday Times," is it ? Northern Lighthouses have included in the rector penned the following words : Other high -lights are that the photo - the1937-8estimatesprovisionfora " To confer at the distance of the Indies telegram service has been extended via radio beacon station in Shetland. by sympathetic contrivances may be as London to the U.S.A. and to Germany ; * * * natural to future times as to us is a literary that works extensions have been made BRUSSELS. The leader of the Rex correspondence." and others will be necessary, and that party has announced that the voice of Sympathetic contrivance is an astonish- the new 60 -kw. broadcasting station for Rex will soon be on the air, the Rome ingly apt description of a wirelessset. Wellington has been completed. radiostation having offeredaweekly Is there on record an earlier prophecy of The submarine cables, however, are sunk broadcast to the Rexists.But diplomatic the method by which the radio miracle is deep (in gloom), for the beam radio service protest by the Government is likely. wrought ? ARIEL. Popular Wireless, December 26th, 1936. 42:l FROM MY ARMCHAIR This informal contribution by Mr. John Scott -Taggart has proved to be the most " looked -forward -to" feature in " Popular Wireless." Dealing with almost everything but the technicalities of Radio it has brought forthtributes from "P.W." readers inevery part ofthe country.

do you wish to join the Civil Service ? " Having a good lunch to -day it occurred Don't say :" Because I want a safe, cushy to me : Why should dishes be named after job with a pension at the end of it."This celebrities who do not mean a thing to radio would be regarded as in very bad taste and men ? Why not have Peche Fleming, the examining board would feel you would Oysters a la Round, or Eggs a la Eckersley ? not be a credit to the taxpayer. PROFESSORS-at any rate thosein- In the B.B.C. they ask you a similar ques- " I suppose you write because you like

terested in radio-are anything but tion.I believe the correct orthodox reply to see your name in print," suggests a the crusty fossils they are supposed is :" Because I wish to serve humanity." reader to me. to be.TheInstitutionof Electrical Dr. Mallett has turned out, or assisted in No ;after all these years-about twenty- Engineers has a Wireless Section of prestige turning out, more than half the young radio three-it makes me feel slightly sick. and importance.It has just elected a new engineers of to -day.Ten years ago I took * * * Chairman, Dr. Mallett, who is Principal of some off him.They did not know much A baby stated to be found next to a live theWoolwichPolytechnic-butbetter about radio, but that wasn't his fault.The rail on an electrified railway system owed known as a professor at the City and -Guilds crux of his speech was that for an electrical its life, a doctor stated, to the fact that it Engineering College. engineering degree you spend very little was wearing waterproof knickers. time on electricity.The syllabus would This will interest timid would-be con- Again, A Happy Choice certainly not qualify a man for wireless structors of A.C. mains sets. This is a happy choice, especially follow- operator on the Ark.One also came away * * * ing an equally happy one in Mr. Watson with rather the feeling that the Woolwich Watt-whomIrecentlydescribedas " Poly " was a good place in which to learn. The S.T.800," alleges F. R. of Inverness, Pickwickian in his bespectacled geniality. Dr. Mallett is certainly a " find." There " has achieved its success because of its Mr. Watson Watt, like nearly all the com- is not a spark of pomposity about him.He name." mittee of the Wireless Section, is a "govern- is so diffident that he disarms one.His No ;by any other name it would sound as sweet. ment " man. He comes into the thousand apparently easy-going manner is almost * * * a year class of Civil Servant-which is really embarrassing.But his insight and shafts the most you can earn in radio under a safe of criticism are no whit the less sharp.He A Radio Marriage but stingy Civil Service. is the ideal man for the Woolwich Poly- Odd how nearly all the peculiar events If you possess a first-class honours degree technic.He so obviously knows the needs occur in America.If a hen is born with ten in electrical engineering and have had a few of industry and obviously has little patience heads its birth -place is sure to be Ohio.If years brilliant record in commercial radio with academic narrowness.He is a rebel a dog can work a radio set with its tail it and are clean and honest, is almost certain to hail you may pass muster for * from Connecticut. one or other of the very I now read that a Miss few radio jobs offered by PRAISE FROM "P.W." READERS Grid has married a Mr. theCivilService,say, Your "Armchair" notes, which I enjoy ments with greatinterest.-JAMES FORBES, Tube in New York and under the Admiralty, the much.-E.very J. HEWING, 245,Stone Road, 6, Iron Cliffe, Apethorne, Hyde, Cheshire. what's more they keep a Staffor * Air Force or-very rarely * * * Once again I have the pleasure of looking radio shop.Mrs. Grid- -the Army. And for this I am a regular reader and enjoy "From forward to reading " From My Armchair.', the bride's mother-said you will be offered £5 per My Armchair."-A.W. BROWNWELL, -M.E. DENTER,93,RobertsonStreet, on being told of the en- Fieldhead, Carleton, Penrith, Cumberland. Silverthorne Road, Battersea, S.W.8. week or occasionally £6. * gagement :" Anode they Of course there are annual * Have just finished reading with enjoyment would." How awful ! increments of, say, £18. One final tribute.I thoroughly enjoy your soy usual monthly " pick-me-up "-to wit, However, similar things " Armchair" articles. You might also add your "ArmchairArticle.-H. J.DAVIES, But don't imagine you "Humorist" to your many accomplish- 85, Main Street, Cadoxton, Barry, Glam. happen in London, Eng. will ultimately become an ments. You have brought me many a laugh I knew of a Mr. Fish who You have a rare gift* for writing and your which the B.B.C." wisecrackers " have often Admiral, an Air Marshal failed to do. More power to your elbow !- Armchair" Notes give me much pl e. married a Miss Bole, and or a General.You will W.PEARSON, 168, Eltham Road, West Bridg- -W. POVER. now they sell ants' eggs ford, Nottingham. wear flannel bags all your Imust say ,your talks from " The Arm- in Wimbledon. life and may rise to the chair"are' It."-V.R. TREADAWAY, * * * position of Mr. Watson I have followed your " Armchair" instal. 36, Ham Road, E. Worthing. How many have noticed Watt.But as there are* * a " slip " which has often only two or three of his been perpetrated by the eminence you will have to be very able- and rather enjoys the role of enfant terrible. B.B.C. ? Thelastthingsaid by the as he is-and, as he looks very well and He is completely free of flies.The radio announcer is:We are closing down now full of energy, wait a long time. industry will do well to keep in very close till to -morrow. These reflections are suggested by Dr. touch with this new prophet or, rather, old As to -morrow has the meaning of " next Mallett, who talked in his inaugural address prophet with new robes of office.He is the day after this," the announcement is wrong about the right training for a radio engineer believer in knowledge for what itdoes because it is already " to -morrow " when and gave us the idea 6that he thought the rather than knowledge for its own sake. the announcement is made-immediately " Services " got the best men. More power to his tongue and chalk. after Big Ben's turn. Radio engineers in commercial firms will Principal Mallett was and is immensely A niggling pedantic quibble, but the dispute this.They will say that men who popular amongst his students, partly for B.B.C. are such sticklers themselves. take £5 or £6 per week are really raw his personality and partly because he is a * * * material-perhapsbrilliant raw material brilliantteacher. He issureof equal I heard these on the radio.I actually but nevertheless without solid achievement. popularity at the I.E.E.While at the City laughed. They will point out that men who have and Guilds a student during the Rouse A ;I'm keeping hens as a hobby. proved themselves are never desired as new murder case pinned to his blackboard an B :Do they lay many eggs ? entrants.They like them young and good Evening News poster Which read :HAIRS A :They could do, but they don't need and cheap. FOUND ON MALLET. Needless to say, he to in our position. By the way, if you apply for one of these enjoyed the grim joke with the rest of them. * * * poSts you will probably be asked :" Why (Continued overleaf.) 424 Popular Wireless, December 26th, 1936. FROM MY ARMCHAIR-Continued * RADIO'S ARCTIC AID A :The fire in London was so big it The latest I read is that a man was fined could be seen by the Beachy Head light- ten shillings at East Grinstead for hitting * house keeper. his wife (alleged by him to be prone to B: Go on ? nagging) on the head with a wireless book. CANADA'SSignal Corps has been busy C: Yes, he was in London on holiday. recently, not with war preparations, I only hope it was my Book of Practical but with modernisation of the com- Radio. munication system along the Mackenzie He travelled a great deal and always * * took his wife with him so that he wouldn't River.Equipment is being rushed in and have to kiss her good-bye. " Hertz gave us wireless waves but give assembled to give growing airway services * * * me the S.T.800," says "a reader.Thanks in the sub -Arctic and Arctic the latest in "Sri Clean and Wholesome" very much. airplane to ground communication. * * This last almost verges on sex and sex " The service to be given to aviation religion and politics are rightly banned in " I want," says A. L. B. of Bodmiii, " a interests," says National Defence Deputy this journal.Which reminds me that re- set which will give me every wavelength Minister, L. R. La Fleche, " is an extension cently I had a letter from a doting mother from 30 centimetres to 20,000 metres- of the present service in providing weather who, referring to the Manual of Modern with television, of course. It should cost reports to pilots at all stations.The new Radio, wrote: "I am so pleased my boy not more than £10." equipment will enable these and other enjoys your books. They are always so Try the next counter. information to be given to radio -equipped clean and wholesome." * aircraft in flight, by voice." Believe me, it is an art to keep a wireless " How much longer " (what memories of A start was made on the modernisation textbook clean and wholesome.I pride Cicero that conjures up !),writes Alfred programme last year when Diesel engines inyself that I do not have to resort to any- Diggle Butterworth of Southend, " are we were shipped to Mayo, Yukon, and Fort thing questionable to raise the Norman ontheMackenzie sales of these books. You may River, and Port Smith on the recall the grave scandal over "WHY CALL US VIEWERS ? " SlaveRiver,bothinthe Professor Hesslig's " Textbook North-west Territories. A more of Electrical Dynamics."I powerful transmitter was refer to that bit about applying placed at Fort Smith to keep Schnubber and Giebe's formula in contact with the new Signal tothe determination of the Corps transmitting station at viscosity boundary conditions Edmonton, where the bulk of for piezo-electric strains along the traffic for the Far North the third axis of polarization. leaves the telegraph lines to Not at all wholesome, never continue by radio. mind clean.No one was sur- prised when the book was with- New Stations drawn as a result of action This year similar plants have taken on information received. been installed at McMurray at * * * the end of the railway in northernAlberta, Chipwyan Why " viewers " ?This is onLakeAthabasca,Fort what we are called when we R esolutionon GreatSlave watch, paralysed, the television Lake, Fort Rae at the top of programmes. " Good evening, Great Slave Lake, Cameron viewers." Do you like it ? Bay on Great Bear Lake, and suppose it is very hard to find " Whyviewers ' PThis is what we are called when we watch, paralysed, the Goldfields on Lake Athabasca. a proper word. Butisit television programmes. .. ." says John Scott -Taggart.Whatever name is given All these points are on the necessary forthe charming to those who look -in to television there is certainly no lack of enthusiasm at the demonstrations of commercial television sets in the London area.The set seen airway to the mining regions young ladies to call us any- in this photograph is the Pye " Teleceiver." east of the Mackenzie River thing ?On the common or which have been opened by garden radio we are not vocatively called to put up with your egotistical abuse and airplane since 1930.Air traffic is heavy listeners."They don't say " Good even- conceited megalomania ? " into these formerly remote areas, and new ing, listeners."They probably feellike Well, certainly for another year. mines are going into production annually. saying " youse guys," but they just call The move to give modern communication us nothing or " everyone." * * * is in line with other Government aids to What's wrong with the idea of ringing " More Power to Your Vitriol ! " new mining developments, the changes while we watch enraptured by " What joy," says G. M. of Stockport, The stations being equipped all have pictures of village signs or pieces of pottery. " to read your articlelashing into the Diesel engines as against petrol engines I suggest gazers, peerers, peepers, or gorps. jargon -mouthing short-wave ham brigade formerly used extensively.The latest in Critics at television demonstrations would whose puerile boasting with theirsilly radiophone transmitters with facilities for be disarmed from the startif Miss Bligh radio cigarette cards, as you call them, has changing to three or four frequencies are said: "Good evening, you stiff - necked, nauseated every sober citizen for years. No being installed. mean - mindedlittlecarping gorps ! " one minds the genuine short-wave experi- Salutary, but would it be genteel ? menter, 'but the mean -minded little squirts Value Already Proved * * * who have crowed over the broadcast listener While no radio -equipped aircraft fly as The Most Exciting Place for so long deserve every word you say. yet on the Arctic air services except during More power to your vitriol.Pour it over Readers of my notes will know that I special searches for lostfliers, now that them. radiophone serviceis available, airplanes regard East Grinstead as the most exciting No, it's too near Christmas. place in England.It is only rivalled by will be equipped, allowing the ships to Pontypridd-which is,or was, in Wales. * * * remain in constant communication with Everything under the sun has happened or " When," asks F. L. of Durham, " will their northern bases, will happen in these two places. Open your you give us a television design complete The radiophones at Rae and Goldfields newspaper casually at any time and you with 50 valves and 30 knobs ? Your public have already proved ofvalue, Deputy willfind something about a man with needs it." Minister La Fleche points 'out, in providing staring eyes, an electrocution, a thrilling I shall discuss the matter with Jeff, my communication with outlying settlements. football match, a golfing scandal, a Cabinet radio mongoose, who assists me inall There are a few fishing stations and trading Minister's visit, or a wireless licence drive television work, posts in the district as well as a growing occurring there. J. S. -T. number of new mines. J. M. Popular Wireless, December 26th, 1936. 425 TELEVISION TOPICS Collected by A. S.Clark * A weekly feature which will keep the reader au fait with all the latest news and developments in television science.Itwill appeal aliketothe newcomer to television and the advanced experimenter

THE NUMBER 21 -inch porcelain insulating shafts, and deal OF PARTS with any 1 inch diameter spindles. Illustration of the * tremendous need FIRST TRANSATLANTIC TELEVIECN for simplification Recent talk about receiving television in television across the Atlantic brings to mind that this apparatus is was first accomplished in 1928. provided by On February 9th of that year the famous figures to hand of John Logie Baird succeeded in receiving thenumberof television sent by one of his own engineers parts in one who specially went over therefor the The three announcers at the Berlin Television Station.From left to right standard 23 -valve they are Joachim Richert, Herr Junkers and Waldemar Bublitz. purpose. receiveronthe * * * market. The number is given as3,980. And IN AMERICA remember, each one will have at least two Threehundredpressrepresentatives " TELEFRAMES " connections ! recently saw a demonstration of television Items of General Interest * * * in America.The latest developments of N.B.C. television were shown to them on a SPONTANEITY WELCOME row of twenty television receivers which AMINIATURE dance band specially The difficultyofprovidingrepeated were operated by transmissions from the for television has been formed by rehearsalsfortelevision programmesis Empire State Building. Mr.Wild,the trumpeterinthe likely to show up hi a good light those Pictures 6" by 8" and 16" by 8" were televisionorchestra. He and some of artists whose items are largely based on shown, and both reflected and direct view- his colleagues have formed a small rhythm spontaneous acting and ideas.This is all ing was utilised.The results were con- section called " Eric Wild and his Tea - to the good, for spontaneity is the real sidered amply satisfactory to be accepted Timers." thing, and that is what television is going in the home as a television service. It is certainly a bright idea because, due to thrive on. totheir small number, the performers Once again we can repeat that " actu- should come over well enough for interest ality " is the salt of television. to attach to watching them play at their * * * TELEVISION various instruments. HIGH -VOLTAGE INSULATION * * * Those who wish to make doubly sure DE LUXE MIRRORS FOR TELEVISION about the safety of handling potentiometer It is most important that mirrors used controls and suchlike which deal with high WE recently witnessed a demonstration in the lids of television receivers should voltages,shouldexaminetheBulgin of televisionatthe Teddington be of excellent quality to avoid light loss flexible shaft couplings. premises of the new company of and distortion.But even the 'bestof These are obtainable with 1 -inch and Bosch Hall, Ltd.We understand that plate -glassmirrorsisliable this firm proposes to specialise to give a slight double image * *.inthedeluxetelevision effect due to some reflection market and to aim at pro- from the front surface of the ducingtheRolls Royce cf glass. Thiscanbemost TELEVISION AT CHRISTMAS television apparatus. noticeable on captions to films The chef of a famous Strand restaurant will inaugurate the Even with the average price and similar items. Christmas afternoon festivities at the London Television Station of television receivers at around One way to avoid thisis by carving a prize turkey before the camera.The programme £100 there are those prepared to silver the glass on the front will also present the fourteenth and Christmas edition of " Picture Page," Cecil Madden's topical television magazine, and it is ex- to pay considerably more to surface.This is the method pected that many of those interesting people who come into the have the" best money can adopted in a type of mirror limelight only at Christmas -time will take part.During the afternoon Edward Shackleton, son of the famous Antarctic explorer, buy." Afterall,thereis which we understand the Edi- is to give his own account of a lonely Christmas spent on Ellesmere quite a large trade done in swan Company will probably Land.Films actually taken amid the ice and snow will be trans- ordinaryradiogramscosting be handling as a standard line. mitted during the talk, and Mr. Shackleton will show the fur clothes * that he wore, his Christmas frying -pan, and an assortment of £1C0 and up.We feel that * * strange implements which gave the only touch of civilisation to this firm should be on quite a BATTERY HIGH-TENSION the experience. geed The possibility of those with- A Christmas party of celebrities enjoying themselves before the television camera will be a high spot in the evening transmission. At the same time, we are out access to mains obtaining Cecil Lewis will act as Meister of the Ceremonies.The evening satisfactory television results is programme begins with carols by the Singing Boys from St. informed, theywillbe pro- greatly enhanced by the new Mary -of -the -Angels Song School, the president of which is the ducingtelevisionunits and Rev. Desmond Morse -Boycott.Then will follow a film pro- kitssuitableforthe home Bulgin Vibrator. gramme, " Christmas Through the Empire," which is being By interrupting current from specially prepared fortelevision.Film sequences have been constructor.Although carry- secured dealing with Christmas in practically all parts of the ingtheirtame,theseare an accumulator, this enables a Empire.There will be glimpses of football in Fiji, a Christmas voltage of two or three thousand dance in Basutoland, ski-ing in Canada, the Khyber Pass in expected to be handled en- to be obtained.This is recti- winter, and " shots " from Australia, Gibraltar and the West tirely by a separate organ- fied by a valve. Indies. isation. During the evening Commander A. B. Campbell, who is one of Thelistnumberof this television'sfirst" causeurs," or talkers,will describe some When theseunits are in high -voltage vibrator unit is unusual Christmases. fullproduction we hope to H.T.V.2. It works witha be able to give a test report D.C. input of six volts. * from personal experience. .126 Popular Wireless, December 26th, 1936.

out. We now have two frames and two TELEVISION TOPICS-Continued primary scans interlaced. Together these two primary scans form a secondary scan.The next step now is to We now carry out the second frame, perform another secondary scan slightly which is an interlaced primary scan, and displaced to the side of the first.This deals MULTI -MESH deals with lines 4, 10 and 16.Cross these with lines 2, 8, 14 (making three frames in all), and then with lines 5, 11 and 17 inter- SCANNING AN EARLY RECEIVER laced with 2, 8 and 14, as in the first case. We now have four frames. A third secondary scan deals with lines LAST week, under the feature " Seen in 3, 9 and 15, following on with 6, 12 and 18. the Air," some details of the Baird Making six frames in all with six primary large -screen system of television were scans and three secondary. given.In view of the fact that-we under- In the system demonstrated the other stand-demonstrations of the system may day there were 161 pictures per second. soon be made to the public during pro- Butsinceeachpicturecontainedsix grammes at the Dominion Theatre, an frames, there were 100 frames per second. explanation of the unusual form of scanning From this it will be appreciated why employed will be of interest. flicker due to scanning was absent. Another Although quite simple in itself, it is not advantage of this is that the circuits con- exactly an easy one to describe.. However, cerned in the apparatus may have a much the following should make it quite clear, higher low -frequency cut off. and if not indicating preciselyallthe details involved, it nevertheless explains Increasing the Light the principle in general. Reverting to our dots again, it will be The First Point seen that when the first secondary scan is The sequence in which the lines making complete (lines 1, 4, 7, 10, 13 and 16 crossed up the picture are scanned is the first point out) one-third of the picture is covered by to consider.To get an idea of their order lines equally distant.By widening out the you are asked to make 18 dots in a row on spot at the receiving end so that line 4 just a piece of paper and to number them 1 to 18 meets the edge of line 7 and so on, a great in order. increase in light on the picture may be These represent the lines to be scanned obtained with but little loss in definition. and they are crossed through as we deal This spreading, of course, applies to all with them.Cross numbers 1, 7 and 13 secondary scans.By altering the number through. of interlacings per secondary scan, and the This. could be carried on for the 120 lines number of secondary scans, the number of which there are to each picture, but 18 lines and frames per picture can be varied. suffice for illustrative purpose. Having The system is adaptable to both mechani- crossed out every sixth line we have com- cal and electronic methods. Mechanical pleted one frame (a frame of spaced lines scanning by means of a mirror drum and One of the first complete high -definition television with gaps in between).This is termed a receivers ever made.It was built by the " P. W." slotted disc was used at the recent demon- primary scan. Research Staff about two years ago. stration.

modulating wave having the samepicture is altered by altering the shape as the original envelope of point of bias at which the tube is TELEVISION FOR BEGINNERS the carrier. operated.If we have too little The characteristic of the tube isbias the screen is bright even with G. Stevens explains how the signal is applied to the tube the same as that of an ordinarythe lowest value of modulating valve, except that we plot thesignal and there will be no black relation between brightness of thetones at alL THE first figure in this article This " envelope," as it is called. screen and voltage applied to the shows the television signalis amplified by the first valves of grid instead of anode current and THE corresponding to a singlethe receiver and then rectified by voltage applied to the grid.This line of a Baird transmission. The the detector before being applied'curve is like the one shown at the TUBE'S line through the centre of the to the tube.For the moment we top of the diagram-as the bias shadedarea marked 0isthe of the grid is increased the bright- CURVE zero line, and the line marked ness of the line diminishes until at THE WAVEFORM the bend of the curve the spot goes 100 per cent shows the maximum too height that the carrier wave would out altogether. reachifthebrightestpossible Bias Adjustment picture were being transmitted. Having connected the output Never Below 40 Per Cent from the receiver to the grid Fig. 2. You will note that the " hills circuit of the tube we adjust the Howthe and dales "ofthe modulation bias until the screen is just dark- tube provides never drop below 40 per cent of that is at the bend of the curve black the carrier amplitude, except at where the dotted line cuts it. Now MODULAtION and the beginning and end of the line, if we consider the effect of the white signal on the bias we see that any parts of when the carrier itself drops to the zero and there is a pause.The variation in voltage to the right picture. figures, by the way, give you an of the dotted line alters the grid idea of the relative time taken fcr bias and increases the brightness ONE LINE IMPULSE of the tube to correspond. this pause and the time taken for Fig. 1.Showing the signal for a one complete line.They are in single line of a Baird transmission. The synchronising signals, on The effect will be rather like an millionths of a second ! the other hand, are all to the leftunder exposed print-greys and In one complete picture there can suppose that the receiver is aof the dotted line, and will onlywhites, but no contrast.On the are 240 of these signals following straight one, as a superhet is tooincrease the bias in a negativeother hand, if the bias is set too each other with a break in between, complicated to consider at the direction. They willtherefore high an appreciable value of signal and then comes a longer pause, present moment.After passing only increase the " blackness " ofwill be required to bring the curve correspondingtothepicture through the detector the signal the screen and will not affect theup the bend, and the picture will synchronisingpulsebeforethe appears as the sketch of Fig. 2, the variations in the picture. You will suffer from an excess of black, sequence starts again. carrier being removed and the also note that the quality of the giving heavy shadows. Popular Wireless, December 26th, 1936. 427 MY TELEVISION ADVENTURES By HELEN McKAY

SUPPOSE you were getting on quietly realise that until the technical people can with your work when the 'phone rang settle on just one television system, instead and a voice said, " This is the B.B.C." of broadcasting on two main systems in -then went on to suggest that you should many different ways, it's going to be tough throw up work at almost an hour's notice work for a television star. and accept a B.B.C. contract for television. Make-up, and even presentation of your What would you do ? act, has to take into account the system That happened to me only a little while being used. before the opening of public television tests There was aclausein my contract in time for the last Radio Exhibition. specifying certain dresses I was to wear- I was flabbergasted.Television meant not because the Corporation was fussy almost nothing to me, apart from what I about my wearing low backs, but because of had read in the papers and magazines. the make-up difficulty. White was- the Friends of mine at the B.B.C. had told me colour they wanted me to specialisein, about the apparatus and new studios being and as my mother is a fashion designer I fitted out at Alexandra Palace ; but if ever got her rapidly to scheme out some new I gave it a thought at all it was probably dresses for my television debut. The Authoress of this article. only just that maybe inlateryearsI Then, when I met Mr. D. H. Munro Television taught me that the B.B.C. should be able to add television to my string (television production manager), Mr. Leslie can be a very efficient place, and can knock of vocal conquests. Mitchell, the announcer, and other B.B.C., spotsoff a filmstudioforproduction Baird, Marconi-E.M.I. officials, we started technique. A Thrilling Opportunity work. All the staff wear sand -colour coats, which Well, I set the 'phone down with serious Make-up tests came first-and I had a givethem aserious,technicalair. I. misgivings.The B.B.C. had offered me a shock. enjoyed every minute of those rush days wonderfulchance-butIdidn'tknow just before television started, and knowing whether or not to take it. something of the slackness in production It was a thrilling opportunity to be in at of many cabaret, stage and theatrical shows, the start of a new thing-just as I was in at One of the first stars to be I think Mr. Munro and his staff deserve full the start of colour films.In fact, I was in given a contract for television, marks. the very first colour picture made in this I have learned from televising that a country. Miss McKay describes in a " look -and -see " artist will have to get used Films I have shelved in the past two or vivid manner her impressions to having every shade of his or her per- three years as I am not yet satisfied that my sonality revealed when televising. features are filmic.I had a minor accident and experiences during her In the spotlight studio only head and to the bridge of my nose, through an un- first broadcast at Alexandra shoulders (or three-quarter length, at the fortunate fall in the studio a few years ago. Palace. most) come into view. 1 keep meaning to go to a surgeon and You sit facing the flickering light, and have that bridge straightened out so that you, in semi -darkness, are apt to forget I look " photogenic " enough to satisfy the that at the distant end thousands of people keenest film producer. But rather naturally I knew all about film make-up (which is can see your every movement, just like a I keep putting off the fatal date for what not the heavy ochre previously used in film close-up. In fact, it's much worse than may be a- painful process-and I have so silent -film days), but when I first saw myself a film close-up, because a producer can much work to do that a film career must made up for the Baird spotlight system I " shoot " you time and time again until wait awhile. nearly fell through the floor. you don't flicker an eyelid. But the B.B.C. said it didn't matter about My face had to be slightly whitened, my my nose, or the fact that I have red hair lips made blue and my eyebrows touched More Rehearsals are Necessary (despite what I'd read somewhere about red up. They were a bit doubtful about my red But once televised-well,all mistakes heads being unsuitedto thetelevision hair for the spotlight system, but after have to go through.With the Baird film camera) ;they just wanted me to sign the a few tests and squinting at me through system there is a short time lag, and in a contract. 'coloured lenses they were satisfied. special programme they could, I suppose, As you know, I did.I rehearsed with But, though O.K. on the television, I rush the film through again. So there is an Henry Bronkhurst, the B.B.C. Television looked a sight in the Alexandra Palace advantage here, so far as the television Orchestra, the " Three Admirals," and so studio, with blue lips, white face and red artist is concerned-and all that the listener on.Two hectic days were spent in final hair ! and looker -in lose is about a minute's lag, rehearsals, and then one morning, feeling Thefirstbroadcast (ontheopening between the making of the film and the very frightened about it all, I crept up to Wednesday of Radiolympia) had to be done actual television projection. the televisionlensafterLeslie Mitchell with this make-up, but I became used to it I can see that television will revolution- had announced me-and sang my first after a few days, and learned that people ise the way B.B.C. shows are produced, and television song. wouldn't scream and run at the sight of me much bigger studios will be needed. in the corridors. There'll have to be many more rehearsals, Prom the Broadcaster's End For the Baird film system the make-up too, and artists will have to work harder. You probablyknowallaboutthe is rather like present talkie " make-up, There'll be no more reading from scripts. listeners' end of it-what setscost, the but just a little more accentuated. I had to stay up late rehearsing my special short waves on which the programmes The Marconi-E.M.I. system, which was special numbers.If I'd just been broad- are broadcast, the queer -looking cathode- used on alternate days during my second casting without television I need not have ray tubes on which the image appears as week of televising, doesn't need any special had the, lyrics word-perfect. though by magic. make-up. . In the spotlight studio Leslie Mitchell put So may I tell you about it all from the Friends who saw me televise tell me that I over his announcements at intervals and broadcaster's end ?I've had years of ex- looked worst on the spotlight system, but then slid sideways (there's hardly an inch to perience in variety, cabaret, films and radio. they were all so thrilled at seeing television spare) so that I could squeeze in front of the But television has taught me some things pictures for the first time that they didn't - lens.Rather like the early cinemas. Ididn't knowbefore.'It'smade me bother to be too critical, (Please turn to page 444.) 42.S Popular Wireless, December 26th, 1936. LEARNING FRENCH THROUGH YOUR RADIO This week we present Part 42 of the popular language series contributed exclusively to "PW." By S. C. GILLARD, M.A.

THIS week I want to talk about the 11 fait toujours quelque sottise He always does something foolish. INDEFINITE ADJECTIVES AND Quelquefois je me couche a. huit heures PRONOUNS. Adjectives, you re- Sometimes I go to bed at 8 p.m. member, MUST have a noun alongside. QUELQU'UN (some one) is a pronoun Pronouns stand INSTEAD of nouns. Iwith both a FEMININE and PLURAL must add a word of warning here, forform. English isn't very helpful in this respect. Singular English contains a number of words which Fein. are both ADJECTIVE and PRONOUN. QUELQU'UN QUELQU'UNE The only way to distinguish these is to Plural understand the function of each in the Masc. Fem. Stephen Williams, chief English announcer at Radio Luxembourg, in cheery mood before the sentence.Let me give you an illustration. QUELQUES-UNS QUELQUES-UNES " mike." Take the two sentences : Quelqu'un a frappe a la porte Someone has knocked at the door. On vous a vu ce matinYou were seen this morning. SOME BOYS LIKE MUSIC Quelqu'une a dechire It journal On ne peut pas faire ca, n'est-ce pas ? SOME OF THE BOYS LIKE 'MUSIC. Someone (f.) has torn the newspaper. You can't do that.Eh ? Quelques-uns de mes clients sont francais It is the two words " some " that I want Some of my clients are French. The portion of the BULLETIN COM- you to consider.They are sp#It alike. Quelques-unes de ses aventures etaient remarquables MERCIAL for this week is a short one. Hence it is only reasonable to assume that Some of her adventures were remarkable. It is : they are one and the same word. This isn't Another important ADJECTIVE and VIA NDES (meat)Arrivages 360,000 kilos. PRONOUN is TOUT.Study the several Bceuf Beef so, however.The first" some "is an Quartier de derriere Rump 6 a 9 ADJECTIVE, becauseithas the nounphrases below sothat you completely Quartier de devant Fore -quarter2.50 a 4.50 " boys "immediatelyalongside. The understand the use of this word. Aloyau . . Paleron Shoulder 3.50 a 6 second " some " is a PRONOUN because When an ADJECTIVE, this word TOUT Bavette Top of sirloin 3.50 a 6 it HASN'T a noun alongside.In Frenchhas the usual four forms-TOUT, TOUTE, Plates -cotes Rib of beef 2.50 a. 5 these two" sores "are DIFFERENT TOUS, TOUTES. As a PRONOUN it has Collier Neck 3 a 5 WORDS. two forms only -,--namely, TOUT, TOUS. And this suggests that you ought to know As you learn the INDEFINITE ADJEC- First as an ADJECTIVE. the different Meat items of the menu card. TIVES AND PRONOUNS which I am Tout homme, toute femme Every man, every woman. Du Bouillon (boo-yo(ng)) Broth Tous les tonnes de ce probleme Du Potage (pot-ahsh) Soup going to give you now, do realise the need All the terms of this problem. De la Soupe (soop) Soup there is to distinguish ADJECTIVE from Sous tous ses aspects Under all its aspects. Du Consomme (ko(ng)-som-eh)Gravy Soup Tout cabinet de coalition Every coalition cabinet. De la Soupe grasse (soop grahss) Meat Soup PRONOUN. Suspension de tout paiement des dettes De Ia Soupe maigre (soop mehgr) Vegetable Soup First of all, then, the adjective CHAQUE Suspension of all payment of the debts. Du Roti (roh-tee) Roast Meat and the corresponding pronoun CHACUN. Toute sa force primitive All his primitive strength. Du Bouilli (boo'yee) Par tous les moyens By every means. Un Ragout (rah -goo) A Stew Both mean EACH, but with a difference. Tous les jours Every day. Du Hachis (ah-shee) Hash CHAQUE (each,every), the adjective, Tous les deux jours Every other day. Du Bo of (be(r)f) Beef Tout le Reich The whole Reich. Un Bifteck (bif-tek) A Beef -steak MUST be used with a noun.It has no A la grande surprise de tout le monde Une Culotte de Bceuf (kh-lot) A Rump of Beef FEMININE or PLURAL form-e.g.:, To the great surprise of everyone. Un Aloyau (al-wah-yoh) A Sirloin of Beef Chaque jourEach day. Tout calcul, toute combinaison Du Veau (voh) Veal A chaque jour suffit sa peine Every calculation, every combination. Une Tete de Veau (teht) A Calf's Head Sufficient unto the day is the evil thereof. Then as a PRONOUN. Une Longe de Veau (lo(ng)sh) A Loin of Veal Chaque instrument est valable Une Rouelle de Veau (roo-el) A Fillet of Veal Every instrument is valuable. Le probleme est par dessus tout un probleme psycho- Un Ris de Veau (ree) Sweetbread Chaque raison a cinq etages logique Un Jarret de Veau (shah-reh) A Knuckle of Veal Each house has five stories. The problem is, above all, a psychological problem. Une Fricassee (frik-ah-seh) A Fricassee Tout devient fluide et instable Un Fricandeau (frik-ah(n)-doh)Stewed Larded Veal CHACUN (each one, every one) is a pro- Everything becomes fluid and unstable. Du Mouton (moo-to(ng)) Mutton noun, and so requires no noun alongside. Tout est fini Everything is over. Des COtelettes (kot-let) Mutton -chops Elle desire tout voir She wishes to see everything. Un Gigot (she-goh) A Leg of Mutton N.B.-CHACUN has no PLURAL, but it Its mangeaient tous They were all eating. De Ia Poitrine (pwah-treen) Breast of Mutton has a FEMININE form " CHACUNE." Un Collet (kol-leh) Neck of Mutton One more INDEFINITE PRONOUN Une Epaule (eh -poi) Shoulder of Mutton Chacun de tries freres est un architecte will complete the quota for this week. This De l'Agneau (an-yoh) Lamb Each of my brothers is an architect. Un Quartier de l'Agneau A Quarter of Lamb Chacune de mes sours est une modiste is the important little word " ON."It is (kar-tyeh) Each of my sisters is a milliner. equivalent to the English " one," as in- Du Pore(per) Pork Chacun des ces programmes est long Du Lard (lar) Bacon Each of these programmes is long. One gets terribly tired standing about. We Du Jambon (shah(m)-bo(ng)) Ham Chacune de ces lectures etait interessante tend to avoid this indefinite word " one," Des Saucisses (soh-seess) Sausages Each of these readings was interesting. Un Cervelas (sairv-lah) A Saveloy whereas the Frenchman works it to death. Des Tripes (treep) Tripe If you understand the difference between For instance, he much prefers it to the De la Venaison (ven-eh-zo(ng)) Venison CHAQUE and CHACUN you ought to see PASSIVE, and instead of saying " / was Du Gibier (she-byeh) Game a similar difference between : Une Poularde (poo-lard) A fat Pullet toldlastnightthat. ."he will say Une Cuisse (kweess) A Leg QUELQUE and QUELQU'UN " ONE told nee last night....""On me Une Aile (el) A Wing Le Foie (fwah) Liver QUELQUE (some, a few) is an adjective dit hier soir..." De la Volaille (vol-afee) Poultry tnd is used with a noun.Its FEMININE Here are some phrases to study. Cjaursc a( sshs eio( kar-kass) The Carcass form is the same, but it adds " s " for the On sonne, -On frappe DuLa Gravy Some one is ringing, some one is knocking. Un Pate (pah-teh) A Pie PLURAL. Madame, on vous demande [This series commenced in the February 1st issue J'ai recu quelques invitations Madam, some one is asking for you. of " Popular Wireless."Those who require back I have received some invitations. On declare que .. .. They say that... . numbers should apply to The Amalgamated Press, Le braconnier a attrape quelques lapins A -t -on ferme les fenetres ? Ltd., Back Number Dept., Bear Alley, Farringdon The poacher has caught a few rabbits. Have they closed the windows? Street, London, E.C.4.-ED.] Popular Wireless, December 26th, 1936. 429

"HULLO, LONDON." A chat about commercial radio. By W. L. S.

I AM occasionally taxed by readers with listener by introducing a new " hazard," Most of the ships equipped for 'phone work saying a lot about short-wave broad- in the form of a carrier -wave which was not do not carry " unscrambling " apparatus, casts and short-waveamateurs,but constant in frequency. The modulation was and conversations between Rugby and leaving the commercials out of the picture. still scrambled, but, in addition, the carrier the " Queen Mary," " Empress of Britain," Probably this is a just criticism. Admittedly was " wobbled," so that it became a matter " Monarch of Bermuda," " Bremen " and the commercials deserve a little publicity of superhuman skill to wobble the dial " Europa " may be picked up on one or sometimes-not that they want it !-but, of the receiver and to keep the beat at other of the shipping channels,if you from theirvery nature, they areless 3,000 cycles. happen to be lucky.These transmissions interesting to the ordinary listener than the And that is the reason for the number of are not made very frequently.Sometimes, other two classes of transmission. carrier -waves which make you think that I am told, there are only a few calls in a A commercial station is one which handles the transmitting aerial is swinging in the week.But the fact remains that I receive traffic for business purposes.This traffic worst gale that ever was !You will come a lot of letters fromreaders who have may be a series of confidential been listening to conversations personal messages exchanged be- between ship and shore.They tween London and Tokyo ; it may A MODERN SHIP INSTALLATION are not allowed, by the terms of be news from the Spanish corre- theirlicences,todivulgethe spondent of an American news- natureofsuchconversations, paper in Madrid ;or it may be and, even if they transgress and Press messages of a broadcast tell ma, I am absolutely forbidden nature, which, however, are sent from quoting them in print. out in Morse. An increasing number of Test Transmissions commercial stationsarebeing Allthese Hullo, London " equippedfortelephony,how- and " Hullo,Rugby" calls, ever, and one may often hear, in however, arc not of a private the course of a casual " listen - nature. One often hears an round," some quite interesting Americanstationtestingout transmissions. undertheinstructionsofits technical operators, and improv- " Scrambled " Telephony ing the strength and quality of As every short-wave listener transmissions, in much the same knows, the Transatlantictele- way as one amateur station does phone is " scrambled."It used with the help of another. to be broadcast in its normal Many a time have I chuckled at form,sothatanyonecould little scraps of informal conversa- overhear privateconversations. tion between operators at Rugby Admittedly a beam was used at The Marconi wireless telegraphy apparatus on the " Empress of Britain." and their " opposite numbers " either end, but this did not stop in America.It is impossible to a large number of people from breaking acrossthemallovertheshort-wave tell you where to listen if you want to hear in." spectrum, and that wobble is just there to this sort of thing going on, because, as far Then, with the progress of short-wave stop you from hearing things that you as I can see, you are liable to pick it up on listeningasahobby,theauthorities aren't meant to hear.In other words, you, any wavelength between 12 and 80 metres. realised that something would have to as a short-wave listener, have cost the On the shipping bands, in the regions of be done, and they began to " scramble " commercial concerns quite a lot of money. 24, 36 and 6'3 metres, you will sometimes thespeech,renderingitunintelligible A cheering thought in a way ;it makes hear the shore stations testing with one during its journey through the ether, at the usrealisethat we arepeopletobe another or with the ships ; 13n you will hear end of which it was unscrambled and put reckoned with ! one of Rugby's vast array of transmitters into its right shape again. Fortunately for the listener, however, on all sorts of wavelengths. Variouslisteners who were" inthe many of the transatlantic 'phone trans- The transatlantic " ocean greyhounds " know " then discovered that all that was mitters handle " plain language "some- are never out of touch with either end of necessarytoenable them toturn the times.On occasions when they are merely theirroute. The" Queen Mary "for unintelligible noises into clear speech was a relayingfrom one continent to another instance, can work with New York and 3,000 -cycle beat -note.The few people who somethingthatisintendedtobethe Canada while she is still in Southampton owned stable short-wave receivers found subject of a general broadcast, there is no Water. Thosefortunateshort-wave that they only had to oscillate on the trans- need for secrecy.You will often hear the listeners who can read Morse will find that mission, with their set so adjusted that a RockyPoint(U.S.A.)stationstesting they can pick up signals from ships in all 3,000 -cycle heterodyne beat was generated, ordinary speech on their various wave- sorts of queer spots. They need a list of call; and there was thespeech,neatlyun- lengths,and sometimestheyputout signs, of course, unless something in the scrambled for them. gramophone records, or relay a broadcast text of the message willhelp them to Shortlyafterthisdiscoverybecame programme, just for test purposes. identify the ships they are listening to. uncomfortably well known, most of the Ship -to -shore telephony, too,is under- There are other commercial services that importanttransatlantic'phonestations standable by the ordinary listener, although are interesting, but my space is gone, and made thingsimpossibleforthecasual he's not really 'supposed to listen toit. I must leave them till another time. Popular Wireless, December 26th, 1936.

ON THE SHORT WAVES-Page 2. althoughcertainwavelengthswillbe " blocked out " from time to time.Any- way, he'll get more with a short-wave set than he would without one ! K.. (Leeds) sends in a beautiful log of stations heard on his 18 -valve' isuperhet. He also wants to join a club in the neigh- bourhood of Teeils, if there is one ;and W. L. S.RepliestoCorrespondents if anyone in the vicinity would like to look him up, he will be pleased to see them. M. (Stellenbosch,South Africa) SPACE will not permit of long answers Full address :Mr. K. Thompson, Dyneley JI.has -written me a long and excited to all the queries that have acctniu- Hall, Bramhope, Nr. Leeds. letter about his receptionof the lated in the postbag this week, but I Alexandra Palace sound transmissions on will try to get through them all by being Coffin's Coupler and Reception 7 metres. His receiver is a straight detector as snappy as possible. F.J. G. (Bridgend) has been reading and one L.F., made in accordance with the First, a whole packet of what I really about Collin's Coupler in the " Guide to best " P.W." traditions.Far from being must deseribe as very unintelligent queries Amateur Radio," and is anxious to know ashamed of it, J. I. M. says " I can receive anent the " Adaptor ' and its connection how to use it for reception purposes.I'm theB.B.C.7 -metretransmissionany to various broadcast receivers.I have been sorry to disappoint him, but he's barking afternoon I want to.Every time I have re -reading what I wrote on the subject, up the wrong tree.Arrangements like listenedforitIhave heardit."He and it seems to me that I covered it very the " Collin " are only suitable for trans- proceeds togivefullparticulars of the fully and in the simplest possible language. mission ;they are just devices to give programmes for several days. At least half -a -dozen readers He says that the percentage askMust I connect my accumu- of modulationappearstobe lator and A.T. to the Adaptor, or THE TELEPHONY EQUIPMENT verylow - the carrier -wave tothebroadcastreceiver,or comes over at ari extraordinary both ? "Now, I ask you !If strength. He wants to try out a you don't connect them to the super -regenerator on the trans- Adaptor, how on earth do you mission, and I am very keen that imagineit'sgoingto work ? he should do so and send me a Similarly, if you don't connect fullreport.Ihave not yet them to the broadcast receiver, heard of any really long-distance it just isn't a receiver,isit ? reception on a super-regen., and " Both," is the 'answer, without it would be more than usually further comment. interesting. Tricky Questions 5 -Metre D X I. D. McD. (Renfrewshire) asks A friend of. J. I. M.'s, by the threequestionswhichIwill way, has heardan American answer in public:(1) Can the amateur using C.W. on 5 metres. performanceofashort-wave I hope tohear more of this receiver be affected in any way shortly. by the presence of metal screws The Wirral Amateur Trans- in the wooden baseboard ?The mitting and Short -Wave Club answer is " Yes ;but not to a holds its next meeting on Wednes- noticeable, or even measurable day, January Oth, at the King's extent." Which is another way Another view of the equipment of the " Empress of Britain."The apparatus Square Café, Birkenhead.At of saying " No " ! shown hereisfor telephony only and was also supplied by Marconi's the last meeting there was a (2) Are there any wiresor Wireless Telegraph Co. junk sale and araffle. Full components in, a simple type of details may be obtained from short-wave receiver which should not be more perfect matching between the output Mr. B. O'Brien, Caldy, Irby Road, Heswall. parallel to, or near, any other wires or com- circuit and the aerial itself, and are pre-set According to the latest schedule, Moscow ponents ?Well, this answer isn't so easy. for a fixed frequency on which the trans- now broadcasts on 1,744 metres (Com- Generally speaking, the wiring of different mitter works. intern), 25 and 50' metres (R N E), and H.F. circuits (i.e. grid circuit and reaction A. P. J. (Hereford) has been in trouble 31.25 metres (R A N).Transmissions on circuit) should not be mixed up too much ; with an L.F.stage added tovarious 1,744 metres are always duplicated on and obviously it is no good spacing com- detector layouts.He has just found, how- 50metres by R N E,and,takeplace ponents out well, if the wires leading to ever, that when he omits the choke -filter regularly between 9 p.m. and 10 p.m., them are going to be all bunched up. Read output and puts the 'phones directly in except on Tuesdays and Thursdays. R A N my writings on the subject of " layouts " the anode circuit of the last valve, all is on 31.25 metres comes on every midnight. for the last eight years, and you'll see what well.That's an easy one ;there must be From Spain, both rebel and Government I mean. something wrong with either the L.F. choke stations may be heard broadcasting on (3) Is it possible for wiring between the or the 2-mfd. coupling condenser. severaldifferentwavelengthsandat components to be too short, causing insta- irregular times. On closing down, however, bility or other ailments on that account ? Morse Recording Too Difficult thesestationsfrequently announce the Yes ;if it means undue cramping together Another query :I say in my notes that time of the next transmission. of the components in the set. grid and reaction coils should be separated News from the amateur bands is not L.E.C.(Yelling)reports C 0 C D, by one turn, but some of the sketches of particularly exciting.Conditions remain Havana, on 48.92 metres from 10 till 11 coils show the windings about half -an -inch good on the whole, particularly on 20 p.m.The station is asking for reports, apart.Sorry, A. P. J.-you must blame metres, but 10 metres has been a little dis- which should be sent to Box 2294, Havana, my carelessness in doing the rough sketches, appointingafter the excellent promise that Cuba.An interesting " yeti " is returned. which are copied with scrupulous care by it gave a month or so back. By the time L. E. C. also mentions an interesting pro- the draughtsman ! this appears inprint, however,itwill gramme from L S X (Buenos Aires) on Will A. M. S. and others who still want probably be in full siving once more. 28.98 metres every Monday evening, from particulars of worse -recording apparatus, Australians have been heard on the 80 - 9.45 to 10.15 p.m. please take note that I really can't deal metre amateur band already.The best A. S. T. (Rugby) is wondering whether with it, after all ?The simplest form ofmonth for them is usually January (or to instal a short-wave set, on account of morse-recorder is too, complicated a job sometimes February), so readers who are tales that he hears from other listeners for the average home -constructor to tackle. keen on Morse reception will find it worth concerning interference from the G.P.O. In addition to that, one wants something their while .to keep an eye open on the 80 - station and its many short-wave channels. far more " beefy " than the usual short- metre band at about 6 p.m. for a while. I don't think he'll find things too bad, wave receiver before one can make use of it. W. L. S. Popular Wireless, December 26th, 1936. 43)

MEET THE BROADCASTING BACHELORS And read all about their views on marriage By SAM HEPPNER

THE examples of Austen Croom-Johnson, I can best describe my ideal conception of Fred Hartley, John Burnaby, Tol- a happy marriage by using a word which chard Evans and one or two others will be familiar to all who are interested in seem to have made little or no impression. wireless. During the last year or two, much confetti " The mind and personality of husband has been sprinkled in the direction of these and wife must operate on the same wave- personable young men who, saying fare- length ;there must be a perfect unity well to the light-hearted frivolities of their of attitudes-nofriction,no conflict- single days, have now assumed the stern but sufficientsense of humour and in- responsibilities of married life. tellectual activeness on the part of both But the broadcasting world still tcems to prevent the boredom thatfollows a with eligible young men who are reluctant to forsake the amiable pleasures of bachelor- Expert cooking, attractiveness, and civility on the hood-young men who, for a variety of PUNCTUALITY FIRST! telephone are a few of the desirable qualities reasons,remaintheir own unattached mentioned by RONALD HILL. property ! the steady, firm and enduring sort which Not "Anti -Marriage " lacks the feverish character of a summer At that little cocktail bar opposite the night infatuation." B.B.C. I recently sat and talked with I next had a word with Harry S. Pepper one of these gentlemen who stayed chatting on the question of his celibate existence. as long as he pleased, having no " better He was disposedtotreatthesubject half "-wielding the proverbial rolling -pin in a light and rather frivolous manner, in readiness-to whom he would have to but I detected a gleam of sincere opinion account for his late arrival home. Patrick beneath his banter.Harry's like that ; Waddington is his name. you can seldom get him tobe serious, " I'mnot' anti -marriage 'byany yet his jokes usually lend an inkling of his means,"confessedPat," but marriage real feelings. isn't always such a simple business, however much one may want to go in for it. When Cooking Important says Pepper " IthinkthatMrs. Harry Pepper," I marry, which I hope will be fairly soon- he said," should there ever be such a beforeI'mthirty,anyway-thechief person, would have a pretty rough time. quality I'll look for in a wife will he com- There'd be steaks like leather and pualings panionship. My wife must be a grand burned to a cinder if she waited meals for companion ;otherwise the marriage, as I me. You see, I'm always pottering about see things at any rate, will be a failure. at the B.B.C., hunting after concert party talen' ,and rushing to and from theatre BLONDE OR BRUNETTE dressing rooms at all hours.It simply " Punctuality " would be thefirstvirtueI'd wouldn't be fair to her. As it is, I live in look for in a wife, says HARRY S. PEPPER. Putney with my mother and don't seem to get time to think about making a separate complete tolerance of one another's ideas. home even if it could be managed with a I hate complacency.I hate smugness, guarantee of domestic harmony-even if and I believe that interest between two my punctual arrivals home were assured. people can only be maintained by setting And that's another thing.Punctuality ! off their separate characters against each Punctuality is a virtue I hold so precious other ;my idea of marriage isnot a thatIdeliberately keepoffmarriage complete mutual absorption of personality. because, living as I do, I can make no " The girl I marry will have to like the guarantee to get home at the promised things I like ;we will both like the same times.Therefore, if I did the sort of work books and music and agree on the general that enabled me to catch the six -fifteen principles of life.As soon as I am able to every evening and then desired to marry, escape from London I will.And my wife punctuality would be the first virtue l'd will want to come with me, away into the look for in a wife. And when I say punctu- country where we will ride and sail and ality I mean that I would want her to keep dance and keep a dog amid the simple dates within fifteen minutes of the appointed comforts of the home. times-and not a half-hour and ten minutes ! " My wife would have to be a first-rate The Right Basis for Marriage cook !That's an important item-and I'd " What sort of girl will she be ?In prefer someone in the same profession as appearance, brunette and petite, I should myself as, in a business like mine, cue's say-rather the Claudette Colbert type ; work is such a vital part of existence that yes, she's definitely my cup of tea. And I to carry the interest into the home and don't want to be wildly in love when I share it is part assurance of a full and happy marry her.I consider that a state of life.I think I'd like to marry a blonde- desperate,franticloveisentirelythe and she must have a proper idea of the GORDON LITTLE likes blondes and brunettes equally well, but his wife must be a good sport wrong basis for marriage ;the sort of love value of money.Another very important and, above all, essentially feminine. from which happy marriagesspringis (Please turn to page 443). 432 Popular Wireless, December 26th, 1936. WHAT DO LISTENERS LIKE BEST ? This is what the wants to find out. Will they be successful? By K. D. ROGERS

you see a nice, tall, well -dressed man is hard put to it to discover a method IFwalking up your garden path with a whereby it may find out listeners' likes and beautiful bright blue badge with the dislikes, but it does not contemplate any letters B.B.C. and an aerial rampant on it, house -to -house visits.After all, with close don't be alarmed. on eight million homes it would take a few He may be coming to ask you a few yearstocover the ground adequately. questions about your radio listening.It And it is not much good going to " repre- has been announced in the press that the sentative " homes as do the commercial B.B.C. is going to send out " men and firms when they want to find out if they can women with Oxford accents " to call on sell vacuum cleaners or tooth brushes in the you and to discover what you like best in'district. the way of radio programmes. Don't you believe it.The B.B.C. has The Only Safe Way taken on its staff a Mr. R. J. E. Silvey, If the B.B.C. is to find out what you and red-hot advertising expert, who is at work your neighbours like about the programmes Leslie W. Orton, president of the Anglo-Ameriean Radio and Television Society, and his fiancée, trying to formulate plans for finding out it must ask each person individually.It's Miss Eileen G. Harris, an official of the A.-A.R. what you like-and perhaps what you don't no good going to the man three doors away. and T.S. whose engagement was announced this like-in your radio programmes.But so Certainly not in my case.I know only month. far there has been no question of a house - too well that he is a Foundations of Music to -house visitation by these super -educated fan ;he is learning to " play " the saxo- men of the B.B.C. phone, and his foundations are still pretty A " RECORD" As a matter of fact, if you do encounter weak. a gentleman trying to get into your house At the moment Mr. Silvey is sitting in CHRISTMAS on the pretext of finding out what you like Broadcasting House with a wet towel You will probably be buying some about the programmes, deal with him round his head, drinking green tea. In new gramophone records to -day or harshly ;he is more likely to be trying to official words he is " quite unable to see to -morrow.Here are some hints find out what you like about your wife's anybody in regard to his work."I do not which will help you to choose them. jewellery or to get a good look at the know whether non -work subjects such as * family plate. darts would attract him, but on the matter AMgoing to start off this time with a serious note. The fact of the matter is that the B.B.C. of how the B.B.C. is to find out what we We have had such a spate of dance numbers like, Mr. Silvey is dumb. that I feel it is time to discuss one or two serious records.So, without any intention of punning, I am I don't blame him. It's going to commence with Robert Speaight, who takes "P.W.'s" WORLD FELLOWSHIP a nasty problem and the part of Thomas tti Becket in the play Murder in the Cathedral, which has been drawing full houses at one thatis going to the Duchess Theatre. take a deal of solving. On H.M.V. B 8499 Robert Speaight has recorded one of the speeches of Becket-the last sermon. A There are people who moving scene, and the actor's words come over with claim toknow, however. intensity and powerful drama. I am not as a rule enamoured of serious piano It has been stated that music on records. That statement will draw forth a the B.B.C. has made a howl of dismay and derision from some of you, no doubt. But I have a good reason. I like piano music. surprising discovery- I am fond of many of the old masters. But I do not by dint of analysing the consider that the average piano recording, even when fan " mail. it is that of a maestro, does the composition or the execution justice. There is a horrible flatness about many piano You'd Never Guess records that takes away from them the delicate transition from loudness to softness, and vice versa. And what do you You listen to any group of six piano records, and I think it is supposed to warrant you will find at least two that are just " adequate " as interpretations of that instrument. have discovered ? That I grant you that some well-known artists are Leonard Henry is num- comparatively soulless.But the recording seems to ber one favourite ? No. make them even more expressionless than they are in reality. Henry Hall ?No. Whether it is the control of the modulation by the recording engineers that causes flatness of some of According to the these records, or whether itis that the pianists information published deliberately level off their interpretations, I do not in this marvellous re- know. But the effect remains. port the B.B.C.has Two Good Piano Recordings found that talkers come I am therefore more than glad to welcome the first, with commenta- H.M.V. recordings of Rachmaninoff and Arthur tors next. Rubenstein on DA 1522 and DB 2450 respectively. Just think Rachmaninoff plays one of his own pieces, Serenade, that out, will you ? and also one of Borodin's Scherzos.Rubenstein has chosed a Dubussy Prelude and the Follow from ...... " Le Tombeau de Couperin," one of Ravers suites. Do you want a novelty record for Christmas? Try Some idea of the world-wide the imitation disc of Freddy Dosh (Decca F 6108). coverage of " P.W." is pro- Ducks, chickens, a howling dog, trainload of cattle, a vided by this group of letters baby, a London Underground train, sounds in an which arrived ina recent airport, and even Sir Malcolm Campbell's Bluebird batchofapplicationsfor are included in the record. Quite a lively and unusual literature mentioned in the one-and-sixpennyworth ! "Link Between."The Hildegarde is still hard at it. When she recorded the countries included Australia, record I do not know, for I believe she is still in New Zealand, India, Ceylon, America, hut Columbia FB 1523 holds a very good Manchuria, China, Palestine, " likeness " of the popular cabaret and radio star. Federated Malay States,South When I'm With You is the title and-well, it may Africa, Northern and South- make you wish she were. ern Rhodesia and Portugal. (Please turn to page443.) Popular Wireless, December 2titit, 193(i. 433

THE theoretical be drilled for the contact screws-the con- circuitand tact screws are mounted. Make sure that full details of the nuts are tightened up well, and that the the design of this soldering tags are in the correct positions. receiver were Now clean contact screws with a fine file, given last week. Consequently, this article and remove all brass filings with a brush. will be purely constructional, except in Cut stop " V " withthree -cornered file. such instances as it is necessary to explain Cut finger control slot with f in. rat-tail some practical point by theory. file.That completes the switch disc. The only thing in the receiver which calls The next job is to prepare the aluminium for any really careful constructing is the baseboard.If you have not bought this switch gear for wave -changing.Not that A full constructional description of the already cut to size, it must be cut to mea- this is at all difficult, but it certainly must high -efficiencyall -mainsreceiverfor sure 14 in. x 10 in. television sound and ordinary broadcast- Drill the holes for the be made reasonably accurate in order to valve -holders. A centre -cutterisreally One ing, first details of which were given last as are its operating consistently well. week. This set provides a new and necessary for these holes, but they may be of the most important things which assures fascinatingfieldofentertainmentfor cut by drilling small holes-say * in.- this is clean contact points.This is very those within range of Alexandra Palace. roundthe circumference close together, and important.It will be mentioned at least then you will be able to tap out the centre. once more later on so that you will not forget The holes for V1, V2, andV3 are lj in. it ! accuracyis necessaryin drilling theholes, as diameter. As to the general form of the receiver, it the screws have to register with the contact The hole for the rectifier is 1 in. diameter. consists of an aluminium baseboard sup- stripsonthe baseboard. Whentheswitch Next drill twoin. holes for the two 8-mfd. ported by side, front, and back pieces ofdisc has beendrilled-I-in. holes should electrolytic condensers. Now drill the holes plywood. The sides and front are of for mounting the components. These fin. wood. The back is 1 -in. wood. THE TELEVISION COIL should be * in. in diameter.Their The back is thinner as it carries the positions may be found by placing the terminals and on/offswitch.The components on the baseboard, and front is cut away in places, as will 18gLead A marking through the fixing holes of be seen in the photograph of the the components. front view. (See last week's issue.) III) I ruMIIMPAP 10111 Fixing the Contact Strips 189 Lead .8 Lead A Component Warning rr-- I NOW turn to the diagram showing Before starting on the construction, !8g Lead C' the positions of the contact strips on make sure that all the components Long. the underside of the baseboard. The are of the correct type. Please do not holes for these should next be drilled, substitute other makes or types. This /o,,,-/ D' together with the holes for the' stop may be fatal to proper results.You 7-a4vi4 SA,Leati146 aia.t Lead strip and the pivot screw.The holes have heard this warning for years, (Cedtpto to /8 .5 w re/1,7.ex( Ca/z/u3,-)vBieSWG for the contact strips and stop strip but itstill holds good !Indeed it r arein. diameter, whilst that for the is more necessary to -day than ever pivot screw isa in. diameter. it was to use the specified compo- Now we come to the contact strips. nents. Of course' such things as fixed How the 7 -metre coil is made.It is a very simple winding, but Theseare made from thin springy brass. condensers and fixed resistances may the dimensions given should be strictly adhered to. It has already been suggestedthat the be substituted provided that they contact stripsfrom old flash -lamp are similar electrically and physi- batteries be used for this.The cally and of a really reliable make. size and shape of these are shown The more vitalparts, however, in the separate diagram.They must not be changed.. Such things should be fitted to the baseboard as coils, smoothing choke or mains andbentto shape afterwards. transformer must certainly not be The fixing screws are counter -sunk substituted, otherwise results will 0 B.A. by in., and are sunk into most certainly be affected. the top side of the baseboard, the The first job to tackleis the nuts being on the underside-the switch -gear.This consists simply contact strip side. of an ebonite disc, a 2 B.A. pivot It will be noted that two strips screw, four 2 B.A. nuts, some are bent to one shape, and two 6 B.A. nuts and screws, some sol- to another shape. Strips B and C dering tags, and some springy brass are bent up to form stops, so strip. This last may quite well be make sure you have these the the contact strips from an old right way round, otherwise the flash -lamp battery. switch will not function properly. The ebonite discis3in.in The stop strip is easily bent to diameter, and in. thick.The the shape shown in the diagram. positions of the contact screws Thereisnothing verycritical (which are 4 -in. x 6 B.A. brass about this, except its position on cheese -heads) are clearly shown in the baseboard. the diagram.The only comment Next, mount the side supports. necessary hereisto state that Fit wire to moving vanes tag of thepositions of these screws are This view looking down on the top of the chassis shows the clean, straight- tuningcondenser. Thisgoes most important, and reasonable forward layout.The rearmost valveholder is for the rectifier valve. (Please turn to page 435.) MAINS -DRIVEN RECEPTION A41,P41-721,46"" fdr"63( Fso it C"'" -c-441" OF BROADCAST AND ULTRA -SHORT WAVES

In this wiring diagram the sides of the chassis have been flattened out into on the right, is visible. Where wires pass through the chassis, the holes are numbered to correspond the same plane as the top of the chassis. All the under -chassis wiring, which includes that to the mains transformer with the above -chassis wiring diagram. Popular Wireless, December 26th, 1936. 435

THE "A.P." A.C. THREE single lengthof sleevingis slipped over them. Leave abou` (Continued front page 433.) a foot.It cal be cut to length when wiring is done. through the baseboard to contact strip on underside.This is shown in the wiring Baseboard Mounting diagram.Mount tuning condenser. Now mount the remainder of the components of the base- Concerning The "V " Stop board. Those on the side Now mount the switch disc on the pieces should not be mounted underside of the baseboard.The method yet.Before mounting these of mounting this is shown in a diagram. components the wiring of the Make surethat thecontacts " make " components on the baseboard properly, and that the " V" stop functions shouldbedoneasfaras as it should do-i.e. stops the disc at the possible.After this, fit back appropriate positions.This is the long - support, and mount remainder THE ABOVE -BASEBOARD WIRING This close-up shows clearlythe methodof arrangingthe7 -metrecoilandthewave - change switch. itsbracketso thatthecentre of the -4mIN71:=../Ci 1 LiA spindle is in. from the end of the base- ' - oa --O a 7 .":". B... 0 6 (..) board. Similarly, the spindle of the volume . 8 , I i control potentiometer is 21 in. from the /I f other end of the baseboardThe tuning control knob is, of course, central. vac. i , rlanv/aGt, The front support should be cut as 4/ 4012/ess ..*4.77....e shown in the photograph of front of sc t ( 2 goes, Z..*2- Can.( which appeared on page 409last week: / Qwoo. a . Alfa .a- 6c ..r,,,,...... - , oO-a The three pieces cut away are all 3 in. wide .1n+1 gam/ 08 V_DJ / o Ag and 3in.deep. The distance between a dilifiliii.,,...1 ....-. . I- .... 0 6 these cut-outs is 11 in., and the vertical 0 0 end pieces are 0 o 0 0 .7.&,,,a"..'tZ".9 OV 0 in ,wide. The front support e o0 o 041. o having been fitted to the baseboard, the set 0I/2 0 e o ;...t:, ay.6 0 0 02} 0 is complete. No panel is shown, as this is Z kr C./. 0 0 Ki re best left to the constructor to decide, its q" 1/2 /NAY 7YI t6CG-mv, (Continued overleaf) EZ.BcABC3Bac ; ; HOW THEY ARE PLACED ,/,'"CI:prism III 4_,-/k.ree Pe-4171/eZ- C./BoBt.e 34 Dthin:02 ea.e E ) 2 54 . Saeteur)

AE`C.rele-e-4. SAVce Eleci,oZyac CZYzizzet

The above -baseboard wiring and layout.It should be noted that certain terminals on the coil units are 4 not used.These are 6 and 7 on the aerial coil and 7 and 8 on the H.F. transformer.The sketch on the right gives the positions of the contact strips beneath the switch disc. 1''eI 54.,./ wave position, when all contact points are of components.It is advisable to remove Contact Co/7_42..cz- ,47- sr/r-gt. broken. side supports in order to fit the components C' That completes the switching arrange- to them, and then refit them to baseboard. ment.The coil for the 7 -metre reception Now complete the wiring. GlazierA.sr-de should now be made.The method of The positions of the controls on the of Cluts,cis Ceeit/re Lim ,e making this is quite clear in the diagram. front of the set are as follows.(It may 5E4,0, It should be pointed out, however, that not be possible to find these positions az- with. 684 x34; the aerial coupling coil is a single turn of accurately from the diagrams).The re- Soieum.rmien. wire, the ends of which are left long, and a action condenser should be mounted on * YOUR "A.P." A.C. SHOPPING LIST Wearite " Unigen " coils. 1 Dubilier 01-mfd. fixed condenser, type 629. 1 Bulgin toggle on!coff switch, type S.83. Polar 2 -gang Midget tuning condenser, each section1 Dubilier '001-mfd. fixed condenser, type 673. 1 Bulgin twin fuse holder (with 1 -amp. fuses), type .0005-mfd. 2 T.C.C. '002-mfd. tubular fixed condensers, type 303. F.16. Polar V.P. horizontal drive for above. 1 Dubilier 0001-mfd. fixed condenser, type 655. 1 aluminium sheet, 14"x 10"-18 S.W.G. (Peto- Clix chassis -mounting 7 -pin valve holders, type V2.1 T.C.C. '00005-mfd. fixed condenser, type M. Scott). Clix chassis -mounting 7 -pin valve holder, S.W. type.1 J.B. 0003-mfd. solid dielectric differential reaction1 yd. single screened flex (Peto-Scott). Clix chassis -mounting 4 -pin valve holder, type VI. condenser. Bulgin H.F. choke, type H.F.8. 1 Erie '5-meg. resistance, 1 -watt type. 2 pieces r plywood 91" X for side supports B.T.S. H.F. choke, type U.H.F.1. 1 Erie 100,000 -ohm resistance, 1 -watt type. (Pete -Scott).' J.B. baseboard trimmer, '0001 mfd. 1 Erie 8,000 -ohm resistance, 1 -watt type. 1 piece I" plywood 131" X 4/" for frontsupport Varley pentode output choke, type D.P.9. 1 Erie 1,000 -ohm resistance, 1 -watt type. (Pete -Scott). Wearite smoothing choke, type H.T.12. 1 Polar-N.S.F. '25-meg. resistance, 1 -watt typo. 1 piece i" plywood 14" x 41" for back support (Peto- Varley mains transformer, type E.P.20. 1 Polar-N.S.F. 1-meg. resistance, 1 -watt type. Scott). Dubilier 4-mfd. fixed condenser, type L.S.A. 1 piece llz"ebonite to make 3" diameter switch -disc 1 Polar-N.S.F. 50,003 -ohm resistance, 1 -watt type. (Peto-Scott). T.C.C.8-mfd. wet electrolytic condensers, type 802.1 Polar-N.S.F. 150 -ohm resistance, 1 -watt type. T.C.C. 50-mfd. electrolyticcondenser,12 -volt Brass for contact strips (see text). working, type F.W. 1 Dubilier 50,000 -ohm resistance, 1 -watt type. 6 B.A. screws and nuts, wood screws, flex, etc. T.M.C. 2-mfd. fixed condenser, type 40. 2 Dubilier 20,000 -ohm resistances, 1 -watt type. Dubilier 1-mfd. fixed condensers, type B.B. 1 Dubilier 5,000 -ohm resistance, I -watt type. 5 Belling and Lee terminals, type R. Dubilier 1-mfd. tubular fixed condenser, type 4503.1 Erie 10,000 -ohm potentiometer (without switch). 6 yds. 11 m.m. insulating sleeving (Peto-Scott). *T.C.C. 1-mfd. tubular fixed condensers, type 250.2 Peto-Scott 21" mounting brackets with long slot. 30 ft. 18 S.W.G. tinned copper wire (Peto-Scott). 436 Popular Wireless, December 26th, 1936.

THE "A.P." A.C. THREE to medium -wave position-i.e. to the left.Tune -in a local (Continued from previous page.) station and adjust trimmers 144zs/w-kr 11.holc/Arzcle rx 28A 5c4e-w- for maximum signal strength. ofChasses. C Pot) size depending on the cabinet to which the The signal should be kept at a Base set is fitted. fairly lowlevelto do this. /4 , / /4 In order to test the set the following Now tune to a station at the instructions should be followed: Fit valves lower end of the scale, say 'A; son in appropriate holders. Connect aerial about 250 metres.Turn up (to A2) and earth.Connect loudspeaker. reaction (anti -clockwise) until These Suo Na4r erne 28 .4./Va4' (4.7-116ek) the setis on the verge of Coaked tasset/Ler- oscillating.Keep volume to SWITCH CONTACTS fairly low level by means of /a volume control.Adjust rear The switch disc moves on the threaded -rod spindle, which is secured trimmer of tuning condenser by nuts to the metal chassis. Contact V'-3- for maximum signal strength. 4 .5&ths 8a C The receiver is now ganged correctly.Set * wave -change switch to long -wave (central) 5/32 Fir -wry h'ola position, and see if the long -wave section is WATERPROOFING ROPE functioning correctly. * AtC Bent a. Set wave -change switch for television tho.s. s/u2/te signal (to the right). Connect aerial to Al. ANY rope which is to be used for outdoor If a di -pole aerial is used, the two leads aerials, no matter whetheritbe should be connected to terminals Al and new or old, can have its life enor- mously prolonged Contact bygivingita A AD COMPACT ASSEMBLY IS ACHIEVED simple creosote 4 treatment. VEI. Aide Place into a 4 a D Beata:. bucket or basin a mixture of equal Foang hole parts of creosote Details for making the switch contact strips and paraffinoil, are given here. stirringthetwo liquidswellto- This should be adjusted for pentode if it gether.Then im- has any adjustment.If it has not, the merse the rope in matching should be done by adjusting this liquid mixture connections to output choke, as advised in for a minute or leaflet supplied with same. Connect mains two, taking care to leads to mains socket. Make sure that you see that the liquid * covers every por- VALVES FOR THE "A.P." tion of the rope. The rope is now A.C. THREE withdrawn from the creosote - V.1. V.2. Mazda A.C./V.P.1.Mazda A.C./S.2./Pea. paraffinmixture, shaken to remove V.3. Rectifier Marconi or OsramMarconi or Osram surplusliquid, N.41. M.U.12. after which itis placed in position on the aerial mast, have connected the correct tapping on How the receiver appears from below the chassis when in its completed form. orinwhatever mains transformer before doing this. situation itis Screw out slotted head front trimmer of A2. The television sound signal is received intended to be used. tuning condenser until itis nearly free at approximately 26 on the tuning dial, Such a rope will not only remain water- from screw.Screw down (clockwise) back whilst the vision " sound " is received at proof over a long period, but it will actually trimmer as far as it will go, but do not force about 18.The reaction condenser now repel water.In the summer -time,too, it.Now turn it back half a turn.Screw worksintheoppositedirection-i.e. it will not become dried up by the hot rays down .0001-mfd.baseboard trimmer as increases reaction when turned clockwise. of the sun. -J . F. S. far .as it will go, then turn it back two There is just one point in the wiring complete turns.Set wave -change switch diagram which may not be quite clear : The wiresjoiningthe 4-v. THE LOCATING STOP DETAILS OF REVOLVINGDISC 4 -amp. winding on the mains transformertotheheater Filed oat ArAzyte* Cone/rol terminals of V3 are not drawn. These leads have been omitted Avec hole Vg Det: to prevent confusion in the drawing.Itwillbeseen that these points are marked Coltact X " andY " on both the Sceftscus/.,.rid (684 6-5e, transformer and V3.When on. ande,sse.d.e) wiring, " X " on the mains and Soldeoceng Gay.5 transformer should be con- nected to " X " on V3, and 4 " Y "on transformerto Y "on. V3.These leads, 744 qt.SaAe..tcii Z2esc of course; must not be omitted, Stoi'V" 34 EGAnc43. orthereceiverwillnot function, as the valves will Details othe long -wave locating stop.The The ebonite disc, which is turned to change wave -ranges, is pre- strip engages with a " V " cut in the wave - pared in accordance with these dimensions. receive no heater current, change switch disc. Popular Wireless, December 26th, 1936. 437

FROM OUR READERS YOU MIGHT have something of great interest to other readers to tell, some experience, some idea A NEGLECTEDWAVEBAND or opinion connected with radio.Write us a letter on any radio subject. We like to mitters (trawlers use only up to 100 watts). hear from readers, and a guinea is awarded An old follower of "P.W." gives each week to the sender of the letter which, My receiver is the faithful old 0-v-1 standby, in the opinion of the Editor, is the best one. some useful tipsindescribing with an 80 -foot indoor aerial and head- This week it goes to Mr. J. Royle.Length andliteraryabilityareno criterionof phones.I use a very small " vernier " success, everyone stands an equal chance. some of his radio experiences. condenser for super bancIspread, and it is So remember you may TI invaluable on this as on the short wave- bands. WIN A GUINEA The Editor, POPULAR WIRELESS. Yours faithfully, Dear Sir,-I wonder how many radio F. W. T. ATKIN: " fans " listen on the upper short-wave 25, Hayfield Crescent, Freeheville, My first discovery was the bad state of the aerial. band (80-180 metres) ?It seems to be Sheffield. It was of 7/22's non -insulated wire, and was brought to the set by cutting a groove in the window ledge rather a neglected band nowadays, and I and fastening the window on it.To insulate it I bound notice that the majority of "all -wave " sets IMPROVING SHORT WAVES the lead-in with tape ;never again, for after some do not cover it at all.(By the way,wouldn't The Editor, " Popular Wireless." five weeks of trouble tracking I found the tape, soaked by the rains, causing an H.F. leak.I replaced the " multiple Waveband " be a more logical Dear Sir,-As an old follower of" P.W." and offending lead by one of insulated wire, and all was name for these receivers ?)A few years one who makes a pointofreading your weekly well. I next cut the aerial to about 20 ft., inclined it correspondence, I have been wondering if a word or from the chimney -stack down to the window, and ago there was literally " nothing doing " so on divers subjects from me might prove of interest. things were even better ! on this band, except for the amateur Just to substantiate my claim of " old follower " My most important find was that with a condenser transmitters on 150-200 metres, who had and to revive memories of great and former days, and plug-in S.W. coils connected across the aerial I wonder how many could name the two following and earth terminals I could tune the H.F. valve. just been pushed down from 440 metres circuits 1'They were two high spots of yours years The set actually utilised the primary of the long wave out of the way on to a " useless " wave- ago if I remember rightly, and performed great deeds. H.F. input transformer as a S.W. choke, but it was Here they areinalltheirglory t(Reproduced evidently so inefficient that the coil and condenser length.Then, transatlantic working was below.- ED.) was the easier path for H.F.Anyway, by tuning the achieved by them around 100 metres. I have several more of these grand old fellows, aerial circuit, volume is increased enormously, like- Well, now the band is a busy one, and valve and/or crystal,in my notebook if anyone's wise selectivity.Here, then, is an idea which is worth interested. trying on any straight aperiodic three-valver. I can promise those readers who are not 'To return to present times.I am, of course, ex- My last idea is for all who, like myself, live in a top - familiar with the band, plenty of interest ceedingly interested, and have been for years, in S.W. floor flat ;it concerns the earth.I am too high up work.My receivers were all definite hook-ups, so for a decent earth in the garden, so. after exhaustive if they will beg, borrow, or make coils to after my marriage my special hook-up " retired " 0) tests,I have installed two earths in this manner : tune between 80-180 metres. to the loft and I had to cast about for an A.W.Dis- very near the set is a large brick fireplace, protruding liking superhets, and with one and a hall eyed on the into the room ;upon this I put a sheet of copper foil I give below some typical extracts from cost, I bought an A.O. A.W. 3 (pentodes) of very well- and take a lead from it to the set.This is used very my log, all round 9-10.30 p.m. (or a little known make, and endured indifferent reception on successfully for 20 m.'s down ;above that, the second earlier in the case of the " hams ") : S.W.'s for some time until I hit upon the three follow- earth is used.This is a wire connected to the tele- ing ideas.I am not given to exaggeration, but I would phone sheathing (around the cable) on the roof ; 173 metres.-A 100 -watt broadcasting say improvement is at least 300 per cent. thus only a short length of wire, about 10 ft., is used. station, Liepraja (Latvia) giving a talk in I find this perfectly satisfactory. I should be interested to know what others use in English, on agricultureinLatvia.In- DO YOU REMEMBER? like circumstances. teresting. In conclusion, I should like to say that here, in 160 metres.-An amateur working duplex Kingsbury, at the moment I find reception very good, particularly from the Americans.Amateurs, too, are withanother.Theotherwasbarely heard from all over the world, although I hear them audible, but his remarks must have been say conditions are so bad amusing, judging from the hearty .1aughter Wishing you and " P.W." all the best ! Yours faithfully, of No. 1. J. ROYLE. 150metres(approx.).-Severalpolice 2, The Triangle, Buck Lane, headquarters calling patrolcars.I am Kingsbury, N.W.9. not at liberty to repeat what I have heard (see back of Licence !), but I can say that A YOUNG ENTHUSIAST thrills are often obtained by listening to The Editor, POPULAR WIRELESS. (these stations. Dear Sir,-Although only 13 I have got the 130-140 metres (approx.).-Literally radio bug firmly planted in me, and have at this dozens of trawlers heard, and very enter- tender age built six receivers, from crystals to taining, too !They are difficult to pick three-valvers. I first became interested in radio about three up and more so to identify, as they are years ago.Soon after, I became the proud on only a few moments at a time, as a rule. possessor of a crystal set, which after thoroughly One oldskipper was hearddistinctly testing I had to come to the sorrowful decision contravening Section 113 of the P.M.G.'s that the set was no good ! However, determined to possess a receiver of " Handbook for Wireless Telegraph Opera- some sort, I built a plug-in coil one valve. tors," i.e. " Operators are reminded that (And what a job I had to get the coils 0 Event- itis forbidden ... touse offensive ually I had to rewind them myself. language " ;thatis,if the ;very hearty This set gave splendid results, working on a and frequent use of a word first introduced Pix aerial and a gas -pipe earth.I used to receive a German station tremendously loud on to the stage by Mr. G. B. Shaw is using a 200 -turn coil. considered " offensive language " by the A year later I built a two -valve ;the results P.M.G. ! obtained with this were very good indeed. 100 metres (3,127.5 kcs., to be exact)- A month later two school friends asked me to GBTT (R.M.S. " Queen Mary ") speaking make sets, one a one -valve and the other a. crystal.I did this for them and sold them the to the " Empress of Britain." sets, both to their pleasure and mine. Finally on 80 metres, a large number Then a great honour came my way.An old of British, Dutch, French, and Belgian gentleman friend of mine asked me to make him " hams." either a two or three -valve set.I made him a The above represents a selection from my two-valver.He wasn't satisfied with the results however, and when coming across anold logs for several evenings, but I think I have " P.W." copy in which the Skyhawk " was said enough to show that it is well worth described, I promptly built him it, and he's very while" breaking -in " on this band. A satisfied. warning!Becauseyouarenearthe Wishing the best of luck to " P.W." from broadcast band, do not think any old which I've derived much useful information, " ham-handed " tuning will do.It won't. Yours faithfully, In his letter Mr. J. Boyle wonders how many can C. BETHENCOUNT. Just as much patience as on 20 metres is name these two " P.W." circuits of many years SunningdaleHouse, Sunningdale Avenue, needed to get these weak telephony trans - ago. Eastcote, Nr. Pinner, Middlesex. 438 Popular Wireless, Decemb?r 26th, 1936. RANDOM RADIO REFLECTIONS By Victor King B.B.C. News Service-A Haunted Television Receiver ?-And They Haven't Got a Radio Set-Balance and Control at AlexandraPalace.

GREETINGS. across.I at once I CAN'T send you all an individual season's sat up and took greetings, so please accept collectively notice, for this was and severally and altogether my best real stuff coming wishes for a Merry Christmas and a very in from outside. Happy New Year. You know,I was No sooner had invited to do this in the special Christmas the last cloud (or number of " P.W.," but I craved permission moth -ball), van - to get my words nearer to the festive ished than there Radio is part and parcel of family life, and children enjoy broadcasting as much season itself.For I'd like to pop in and were more very as their parents.At any rate these kiddies are firmly of the opinion that they out of your parties-if you'd have me and bright flashes like couldn't do without their Marconiphone Table -grand. it could be done. forkedlightning, However, I can at least speak to you- and for a fleeting moment a face appeared. Voices fade right away, and background in these printed words, and so, once again, It was hardly anything more than a smile noises rise right up, as the man at the all the best and may you enjoy smooth wrapped in barely discernible features. wheeltriestokeepthemodulation and contented going in 1937.- No, there were no sounds at all from moderately even, and then, suddenly, he'll theloudspeaker.No ghostlysighsor be caught napping and there's such a roar RADIO NEWS BULLETINS. spectral mutterings.But it gave me a from the loudspeaker that you nearly got IN my opinion the B.B.C. news service has prickling round the back of the neck to your hat blown off-if you're wearing one. not measured up well during the past see that vague face flutter into view and However, I'm not making a point of few weeks.It has been tried and found as quickly vanish. this, so breathe again you televisionites of wanting.It " scooped " the evening news- The set was tuned off the B.B.C. fre- the B.B.C. quency-to something like 47 megacycles, papers with the Crystal Palace fire, but such B.B.C. THEATRE ORGAN. was the eager absence of restraint displayed I should think.It may have been a B.B.C. in putting the news on the air that vast test transmission, nevertheless, or Baird T BELIEVE the B.B.C. arc applying much crowds, which severely hampered the fire- or M.-E.M.I. may have had something to less than their usual amount of control men and police, were caused to assemble. do with it.Or it may have been a freak to their new theatre organ.That is to And then came the graver events of that reception from the Continent. say, they are allowing a wider compass week, and this time the brake was put on I hope so. between minimum and maximum loudness, so hard that for a while the broadcast news I should hate to have a haunted tele- and yet I wonder if the majority of listeners concerning it was negligible and meaning- vision set ! want this ? less.Not a word appeared in the current Wraiths could throw all my testing right For myself, I like a fairly narrow com- out. pass.I prefer the control engineer to do issue of the " Radio Gazette," which is his stuff with a fairly heavy hand-but billed as a " Recorded Review of Events THEY'RE VERY MUSICAL I at Home and Abroad." adroitly, of course.But then. I generally In fact, so strictly was the policy ofITHOUGHT that practically everybody listen with the wick turned fairly well down. " bulletinism " applied that no trimmings owned a radio set these days, but I've With a wide volume compass at the B.B.C. The absence of just heard of a family that doesn't, never end this means that pianissimos vanish of any 'kind were supplied. has done, and apparently never will. almostentirely-pp's become ppp's,in comment could be forgiven, but not that of I heard about them while discussing with fact ! explanation. friends a famous pianist whose son is the I think it must now be quite obvious to originator of some rather childish radio all that broadcasting, as it is at present melodramatics (three guesses !). HALF CANADA NOW directed, will never prove a serious rival " Mrs. Jones (that's not really the name) to the Press:For myself, I look to the is a beautifulpianist ;good enough for LISTENS radio to provide a few headlines (dispas- the Queen's Hall," said someone. NEARLY one half of the population of sionately and unenterprisingly composed) There were polite and uninterested little Canada are now believedtobe and my newspapers for the body of the noises from the others. listeners on the radio, according to news, together with expert explanation " Mr. Jones plays the violin magnificently the Canadian Department of Trade and and commentary. into the bargain," he went on. Commerce, which basesitsestimate on By the way, it was one of my most More stifled yawns. nearly 800,000 radio licences sold during the pleasant surprises when, a year or two ago, " In fact, they're a very musical family first six months of the present fiscal year, I learned that my two morning papers, and have one of the largest libraries of which started April 1st.Based on last the " Daily Telegraph " and the Daily gramophone records I've ever seen." year's figuresfor thefirstsix months, Sketch " were cousins of POPULAR WIRE- " Shouldn't think they get much time to 627,000, and the total for the year, 862,000, LESS. listen to the radio," I suggested idly. the department believes a million licences And then he sprang the surprising fact at Two Dollars will be sold this fiscal year. HERE'S A MYSTERY. that the Jones haven't got one.Or is it With five members to a family, at least T HAPPENED to be playing about with surprising ? five million listen, half of Canada's entire my television outfit at around about population. two o'clock in the morning a few days ago. AT THE A.P. Other factors which indicate a growing As a matter of fact, I was trying a novel THE control engineers at the Alexandra Canadian listening public, the department testing stunt due to A. S. Clark, " P.W.'s " Palace have a pretty hectic time. point out, are the sale of 190,000 receivers chieftelengineer." Judging by what comes out of my television last year, as well as the fact that free Suddenly, some bright flashes appeared outfit in the way of sound, the television licences to the blind have jumped 400 on the blank screen.Then what appeared producers haven't yet mastered the balance during the first six months to a total of to be either a series of small round clouds and control of vision and sound together 2,314.There were 589 free licences in or a bunch of magnified moth -balls swept by a very long chalk. 1930. J.M. Popular Wireless, December 26th, 1936. 439

RADIOTORIAL QUESTIONS AND ANSWERS By K. D. ROGERS HOW TO REDUCE H.T. CONSUMPTION C.H. (Mahon, Yorks).-How canI should be able to do this scheme quite well, and to get a good " squawk " on your set whenever Miss S.G., PENTODE AND VAR. MU. reduce the H.T. consumption of my set C. A. R. wakes up. A. P. J. (Hereford).-What is the differ- which takes 22 milliamps at present ? It is a The sketch will show what I mean. ence in the functions of the S.G. valve, the If you wanted a permanent connection you could straight set with ordinary triode output and connect straight to the G. terminal and do away with H.F. pentode and the variable mu pentode ? has two L.F. stages. the adaptor, of course. I have been told that you can use an H.F. You can use either Class B. or Q.P.P. output.I pentode as a detector.Will that fact apply would recommend, in your case, the cutting out of UP TO SHIPPING the one L.F. stage and turning the output stage into also to the other valves mentioned ? a Q.P.P. stage, using one of the special double J. E. (Leeds). -1 have, a three -valve set To answer your last question first. You can use a pentodes made for the purpose. with plug-in coils of the six -pin variety.I screened -grid valve quite well, but I do not recom- By this means you would cut out the current taken want to get up to 600 metres with it,but mend the variable mu valve as being such a good at the moment by tlie first. L.P. stage, and you would detector as the plain pentode or S.G. only consume current in proportion to the strength although I have wound coils I can only get of the signals in the last stage. As regards sensitivity and power, you would probably find that the use of the'NorthRegional withterribleshrieks. the pentode as a last valve would compensate for Can I use plug-in coils up there ? lteGe the removal of the intermediate L.F. stage.You Without details of your circuit it is difficult to would be getting better amplification from the advise you. It may be that you have an H.F. stage pentode than you are now getting from the triode that becomes unstable when you get to the longer output valve.Probably your average H.T. current medium waves, or in your case you may have wound consumption would fall to about half the figure you the reaction winding. too large for the 600 -metre mention.The alteration of the circuit is easy, and coil.It should be possible, provided the set is not No Corn-ec,,on. the only other parts you would have to buy would unstable, to go up to 600 metres if you use the correct be the input and output Q.P.P. transformers and the coil. Your best plan would be to send details of your present coils, or even one of them, for our inspection, so that we may advise you as to the necessary wind- The Editor cannot accept responsibility for manu- ings. Also let us have details of your set. Please be scripts or photos. Every care will be taken to return absolutely frank about the question of stability. MSS not accepted for publication.A stamped, Try the set with your home-made 600 -metre coil with addressed envelope must be sent with every article. the reaction winding disconnected or short-circuited Lz`Vcistswdoldet.f.. All Editorial communications should be addressed so that there is no question of that causing the to the Editor, " Popular Wireless,- Tallis House, instability, and let us know if the set is then perfectly Tallis Street, London, E.C.4. stable. All inquiries concerning advertising rates,etc., D.C. SET ON A.C. MAINS to be addressed to the Advertisement Offices, John Carpenter House, John Carpenter Street, London, J. W. C. B. (Weymouth). -I have an E.C.4. El:co D.C. three -valveset, but unfortunately The constructional articles which appear from the supply in this district is A.C. lime to time inthis journal are the outcome of Can I get research and experimental work carried out with a a rectifier which will enable me to use the set zFr view to improving the technique of wireless reception. on these mains ?The rectifier I have in my As much of the information given in the columns of this paper concerns themost recent developments possession will not pass sufficient current to in the radio world, some of the arrangements and enable me to run the set. /114 4e 8,are-sy specialties described may be the subjects of Letters E It is possible, but without details of the amount Patent, and the amateur and the Trader would be of current the set takes we cannot advise. You do The suggested connections for the scheme asked well advised to obtain permission of the patentees to not state the exact model you have.It would be for by C. A. R. (Worcester Park). use the patents before doing so. best for you to write to the makers of rectifiers for The function of S.G., pentode and variable mu details of what they can provide, but I think you pentode is similiar in each case. They are all amplify- * * will find it an expensive job.I really consider it ing valves, the pentode having greater stability and Q.P.P. valve holder and the Q.P.P. valve.But, would be cheaper to get your set changed, if you can, greater amplification as a rule than the S.G. But the believe me; the alteration in the anode consumption for you would have to pay something like £8 or £10 variable -mu valve is so constructed that as the grid would be well worth the cost of the materials. at a minimum for a rectifier which would deliver bias on it is varied so is the amount of amplication sufficient power for the operation of your set. obtained from it. LISTEN FOR THE BABY However, it would not be amiss to drop a line to Thus, if you use it for a leaky -grid detector, you Here is a query that will strike a sympa- the Ediswan ElectricCo.,Charing Cross Road, will find that it will not give such straight line do- London, W.C.2, and ask what sort of rectifier they te( tion as the ordinary S.G. or pentode, owing to the thetic chord in the hearts of many of you. have available, and also the Electric Dynamic Con- fact that the grid will become snore or less negative Incidentally, it may give rise to some in- struction Co., of St. Mary Cray, Kent, and ask what according to the strength of the signals. rotary converters they have for tackling the job. It would work, of course, but it would not be so teresting letters providing alternative solutions But I think you will find that these things are not to good a rectifier as the " straight " non -variable mu - to the problem. be obtained at less than the figures I have mentioned. valves. C. A. R. (Worcester Park) wants to know how to listen for the baby upstairs while he is also listening to the local station on his radiogram ? This is what he says : TECHNICALITIES EXPLAINED-No. 34 "Our Baby is a few months old and is put to bed on the top floor every night at 7 p.m. GAS -FILLED DISCHARGE VALVE " If she should awake during the evening, we are NT This valve is used extensively for cathode-ray unable to hear her with the wireless going, unless we -/- television time bases. Itisa triode, filled go to the bottom of the staircase, which, of course, is usually with helium or mercury vapour. Helium not always convenient. is generally acknowledged to be the better as it " I have tried an arrangement with a speaker over gives a quicker and more certain action. There her cot coupled with flex to the P.U. terminals of the is a heater just as in an A.C. valve, but that wireless set (5 valves Philco ' superhet). isleft outin the diagram for the sake of " This arrangement would be quite satisfactory sim plicity. except for one disadvantage --the need to switch over Across the valveisbuilt up the scanning to P.U. before we can hear if anything is doing. potential.This potential rises steadily while " Therefore, I want to know, is it possible to couple the spot on the cathode-ray tubeisbeing a speaker or some similar device, from baby's room to pulled (by this very potential) across the screen. our living room downstairs, which will cut into the Quite simple, that.Now a gas -filled valve programme we are taking without the need of con- will suddenly short-circuitinternally due to stantly switching over to gramophone P.U. ? " lir_ the sudden ionisation of the gas, and the helium Thinking caps on, please. What about it ? How or mercury tube does this when the potential have you solved the problem at your house ? reaches a certain voltage.If the valve were without grid and grid bias, the potential As far as I can see the best way is for C. A. R. to across the condenser Cd. (whose capacity naturally controls the rate of charge and there- fit up an adaptor scheme that allows him to plug in fore the rate of rise of potential) would only reach about 25 volts before the valve shorted the output from the baby's loudspeaker mike --or, and discharged the condenser. better still, from a proper microphone (a cheap one That would not do for television. So the valve is kept back from discharging by the will do) via a small amplifier into the L.F. side of bias on the grid 0.This bias is set to allow the potential across Cd. (that is, across his set.I think he could arrange this all right, so anode A and cathode C of the valve) to reach any desired and predetermined voltage to that the adaptor could be plugged in to the L.F. drag the spot of the tube right across the full picture scan. valve holder following the detector (it's safer than At the end of the scan the potential should have reached a value sufficient for the valve trying to do it on the detector stage), the valve being plugged in again on top of the adaptor. to flash -over and thus to remove the pull on the spot.To ensure that the flash over What happens then is that you have two feeds takes place at the right moment a synchronising impulse is applied to the grid of the to the grid of that valve. The first one comes from valve in such a way as suddenly to make it more positive (to reduce momentarily the the detector of the set, and the other in parallel static negative grid bias).This at once lowers the impedance of the valve and the flash- comes from the output of the one valve amplifier over takes place. situated in baby's room, or else in the room down- Immediately afterwards the synchronising impulse is removed, the bias is therefore stairs, whichever is more satisfactory. fully applied again, and the condenser Cd. commences to charge once more-the next All you have to look out for is howling due to long scan has commenced. microphone leads.If these are well shielded, you 410 Popular Wireless, December 26th, 1936.

pantomime swords are tin things that bend double if you cut and come again ;they are SEEN ON THE AIR really quite dangerous articles. Periodical Changes Needed News and views on the Television Programmes by One or two other points about my studio visit.Viewers may have seen a board with our special radio -screen correspondent, announcements on it slowly rotate revealing a further announcement on the othet side.This L. MARSLAND GANDER rotation, like the turning of the pages of " Picture Page," is actually done by hand. One of these days there will be a mechanical I VISITED Alexandra Palaceagainthe The 'camera -man has to give his subject the device for it, I suppose. other night to seetheMarconi-E.M.I. cue, and there is a lag here that must some- Thereistalkof filming the permanent studio in action. Mr.Stuart Hibberd, how be " taken up." The effect on the home incidental features of " Picture Page," such the B.B.C.'s senior announcer, was taking screenissomewhat amateurish. Viewers as Joan Miller at the switchboard and the part in the programme-" Picture Page "- see Miss Cowell or Miss Miller, or whoever it " Warspite " boy bugler.The troubleis, and he confirmed my impression that the place may be, staring at them and waiting for the though, that such features should not be was very like a smaller film studio. starting signal. permanent but should be changedbefore Mr. Hibberd is by way of being an experienced Then the tops of artists' heads are occasion- thepublictire,admirablyasthey have film actor now because he has taken small ally cut off ;the other day I noticed a caption served the purpose up to the present. parts in about five productions.The last alluding to " Gaumont-British " News, the was a film of Britain's defences called " The second" i " having been omitted. Then Gap," in which he isseen announcing a there is the delay in getting plumb in the I had an agreeable surprise when Mr. Stephen coming air raid.He told me that the only centre of the screen ;the need for more rapid K. Thomas presented the Vic -Wells Ballet in essentialdifferencehe couldseebetween focusing.There must be a rigorous, searching " Facade."I am not a great advocate of television and film technique was that there examination of production methods-a tight- ballet by television, as I contend that the was no time for adequate rehearsal in the ening up, and a speeding up.Well, I suppose screen is too small to do it full justice.But television studio. itis easy to write and not so easy to do. thisparticulartransmissionwas anun- The control room, reached by a vertical When I saw members of the B.B.C. staff deniable success. iron ladder, conveniently overlooks the whole hareing about the studio with lines of care studio from an upper corner.Engineers on engraved on their faces I sympathised.Still, Items of Ideal Length the cameras are equipped with earphones television must be served.It will not wait. William Walton, the composer, conducted, connecting them to the heart of things in the " Picture Page," for which I have often first appearing on the screen. to conduct his control room. expressed my admiration, ran a little to seed workSiesta " as an introduction.Members on this occasion. There was a talk by Bertram of the Vic -Wells ballet are great artists.The Altogether A Busy Scene Mills' circus master which could well have been items are just about an appropriate length Only half the great studio was in use when I cut by half.A number of the other turns for television. was there.It was bathed in brilliant illumina- would also have been much improved by Afterwards Sophie Tucker came on the tion from a battery of flood -lights above and severe cutting. screen,an unusually important catchfor around.The microphone, suspended from a But Mr. Cecil Madden's nimble mind had television.She sang Eric Maschwitz's " These long boom, hung just out of " sight " of the devised several amusing features.There was, Foolish Things," but I heartily wish she had camera near the television subject's head. for example, the opening dialogue between not turned it into a slow monologue. Thus One of the use was on a trolly, two " schoolmasters," Will Hay and Ian Hay. rendered it was hard to credit that there is and was run backwards and forwards as it . Mr. Ian Hay was once a housemaster at Fettes, poetry in these lines. was necessary to vary the distance from the and hislatest comedy, " Housemaster," is subject. now running at the Apollo Theatre.Mr. Will * As in the Baird studio it was noticeable Hay's efforts to educate his scholars, fractious Miss Moira Meign's cookinglessonwas, that there were twenty or thirty people about, and ancient, are too well-known to need any to a mere male, slow.It was bad staff work mostly performers inPicture Page' waiting description of mine. to repeatitin the evening.The biggest their turn.Mr. D. H. Munro, the Productions effortofthe week was Mr. Cecil Lewis's manager, kept a stern eye on the flotsam and Armour With A Pocket ! anti-aircraft programme.He was rewarded jetsam like myself to see that we did not I liked best, however, the effort of Mr. for a tremendous effort of organisation by trip over cables or impede the passage of the Samuel Rex, maker of pantomime swords and success for the first outside television broad- trolly backwards and forwards. armour.Mr. Rex is in deadly earnest about cast at night. A pity that the R.A.F. bomber It was most interesting to be able to see the his strange job-make no mistake about that ! which was to have added to the realism of the - picture,as televised, on a receiver in the He claimed that his ancestors had made occasion could not take off owing to heavy studio.I cannot -help thinking, with due swords for Julius Caesar's army, but that rain and fog. deference to the overworked producing staff, things aren't what they were in his profession. To the Saturday variety programme Harry that there is need for a tightening up of the True, a young woman did ask him to make Pepper and Doris Arnold with their two pianos system of cues and other details which will her a suit of chain mail the other day, but she act made a most entertaining contribution. tend to make for more finished production. disgusted him by wanting a pocket for a I was a little bored with Tony Sympson's For instance, whenever Elizabeth Cowell cigarette case in it.Mr. Rex showed us a pretended struggles to express himself in a came on the screen to announce, or Joan good many examples of his art.Cromwell's foreigntongue and disappointedthatho Miller, the telephone girl, was seen, there was an Ironsides and Arthur's Knights lived again should revive a song as ancient as the egg appreciable pause before either began to speak. inthestudio. Don'tthinkthatthese with which it dealt.

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yt .* " insides " of a radio receiver, because there are no working parts, can be left indefinitely TECHNICAL JOTTINGS without attention. Items of interest to all " Working " Parts By Dr. J. H. T. Roberts, F.Inst.P. It is not even strictly true to say that *. there are no working parts because, of course, there are rheostats, potentiometers, THE voltage across the anode of a valve, variable condensers and so on, which are when using a high-tension unit,is " working " parts in the true sense of the Up-to-the-minute news concerning the greater when the filament is cold than word. and although perhaps they do not radio industry when the filament is heated, for the very needoiling,likeothermachines,they simple reason that in the former case you get nevertheless suffer seriously from accumu- the full voltage on " open " circuits, whereas lations of dust and dirt. AN INEXPENSIVE S.G.3. in the second case, when the filament is Dust settling over the surfaces of even ABATTERY S.G.3, priced at 6 guineas heated, you have current flowing and a " stationary " components such as trans- complete withbatteries,isbeing drop in the voltage. formers, chokes, fixed condensers and so on, marketedbyBrowningWireless Inahome -constructedreceiverthe can cause serious trouble, owing to the Manufacturers.The set is fitted with an difference between the high-tension voltage absorption of moisture and to gradually 8 -inchpermanent -magnetmovingcoil on open circuit and that on closed or operat- increasing electrical leakage, whilst in the speaker, and the circuit used is of the all - ing circuit conditions is sometimes over- case of the " moving " components, such as pentode type. looked, with the result that the condensers variable condensers and the others men- Housed in a walnut cabinet, this " Brown- are selected on the basis of the anode tioned above, the same trouble occurs to ing " model is provided with gramophone voltages to be dealt with under working an even greater extent. All these bad effects pick-up sockets and sockets for an extra conditions. In many sets, both high- are worse in the high-frequeney part of the loudspeaker.An additional aerial socket is tensionandlow-tensionvoltagesare circuit than in the output end. fitted in order to reduce interference from switched on by a single switch, and this Droitwich, thus improving the reception ofmeans that the full H.T. voltage on open Dust -Proof Cabinets ? other long -wave stations.The price of the circuit is switched on to begin with, this In general a manufacturer takes precau- receiver without batteries is 5 guineas. voltage gradually falling as the filament heats up and the anode current begins to tions to enclose as effectively as possible any * apparatus which must be kept free from flow. dust, and perhaps that is why many people ALL -WAVE CONSOLE The Enemy Within imagine that the inside of a radio set needs The high performance of the McMichael In spite of all the instructions which we no attention. But if you think about it for Model 362all -wave A.C.superhet has read about keeping the components inside a moment you will see that it is practically resulted in a large number of requests for the receiver free from dust. I don't suppose impossible to make the inside of the set an all -wave console of similar efficiency. one set in twenty ever receives any sort of dust -tight, there are so many parts that have InconsequenceMcMichaelhavenow attention in this direction.How many to be left open. For instance, a large space released a console version of the Model 362, times have you examined a friend's set and has to be left open for the sound to come the price being 17i guineas. found it absolutely covered with dust ; out from the loudspeaker, and again ventila- The consoleincorporates the5 -valve how many times have you examined a set tion has to be provided for so as to allow the 8 -stage chassis as used in the existing table and found it all spick and span and as clean heat generated in the valves,rectifiers, model,thewavebandscoveredbeing as it was when it was first made ? and so on to escape.This ventilation in 18.6-51metres, together with the usual Well, it doesn't matter so much about itself is a fruitful source of dust because it medium and long wavebands.The cabinet the other sets, but what about your set ? draws in the dusty air from the room, the issolidly built from figured and inlaid Do you go over your set regularly once a dust thus being deposited on everything walnut, with a speaker surround of oxidised month and keepitabsolutelyclean ? inside the cabinet.In the case of a radio - copper and is polished to a high piano - Many people who fully realise, for example, gram, you have the gramophone motor at finish, as in the case of all McMichael 1937 the importance of keeping the working the top, with lots of open spaces through models. parts of a motor -car or ' other machine which not only dust but actual dirt of all regularly cleaned out, seem to think that the (Continued overleaf.) NEW H.M.V. SET The latest H.M.V. release is an all -wave superhet for battery users.Incorporating four valves, it is fitted with A.V.C., and on Eleriatite SPECIALITIES the short-wave range covers from 18-50 For Better Christmasand metres.The output is approximately 11 watts undistorted, while the H.T. con- RECEPTION sumption is given as 7 milliamps.Other 1Rew dear This is the time when the home radio has a special appeal.If you want refinementsareathree -positiontone to get the best out of your set, then insist on Aerialite specialities-you'll. control and concentric fast and slow motion be amazed atthe improvement inthe quality of the reception. tuning controls.The priceof theset, Use AerialiteH.T.Batteries.AerialWires. ALL -WAVE whichisknown, asthe Model166,is AERIAL Kit,etc., etc. 13 guineas. AERIALITE " TRAPEZE " AERIALS * * * No danger. Needs no mast. Complete in carton with bracket fittings and 50 ft. G.E.C. GEAR FOR GOLD COAST Aerialite insulated down lead. Price 9/- SHORT-WAVE ADAPTORS The Crown Agents for the Colonies have Two types : AER1ALITE " LITTLE MARVEL " I. For coupling to input of S.C. Re- AERIAL ordered a complete radio relay equipment ceiver. Range16-52 metres. A Junior version of the " Trapeze." from the G.E.C.This equipment is to be 2. An Autodyne as above with Ultra.. An efficient no -pole type aerial. Com- slow-motion dial covering two ranges plete in carton with bracket fittings used for the extension of the Gold Coast -13-27 metres and 27-85 metres. and 40 ft.Aerialite insulated down Colony broadcast relay service to Koforidua. Price : No. I, £2 7s. 6d., and with S.M. lead.Price 419. Theapparatuscomprisestwospecial dial (No. 2) £3 3s.Fitted in a minute The new " RADIAL " AERIAL- short-wave receivers with associated power by anybody. No-mast type -3/6. amplifiers for direct operation on the 230 From your dealer-or direct, post free. D.C. supply available. This order is the fifth of its kind for the AERIALITE LTD. Gold Coast Colony and, in all, the G.E.C. JUNCTION MILLS, ASHTON-UNDER-LYNE have supplied complete equipment for some 3,000 subscribers in this Colony. 442 Popular Wireless, December 26th, 1936.

TECHNICAL JOTTINGS anode -benddetectionwas regardedas superiorin many waystoleaky -grid, (Continued from previous page.) but the introduction of the tone -correcting transformer, and certain other factors, has kinds canfallinto the works (usually put leaky -grid detection back on the map. 1936 including a plentiful supply of gramophone Flat Tuning has seen a good deal of thought needles).I came across a set the other day andcare expended overcircuits. Nine which was giving trouble due to oscillation, When dealing with a set with " flat " and on examining it found that not only was tuning, you can " off -tune " to an appreci- times out of ten the set -designer has sped - it absolutely choked with dirt and dust able extent on either side of the true fleda J.B. Condenser or Dial.More and inside, but also there must have been scores tuning point without very much effect on more constructors are discovering that for of gramophone needles lying all over the the quality, or perhaps on the volume. superlativeperformance andreliabilitya place, between condensers and chokes and If,however, the setis very selective, J.B. Component cannot be bettered. in contact with H.F. conductors. The obviously as soon as you depart from Our Service has always been at the dis- surprising thing was there had not been an the true tuning point, you will get not actual short circuit ! only a very considerable drop in volume, posal of constructors and we shall be pleased but also a greater or less amount of dis- to assist you with any of your set problems, The Monthly " Once-over "' tortion. Consequently, there is no difficulty small or large, during At least once a month you want to " go in knowing, with a sharply tuned set, over " the inside of the set and make sure when the setisaccurately tuned to a that everything of this kind is completely particular desired station. removed. You can't dust it with an ordinary When the set uses automatic volume 1937 duster, but a very soft camel -hair brush, or control, however, you get an effect which something of that kind, usually suits the has sometimes been describedashalf- purpose, and with this you should go care- way between that of a flat -tuned set and fully over the whole of the components and that of a very selective one.The set all the spaces between, making sure that behaves in some ways like a flat -tuned nothing has been allowed to lodge between receiver,but, in addition, you get the them.I need hardly say that before doing distortion effect when moving away from anything like this you should completely the true tuning point as you do with a disconnect the set from the mains, or even sharply tuned receiver.Ishould say, the batteries if it is a battery set, so as to however, that this effect may not be so avoid any possibility of electrical trouble. noticeableaswherethereisactually CONDENSERS Variable condensers should not be tampered sharp selectivity. with whilst in position, and it is usually AND DIALS quite impossible, with any sort of safety, Amplification Control has JACKSON BROTHERS (London)Ltd., to insert the proverbial pipe -cleaner between Automaticvolumecontrol the 72, St. Thomas St., S.E.1. Telephone:Hop1837 the vanes unless the condenser is removed essentialpurposeofmaintainingthe from the set. volume at a reasonably constant level, notwithstanding changes in the strength Mind Soldered Connections T. of the incoming signals, or perhaps, to be What you can do, however, is to blow more accurate,notwithstanding changes air through the condenser and this can be in the strength of the signals as applied ARadio mechanic named done by means of a short length of rubber to the detector.What happens, as most Hyde tube, one end held in the mouth, taking people know, is that when the strength of For a " fault -finder's" job care not to blow any moisture into the the signals reaching the detector goes down, once applied. condenser. When using the camel -hair the variable -mu valve does its stuff and "I'll be all right," he mused; brush for removing dust in other parts of increases the amplification, and vice versa. " Where no FLUXITE'S been used the set, see that you don't dislodge any of You willsee now why it is that when I could always find fault if the conductors from their terminals, or operating a set in which automatic volume I tried." that you don'tstrike and break any control is used you can get off the tuning soldered connections. point without the volume changing very See that FLUXITE is always by you-in the house -garage-workshop-wherever speedy soldering You will be surprised what a difference greatly, and that is how it comes about is needed.Used for 30 years in government works it makes to the functioning of a receiver that the set behaves in some ways like and by leading engineers and manufacturers. Of when it is kept quite clean and free from any a broadly tuned orflat -tunedreceiver, Ironmongers-in tins, 4d., 8d., 1/4 and 2/8. whilst the distortion which occurs when you Ask to see the FLUXITE SMALL -SPACE SOLDER- dust or foreign matter inside. A modern set ING SET-compact but substantial-complete with is so highly efficient, and everything so go off the true tuning point is not of that full instructions. 7!6. accurately balanced electrically, that the awful kind you usually get with an ordinary Write for Free Book on the art of " soft " soldering and ask for Leaflet on CASE- presence of dirt in the set will make quite an sharply tuned receiver without automatic HARDENING STEELandTEMPERING appreciable difference to its operation, and volume control. TOOLS with FLUXITE. I can assure you that I am not exaggerating when I advise you to give it the monthly Watch Condenser Specifications wroheelsund NOT TO CYCLISTS keep round d once-over as described above. When you are building a set, it is better unless the spokes are tied with fine wire to be over -cautious with the specification at the crossings AND SOLDERED. This Tone Correction of fixed condensers, by which I mean that makes a much stronger wheel.It's simple -with FLUXITE-butIMPORTANT. I have been asked] a number of times-itis better to use a condenser specified whether a tone -correcting transformer can to stand a higher voltage with safety than The FLUXITE GUN be used as well with anode -bend detection one with a specification on the low side. isalwaysreadytoput detection. acondenser which Fluxite on the soldering lob as with leaky -grid If this If you incorporate instantly.A littlepressure transformerisusedwithanode -bend has not a sufficiently high voltage specifica- places the right quantity on detection there is a tendency to increase tion, you are only asking for trouble. therightspot,andone charging lastsfor ages. the harmonic distortion.If it is used with Remember thatthecondenserhasto Price 1 6 a leaky -grid detector, however, provided stand not only the peak voltage of any the detectorisoperated under correct A.C. which comes along, but also " surges h ALL MECHANICS HAVE conditions, the tone -correcting transformer of current which take place owing to can be made to give excellent results. accidentalcircumstancesfromtimeto With the anode -bend detector there is, time.I think it is not exaggerating to say as indicated, a certain amount of harmonic that a condenser sometimes has a voltage FLUXIT distortion, owing to the fact that the momentarily applied to it perhaps two or rr SIMPLIFIES ALL SOLDERING so-called " straight " part of the curve of three times the steady voltage for which ILcXITE. the valve is not actually straight at all. it is ordinarily intended. A single surge is This recalls the fact that, not so long ago, quite capable of puncturing the insulation. Popular Wireless, December 26th, 1936. 443

A "RECORD" CHRISTMAS (Continued from page 43g..)

The music goes round and round, wrote some lyric writer. He was a prophet as well as a humorist.If there ever was a truer saying as applied to dance music I have yet to hear it. Do you remember a certain mournful Body and Soul ?Yes ?Well, you can refresh your memory and your earsifyou wish with Decca F 6143. Ambrose and his Orchestra have revived the old number. I wonder why ?Incidentally Bye, Bye, Baby is to be heard 'on Regal Zono MR 2214, played by Charles Barnet's band. Knock, Knock IWho's there ?Sarah !Sarah Who ?Serenade in the Night.Sorry for this intru- sion into a more or less serious review.But that very " Knock, Knock " is one of Henry Hall's star, wisecracks when he broadcasts the "Knock, Knock" number. And I have quoted it to remind you that in spite of all the broadcasts, the recording and even the office boy's whistling, the number Serenade in the .Night is still being given hard wear and tear. I have nothing against it as a number, but I wish they would give it less strenuous use. However, it has been recorded again, this time on Rex, and 'is sung really excellently by Jack Payne's vocalist, Ralph Silvester. A Haunting Numbef I said a few rude remarks about Shoe -Shine Boy the last time. I was criticising the lyric, and though I still do not like the scanning of the words I must take off my metaphorical hat to Nat Gonella for making a really fine record of the haunting number. Yes, itis haunting if you take no notice of the words, though Nat certainly does his best with them.The record is a Parlophone, and I advise everyone who wants a semi -hot recording of the number, yet a recording that does not go all gaga with trumpet breaks and what not,to hear it. Nat Gonella has put just the right interpretation into Shoe -Shine Boy, and I certainly consider his one Some of the guests who were present at Jack Hylton's party at the H.M.V. recording studios.Seen in the of the best records of that number that I have -photograph are Jack Hylton's Swing Quartet, Tommy Handley, Tom Webster, Freddie Fox, Jack Harty, heard. Nelson Keys, Peggy Dell, Hilda Mundy, Billy Caryll, and on the right Jack Hylton himself.The party By the time you read this, though at the time of was recorded on H.M.V. C2883. writing there is a lull before the storm in the gramo- phone world, your record dealer will be inundated with all manner of Christmas records. H.M.V. alone are bringing out eighty. MEET 'THE BROADCASTING attractive to look at and pleasant company For once there will be few carol records.There at breakfast. will,however, be a medley of Christmas Songs played by Alfredo Campoli.This year is a year of BACHELORS " Up to the present," went on Ronnie, medleys. Peter Dawson is doing a medley of nursery (Continued front page 431.) " I have had to forgo domesticity and have rhymes called Uncle Peter's Children's Party. Should most of my meals out.I've made quite a amuse the kiddies..41 Mother's Knee is another medley of lullabies sung by Essie Ackland. study of it, too, getting a wonderful list of attribute she must have is a sense of humour, jolly good eating places. My favourite Six Mickey Mouse Records particularly when things go wrong. I would haunt is a little pub, only a few minutes Cicely Courtneidge and Jack Hulbert are providing want her to have simple tastes-the ability from the B.B.C., where you can get the best a medley of Our Greatest Successes, and Roy Fox and to be happy in an armchair with a good book 11:s protegee Mary Lee will give us a 1936 Hit Parade. -but, at the same time, there must be a home cooking in London.I think these That's not the end of it by a long chalk. There is to things are important to a bachelor who, be a Strauss Waltz Medley, a re-recording of famous strong practical side of her nature ;she dance numbers played by famous bands to make a would have to be resourceful, drive a car, spending perhaps nearly a quarter of his dance record medley.The bands include Jack life in restaurants and snack bars, should Hylton, Ray Noble, Benny Goodnian.And, don't and do things like that,. reduce the tracking down of such places to forget Jack Hylton's Party.The number of this " And I daresay if I found a girl with all record is given beneath the photograph on this page. a fine art." The children will welcome the 10s. 6d. Mickey Mouse those attributes she'd hate the sight of me !" Silly Symphony album containing six records. Think That gifted young man, Ronald Hill, " So Generously Equipped " of it, an hour's entertainment on record with Mickey shares one of Harry's objections. Mouse ! The album contains the three Mickey records Gordon Little has succeeded in resisting that have already been published, and three new ones. " I have no intention of marrying just the perils of roughly twenty-eight springs. For the serious music -lover there is the re-recording yet," he told me, " as my work keeps me And for a young man so generously equipped of Caruso singing the Flower Song from " Carmen," and the Farewell, Dear Mother from " Cavalleria away from home so much that it would be as he is with looks, talent, charm of manner, Rusticana." This is said to be the finest Caruso hardly fair-or safe !-to leave a wife alone a sports car, a cottage in the country and a recording yet done. For the first time for many years a full-length for such long periods.If she got into half share of an aeroplane, this is indeed a symphony has been recorded.It is the Seventh, by mischief I would naturally grieve ;if she feat ! Beethoven, and is played by the New York Phil- didn't I should feel ashamed of being the " But if and when I do marry," avowed harmonic under the baton of Toscanini.There are five records in all, and the playing of the last move- object of such unmerited loyalty !When Gordon over lunch (at Ronnie Hill's pet ment is superb. eventually I do marry, it will be someone pub previously alluded to), " I shan't care Again we have a recording of Schubert's Unfinished. Itis played by the Vienna Philharmonic under entirely outside the business of radio or the whether my wife is blonde or brunette so Bruno Walter-a Viennese orchestraplaying a theatre-a sharp critic, as a lot of home long as she possesses the supreme quality composition actually written in Vienna. flattery is cruelly misleading.She would Make sure you have a merry record Christmas. in a woman of being a good sport ;also, Here's good health and happiness to all of you. have to be a magnificent cook, civil and she must be essentially feminine-not in K. D. R. efficient on the telephone and, above all, (Continued overleaf.)

tree Zuwiits &cc:1111p froma jramotts Cibotwe fw The Managing Director and Staff of the Peto-Scott Co., Ltd., extend to their thousands of customers, past and present, in all parts of the World, sincere wishes for a Merry Christmas and a Bright and Prosperous New Year. PETO-SCOTT The Most Famous Name in Mail Order Radio.

131175sol6 a n r igh HEoi L3o248n PETO-SCOTT Co. Ltd., 77, CITY RD., LONDON, E.C.1. 9 EST. 1919 MI.i40%!ii441P§AtANkiliWit.4%tikA,ZAO!`:i4.141.1.WAtP§tgl'SNI:140§41:40§41AikittNVIV:i4M 414 Popular Wireless, December 26th, 1936.

MEET THE BROADCASTING MISCELLANEOUS ADVERTISEMENTS RECEIVERS, COMPONENTS AND BACHELORS 3d. per Word ACCESSORIES 6d. Per word for first words in heavy type Surplus, Clearance, Second -Hand, &c. (Continued from previous page.) 6/- per fine for displayed lines (12 pt. type) (Continued) the submissive, narrow, prudish way, but Minimum Charge 3 - feminine in the sense of possessing the most Remittance must accompany order. SOUTHERN RADIO'SWireless Bargains;all goods noble instincts, tenderness, maternal feeling, guaranteed and sent post paid. Advertisements for these columns are G.E.C.3 -valveBatterySets," Battery Compact understanding, a quiet wisdom and the accepted up to first post WEDNESDAY Three," with 3 Osram valves, moving -coil speaker rest of all the fine qualities that make up MORNING for the following week's issue. inbeautiful bakelite cabinet, brand new, in sealed All communications should be addressed cartons,fully guaranteed ;50/- each (list65/10). theideal woman whom idealistshave to Advertisement Department, "Popular Wireless," John Carpenter House, John SPEAKERS,-CelestionSoundex permanent magnet, visualised throughout history. 101- ; Telsenpermanentmagnet,with10 -ratio " I want her to be cheerfully informal but Carpenter Street, London, E.C.4. transformer to suit ally receiver, 12/6 ;Telsen loud- speaker units, 2/6; allbrand new and in sealed not agonisingly bright-particularly in the cartons. early mornings !And, as well as being RECEIVERS, COMPONENTS AND COILS.-Telsen,iron core, W349, Midget size, 4/-; thoroughly domesticated I would want her ACCESSORIES Type W478 (twin), 9/- pair ;W477 (triple), 16/- set; Surplus, Clearance, Second -Hand, &c. Type W476 (triple superhet selector and oscillator) to be capable of looking after telephone 16/-set,all ganged coils complete on base with calls and keeping me up to my appoint- CONVERSION UNITSfor operating D.C.Receivers switch ;TelsenI.F. transformer coils, W482, 5/-; ments.She'd have to be rather a maid of from A.G. Mains, improved type, 120 watts output at Telsen dual range aerialcoils,withaerialseries E2 : 10 :0. Sendforour comprehensivelistof condenser incorporated,W76, 4/- ;Telsen aerial all work and very keen on sport, but not so Speakers, Resistances and other components. series condensers with shorting switch, 2/-;Telsen obviously sporty that her gentleness and WARD,46,FarringdonStreet,London,E.C.4 L. F.transformers, Type R.G.4(4 to 1),3/-; all femininity suffer as a result of her en- Tele. HOLborn 9703 brand new, in sealed cartons. thusiasm. Someone who resembles my SALEOF NEW SURPLUS RECEIVERS,Etc. MICROPHONES.-Ace(P.O.) microphones, complete G.E.C.B.C./3480,8-v. A.C.Superhets£7/l5/-, with transformer, ready fo( use with any receiver, sister as closely as possible ! " Listed21 Gns.3435/M.V.,6-v.A.G.Superhets 4/6 each ;Ace concert microphone, complete on " And someone," interpolated Norman 66/15/-, Listed £14/14/-.D.C./A.C., Models 66/151, chromium stand with volume control, ready for use 5-v.models £5/19/6.4-v.models 64/19/6.6-v., with any receiver and amplifier, 11/, Long, who entered at this moment, " who A.G., 3550/ R.G.,Radiograms £14,Listed 24 gns. RESISTANCES.-Tru-ohrn1 -watt, colour coded and resembles my sister for me, if you please. Lampex 4-v.A.C.Receivers 63/15/-. 55/-. marked, 36 assorted capacities on card ;6/- per card. When I find someone who understands me D.C., 45/-.Marconi 248, 2-v.Battery Sets 35/- AMERICAN VALVES.-Afull range of valves for all 3-v., 70/-.Ready Radio Meteor S.G.-3 Kit Sets Ct. as well as my sister does, I daresay I'll Magnavox 236, P.M., M.G. Speakers 101,Celestion American receivers;6/- each. want to marry her. But if she knows me as " Soundex " 10/,A.C. Eliminators 61, D.C. (to/-. HEADPHONES.-Lightweight headphones,double 3 -gang Condensers4/6, etc.TradeSupplied. pole type, 4,000 ohms, each ear piece ;3/-pair. well as my sister I shouldn't think she'd Collins, Riversley Road, Nuneaton. REPAIRS.-Allytype ofreceivers. American, want to !I've managed without a wife for British, etc., repaired by expert staff. HEADPHONES, Brown, G.E.C.,B.T.H.,Nesper, WEHavePurchasedtheCompleteComponent forty-two years and I've no doubt that I'll Sterling, Marconiphone, etc.From 2/6 pair.Postage Stock ofa Well-known Radio Dealer and Manu- be able to survive the absence of such a 6d. List free. facturer, and we are offering the complete stock in partner as I grow older.I now live with my CRYSTAL SETS. Complete.Guaranteed.Burne- parcel lots as under Jones,5/6. Ditto, double circuit, 8/-.Large P.O. 5/-Parcel, containing components to the value of at sister in a flat in Sydenham, and it's the type,10/-. Crystal detector, complete parts,1/-. least20/-,comprisingchokes,resistances,coils, perfect life." Sensitive permanent detector,1/6. PostRadio, switches, condensers, wire and circuits, 5/- per parcel. Above I have presented the opinions on 183, Caledonian Road, London, N.I. 10/- Parcel, containing components to value of at RADIO BARGAINS. Amazing prices. All -wave least 45/-, comprising variable condensers, screened marriage of five typical bachelors in the A.C./D.C. Table models 6605/-.Halcyon A.C.7, chokes, switches, resistances, screenedcoils,wire, broadcasting world of to -day. What do the 67/7/,A.C./D.C.,Listed 14Gns., 67/7/-. Mains circuits, etc., etc. ;10/- per parcel. receivers from 65.Send Stamp for list unrepeatable ALLArticles Included in These Parcels are Brand other bachelors think ? And when, if at all, bargains.English, American valve replacements. New and Modern. will they cease to be bachelors ?There's Full Stock all -wave Ferguson Models. SOUTHERN RADIO.-Branches at 271-275,High Brian Lawrence, Freddie Latham, Arthur LITTLER,the Midlanddealer,2,BarrasLane, Rd.,WillesdenGreen,N.W.t0 ; 46,LisleSt., 'Young, Bryan Michie, Len Bermon, and COVENTRY. London, W.C.2.All mail orders to 323, Euston Rd., BANKRUPT BARGAINS.List free.Battery 3-v London, N.W.t. plenty of others. all -wave H.F. pentode, detector and pentode sets SOUTHERN RADIO,323,EustonRd.,London, with M.G. speaker and valves, 79/6d.Halcyon A.C. N.W.t (near Warten Street Tube).'Phone :Euston superhets, A.C-3 £6. A.C.7 7 gns.Ormond 3-v. 3775. H. F.pentodetransportableswithM.G.speaker MY TELEVISION ADVENTURES 57/6d. Pilot,Ferguson and Truphonic all -wavers, PLEASE BE SUREto mention ." Popular Wireless " trade supplied.Large stock components, valves, Thanks I (Continued from page 427.) etc. All new goods.Butlin, 6, Stanford Avenue, when communicating with Advertisers. Brighton. But I can see that television is going to A THOUSAno BARGAINS MISCELLANEOUS make the " fade-out " a real art, and B.B.C. MAINS TRANSFORMERS, M.C. SPEAKERS, MAINS VALVES, SHORT-WAVE GEAR, CABINETS, Etc. WANTED,Modern usedRadioSets,Short-wave producers and comperes will have to find a parts and Adaptors.Speakers, Eliminators, Meters, way of linking up a programme without PREMIER SUPPLY STORES Motors and Pick-ups.Spot cash paid.Bring or the screen just going dark-or artists sidling 20-22,HIGH STREET, CLAPHAM, S.W.4. send.University Radio Ltd., 82, Hampstead Road, out of the picture. SEND 3d. STAMP FOR CATALOGUE. London, N.W.t. The whole thing's so experimental yet that it's not fair to be critical.But I can The Ideal Book for see what a terrific strain televising is going ELECTRADIX BARGAINS to be for many radio stars.I doubt if even COIL TURN COUNTERS for check- Garden Lovers film stars will stand up to the strain. ing the number of turns up to 9,999 on dial.Soiled, 1,3 each. Not only does your voice have to be BELL SETS. BestBritishTrembler, 2/- each.Porcelain super -grade Pushes, Inthisprofusely - perfect, as it should be for radio, but your liaillkosissbankrupt2/6linefor 8d. Flat Brass. illustrated book the 1/6. Door Barrel,allbrass,2/6. Twin lead -covered mannerisms must stand that crucial close- bell wire, id. per yd. Indoor bell wire, single. 100 yds. gardenerwillfind 1/6; twin, 3/-.Transformers for ringing 100-v. A.C. valuable and up test every minute of the time. 2/6; 220140 A.C., 3/9. authoritative in- For years we've been saying that radio SPEAKER BARGAINS.- .00. ad.... formation ongar- Genuine bargainsin high-grade is harder and more exacting than making moving -coilspeakers byfamous dening matters: makers. All new and offered at less suggestions for the records or pictures, because your whole than half price.Quality reproduc- cultivation of tionofspeech and music guaran- flowers,fruitand reputation depends on a broadcast, whereas teed. you can always re-record or do a film re -take MAINS ENERGISED vegetables, a !I d SPEAKERS.- 6in. R. & A., articles on original if things go wrong. 2,500ohms,withspeechtrans- gardenfeatures. former, 7/6; Hegra, 9in, with transformer, 12/6; Sin. Now there'll be the anxiety of extra with transformer, 15/-. Magnavox, 6in. type, " 144," planningattliim- 2,500 ohms, 12/6; R -R., 8in. cone, 1,000 ohms,10/6. proving the garden, rehearsals, more study, necessity of being A.C. MAINS SPEAKERS. WITH RECTIFIERS. and the selection of 100/250 volts; Ilin. cone with transformer30/,Jen- plants. Buy your word-perfect,photogenic,andof not sen, 220-v., fin- cone and transformer, 251.:100-v., ditto, 7in. cone, 201-7 100-v. A.C., Biu. cone with trans- copy now. letting an intonation or a facial movement former, 211, betray you when the television's on. ALL -WAVECRYSTALSETS for plug-in coils, 2 tuning condensers, semi -perm. detector,'7;6. In spite of all this, I enjoyed every minute HEADPHONES.-Sullivan 120 ohms, 2/9. Ericsson and others,2,000 ohms, 4/6.Single highres.ear- of my broadcasts, and, for the time being pieces. 2/8. POPULAR GARDENING I'm going back to radio and recording, 1,000 giftsinour latest Bargain List "P." free feeling that I've learned something in nerve ELECTRADIX RADIOS OfanallBAolsexernsts control,- concentrationandprogramme 218, Upper Thames Street, London, E.C.4. ANNUAL 2'6 presentation. Phone: Central 4611 Dedember 26h, 1036. POPULAR WIRELESS iii SHORT-WAVE STATION LIST Wavelengths and other details of many of the stations you can hear on your short-wave receiver

Wave- Wave- Station. Call -Sign. Power. Station. Call -Sign. Power. length. length. 13.93 Pittsburgh W8XK 40 31-07 Lisbon CT I AA 2.5 13.93 Daventry G S J 10 3113 Rome 2 R 0 25

13.94 Wayne, New Jersey W2XE 1 31.27 Radio Nations H B L 20 13'97 Daventry G S H 10 31.28 Philadelphia, Pa. W3XAU 10 15.93 Bandoeng, Java P L E 60 31.28 Sydney VK 2 ME 20 16086 Daventry G S G 10 31.28 Eindhoven P C J 20 16.87 Bound Brook W3XAL 35 31.32 Daventry G S C 15 16.88 Huizen PHI 23 31.32 Lyndhurst, Australia VK 3 LR 16.89 Zeesen D J E 5 31.32 Buenos Aires L R X 5

16 - 89 Wayne, New Jersey W2XE 1 31.35 Millis, Mass. WI XK 10 19.52 Budapest HAS 3 20 31.36 Bombay V U B 4.5 19.57 Schenectady W 2 XAD 18 31.38 Zeesen D J A 5 19.60 Daventry G S P 10 31.45 Zeesen D J N 5 19.62 Buenos Aires L R U 5 31.48 Jeloy LKJ 1 19.63 Zeesen D J Q 5 31.48 Tokio J Z I 50 19.65 Wayne, New Jersey W2XE 31.48 Schenectady, New York W 2 XAF 30 19.66 Daventry G S I 10 3F55 Melbourne, Australia VK 3 ME 1.5 19.68 Radio Colonial, Paris TPA 2 12 31.55 Daventry G S B 15 19.71 Eindhoven P C J 20 31 -58 Rio de Janeiro PRF 5 5 19.72 Pittsburgh W8XK 40 32.88 Budapest HAT 4 5 19.74 Zeesen D J B 5 38.48 Radio Nations H B P 20 19.76 Daventry G S 0 10 46.52 Barranquilla HJ 1 ABB 1 19'8 Tokio J Z K 50 48.78 Winnipeg CJRO 2 19.82 Daventry G S F 10 48-86 Pittsburgh W8XK 40 19.84 Vatican City HVJ 10 49-02 Wayne, New Jersey W2XE 22.00 Warsaw S P W 10 49.10 Medellin, Colombia HJ 4 ABE 22.94 Suva, Fiji Islands V P D 4910 Daventry G S L 15 24.52 Reykjavik T F J 7.5 49.18 Chicago,Ill. W 9 XF 10 25.00 Moscow R N E 20 4918 Bound Brook W3XAL 35 25.23 Radio Colonial, Paris TPA 3 12 49.20 Johannesburg Z T J 5 25.27 Pittsburgh W8XK 40 49.26 Hong Kong ZBW 2 2 25.29 Daventry G S E 15 49.50 Philadelphia, Pa. W3XAU 10 25.36 Wayne, New Jersey W2XE 4950 Cincinnati W 8 XAL 10 25.36 Lisbon CT 1 AA 2 49.59 Daventry GSA 15 25.38 Daventry G S N 15 4967 Pernambuco PRA 8 3 25.40 Rome 2 R 0 25 49.67 Miami W 4 XB 2.5 25'43 Tokio J Z J 50 49.67 Boston, Mass. W 1 XAL 10 25.45 Boston, Mass. W 1 XAL 10 49.83 Zeesen D J C 5 25.49 Zeesen D J D 5 49.85 Bogota, Colombia HJ 3 ABH 1.6 25.53 Daventry G S D 15 50.00 Mexico City XEBT 25.60 Winnipeg CJRX 2 50.00 Moscow R W 5 9 20 25.60 Radio Colonial, Pans TPA 4 12 50.26 Vatican City HVJ 10 29-04 Ruysselede, Belgium 0 R K 9 51.28 Maracaibo, Venezuela YV 5 RMO 29.24 Bandoeng, Java P N 3 51.72 Caracas, Venezuela YV 2 RC 1 30.43 Madrid E A Q 20 70.20 Kharbarovsk RV 15 20 iv POPULAR WIRELESS December 26th, 1936.

For Those Who Play Golf- and For Those Who Don't ttr ry orCARD GOLF

Kargo as a card game has an individuality all its own, a novelty, a freshness and an interest 'that never fail.It can be played by two, three or four players ; there are all the hazards of golf, all the thrills of driving from the tee and putting on the green, of being bunkered or stymied, and yet you never leave your own home. . The pack consists of 53 cards,helpful hints explaining the play being given where necessary so that the game can be played easily, without constant reference to the rules. A round of card golf can be enjoyed at any time in any weather in any place. You:don't need to know anything about golf-just a few simple terms to understand and a rattling good card game isyours to command. f/ Kargo is a game of golf in which there t\is no club subscription, no lost ball, no clubs to buy, but One smallinitial Distributors: outlay of 2s. 6d. and no further expense east ellBros., Ltd., no matter where you play or how often. ,Itanufacturers of PrhrsStationery.

Sold by gall Stationers, Stores, . H. Snzith C.)- Son's (Ind Boots' Stationery Branches.

Printed in England and published every Wednesday 'by the Proprietors, THE AMALGAMATED PRESS, LTD., The Fleetway House, Farringdon Street, London, E.C.4. Advertisement Ottices :John Carpenter House, John Carpenter Street;- London, RCA: Registered for transmission by Canadian Magazine' Post.-" Subscription Rates : 'Inland and Canada, 174 per annum.Abroad (except Canada), 19;6 per annum.Sole Agents for Australia and New Zealand :Messrs. Gordon & Gotch. Ltd. ;and for South : Central News Agency, Ltd.Saturday, December 26th, 1930 S.S.