Blueprint Section Every Month

October Radio Age 9 Tube Super 1926 fI. Converting 9BHX to Crystal Control fI. Survey of Power Su pply Devices

Com.plete Broadcast List and Log 'In Each lssue . ~ $13 2z.2 ~~~;::rzs::~~~~~ioar~dT~b~li~rJ~i complete with Loud Speaker and all accesso_ ries.

Some People Will never Learn­ The Truth About Radio ANY a new radio will perform perfectly. Whether it con­ Mtinues to do so or not will depend entirely on one thing-the very truth that is seldom discussed. Do you drive a car? wrong. They will be serious to you and almost as serious to the handy Don't little troubles happen man who can fix all radios but- occasionally? Such troubles will mean just a few Do you depend on a handy seconds' time to a factory trained man for service or do you pre­ service man who knows that make of fer a mechanic who has been fac­ radio as he should. tory trained on your make of car? While radio is rather a new in­ dustry, even now there are 4364 Experience no doubt. proven has~ factory trained Ozarka service men­ to you that men who know all about let us give you the name and address all makes of cars generally don't $215 g~~~:c~~ast~l: 5aT:b;M~~I~~~ltJ of the one nearest you. walnut cabinet, complete with aU accessories. make the best mechanics to work on your car. Allow him to set up an Ozarka in We have a few Openings You wouldn't think of buying any your home. car, no matter how low its price. He will let you do all the tuning so for the Right Men t; nless you knew you could receive that you can satisfy yourself as to HILE there are today 4364 Ozarka r Wseotatives, some territory is still open service by men who know how. exactly what it will do for distance, want men who believe in the future of volume. tone and ease of tuning. -men who arc tired of working for some one e Treat the purchase of a radio in­ men who would like to add to their present in. stru ment in exactly the same manner His factory training enables him by devoting their evenings to Ozarka. At the start you can keep your prescnt POSt if you wish lasting satisfaction. to keep every Ozarka which he sells, Late r on. after you have proven what you en: Service is just as necessary, just as working just as it did when new. ~:~n E~~':n:ri~1 t~:~ ;~ullrllp~;~~~i~~i~i:c:.use il impor tant on a radio instrument as Any radio. no malter what its price The man we want may not have much m but he is not broke. He has lived in his comml it is on an automobile. may be, will only be as satisfac/ory as for some time-he has a reputation that his we Occasionally little things will go the trained service behind it. ~~~dh~h:a~e~~~ ~!l;:t mo~~~ ~~~!~hri~~~$ r::, make money. He may know nothing about rad ::I:~:d~s~ta~U!~en;:I~tmi~~c~~~:~t hhi~.w~ith_ out cost. The field in radio is wide open for the trained man. The success of the 4.364 Ozarka representatives f:~:esc:ph;tof~hecOz~~kalfP)~~. a:e li86e~e:;~b:!~ which tells a true story of how big money and a permanent business can be built in radio. It is a INCORF'ORATE:D :~~~~ed~ ¥\:i~ to:kh1a~o~~w~e':n!~i; ;~~e h~~e:~ start making extra money immediately and within 120 W. A ustin Avenue B CHICAGO, ILL. a very short time establish a business of their own. RADIO AGE for October, 1926 Th~ Magazine of the Hour

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Address_... __ ..... __

Town .. _._ State... _ ... 2 RADIO AGE for October, 1926 The Magazine of the Hour

Chats With the Editor VERY now and then the truth of The Maga:ine of the Hour E the old slogan "Quality material Established l\tlarch, 1922 is the cheapest in the long run" is forcefuIly brought to' our attention. Volume 5 October, 1926 Number 10 This time by the performance of one of our readers who admits that for years he has been a liberal patron of CONTENTS the dime counters in the well known FOR OCTOBER ISSUE 5 and 10 emporiums where he bought all the constituent parts of a great Cover insert by Gordon K. Martin radio-to-be. Survey of Power Supply Devkes______5 By F. A. Hill For years this gentleman has been See and Hear Wavelength with Crystal Tube______8 writing to this magazine to extricate By S. R. Winters him from some of his dilemmas with the radio sets he has built. In every Nine Tube Super Brings Back Fan's Faith______!) Broadcasting and the U. S. Navy...... ______11 case we have tried to straighten him out and put him on the right track, in By Lieut. Comdr. A. P. H. Tawresey Allen-Bradley Supplies Two Fields ______. ____ .... 13 may instances with good success. By F. A. Hill Our greatest surprise recently, how­ Radio Patrol of Railroad Trackage ______._ ...... _. 15 ever, was a chance visit to his neigh­ What Type Loud Speaker Should I Use? ______17 borhood when we decided to drop in By H. Melchior Bishop on this reader and see just how much Tube Socket as Plug for Receiver Testing______20 radio material he had collected during By Charles E. Felstead his four years apprenticeship in radio. "The Ladies-God Bless 'Em" ______. __ 21 Mr. Reader was quite glad to see us By Dorothy Brister Stafford and immediately took great pains to Converting 9BHX Into Crystal ControL_ ...... ______25 display the latest result of his handi­ By F. A. Hill work, a tuned radio frequency set, in Raytheon Design for ABC Power UniL ______33 a beautiful cabinet; with an excellent By Miles Penny backer power supply device on the floor below Uncle Sam Chats with His Dairymen ______._ .. _____ , 37 the receiver table and an accompany­ By Milton S. Eisenhower ing high grade A battery. Pickups and Hookups By Our Readers ______. 41 But our greatest marvel was the in­ With the Manufacturers ...... ______...... 44 terior of the set. Instead of the ma­ Correct List of Broadcasting StationL54-56-58-60-62 terial from the red front bazaars on Ductile Thorium and Its Uses ____ . ___ .... _._. ______64 which he had previously placed so By F. C. Kelley great reliance, we now beheld an ag­ Classified Advertisements ______._. __ . ______._ 68 gregation of the highest quality mer­ chandise on the market. Every single Radio Age is published monthly by RADIO AGE, Inc. item was absolutely first class and MeIDher: Audit Bureau of Circulations. some of it was quite expensive. In Publication Office, Mount Morris, III. reply to our query he said at last he 404 North Wesley Ave., Address all eommunications to RADIO AGE, Inc. had become wise to the ways of the Executive, Editorial and Advertising Offices world and if a magazine consistently 500 N. Dearborn Street, Chicago, Ill. used only quality material in its hook­ ups there must be some good reason FREDERICK A. SMITH, Editor F. A. HILL, Associate Editor for it. He found he could save money M. B. SMITH, Business Manage? by using the recommended parts of high quality which gave uniformly Advertising Manager good results. HARRY A. ACKERBURG 500 N. Dearborn St., Chica.go. IU. Consequently there is one less eager Eastern Representative fan leaning over the bargain counters HEVEY & DURKEE, 15 West 44th St., New York, N. Y. a nd our reading public again is let in Pacific Coast Representative on the interesting metamorphosis of V. M. DEPUTY & ASSOCIATES, 515 F. W. Braun Bldg., a radio fan. Los Angeles, Cal. Final Advertising forms close on the 20th of the 2nd month preceding date of issue Vol. 5, No. 10. Issued monthly. Subscription price $2.50 a year. September, 1926. Entered as second-class matter at post office at Mount Morris, Illinois, under the Act of March 8, 1879. Copyright, 1926, by RADIO AGE, Inc. Editor of RADIO AGE. RADIO ACEjor October, 1926 The Magazine oj the Hour 3

"They last twz'ce as long as the smaller Batteries of equal voltage"

" THAT'S a pretty broad statement, rou a favor-making your first invest­ laboratories has made in "B" battery Tom. Won't you have to make it ment cost yo u a little less. That little economy, dependability and satisfaction. conditional on the number of tubes in difference looks like a lot to a good Dry liB" batteries give a noiseless the set or the use of the new power many folks w ho are buying their first current, pure D. C. (direct current), tubes?" ;;et: equi~p~d with . tubes, loud spe~ke~; the kind that is essential if you prize "No, sir! Under the same operat­ A and B batterIeS and everythmg. pure tone. ing conditions-\vhether you use four, Heavy-Duty batteries last twice as Send for booklet, "Choosing and five tubes or more, whether you use a long as the smaller batteries of equal Using the Right Radio Batteries," power tube that uses up to 135 volts, voltage. Eveready Heavy-Duty Bat­ which we will be glad to send you teries are the great contribution that the Eveready Heavy-Duty No. 770 or upon request. This booklet also tells the world's foremost electro-chemical the even longer-lived Eveready Layer­ about the proper battery equipment for bilt No. 486 will last twice as long as use with the new power tubes. There's the smaller sized 45-volt batteries." an Eveready dealer nearby. "Well, they ought to, they cost Atanllfactllr~d and guarantud by more." ~':;':Ti,:No.4 8';~6. ~t I~__'. . NATIONAL CARBON CO., INC. "Yes, about a third more-hut last­ RI G BT-E ~eT - ~ , eadll DrJ/ Cell ,.\,tl.IlI,g New York San Francisco ing twice as long, they cost much less." R!ld~o , cA" 1.:'-...... BatterJl.l ~ , ~ Canadian National Carbon Co., Limited, 'IYour arithmetic is good, Tom, but vo ltll. ~ I Toronto, Ontario if that's so, when I bought my 'et why I ,":~ did the dealer equip it with" the smaller Tuesday night means Eveready Hour- Eveready 772's? Why didn't he put 9 P. M., Eastern Standard Time, through in the Eveready Heavy-Duty Bat­ stations: WEAF-New York wSAr-Cincinnati teries ?" mrEREADI wJAR-Providence wTAM-Cleveland ""'EEl-Boston wWJ-Detroit "He probably thought he was doing WTAG-Worcestff wGN-Chicago Radio Batteries WFJ-Philadelphia woc-DaV€nport NOTE; A "e" battery gives a quality of recepti?D .'Fur last longer WGR-BuQalo _1 Minneapolis unobtainable without it and greatly increases the hie WCAE-Plttsburgh wccv), St. Paul of your "B" batteries. WRc_JVashing/un KSD-St. Louis 4 RADIO AGE for October, 1926 The Magazine of the Hour

When You Put ELBCTRAD CERTIFIED JACKS on Your Set, You Can Forget Them T'S a lot of fun experimenting with different I circuits and hookups, but you don't want to waste any time experimenting with jacks. You want jacks that can be depended upon to do their work without your giving them any thought. The new Electrad Certified Single Circuit Jacks, open and closed, are that kind. Solid brass construction. Positive acting spring of phosphor bronze. Sterling silver contact points. Insulation of hard rubber. Tinned soldering lugs, so placed that good connections can easily be made. Re­ quire little space behind panel. Any good radio store has these jacks or can easily get them for you. Guaranteed electrically and mechanically. Prices-open, 2Sc; closed, 35c; in Canada, open, 35c; closed, SOc.

ELBCTR.f\.D CERTIFIED S On When They're On - Off When They're Off ! You don't want any halfway business about a switch. It must be either 100% on or 100% off. When you hear your Electrad Certified Switch click you know. Solid brass construction. Tinned soldering lugs placed to make easy connections. Neatly designed, genuine Bakelite knob. Requires .less than one inch behind panel. Adds to the appearance of your set. Price 40c, in Canada 60e.

For Perfect control of tone and volume use the Electrad SOO,OOO-ohm Compensator. For free hookup write 428 Broadway, New York City RADIO AGEfor October, 1926 The Magazine of the Hour

IFISI lSI lSI 'S, 'S' ,,;;1 "~~E" 'S' lSI 'S, 'S' 'Ill' 1~Ejj] ~ ~ ~ ~

S M. B. Smith A Monthly Publicolion Frederick A. Smith mi' Bu..inellS Manager Devoted to Practical Editor rn Radio m ~1~E=SIllI lilIl lSI lSI lSI 181 1,,01 'BI lSI lSI 'SI 10;;1 u~eJ

i Power Supply Devices are Taking Strong Hold on Public By F. A, HILL ( d s.rociale Edilor)

NLESS one has been fol­ bulky obj ects and costs excessive. provided. This gives us two U lowing the plate supply Condensers of high capacity were types of rectifiers from which a device subject from its in­ not so easy to manufacture and startling number of combinations ception it is rather hard to ap­ keep costs within reason. can be made, and which has preciate the obstacles which have Early in the game there were proved a boon to the makers of been overcome in the production only perhaps one or two interests power supply devices. of a substitute for batteries in devoting any of their research to A recent survey made by the the operation of a receiver. the production of a good elim­ writer in Chicago somewhat sur­ Theoretically plate supply de- inator. As the commercial prised us as to the magnitude of I vices have been possible for a broadcast sets progressed from the local manufacture of power long time but there have been nu­ the two tube variety into the supply devices. merous factors which had to be four, six, eight and ten tube Where Majestic Is Made considered, and which when dis­ class, the drain on B batteries (even with a biasing current on NE of the plants visited was regarded, made eliminators im- O that of Grigsby, Grunow practical. Rectifying devices in the grid) was rather heavy, and on unbiased receivers the drain and Hinds Co., who manufacture the earlier days were none too the well known Majestic current efficient and had limitations in was excessive. This meant that someone had to develop an elim­ supply units, and whose presi­ only being able to handle a rela­ inator that would take care of dent, B. J. Grigsby, gave the tively low voltage. Chokes, as heavier current with greater volt­ writer an idea of the scope of this first constructed, were rather ages, and which would have an particular plant. exceedingly long life; in fact the Manufacturing eli min ators life of the eliminator would be from assembled parts would be an almost indefinite one, being limited only by the life of the rec­ tifying device, which of course is replaceable. While manufacturers were turning their attention to the question of chokes, condensers, transformers, the tube makers were doing research on the rec­ tifying devices of which there are now only two on the market. The first is that made by the Raytheon interests and described elsewhere in this issue. The sec­ ond was the Rectron made by the Above is seen the Majestic Master·B with Radio Corporation. In the a capacity of 60 milliampel es at 150 former no filament is required For sets up to 12. tubes the Majestic volts, suitable for use with Radioias 25, Super-B with a rating of 45 milliamperes 28 and 30 while in the latter a filament is at 150 volts is used b RADIO AGE for October, 1926 The Magazine of the Hour is then placed in its metal con­ tainer and sealed, to become one of the integral parts of the elim­ inator, and one on which a great deal depends.

Condensers Need Tests ONDENSERS which are to C remain in an eliminator for a long time and which must op­ erate under varying service con- . ditions, must be thoroughly tested beforehand to make sure 1'>- they will stand up under the vol t­ age s impressed. Accordingly Schematic circuit of the Bremer-Tully B power unit which takes care of dif­ they are tested two or three times ference in line voltages by means of the plug in system shown at the left of the diagram during course of manufacture, and when finally assembled are given a final test to see if they will break down. Since the sup­ satisfactory if all the parts could insulating medium, thoroughly ply units must contend with high be selected with that object in impregnates the condenser. A voltages, it is imperative that the view, but such a condition seldom baking process is used first to dry condenser bank have an ample obtains. Grigsby, Grunow and out any possible moisture, after safety factor over and above the Hinds, formerly in the manufac­ which the Halowax is allowed to normal voltage rating of the unit ture of automotive accessories, to take care of stray potentials immediately saw the necessity of of a higher order than usually making every component article encountered. themselves and accordingly set During the season there are about it. They made up their twelve hundred workers assem­ own transformers, which are bling these products. Twenty­ completely shielded in a single five hundred supply units per day unit. Then they made their con­ is the capacity of the plant and denser block, which is likewise when we are informed that the shielded. The chokes they also Grigsby, Grunow and Hinds in­ made and placed in another terests absorb more than half of shielded container. The resist­ the Raytheon tube factory ou t­ ances and the tubes are the only put, it is not difficult to see that articles which they do not make. this industry is of more than By construction of the trans­ Here is the American electric plate supply passing importance. former, choke and condenser set which also uses the Raytheon tube now Here, as in other large estab­ bank in individual units, the as­ grown so popular both with manufacturers lishments, rigid inspection is sembly of the finished product and broadcast listeners necessary to insure elimination of is expedited. It also provides fill in air spaces in the condenser. returns. Even the Raytheon for complete shielding of all When finished and dried the unit tube is again tested up to its parts. Likewise it means that if is rigid and hard as a brick. It manufacturer's rating of 60 mills a defect develops in anyone of the units, the offending unit alone has to be removed, leaving the balance of the assembly unaf­ fected. Quantity production methods similar to those used in all large manufacturing establish­ ments are in use in the produc­ tion of current supply units. In the construction of the con­ densers the paper and foil are fed, rolled, and completed by me­ chanical process so high speed work is possible. These con­ Schematic circuit of the conventional Raytheon eliminator circuit with re­ sistance values as suggested by the Allen-Bradley Co. Resistances R2 are densers are, when ready for in­ No. 10 Bradleyohm; R3 is a No.5 Bradleyohm, while Rl is a 10,000 ohm sulation, placed in pressure vats Bradleyunit where the Halowax used as an RADIO AGE for October, 1926 The Magazine of the Hour and is repacked in another con­ hookup with resistance values have been expended on the prob­ tainer and sealed by the makers which Allen Bradley consider lem. A elimination is quite pos­ of the Majestic so when it best for general operating condi­ sible if several contingencies are reaches the public it will be o. k. tions. The fixed resistance, R1, met; the first the filtering, or III every respect. Variable re­ is a Bradleyunit, 10,000 ohms. smoothing out of the supply at a sistances for the voltage control The two variable resistances, R2, heavy current draw, and the sec­ are made by Allen-Bradley Co., the first handling the detector, ond the rectifying device which and this feature enables one not and the second the positive 45 must handle considerable cur­ only to take care of the different volt tap, are known as the Brad­ rent. What form of A eliminator voltages required on a receiver, leyohm No. 10, while the variable will ensue is difficult to forecast, but to compensate for differences resistance shown to the right of although it is well known in the in line voltages. the R2, is known as the Bradley­ industry that many an organiza­ ohm No.5 and controls the 90 to tion is working feverishly to be Bremer-Tully Unit 120 volt tap. The high position the first to come on the market A NOTHER form of voltage of course has no resistance and with a perfect A eliminator. ft compensation is the method represents the full output volt­ One type of A eliminator has used by Bremer-Tully Mfg. Co., age of the unit. been built on the thermo-couple and shown schematically in the Included in this article is a principle, but so far as we know diagram on page 6. In this case view of the American Electric this type has not been devel­ the resistors at the output end plate supply unit, shown on page oped to a conclusion. of the supply device are fixed, and 6 and which also uses the Ray­ Another method tried is mak­ variation is made by plugging in theon tube. In our September ing use either of the half wave the plug on a tapped primary Tungar charger, or an arrange­ which is in the 110 volt line. ment for double wave Tungar This scheme was adopted by rectification, the output being Bremer-Tully when they decided smoothed down by chokes and to manufacture an eliminator for condensers. It is this method use with their own receiver which seems to lend promise, which they could recommend viewed from the fan's stand­ without reservation. This was point, since a great number of due, probably, to the fact the lay enthusiasts already have the public has an idea that any elim­ bulb type of A battery charger, inator will do for any receiver, and would have only to secure whereas there· is no subject on the filter and the chokes to com­ which a fan can get into more plete the layout. However in trouble than trying to make cer­ this case the filter and the tain types of rectifiers that will chokes are the devices on which handle a two or three tube set, further research work must be work efficiently on an eight or done in order to get them down ten tube receiver. Hence to ob­ to a practical and inexpensive viate this difficulty on the part basis. When this objective is of the public the B-T organiza­ attained the radio public will tion made their own plate supply then be in a position to fully device and know exactly what it realize the benefits of simplified will do with their own receivers. Bremer Tully's B power unit made for radio. Aside from the fixed resist­ use particularly with their own receivers, All of the foregoing applies ances which are included in the but can also be used with other standard sets only to the metropolitan areas Bremer-Tully B power unit, where city lighting current is there is also included a separate blueprint section we showed the a vailable. In the remoter dis­ set of .resistances to give differ­ Thordarson-Rectron combination ent values of voltage than those for plate supply and power tube tricts where power is not avail­ shown in the unit on this page, operation, while in another por­ able the batteries remain and will namely; positive 22 V2, positive tion of the magazine the Silver remain supreme for a number of 45, positive 90 and positive 135 plug-in B supply unit was de­ years. All battery manufactur­ volts. Thus the plug-in arrange­ scribed. Reference back to these ers are seeing the necessity of de­ ment gives some control over the two articles will help in gaining veloping the rural markets to a line voltage while the extra set an idea of the power supply ques­ greater extent than before. And of resistances gives still further tion. sirrce the rural market is prob­ flexibility to the unit. These re­ ably many times larger than the sistances are merely slipped into "A" Elimination Next clips which are shown on a dia­ A S to the future. Elimination city market, it would seem that gram attached to the supply ft of the A battery is next on battery makers of both the dry unit. the list, but it will not be accom­ and wet cells, will have a good Schematically on page 6 is also plished until a great deal of en­ volume of business for years to shown the conventional Raytheon gineering work and research will come. RADIO AGEjor October, 1926 The kfagazine oj the Hour See and Hear Wavelength With Quartz Crystal Tube Visual Indication of Resonance is Now Develope:d By S. R. WINTERS

UARTZ crystal not only vices may be provided at one or brates mechanically at a rate of Qpossesses the magical prop­ more controlling points, which "ery high frequency. The two erty of acting as a gover­ may be at any desired distance German scientists found, upo,. nor in precisely controlling the from the transmitter. The aux­ further investigation, that the frequency or wavelength of a iliary apparatus for this purpose stationary electrical oscillations radio transmitting ' station but, of quartz crystal, which action by virtue of a newly discovered takes place in case of reso­ quality, it demonstrates the al­ nance, .may be visible. This most uncanny power of lighting luminous effect is accomplished a lamp. Thus, the magic min­ by hooking up the condenser eral becomes the magic Alad­ plates and the quartz rod with a din lamp, too! glass vessel, which must be The phenomenon of a piece evacuated to a pressure of 10 of quartz crystal producing a to 15 millimeters of mercury. visible light in a lamp contain­ Lead-in wires, sealed airtight ing a gas mixture of helium and into this vaCuum lamp, serve the neon was discovered by two Q. purpose of connecting the con­ German scientists-Professor E. denser plates to the oscillating Giebe and Dr. A. Schiebe of ~;r;~ circuit. Berlin. "Light-resonators as . ;- "The alternating electrical frequency standards for the field of such an oscillating cir­ measurement of wavelengths," , cuit," indicate these German in­ descriptive terms designating .. ventors in explaining the phe­ new devices designed as a result -- nomenon, "will cause by reason of discovering this phenomenon, of the electrical polarization of were recently demonstrated at the quartz-rod alternating de­ the Radio Laboratory of the Bu­ formations of the latter, which reau of Standards by David L. in the case of resonance will Loewe of Berlin. have the effect of generating If these light-resonators are stationary elastical oscillations. universally adopted by the ap­ The deformations due to these proximately 19,000 radio sta­ oscillations will gi ve rise to sec­ tions in the United States, it will ondary alternating voltages mean that the operators are en­ upon the quartz-rod, which abled to both see and hear bring the rarified gas contained whether or not their transmit­ in the glass-vessel to lumines­ ters are functioning precisely on cence. The resonance is ex­ the assigned wavelengths. Of consists only of an amplifier tremely sharp and, therefore, this new German invention, we and as many loud speakers as the luminous effect is adjustable are told that the resonance ef­ there are controlling points." down to one-half per mille of fect is not only made visible but the wavelength. By properly may be rendered audible by use Frequency Standard choosing the condenser plate of a loud speaker. This implies HE light-resonator as a fre­ and the degree of vacuum the remote-controlled transmitters in T q uency standard is a direct­ result may be attained that the scientific as well as the ly indicating-measuring instru­ the discharge will take place popular sense of the word. "For ment. As originally discovered throughout the dis c hal' g e instance," suggests Professor by Prof. W. G. Cady of Wes­ space." Giebe, "the luminous effect for leyan University, a quartz rod The light resonator, accord­ adjusting the wavelength may when properly placed between ing to claims, is absolutely ac­ be employed in the transmitting two condenser plates of an elec­ curate, so long as the quartz rod room itself, while acoustical de- trically oscillating circuit vi- (Please 110"It to page 46) RADIO AGE f or October, 1926 T he 1l1agazille of the Ho ur 9 Building 9 Tube Super Brings Back Faith in this Receiver Absence of OsciLLation and Sim­ pLicity of Construction are Features O MUCH has been written glance will readily show the the government to broadcasting S on superheterodynes at simplicity of assembly, ever y­ stations. times it seems the subject t hing being on a line. The base­ The set consists of th e fi rst de­ has been worn threadbare, yet boar d layout was used instead t ector, four intermediat e stages when we are just at the point of of the subpanel on account of using long wave transformers, exhaustion something generally this type of arrangement being th e second detector, the oscil­ turns up that is interesting. more pleasing to t he set b uild­ lator, and two audio frequency These remarks apply aptly t o er. If th e set looks nice in t his stages. No potentiometer is used the nine tube super which is dress, it will look even better if since flexibility of the interme­ herein described, and whose done up in sub-panel fashion, diate stages is provided th rough· performance is such that it is although a bit more work is in­ filament rheostat controlling all felt readers of this magazine volved in following t hat f orm of of the intermediate tubes. Am­ will find the flame of their in­ construction. perites are used in the rem ain­ terest renewed on the question Taking advantage of th e fact der of the circuit which does of superheterodynes. that transformers designed for away with further filament co n­ Simplicity of control and ease long w ave work will serve nice­ tr ol. A grid modulator serves of assembly are the two features ly for t he interm ediate stages of to alter the volume in the loud which should appeal to the set a super, we secured a set of speaker. Thus there are two builder, while the selectivity of long wa ve transformers de­ major and one minor controls. the receiver itself will appeal t o signed by th e High Frequency The condenser on the left is that both the set builder and the ex­ Laboratories of Chicago and for the loop; the condenser on perimenter in search of good re­ which are peaked for 37.5 kilo­ the right is the oscillator. The sults. cycles, t his value being desir­ r h eostat for the intermediate Pictorially the nine tube able to dodge between the ten stage filaments is shown as vol­ super is shown on this page. A kilocycle separation allowed by ume and is located at the left of

In the upper picture is shown[the baseboard layout of the Radio Age Super 9. Beginning at the left of t he baseboard the tcansformers used are as follows: H210, H210, H215. H210, HilS, F320, L425. F320. The t ransfo rmer sh own betw een t h e t wo Remler condensers ~s an L430 RF transformer. Thergrid of the sixth and seventh transformer is n ot ;hridged directly t o the tube socket. See the schematic' for the actual electrical connections 10 RADIO AGE for October, 1926 The Magazine of the Hour the panel. The loop terminals Duro-Metal, is used with the re- Operation Simple come in at the rear of the base­ ceiver, provision being made at OPERATION of the nine­ board at the right, while the the left rear of the baseboard tuber was quite simple. As­ J ones base mouting is located at for the three loop connections. suming that all connections the right rear corner of the A total of 135 volts of B battery, have, been made in accordance baseboard, where also are found (three 45 volt blocks in series) with the schematic, turn battery connections for the loud speaker will suffice for operation. A switch on; set the midget con­ and the C battery. good B eliminator may also be denser half way in; turn the Schematically the circuit is used if desired. The Jones 7 (Please tum to page 46) shown on page 10. This ar­ wire cable should be connected ;--______rangement is for nine 201-A as follows: Red-A; Green-A; tubes. It can readily be con­ Black-B; Brown 22%; Pink verted for use with 199's by sim­ 67%; Yellow 112% and Blue ply altering the Amperite resis­ 135 volts. It will be noted the tances. Examination of the schematic will show that two in­ I-- -~- termediate stages are followed LIST OF PARTS by a filter, then another inter­ I 1-7x30 panel, 3-16 mediate followed by another fil­ 3-HFL H210 transformer~ ter. This procedure results in 2-HFL H215 transformers I-HFL L425 choke unit maximum selectivity. Further 2-HFL F320 audio transform­ selectivity may be secured by al­ ers tering the capacity of the I-HFL L430 R. F. transformer 2-Remler .0005 mfd variable midget condenser in the loop condensers circuit. 2-Marco dials for above con- densers No Body Capacity l-Chelten midget condenser N ACCOUNT of using the 5-Yaxley I mp jacks O I-Jon.s bas. mounting and '7 Remler condensers there is . wire cable plug complete absence of body ca­ l-Yaxley 6 ohm rheostat l-Yaxley filament switch pacity both on the oscillator and 3-Amperite resistances I-I-Ai loop circuits. These condensers 2-112 and mountings are of the twin rotor type and 9-Benjamin cushion sockets I-Electrad I mfd bypass con~ the'shaft extending through the denser panel (to which are affixed the 2-Muter condensers .0005 mfd Marco dials) does not become a I-Duro Metal Qualitone collap~ sible loop part of the circuit since the I-Duro Metal Qualitone loud shaft carries a bakelite gear speaker which engages the rotor plate I I-CentraLab 0~200.000 ohm gears. In previous types of I_ _~~~hm ___. supers this form of condenser has been found highly satisfac­ oscillator is supplied with only tory where the oscillator ca­ 22% volts which is very desir­ pacity. span is from grid to able in order to cut down the plate. If the oscillator circuit is possibility of the oscillator pro­ changed to the grid-filament ca­ ducing a variety of harmonics. pacity span body capacity can These harmonics are naturally be eliminated, although the loop produced at any voltage, but might still have a trace. they are weakest at 22% volts, Grid condensers and leaks whereas with double and ,triple are not used but instead detec­ that voltage these harmonics tion is accomplished by C bias would be more than bother­ of the detector grid. The bias some. The range of the oscil­ value for all 201-A tubes was lator coil with the Remler con­ found to be 6 volts, thus simpli­ denser referred to will be from fying the C battery voltage approximately 190 to 595 me­ problem. Using the voltages ters, which should serve to take specified in this article and with in all of the present broadcast the proper C battery value, the channels. To go further down total milliampere current used in the wavelength scale another runs from 10 to 16 mills, which oscillator could be used which is exceedingly low considering would throw the set into the the number of tubes and the re­ short waves-but that is anoth­ sults secured. er subject on which we may A center tap loop, such as the have more to say later. RADIO AGE for October, 1926 The Magazine of the Hour 11 Broad­ casting and the U'.S.Navy By Lieut. Comdr. Alfred P. H. T a wresey

o many people the ad­ T vent of broadcasting about five years ago marks the U. S. Navy battleship showing various radio antennas, each for a separate transmitter beginning of radio history. They know vaguely that radio teleg­ gove1'nment is charged with the broadcasting, the newest form of raphy was used prior to that regulation of radio communica­ public service to enter the radio time for sending distress mes­ tion as a means for J'endering a field, entered a field already con­ sages from ships, but relatively public service. The goveJ'nment gested. It has been provided for few know the large part played uses J'adio communication in the by rMdjusting the frequency by radio in the conduct of the administration of its business." channels, and even the types cf world's business, even prior to equipment, used by the older the World War. National Defense services. These readj ustments The United States Government ATIONAL defense is simi­ have been difficult and costly and as a whole became interested in N lar in some respects to a in many cases have entailed seri­ radio in 1904. At that time none conflagration and the forces of ous derangement of established but government departments national defense to a fire depart­ service. could risk the outlay necessary to ment. In training for the pur­ The band of frequencies relin­ develop and maintain what was pose for which they exist both quished to the exclusive use of then an untried and uncertain fire departments and national de­ broadcasting is the one band means of communication. The fense forces require constant ex­ which can be covered efficiently first administrative policy in re­ ercise with their special equip­ by a simply constructed receiver. gard to radio was drawn up in ment, for' which they must enjoy Frequencies below it (wave­ 1904, and was approved by Presi­ special privileges on the common lengths above it) require more dent Roosevelt. highways. When quelling a fire expensive apparatus of greater Advances in the art and or subduing an enemy they must weight and occupying more space. changed conditions, inc! uding enjoy undisputed sway over such Frequencies above it are difficult broadcasting, aircraft communi­ portion of the common way as to handle and are uncertain and cation, radio beacon, and the ra­ they need. erratic. dio direction finder, made it im­ The ordinary citizen demands Ships, aircraft, and extremely perative to revise the administra­ of radio merely that he be able to isolated points on shore should tive policy with regard to the use send a message from jlA" to HE" have preference in the use of of radio by the government. In and receive a reply in a; reason­ radio facilities over communities 1925 a committee of representa­ able time, or the ability to listen already well supplied with cables, tives of all the government de­ simultaneously with countless wires, telephones, newspapers partments and several independ­ others to broadcast program. and other means of communica­ ent government agencies drew up Naval communication requires in tion. Such radio communication a tentative statement of govern­ addition to these ordinary de­ as forms the sole dependence for ment domestic radio policy. One mands, rapid, reliable, accurate the safety of human life, or the important feature of this state­ and often secret communication sale means of conducting the ment, carried forward in prin­ between large numbers of corre­ world's essential business should ciple from the earlier draft of spondents in restricted areas, si­ have rights superior to that 1904, is as follows: multaneously with that at ex­ which exiS'l:s solely for entertain­ "The government's intel'est in treme distances and against de­ ment, individual profit, or other radio communication is para­ liberate enemy interference. private purpose which could be mount for national defense. The Some do not appreciate that achieved by other means. 12 RADIO AGE for October, 1926 The Magazine oj the Hour The Fourth National Radio transmitters for simultaneol,ls a form of disturbance known as Conference marked an attempt to communication on different cir­ "mush" which is apparently with­ reach a needed degree of stabili­ cuits, and practically all the out frequency adjustments, and zation in radio matters, par­ shore stations used two or more which effectively blankets recep­ ticularly in the general assign­ transmitters to effect simultane­ tion on all frequencies. ment of frequency bands to vari­ ous communication with two or The properties of the vacuum ous services. Radical changes in more ships or other stations. tube were known to the navy, but frequency assignments by pre­ Practically all this apparatus the tube had not yet proved its vious conferences, not only pre­ was designed to operate only in reliability for naval use. Tubes vented rapid compliance with the were not available in quantity, reC(lmmendations of the confer­ nor was their average life in ences, but also tended to engender service sufficient to warrant their a lack of confidence in the ability adoption. Suitable vacuum tubes of the radio industry to regulate were not then made by American itself by mutual agreement. manufacturers, and while foreign Each general branch of the procurement would have been radio industry should be able to possible it would have been un­ know reasonably in advance what patriotic and militarily unsound. general frequency bands it may Since the beginning of broad­ expect to use for the conduct of casting, the navy has replaced its business, within which it may spark transmitters for regular be expected to reap the benefits service in 27 shore radio stations. of advances in the art and to set­ Twenty-four shore radio stations, tle its own problems. This im­ formerly using spark transmit­ plies neither rigidity nor stagna­ ters have be~n closed permanent­ tion. New services, or improved ly, and the final closing of two services can be provided for by more is projected for the near fu­ suppression in whole or in part ture. Plans for the current year of older and less effective ones. include the replacement of 14 ~~o, navy owns and operates more spark transmitters with one of the largest radio systems vacuum tube transmitters for under single control in the world. regular service. Many things have been under­ taken for the express purpose of Exit the Spark Set aiding broadcasting. Owing to the extent of the navy's radio OMPLETION of this pro­ system, which was full grown be­ C gram will leave but 43 spark fore the advent of broadcasting, transmitters in regular service in and to the necessity for long and the entire shore system of the costly development of non-inter­ The Navy's only broadcast transmitter, navy. Of these, 4 are in Alaska, fering equipment, modernization NAA. located at Arlington, Va. and 12 are outside the continental of the navy's apparatus has not United States, leaving but 27 in been rapid. Much unjustified the band of frequencies (wave­ regular service on shore in the criticism has been leveled at the lengths) later reserved for the United States. Of these 27, 21 navy on this account, regardless exclusive use of broadcasting. are low-powered transmitters re­ of the facts that research and de­ The principal dependence was the stricted solely to use on the radio velopment consume time; that cheap, simple, rugged and reli­ direction finder frequency which the forces of national defense able spark apparatus. Unfor­ is well removed from the broad­ cannot adopt new and untried tunately this type of apparatus casting band. causes disturbance over a wide equipment without exhaustive Four arc transmitters on shore tests as to its efficacy and reliabil­ band of frequencies on either side of the one to which it is adj usted. have been replaced with vacuum ity; and that the provision of tube transmitters, and 4 other public funds for simultaneous re­ There were a few arc trans­ arcs have been fitted with special habilitation of all the navy's mitters ashore and afloat. The devices to reduce their disturb­ equipment is not economically arc transmitter is rugged and re­ ing emissions. Experimental high justifiable. liable and can be adjusted so as powered tubes are being devel­ to occupy a much narrower band World-Wide System oped to replace the high powered of frequencies than the spark. arcs. The first of these experi­ WHEN broadcasting started Unfortunately, however, the arc mental tubes is already in service the navy was operating emits energy in a series of har­ and the other is expected to be­ about 150 radiotelegraph stations monic frequencies. Objectionable gin operation in a few days. on shore, in a world-wide system, and interfering energy has been and radiotelegraph stations in measured in arc harmonics as In places where it has been im­ about 500 vessels at sea. Many high as the thirtieth. Also, arcs possible to replace interfering of the vessels used two or more create in their immediate vicinity (Pl e a~ e turn to page 50) RADIO AGEfor Oclcber, 1926 The Magazine of 'he Hour 13 Allen-Bradley Co. Supplies Electrical and Radio Field By F. A. HILL (Associate Editor)

ESISTANCES w he the r R fixed or variable have long been, and will for many years be a vital and essential part of radio transmission and recep­ tion. Resistances had their first inning with the birth of the elec­ trical industry; their second in­ ning came with the appearance of broadcasting. Other fields will later be developed just as nearly everything today is adapt­ able to more than one use. In the manufacture of resist­ ances some of the larger organi­ Here is shown the Brad­ leystat assembly line with zations which had been making a capacity of 5000 per 8 resistances for the electrical field hour day. Five testing stations are provided to saw a new outlet for their prod­ insure electrical perfection uct and entered the new field with a product on which they al­ ready had years of experience. Th us they not only served their to enter the radio business when world. When the public demand original industry, the electrical, it first blossomed. That com- for radio sets assumed such pro­ but also took in new territory in pany has been making resistance portions the Allen-Bradley or­ the broadcast game. and other controller equipment ganization, having noted the Allen-Bradley Company, at for years and had built up an en- trend, launched into the new busi­ Milwaukee, were admirably suited viable reputation in the electrical ness with a line of variable re- sistors, later adding fixed re­ sistors, condensers and other small parts. Today it occupies one of the upper places in the realm of radio with a name that is as well known and favorably received by the public as any of the large manufacturers. More Current Capacity ATTERY elimination, it is B believed spurred the Allen· Bradley Co., on to even greater effort in the making of fixed and variable resistances, for in the be­ ginning much of the poor success of the eliminators was traceable to the fact that resistances then supplied did not stand up under service conditions. Hence there Allen-Bradley's chemical laboratory where much of their research work was a crying need for a good is done variable resistor that would carry enough current to supply 14 RADIO AGE for October, 1926 T he M agazine of th e Hour receivers using up to the capacity veloped a number of interesting and tie automatically in pack­ of the rectifying devices, general­ features in connection with the ages ready for the electric fur­ ly either the Raytheon or the Rec­ manufacture of graphite resist­ nace. The capacity of each ma­ tron. ances. This substance was found chine is 45,000 discs per 8 hour While the regular line of Brad­ years ago to be an excellent re­ day and there are a large num­ leyohms were doing well on work sistance material and the Allen­ ber of them necessary to make up for which they were designed, it Bradley interests adopted it as the rated output of the factory. became necessary to design a new their standard for resistance Rigid inspection tests are ap­ resistor for greater current car­ material. It was and is used in plied to all apparatus to insure rying capacity. In order to do this the makeup of their industrial its meeting requirements both as the resistor housing was made controller equipment, such as to accuracy of resistance and in­ larger, the graphite dis c s motor starters, overload relays sulation factor. This results in doubled in number although re­ and other current controlling de­ diminishing to almost a neglig­ duced in thickness, and greater vices known more intimately in ible quantity the return of mate­ safeguards added in the way of the electrical field. rial due to poor assembly. insulating factors, such as from Some views of the various de­ the frame to the active ele­ Carbon to Graphite partments are shown in the pic­ ments. On account of an elimin­ ISCS making up these resist­ tures illustrating this story, the ator being a power device it D ance units are originally in one of the chemical laboratory was necessary that better in­ carbon form. They are heated being interesting because not sul ation be provided an d that in an electrical furnace to 5500 many readers know that chemis­ new standards of inspection be degrees, Fahrenheit, and after 72 try is playing a greater part in set up. This was done after a hours ensue as graphite. The radio than it was ever thought little r esearch work on the prob­ electrical furnace which the capable of doing. In fact the im­ lem, and today we have in r a dio writer observed had a capacity of pression received after visiting the Bradleyohm type E which 60,000 of their largest controller the Allen-Bradley organization is w as made especially for elimin­ discs to 2,500,000 of the size used that highly trained, specialized ator work. in the Bradleystats. men are more in demand than An inspection of the Allen­ A battery of disc making ma­ ever and this company makes Bradley factory at Milwaukee r e­ chines take the powdered carbon, good use of all the data that cently made by the wr iter de- form it into discs, then stack it science and research affords.

In this view are shown drill and punch presses in operation, the punch press de­ partment in the background RADIO AGE for October, 1926 The l1 f agazine of the Hour 15 Radio to Patrol 11,000 Miles of Railroad Trackage Chicago, llJ1iLwaukee and St. PauL to In.ftatt Short Wa(Je

ECENT announcement by operator who got out the first ap­ American radio amateur s and ap­ R the Chicago, Milwaukee & peal for help. It was another ply it to a great transportation St. Paul Railway that it amateur who received the mes­ system. was about to install radio com­ sage and startled the world with At Strategic Points munication over its 11,000 miles his report. T strategic points on its 2,200 of trackage has aroused nation­ A mile main line from Chi­ wide interest in the project. cago to Seattle it will establish The press of the country, com­ stations f or transmitting and re­ menting upon the idea, in many celvmg code on short wave instances goes so far as to proph­ lengths of 20, 40 and 80 meters. esy that it may mark a new era Thus will be put into operation in the nation's transportation for the fi rst time in history a history. complete radio communications This important new adjunct to service on a railroad. It will be the ordinary telegraph systems linked at all times with the great used by railroads will mean an net of amateur stations, so that uninterrupted communication at its operations will be doubly all times. Only operating of­ checked, and, as far as human in­ cials of a railroad can fully real­ genuity can make it, practically ize what this will mean. Tor­ infallible. nadoes, floods, landslides, wash­ Like many other discoveries outs and other disasters which that have proved revolutionary prostrate land communication in their effects, the new mode of will not affect the radio. railway communication is com­ During the past two or three paratively simple when reduced years, newspapers throughout to its essentials. It is now pos­ the country have recorded a num­ sible for the first time to describe ber of instances where storms Lieut. F. H . Schnell. who has pioneered in detail the t ransmitting and re­ in short wav e work, as he appeared on have isolated a whole community his recent naval cruise to the Antipodes ceiving sets to be installed by the or section. Then somewhere in in the interest of naval-am ateur long dis- Chicago, Milwaukee & St. Paul that vicinity cut off from all com­ tance work Railway. They were planned munication an amateur radio op- On another occasion a great and designed by F . H. Schnell, erator would get busy with his mine explosion occurred in an former traffic manager of the little transmitting set. Soon the area that for hours had been cut American Radio Relay League mysterious ether waves weFe car- off from communication with the and who last year, while with the rying a series of staccato dots outside by a blizzard. Again, it Pacific Fleet, conducted r emark­ and dashes that always began the was one of these legionnaires of able demonstrations on the prac­ message with the most electrify- the air who got out the message ticability of short wave radio off ing word in the language-Help! calling for doctors and nurses to Samoa and Hawaii. The success Startled by this sudden dra- be rushed to the scene of the dis­ of these experiments led officials matic appeal shooting out of the aster. of the Chicago, Milwaukee and air, other amateurs, perhaps hun- The general public little real­ St. Paul Railway t o take up with dreds of miles away, would ner- izes that perhaps tonight the Schnell the feasibility of apply­ vously start recording the mes- silent starlit ether may be carry­ ing short wave radio to railroad sage. ing a message from some lone communications. At their re­ Last year, when the greatest amateur that tomorrow wilt quest he devoted lengthy study tornado ever recorded wiped out startle millions. to the pr oblem, and finally nearly a thousand lives and left a ' The Chicago, Milwaukee & St. evolved the sets described below path of unparalleled destruction Paul Railway is the first to take as the best adapted for the rail­ across Missouri, Illinois and In- advantage of the science largely road's radio communication serv­ diana, it was an amateur radio developed by this l\rmy of 20,000 ice. 16 RADIO AGE for Octoher, 1926 The Magazine of the Hour Schnell believes that higher In making up the spiral induc­ Specifications frequencies are more reliable tances, oak or some other hard­ Ant. Antenna 33' long for 40 than the lower frequencies for wood strips about one-half inch meter band. Antenna 66' long communication over the distances square will be used in supporting for 80 meter band. required by the railroad. In this a brass or copper ribbon. Cpse. Counterpoise 31' long connection it may be mentioned The radio frequency chokes 1 for 40 meter band. Counterpoise that amateur radio station 9EK and 2 are designed for % wave­ 62' long for 80 meter band. at Madison, Wis., and 4 OM at length operation for 40 meters, Bokeelia, Fla., maintained sched­ but will serve also for 80 meter L-l. Spiral inductance (an­ uled operation on 20 meters operation. The radio frequency tenna coupling) 6 turns %" (15,000 kilocycles) and communi­ chokes 3 and 4 are for use in the brass or copper ribbon about cated with each other twice every grid leads of the tubes and while 1/32 " thick, spaced %", inside day from December, 1925, to not absolutely necessary, they diameter 3". May, 1926. may help stabilize the input to L-2. Same as antenna induct­ Use Fifty WaUs the tubes. ance except 10 turns for 40 meter T is believed that frequencies In designing sets to be used by band. Same as antenna induct­ I of 7500 kilocycles (40M) and the railroad Schnell suggested an ance except 18 turns for 80 meter 3750 kilocycles (80M) with power antenna consisting of six wires band. of about 50 watts to be satisfac­ built up in the form of a cage of L-l and L-2 mounted in oak tory to provide communication about 4 to 6 inches in diameter, strips lf2"xlf2", slotted to take the between pivotal stations of the using No. 12 enameled copper ribbon. St. Paul's radio communications wire with the supporting pieces A. Jewell Pattern 64 flush service. It is based on experi­ of substantial hardwood. mounting 0-5 (R. F.) ammeter. ences of stations 9EK and 4DM A piece of solid rod or tubing and many amateurs. The trans­ C-l. National type 450 vari­ substantially guyed will be used mitter is an amateur type. The able transmitting con den s e r accompanying drawing shows the to prevent swaying or swinging (.000450 mfd.). schematic circuit diagram of the in the wind. Complete specifica­ C-2.' National type 150 vari­ transmitter, using two 50-watt tions for transmitting and receiv­ a b I e transmitting condenser tubes, one on each half of the ing sets' to be installed by the Chi­ (.000150 mfd.). cycle supplied with 60 cycle cur­ cago, Milwaukee & St. Paul C-3 C-4. Faradon model UC­ rent. Railway are as follows: (Please turn to page 36)

"'Fe.! TP.

//0 V. ------"""'--- 6'iYCLCS

R.r:c. R

r::------'----'I/;"N\M/\fv--r--W-·,A.

Schematic circuit of full wave self rectified 50 watt transmitters to be used. IIOY. 60CYCLES RADI O AGEjor October, 1926 The Magazine oj tlz e Hour 17 What Type oj'Loud Speaker Should I Use? HE question above is one By H . Melchior Bishop individuals who are to use the T which puzzles many broad· receiving set and reprodl1 cer in cast fans and, in addition, question must be served! is one to which it is hard to se­ dealing with them, at least a su­ cure a safe, sane and impartial perficial knowledge of which type Different T ypes answer. This is due chiefly to of speaker is most suitable for N order to t ry to ascerta in the undeniable fact that each and the set which you are going to I what particular combination every salesman, unless he is a buy, or which you have already of receiver and loud speaker is real radio expert, has his own bought and ar e using with more most apt to please you, let us con­ favorite type, and even make, of or less indifferent results. sider for a f ew moments the vari­ speaker, which he recommends The second, and by far the ation in the characteristics of the indiscriminately for use with any more important step, is to verify, different types of loud speakers set, regardless of make, model, pTe/erably in your own home, on the mar ket. age, or inherent tone quality. the wisdom of your choice or There are t wo general types of A little common sense and choices by actually hearing the speakers on the market, that is, thought will show to anyone (re­ resulting speech and musical the horn type and the cone type. gardless of his or her technical quality produced by its or their These types may be subdi vided knowledge, or lack of it, with r e­ actual operation. I say choices, into a number of more special­ gard to radio and acoustics) that for the course of greatest wisdom ized forms. This is done in the this indiscriminate and slipshod is to make not one, but rather accompanying table, Figure No. method of recommending loud several selections, and then let 1, which gives a method of quick speakers is absolutely and thor­ your own ears tell you which is r efer ence to the different forms oughly wrong, and is bound to best. of reproducer as tliey are men­ result in many misfits due to the The latter course is necessary tioned in the following discus­ fact that both receiving sets and due to the proven fact that a sion, in which they will be r e­ speakers differ widely in their quality of tone which is perfectly ferred to, for the sake of clear­ general characteristics. T his euphonious to one person may ness and brevity, by the numbers leads to the condemnation, very grate harshly upon the hearing appearing in the table. often, of both receivers and re­ of another, and vice versa; not The difference between conical producers which are not in any due to a lack of musical percep­ and exponential horns is shown sense at fault within themselves, tion in eit her case, but merely to in F igure No.2, which repre­ but whose characteristics ar e un­ a f undamental difference in the sents the approximate cross sec­ deniably entirely unsuited for use peculiar sensibilities of the per­ tion of t hese two types. The in conjunction with each other . son hearing that part icular tone. conical horn often has a n en­ The same speaker used with an­ The individual, or the group of larged bell , which does not, how- other type or make of set, or the same receiver connected to an- ;------, other more suitable loud speaker would probably be capable of emitting a quality and volume of sound superbly true in tone and spee

I Figure No.1 CLASSIFICA T ION of LOUD SPEAKER TYPES

HORN SPEAKE RS CONE SPEAKERS

Cone Made of No· 1 Shap e of H orn Horn Made of D iaphragm No. Type of Cone Made of - ' ---- I H Conical or E xpon ential Papier machc or Fibre Metal or M ica I I C R igid Edge, Single or Heavy-Cold Pressed-Medi- Double Cone urn Hard-Long Fibre I Paper. -- Heavy-Cold Pressed - Hard 2H Conical Thin Metal M etal or M ica 2C Free Edge, Single or Long Fibre Paper or Double Cone Parchmentized Paper. -- - Rigid Edge, Single or Parchmentized Paper or 3H E xponen tial !T h in M etal IM etal or M ica 3 C Double Pleated Disc. Varnished Fabric or Gen- -- (Lumiere Type) uine Parchment. 4H E xp on ential H eavy Metal or Heavy M etal and Wood or I H a r d Rubber Of' M etal or M ica Special Horn Fibf' e or B akelite

5H Conical Throat, E x- W ood with Drawn Metal or M ica ponen tial B ody and B rass Throat I B ell. RADIO AGE for October, 1926 The Magazil1 e of llze Hour 19

FIGURE :It...,.

B c o

BG

Oriv/'1f1 Und.s "'1'7- -Sh"..-n.

general ways. Sometimes the made of hard, stiff, parchment­ Consider An Example edge of the cone is flexibly sup­ ized paper to obtain the proper y referring to the above dis­ ported by circumferential rub­ rigidity; consequently its tone is B cussion of the tonal qual­ ber or kid leather strips; some­ full, brilliant, clear, and free ities of the differ ent types of loud times it is loosely held by soft from any tendency to prod uce speakers in common use, and to felt packing around the periph­ "barrelly," muffled tones. their classification in the table, ery; and in one or two makes, it The Lumiere type of repro­ Figure No. 1, accompanying this is absolutely free, all support of ducer, designated as No. 3C, is paper, an approximate selection the cone being accomplished by quite similar in tonal character­ of the proper speaker may be the driving pin, which is made istics to the free edge cones made. To illustrate the method proportionately stronger to bear (Type No. 2C) except that it is followed, let us consider one or the additional strain imposed possibly even more brilliant and two typical examples. upon it. sparkling in musical quality, due Suppose, for the sake of argu­ The results obtained are prac­ to the fact that its rigid, pleated, ment, that the type of set in tically identical in all three types. parchmentized paper disc or which you are interested is ten­ The sound is produced in this discs are held firmly clamped at tatively conn~cted to a speaker type of cone speaker by the their edges. It does, however, of No. 4H type. The set is tuned movement of the cone rather pro d u c e considerable paper to a broadcasting station over than by its flexure, consequently crackle, which is, nevertheless, which a pipe organ is playing, its response is very even over the of a soft, swishing nature, caus­ and while a fair tone is obtained, entire musical range; in fact, any ing little interference or unpleas­ a considerable amount of the variation from pure straight line antness. Response is pleasingly overtones and low notes are miss­ reproduction is caused not by the even over the entire musical ing. inertia of the cone so much as by range. Due to its very rigid (Note-For the purpose of the limitations of the driving clamping, blasting and consider­ comparing the tone qualities of unit. Due to the lack of f1exture able distortion may occur if 'it is sets and reproducers, piano or in the cone, its tendency to cause pushed to too great a volume pro­ pipe organ music is best, as the paper crackle with static dis­ duction. For ordi,nary home use, widest possible bands of funda­ charges is negligible. The cone however, this last consideration mental tones and overtones are in this type of talker is generally may be entirely disregarded. (Please turn to page 48) 20 RADIO AGE for October, 1926 The Magazine of the Hour Use Tube Socket as Plug for Testing Receivers By CHARLES E. FELSTEAD HE tube socket plug shown ( Radio 6CUj melted sealing wax. Before put­ T in A in the drawing can be ting the sealing wax in the base, put to a large variety of sets and finding trouble in his old small glass beads, or short uses. Only two uses will be given sets. The plug can be made by lengths of spaghetti tubing, can , here. If the experimenter has breaking the base off a burned be put over the wires to make several of them on hand, it will out tube, soldering long leads to certain they are insulated from ~ave him a tremendous amount of the wires attached to the pegs in each other. Three or four foot muss and work in trying out new the base, and filling the base with lengths of flexible insulated lamp cord can be used for the leads. If the experimenter has one set hooked up and wishes to tryout another set, he can connect the two A battery leads and the plate lead of the tube socket plug to the battery binding posts on the new set, and put the socket plug into the detector socket of the set that is already hooked up. Then all he needs do to test out the new set is to short circuit the phone binding posts on it, and connect the aerial to it, as shown in B of the drawing. In this manner, new sets can be tested out with­ out disconnecting the regular re­ ceiving set. By connecting a voltmeter to the two filament leads, as shown in C, the socket plug makes it easy to find out ex­ actly how much voltage is being applied to the filament of each NEW SE.T tube in the set. FIG.''A RADIO AGE for October, 1926 The kfagazine of the Hour 21

"The Ladies- God Bless' eml"

By DOROTHY BRISTER STAFFORD

RS. McINNIS is presi­ M dent of the League of Women Voters, an ar­ dent radio devotee- that is, she listens to all the special women's programs that hurry busily hither and yon through the air in the mornings, likewise the phil­ harmonic concerts and university extension lectures-and has even enjoyed the thrill of the micro­ phone herself, when she has Johanna Grosse shown in the pensive mood above is the concert organist at station WL W, Cincinnati given to the waiting world some of the salient features of her well­ known lecture, "Are the Cinema and the Radio a Menace to the look on life. We can never quite Opie Read"?) but what we Rising Generation?" and she was get it right, and small wonder, started to say is that there re­ taking us severely to task for our for it must have been when we mains, heaven knows why, as a seeming inclination to ignore the were somewhere around the plas­ hang-over from those dim, dis­ great place women were playing tic age of sixteen that we suf­ couraged solemn days of youth in radio broadcasting. fered from a violent attack of this choice fragment: We never come in contact with Ella Wheeler Wilcox- (why is it, Mrs. McInnis and the various we wonder, that at that age one's "The"e's not a thing in heall en or feminine pies in which she has a mind ran to "The Ballad of Read­ earth, finger, that one little, semi­ ing Gaol," "The Moving Finger There's not a Ute, a death, a atrophied brain-cell doesn't try to Writes" and like bitter doses, and birth, function and bring to life a quo­ today leans to such classics as There's not a feathe"'s-weight of tation that seems so admirably "The Hermit of Shark Tooth worth adapted to this lady and her out- Shoal" and "Said E. P. Roe to Without a woman in it." 22 RADIO AGE for October, 1926 The Magazine of the Hour And if such a sweeping statement isn't because, in many cases, profession, as in the interesting of feminine omnipotence could broadcasting, with its unstabil­ case of Rosaline Greene, who for come out of the Mid-Victorian ized and rather vague remunera­ two years was leading woman era, how much more true it tion, is regarded merely by most with the WGY Players. It prob­ should be in this, Mrs. McInnis' women artists as but a stepping ably never occurred to the a ver­ day, when enthusiasts of her like stone to the legitimate stage or age listener, who followed Miss are rampant throughout the land, concert platform, an opportunity Greene's very creditable work seeing that no opportunity goes for publicity that leads to a more with this popular organization ungrasped that may further their secure and established position. that the young woman was other crusade of glorifying the fem­ Thus, in many instances, we have than an actress by profession­ inine cause. And since she had just become nicely acquainted when in fact she was a student at put it into our head we began with a charming voice as some New York State Teachers' Col­ seriously to wonder why the fair station's regular feature, when it lege, preparing herself for a sex is not playing an even more vanishes from the air, gone we teaching career. With her grad­ prominent part than they are in know not whither. If the singer uation last June, she said fare­ radio circles. For when it .comes has achieved big-time vaudeville, well to the microphone, and this to real achievement, in numbers she is lost to us forever, by rea­ will undoubtedly be the course at least, the feminine entertain­ son of the ban against broadcast­ taken by many able women work­ ers seem to be lagging behind ing. ers until the puzzling problem of their brothers in the matter of May Be Side Issue who is going to pay for our. radio established popularity and as­ A GAIN broadcasting may be a entertainment has a solution. sured success in the radio world. fi side-issue with a young We timidly hazarded our opin­ One wonders, perhaps, if it woman preparing for some other ion that the dear girls weren't making as big a splash as they might, and put forth the fore­ going reason, but Mrs. McInnis fairly snorted her indignation. "Why there are dozens of ca­ pable women performers appear­ ing on the air nightly," she pro­ tested, "and still you seem to be able to find no one to talk about but the men." "All right," we told her, "Go ahead and name a few dozen 0:( the women who have national reputations as radio entertainers equal to those of the men we have been writing about. We aren't discussing their ability-it's the fame they have acquired in this new profession." Our critic started bravely off with a few well-known names from the large stations, a local celebrity or two, who are un­ known two hundred miles from home, and wound lamely up with a number of grand opera stars she had heard the past winter. "But you can't call Schumann­ Heink and Homer radio perform­ ers, can you?" we asked her, and when she realized how relatively few women had achieved what might be called a lasting place in broadcasting, she had to admit Lattice Howell, coloratura soprano, late of the Capitol theatre that her argument was extremely and recently heard through WSMB at N ew Orleans wobbly. "But why is it?" she persisted, RADIO AGE for October, 1926 The ]';[aRazine of the Hour 23 "aside from the fact that you say they aren't paid enough to make them stick to it?" We had what seemed to be an illuminating idea. "Attend," we told her. "Ra­ dio seems to be essentially a mas­ culine pursuit, doesn't it? And have you ever yet met a man who didn't have the sneaking, low­ down trick of turning off a so­ prano before she had a chance to convince him that she was worth hearing?- The girls simply don't get an opportunity. It seems that vision is necessary to carry charm to the average male and it takes a peculiar sort of person­ ality to put a woman over when she is invisible to the eye." Mrs. McInnis sighed, and agreed that, alas, it seemed to be true. Stage vs. Radio HEN the two of us cited a T number of vaudeville and light opera stars whose greatest asset is. personality and decided that all of them might be miser­ able flops as radio entertainers despite the fact that they are headliners upon the stage. We " Bernice" (and she's nice, too) popular pianiste at station WCX. Detroit recall a young woman imperson­ ator, persistently exploited by one of the great stations recently, on these aids than her huskier the Capitol program. The selec­ who probably in a visual appear­ brother. A good, honest, hearty tion was, of all things, the Blue ance had a wide appeal through baritone voice needs neither Danube Waltz-an opus we have her charm, but though we lis­ camouflage nor personality to always contended that needs tened to her many' times in an make it register. But much is oodles of dreamy violins and 'cel­ effort to discover just why she forgiven a beautiful woman, and los to bring out its exquisite should be featured by a station ofttimes a thin soprano or off-key rhythm-and it was being sung with extremely high standards as contralto goes over big on the from the theatre stage with full to the quality of its broadcasting stage by the sheer force of its orchestral accompaniment by a -to us she registered absol ute owner's personality. coloratura of fine tone beauty and zero as a radio attraction. We We had a pleasing experience an ~xceptional range. We were had nothing to judge her by but one night early in the summer so impressed that we immedi­ her voice, and that was very bad. that demonstrated how much im­ ately got busy, and found that the When one realizes how much at­ portance we listeners attach to a voice belonged to Lottice Howell, tention is given to a stage artist's familiar voice upon the air. We a name heretofore unknown to wardrobe, scenery and lighting like to hear the people we have our musical experience. From effects, the importance of the pic­ come to know, just, as casting the breadth of tone and apparent ture in bringing the entertainer our eyes over a vaudeville bill, years of culture, we mentally success is so evident, that it is we are most likely to be inter­ placed Miss Howell as a grand small wonder, that stripped of ested if the name of a familiar opera singer of at least forty, of all these accouterments, it is only turn appears thereon. It must regal embonpoint and unmistak­ the occasional lucky one who reg­ have been something over a year ably a blond. When the obliging isters with the radio listener. ago that we became quite enthu­ press agent came across with a And there is no question that the siastic over an exquisite soprano photograph we almost fell off our feminine entertainer relies more voice that turned up one night on chair to find that the voice be- 24 RADIO AGE /or October, 1926 The Magazine o/Ihe Hour

longed to what seemed a mere mate manner, and the announc~ ucation began at the mature age child of twenty or so, possessed ers have succeeded in working up of six. Coming to this country of unusual personal beauty, and almost as much mystery about when eleven, she studied piano at showing not a sign of the years her as surrounds the w. k. gen­ the Cincinnati College of Music, of strenuous labor that must have tleman in the Silver Mask. To but has never had an organ les­ gone into perfecting a voice of our notion she can do just as son in her life. A year later she such unusual purity of tone and much with a piano as any of her embarked upon her career as a flexibility of handling. masculine contemporaries, and if theatre organist, surely one of one can put any faith in what her Lottice at WSMB the yougest professionals of her enthusiastic announcer tells us, time. Her prestige as a master RESENTLY came that night she is just as popular. of this intricate instrument grew Plast summer when WSMB, At WLW, Cincinnati, there is with the years, until now she is New Orleans, was having one of a young radio entertainer not in demand whenever a great or­ its periodical fits of coming up only of unusual ability, but of re­ gan is to be dedicated in a church, like thunder from the gulf. The markable personality, and since temple or theatre. program was from the Strand she is so fortunate as to be fea­ It is not our contention to pre­ theatre, and the room was filled tured by a station of great power, sent these aforesaid young with tones of liquid beauty that her audience of appreciative lis­ women as the only successful we · would have recognized had teners equals that of any of the feminine radio entertainers. Ho~g-Kong been broadcasting great eastern stations. She is They are merely a few who by them. It was Lottice Howell fill­ Johanna Grosse, concert organ­ widely different means-though ing a special engagement at that ist, and while few girls would se­ all are hard and zealous workers theatre, and we were as delighted lect an organ as the instrument -may be said to have really ar­ at happening upon her again as to bring unusual fame-our great rived in this new and rather dif­ though she were a friend of many organists being almost without ficult profession. If we were so years' standing. We were disap­ exception of the masculine per­ fortunate as to possess a radio set pointed to learn, however, that we suasion-the surprlSlllg tech­ such as seems to be owned by al­ were to have her back but tem­ nique and mastery of the m ulti­ most every newspaper reviewer, porarily, as she is this winter to tudinous keys displayed by this where, judging from the reviews, sing the prima donna role in young woman, placed her almost one may hear a dinner concert in "Deep River," an Arthur Hop­ from the time she began broad­ San Francisco, run up to Seattle kins production. Incidentally casting in the f ront rank of radio for' a bedtime story, listen to a those loyal southerners down at entertainers. French lesson in Boston, the WSMB claim to have discovered Municipal Band in Havana, and Miss Howell long before Roxy Request Numbers get back home in time to follow did. E first became interested in the New York hookup, we might An attractive young woman Wher when we happened in on get acquainted with more enter­ known simply to listeners as a pr ogram where she was com­ tainers. But since our listening " Bernice," in the two years dur­ plying with requests that seemed is restricted to what comes over ing which she has been a r egular to come from all over the radio the best commercial set we can member of the studio staff of wor ld, and it was at first mere buy, which, even when doing its WCX, Detroit, has gathered to surprise that such a multitude of noblest seems to be limited to herself a great following of those listeners should be interested in only twenty-five hundred miles, listeners who enjoy' jazz piano organ music that prompted us to and as we have a queer prejudice playing when executed by one stay by the Crossley station long against hazar ding an opinion of born with the gift for the trick enough to realize that .J ohanna an artist to whom we haven't orchestrations of modern music. Grosse was far from being the personally listened, it is not pos­ " Bernice" may be regarded as a average studio organist. She sible at this time to pass judg­ veteran broadcaster, for she seems to have an unlimited reper­ ment upon the feminine stars of started as accompanist at the toire at her gifted finger tips, the entire country. Free-Press station when a mere and a singular genius for extract­ Mrs. McInnis has been looking child, and as her popularity grew, ing all the melody possible with over the photographs. "I begin extended her work to recitals and a technique peculiarly her own, to understand," she said, "why request hours, and became the from the great organ. And the my Harold is so set on becoming star of WCX's weekly revel, "The story of her life carries out one's an announcer . And it would be rather a pity if these young Red Apple Club." In addition to fi rst impression-that of an art­ women had to spend their lives her radio work "Bernice" makes ist born with a genius for one in­ shut up in broadcast studios player piano records and demon­ st r ument. Born in Hungary in a where no one sees them but the strat es the same. She has al­ small village between Vienna and announcers." ways been presented in an inti- Budapest, Johanna's musical ed- And wouldn't it? RADIO AGE for October, 1926 The illa-gazille of the Hour 2S

Converting Station 9BHX To Crystal Control Set Better Note and Con­ stant Frequency Ob­ tained Through Change

By F. A. HILL old transmitter somewhat but we INCE the description of the (f!.Nociale Editor) Sshort wave, low power, would still have been far from transmitter by the writer in our ideal of having a constant the August issue of RADIO AGE, In this article we have doubled signal with the pretty crystal we have made a change in the the voltage, using World storage tone like 4BY, 4XE, 2MU, 9MO, 9BHX set, going from the single B batteries, 4 additional banks 8PL, 9AOT and a few others seven and a half watter as an of 45 volts, bringing our total up whom it is a pleasure to work on oscillator, to the crystal control, to 360 volts. Such an increase account of the permanency and crystal oscillator, power amplifier of voltage would have helped the clean cut signal. combination. Quite a number of combina­ Results have been more than ili··· .. ·~·:·;~~··~:;··;·;~:·~:·; ·~~:; ·· · · .. ~ tions were tried out before the gratifying. Where with the old l final arrangement was decided arrangement the signal was fair ~ i 1 Thordarson 8~' volt filament I ~ I upon. For the benefit of those enough considering the low I ~ I transformer . who are just entering the crystal power, yet there was much to be )!I 3 Benjamin cushion sockets (new stage we will recount some of the "1 type for UX bases) desired in the way of stability. 3 Alle.n-Bradley fixed resistors: details in the conversion of a set 1l Swinging of antenna, or the pres­ i ~ Figure 3, RI, 50,000 ohms; from the simple oscillator to the ence of body capacity made suf­ I; R2, 25,000 ohms; R3, 10,000 crystal oscillator, power amplifier ficient change in the signals to ' ~ I ohms combination. render them unstable. With the :1 1 Crescent lavite resistance R4, 10,000 or 5,000 ohms use of crystal control this trou­ ~:::::: I Jewell meters: RFA 0-1; RFA Position of Crystal ble has been eliminated and re­ 0·2; RFA 0·3; RFA 0·3 (an· y referring to Figure 1 in the ports now show 9BHX from R5 tenna); MA 0·100; MA B blueprint section you will to R6 at distances from a thou­ ~ I 0.250; MA 0-500; AC volt- observe the elementary layout on sand to two thousand miles. So ~ I 5 Sa:;::o O-~~pass condensers which we first experimented. far nothing has been accom­ ~ I 2 .002 and 3 .006 mfd. I' The crystal, with a fundamental plished on trans-oceanic trans­ ~ 2 Electrad bypass condensers CS ! of 3700 kc. was secured from our mission but with a little more :: and CG, 1 mfd each :: friend 4BY who couldn't rest in time to spend it is believed ~ I 3 Cardwell condensers CI, C2 I ~ peace until 9BHX was converted III 8 and C3, .00025 mfd. each I ~ greater DX can be secured. to crystal control. It oscillated In the August issue the plate easily and freely at that fre­ voltage was given as 180 volts. L..:~::~,:'~,~,,~~~:~::.~:':::}i quency and was easily put into

28 RADIO AGE for October, 1926 The Magazine of the Hour operation as a simple crystal os­ to 5,000 if it is desired to give one, while the crystal fundamen­ cillator. more power to the 201-A which tal dip is abrupt and very decided. Grid to filament position of the acts as a crystal oscillator. When By using a zero to one RF am­ crystal was decided upon after the power is put on the crystal meter in series with one side of numerous tests with the grid to circuit alone the plate mills will the tuning condenser, as shown plate scheme, the latter not giv­ read about 35 to 50 mills with the in Figure 1, will give maximum ing nearly as much power as the crystal not oscillating. By vary­ RF reading when the mills in the former, although perhaps a trifle ing Clover its range and watch­ plate circuit are at a minimum. steadier in operation. The RF ing the milliammeter closely there While the use of the two meters choke shown in the first tube cir­ will be found a position where is nice, if the pocketbook does not cuit in Figure 1 was made up of the plate mills drop sharply to permit, the DC milliammeter may 150 turns of No. 30 wire on an about 15 to 20 mills. Capacity be retained and used as a guide inch form, (cardboard tube). changes above and below that to indicate the oscillation point of The resistance in series with it position will read 35 to 50 mills. the crystal. was an Allen-Bradley 50,000 ohm This is graphically comparable to fixed resistor. The resistance a V figure in which the non-oscil­ Getting Crystal Going value between grid and filament lating conditions (35-50 mills) AVING tuned the inductance in turn limits the plate mills of are at the top of the figure, and H L1, (made up of about 12 that particular tube down to a the oscillating condition (15-20 turns of No.6 gauge aluminum reasonable value. The same ob­ mills) at the bottom of the V, or or copper wire, wound on a 3 inch ject may be obtained with C bat­ the point of lowest dip. Crys­ form tightly, then allowed to slip; teries as shown in the schematic tals which oscillate freely and do then spaced as shown in Figure circuit Figure 2, which is the not have any obvious parasitic 4-C) to the . fundamental of the same as Figure 1 with the excep­ fundamentals, will show only one crystal, which in this particular tion of the C batteries used for dip, while crystals which have case was 3700 kc, we find max­ biasing the different grids. parasitic fundamentals close to imum RF current in the tank cir­ In order to tell when the crys­ the' main fundamental will have cuit with minimum mills in the tal is oscillating we used a zero an irregular dip. Crystals which plate circuit. Under these con­ to one hundred DC milliammeter need a regenerative coil in series ditions the crystal is oscillating (Jewell) in series with the 360 with them to cause oscillation, nicely and we are ready to trans­ volt battery. Between the meter will show two dips, one for the fer this constant frequency en- . and the plate circuit is a 10,000 coil's period, and one for the fun­ ergy to the next tube, or the fre­ ohm Crescent Lavite fixed re­ damental of the crystal. But the quency doubler as it is called. sist"or. This value can be changed dip of the coil will be a gradual A Sangamo .002 works very

In this photo is shown the short wave receiver now used at 9BHX RADIO AGE for October, 1926 The Magazine of the Hour 29

Inspection of this photograph will show the manner of placing the apparatus used in conversion of 9BHX t o crystal control nicely for the coupling condenser j, ...... '''1 frequency doubling. This circuit and it stands up exceedingly Parts for Receiver should be used with maximum well under heavy RF currents. I ~ I I ~ RF current and minimum plate ~ Silver Marshall plug in coil ~ I The inductance L2 is wound in = and socket I:: mills-there is a definite point the same manner as L1, only it 1 at which best results are secured. has but approximately four to six 111 Ca;ta~:I~o·:~::s:~ mfd. taper I! With the plate circuit of the turns. The RF choke in the grid I ~ .: Silver-Marshall short wave con- I ~ I second tube, or the frequency circuit of the UX112 is wound I :1 denser I' : doubler, amplifying at 7400 kc : Silver-Marshall midget con- :: the same as RFC1, but the re­ we now wish to transfer this en­ I~ i dense~ for antenna coupling I ~ I sistance R2 is a value from 10,- ergy to the antenna circuit, but 000 to 50,000 ohms. The plate 1,l i ' AI~~:ta!::~I~~e~5,OOO ohm re· !!I since probably the energy is not l circuit of the frequency doubler . 2 Amperite Rt for UV 199 from very strong at this point, we will is the same as that of the pre­ put it through a power amplifier Ii! ~oI:~Its; R2 20l.A from 6 III ceding tube only for a shorter which in this case was a UX210 wave. An RF ammeter in the ;: 1 Sangamo .00025 rnfd. grid con- I ~ I operated from a 6 volt storage tank circuit and a DC milliam­ I. denser and slips for leak "I battery. Where the crystal tube meter in the plate lead will give II ',.~ :I Durham 7 megohm grid leak I ~'. 'I had an Amperite 1A in its fila­ you an idea of the working of this General Radio audio trans- ment, and the UX112 has an Am­ circuit. Condenser C2 is run : ~ II Jo!::me:ultiplug and base i ~ perite 112 in its filament lead, over its range until current rises there is none in the 210 filament in RF A 2. This current will be so it receives full 6 volts. This 1,. 1 2 Tw:o~~ti;:shposts lii,.· 1 at the second harmonic of the 2 Silver-Marshall sockets is about a volt and a half below tube, the grid circuit being at the the normal operating point of fundamental (or first harmonic) this tube's filament, but it will 3700 kc, while the plate circuit serve unless you happen to have will be at 7400 kc. This is called t: ~:~~~:~:~~~~:~~:;·':::: 11 an eight volt storage battery, or

32 RADIO AGE for October, 1926 The Magazine of the Hour desire to go to AC filament opera­ white hot. A slight red glow will slightest difference bet wee n tion as is shown in later figures not be harmful but do not let the grounding the filaments and not in the blueprint section. plates get white hot. grounding them, but for sim­ The output of the 112 is at Figures 1 and 2 will give you plicity we left them grounded. 7400 kc, the input of the 210 is all the data necessary on the at the same frequency, and the small tube arrangements, the Antenna is Vertical emitted wave in the antenna cir­ latter bl ueprint showing C bat­ A NTENNA used was a single cuit will be the same. There is teries instead of resistances in 11 wire, vertical, 32 feet long. also a definite point in the tank the grid circuit. A total of about Counterpoise 32 feet, horizontal. circuit of the 210 where you win 90 volts (perhaps 120) will be re­ Eight turns of L4 as coupling, get maximum RF reading with quired for this purpose. From this coil being the same diameter a minimum of plate mills. This 22 to 45 will be used on the crys­ (4 inches) as the other induc­ energy is inductively passed into tal grid; from 45 to 60 on the fre­ tances in the set. Capacity C4 the antenna circuit L4, equipped quency doubler grid, and from 60 was .00035 mfd although it may with an RF ammeter and a vari­ to 90, or possibly 120, on the grid be .00025 if more turns are added able condenser. Where induc­ of the last power amplifier. to L4. Capacities C1, C2 and C3 tances L2 in the 112 circuit and Unless all circuits are tuned were all .00025 mfd-any good L3 in the 210 circuit are from 4 exactly to resonance with the make of condenser will do. The to 6 turns of wire, L4 may be crystal circuit there is a possibil­ photograph of the transmitter on from 6 to 8 turns, depending ity of oscillation in the amplifier page 29 will give an idea of the upon the amount of coupling re­ tubes, and this is destructive to manner in which the transmit­ quired to properly transfer a a good signal, so be sure that all ter was laid out. Since photo­ maximum of the energy to the tubes are functioning as ampli­ graphing the set, some of the antenna circuit. Slight changes fiers instead of oscillators (ex­ wires have been put in perma­ in the tuning of L4 will react cept the crystal tube which of nently, made up of No.6 gauge back on the tuning of L3 and course is supposed to oscillate). aluminum wire-it is big enough thence to L2, but after carefully Going over to the use of so it is stiff and solid. Since it working at this you will be able UX210 tubes throughout, Figure is not easy to solder aluminum to get the transmitter properly 3 will give the schematic, show­ we hammered the ends which we tuned and then it will remain in ing the use also of AC on the fila­ desired to connect to other points, resonance through the whole set ments through a Thordarson 8% and after hammering them out without having to make changes volt filament transformer. The flat drilled a hole through the flat all" the time. Antenna coupling operation of the set is the same section for screw assembly. This may be from a half inch to inch as before with the exception of gave us tight assembly and very depending on the power. larger tubes, and keying in the good contact. plate supply of both the fre­ Figures 4-D and 4-E give two In the assembly of Ll, L2 and quency doubler and the last forms of crystal holders, the one L3 we found it very advan­ power amplifier, instead of the in sketch 4-E being designed by tageous to keep the distance be­ last P. A. alone as was the case J. E. Hodge of 4BY. It is not tween these inductances at least in Figure 1 and 2. required that very much pressure 18 inches. This elim"inated any Radio frequency chokes in Fig­ be placed on the crystal which fits trouble with inductive RF feed­ ure 3 are the same val ue as here­ between two smooth brass or cop­ back and obviated the necessity tofore. R1 in the grid circuit of per plates. Apparently just the of neutralizing between the fre­ the crystal may be from 50,000 weight of the upper plate will quency doubler and the power to 100,000 ohms. Resistance R4 generally suffice, although just a amplifier circuit. If you desire in the crystal tube plate circuit trifle tension on top will prevent to economize on space, you will is 5,000 (Crescent). There are the plate shifting due to jarring probably have to neutralize. no plate resistances in the other of the table or other radio room tubes since we wished to get as commotion. Condenser and Resistances. much from the 210's as WIIS pos­ Schematic circuits 4-A and YPASS condensers of a .006 sible without injury. Bypass 4-B show the receiver circuit. B value (Sangamo) are pro­ condensers described previously the first the throttle control vided as shown in the schematic. are the same in this arrangement. Armstrong and the second the Resistance R5 may be a 5,000 or The coupling condensers are the Weagant. We have several times 2,500 ohm Crescent Lavite, the same. Resistance R2 will run arranged these receiving circuit same as R3. Radio frequency from 25,000 to 50,000 ohms, while so that a single pole double chokes 5 and 4 are the same as the resistance R3 will run from throw switch would switch from RFC 1 and 2. Keying is accom­ 5,000 to 10,000 ohms. Two Elec­ one to the other. So far we have plished in the plate lead of the trad or Dubilier one mfd bypass failed to find enough difference last power amplifier. Resistance condensers are shown from ends between the two to cause us to R6 is anywhere from 5,000 to of the filament secondary to cen­ show a technical preference, al­ 25,000 ohms. Keep changing re­ ter tap, which is common with though we have a personal lean­ sistance values in the grid cir­ all grid returns, negative B, and ing towards the Weagant. The cuits until you get maximum out­ ground, the latter if desired. phones are totally isolated from put without the tubes getting With us it did not make the (Please tum to page 85) RADIO AGEfor October. 1926 The ilfagazine of the Hour 33 Raytheon Design/or A Be Po\ver Unit Type BH Tube Gi()eJ" Increase in Volt­ age and Current EVELOPMENTS of the By .Miles Pennybacker' ter circuit consists of two choke D new type BH Raytheon coils capable of can'ying at least rectifier now makes it pos­ 85 milliamperes D C and having sible for the first time to satisfac­ an inductance of at at least 25 torily obtain A. Band C voltages '~ henries per choke at this value of from the alternating current light D C. Thordarson, General Ra­ socket. The radio experimenter dio, Amertran. and several other and set builder have long awaited manufacturers are now supply­ the opportunity to obtain a recti­ ing these choke coils. The filter fier which would have sufficient condensers are arranged as current and voltage capacity to ~ shown in Figure 1. This first f light the filaments of 199 type / section condenser C, has a capa­ radio tubes in series. and at the city of 4 microfarads. C. is 4 and same time supply sufficient plate C, is 6 microfarads. voltage to operate a power amp­ Resistances f or Control lifier. The new Type BH fulfills these ESISTANCE control unit requirements in a particularly Rwhich is used to determine satisfactory manner, and there the various B voltages for the remains a reserve of power from receiver and to drop the B pI us which the radio set may draw at maximum voltage to that value momentary overloads, without required by the filaments in ser­ fear of burning out the tube or ies, presented quite a problem in impairing the quality of repro­ development. This situation ex­ duction. isted because practically no In order to clearly see the pic­ manufacturers of resistance units ture made possible by this new had conceived the demand for the development, let us look at Fig­ types required particularly in the ure 1 which is a schematic draw­ caSe of variable resistors. The ing of a Raytheon A. B. C. power great difficulty was to find resis­ unit with the Type BH tube. The tors of sufficient current carrying power transformer is built to capacity and wide enough range supply 350 volts on each side of of resistances to be of value. the high voltage secondary wind­ This is the new BH Raytheon tube wh'ch (AiIen Bradley now makes them. has a materially higher current -Editor). ing at no load. The current car­ and voltage output rying capacity of this winding The ideal unit for this service 'should be at least equal to 85 across each half of the trans­ would be a variable resistor of milliamperes. and in order to in­ former secondary as shown in at least 60 milliamperes current sure good regulation in keeping Figure 1, by C, and C" The fil- carrying capacity and a resist- with that already determined by the Type BH Raytheon. the re­ gulation of the power transfor­ mer should not be more than 10%. The power transformer also has a filament supply wind­ ing which delivers five volts at .5 amperes for the filament of a UX 112 or a UX 171 power ampli­ fier tube. The usual buffer condensers of .1 microfarad capacity are placed Figure 2

"Chief EngineEr Raytheon, Mfg. QQ, IJ I 34 RADIO AGE for October, 1926 The Magazine of the Hour ance range of from 2500 to 5000 acteristics are of an extremely recommended Raytheon circuits ohms. One arrangement which technical nature, and can best be are adopted, the only regulation was used to achieve the degree of appreciated from a comparison of the power supply circuit will control required was a combina­ of the new Type BH tube with be that of the transformer and ation of a Ward-Leonard fixed other rectifiers designed for B­ filter circuit. There will be no 3000 ohm resistance R. in series power service. JOss of voltage due to changing with another fixed resistance R. characteristics of the Type BH. of 5000 ohms, around which was More Powerful Tube This feature in itself is really re­ shunted a third resistance, R •. OR example--if a B-power markable and one which has R, has a variable resistance of F supply which has hitherto never before been incorporated 2000 ohms, maximum value. been equipped with a TtYpe B in power supply rectifiers. Several potentiometers on the is now equipped with one of the In order to take advantage of market, will fill this position new Type BH tubes, there will this good characteristic, the con­ altho there are none which have be an average increase in voltage structor of the unit may well yet been specifically designed for output from the power supply pay attention to the proper de­ the circuit. The value of the re­ unit of 30 volts for any given sign of its power transformer maining resistances in Figure 1 radio set. When adjustment of and filter circuit, with regard to are shown in drawing, and are the radio frequency and detec­ loss of voltage caused by poor re­ the customary B-power supply tor voltages is made, reducing gulation. specifications such as have been them to their previous values, An opportunity to improve the approved by the Raytheon labo­ there will be a further increase regulation of the filter circuit ratories from time to time. in the voltage output of the pow­ may be found in condenser C, of The filament of the power am­ er supply unit, of from five to fif­ of Figure 1. By increasing this plifier tube, being supplied with teen volts. This high voltage is capacity from 2 to 4 micro­ raw A C has a 400 ohm poten­ of course available and extremely farads at 85 milliamperes, an in­ tiometer connected across its ter­ desirable for use in connection crease in D C voltage output of minals. The center tap of this with the power amplifier, and approximately 15 volts may be potentiometer is returned to B for this reason and others, it is secured. minus, and is set at such a posi­ not advisable to use any rectifier Reserve Power tion as to give minimum A C but the Type BH. TILL another feature of the hum. The "c" voltage for the Another feature of the new S Type BH which is of consid­ power amplifier is obtained from rectifier which is of great import­ erable importance in obtaining a variable resistor, R" connected ance in connection with the A. high quality reproduction, is the as shown in Figure 1. In order B. C. power supply unit, is the reserve power available for mom­ to obtain 45 volts battery improved regulation of the tube "c" entary overloads without damage from this source, it will be nec­ itself. Actual measurements in to the rectifier. Extreme bursts essary that R, have a maximum the Raytheon laboratories have of volume from the speaker de­ resistance of at least 600 ohms. shown that the new tube has a mand proportional amounts of The performance of the A. B. constant voltage drop from a energy from the power supply C. power unit is to a very great very low current up to 85 milli­ unit. If this energy is not avail­ degree dependent upon the char­ amperes. If the output from the able at a constant voltage, there acteristics of the new Raytheon rectifier is never less than 10 mil­ is certain to be distortion and Type BH rectifier. These char- liamperes, as will be the case if a considerable loss of quality. If the power supply unit is pro­ perly designed with regard to regulation, and if the rectifier is capable of delivering these peaks of energy without loss of voltage, good reproduction is insured at all times. The various constants shown at the end of this article enable the builder to construct a power supply unit of good regulation, and by using the Raytheon Type BH he will have achieved all that is to be desired. For those who are not thor­ oughly familiar with the meth­ od of connecting the filaments A.C Fi"bmenf" .Jvpp(y of radio tubes in series, Figures /or f'b"",r Amp/iller Tvb~ 2 and 3 will be of interest. Two methods of making these Figure 1 connections are possible. First using the voltage drop along the III RADIO AGE for October, 1926 The M agaz{ne of tlze iiour :is various filaments as a source of grid bias, and using no grid bias on the various tubes. The first method is better from the stand­ point of the amount of amplifi­ cation secured and is possible when the degree of filtering of the power supply unit is very good. The filter circuit shown in Fig­ ure 1 gives excellent filtering, and the user of this unit is therefore Figure 3 enabled to make use of the grid biasing method shown in Figure C_6 mfd. condenser. it admirable for handling traffic. 2. Where the degree of filtering C" C, & C-l mfd. condensers. For short wave broadcast work is not sufficient, it is better to A-O to 75 m. a. milliameter. such narrow limits are not re­ connect the grid return leads of L--25 henries at 85 m. a., d. c. quired. the various radio tubes to the T,-Thordarson Transformer Parts used in the transmitter negative side of the respective supplying 350 volts per anode. shown in Figure 3, and the re­ filaments. In general, this scheme T,-Thordarson Transformer ceiver shown in Figure 4-B are is much less difficult to handle, supplying 5 volts at Y2 ampere. shown elsewhere in this article. altho it gives a lowered overall The resistance R3, in Figure 4B amplification on account of the Converting Station 9BHX to and 4C was 25,000 ohms and was necessify of reducing the plate Crystal Control Set used instead of a RF choke coil voltages on these tubes without (Continued from page 32) since it was found to be free from negative grid bias. the plate circuit by means of a a period of its own, which is gen­ Four Year Research discarded audio transformer, any erally not the case with the RF The type BH is the culmina­ ratio seems to do. choke coil. tion of four years of concentrated Receiver Coils - We would be glad to hear from research on one problem. N winding coils for the re­ other amateurs who have had ex­ Current rating--85 milliam­ I ceiver, these are wound on a perience with either the forego­ peres output, an increase of 40 0/0 blank, threaded, Silver-Marshall ing arrangement or a similar over the well known Type B. coil form of the plug in variety. one. The station is now using Voltage rating-200 volts, an We wound the secondary double two crystals, one on 42.21 meters increase of 33 % over the well spaced, and the tickler winding and the other on 40.52. The lat­ known Type B. single, as is evident from a look ter is generally used for traffic. Voltage drop due to rectifier­ at the picture on page 28. For The wavemeter described by F. practically constant from 10 to the secondary we used a Card­ H. Schnell in the September issue 85 m. a. (This is in sharp con­ well 191-E taper plate with a of RADIO AGE is exceedingly trast to the filament type of rec­ minimum capacity of 5 picofarads handy for use in connection with tifier, which often requires a volt­ and a maximum capacity of a transmitter, while the grid age regular tube.) .000075 microfarads. For the re­ meter driver written up by W. This tube marks a real advance generati ve condenser we used one H. Hoffman in the same issue will in a. c. operation since it is a of the new Silver-Marshall type also repay its builder for the practical solution of lighting made especially for short wave trouble because of the number of Type 199 filaments from a. c. work. Antenna coupling is ca­ stunts that may be performed This announcement promises pacitative instead of inductive, with it. The wavemeter, reso­ to be of equal significance to the because with our constant chang­ nance type such as was described radio public as was the original ing of antennas we found the ca­ by the writer in the August blue­ announcement of the Raytheon pacity coupling easier. The sec­ print section was used to pick up rectifier, one year ago. ondary of the coil for the Amer­ the fundamental as well as the The constants covering Figure ican band is wound with 13 turns second harmonic of the crystal. 1 are: of No. 28DCC double spaced. The Minimum number of meters re­ R,-Ward Leonard 5000 ohms. tickler windirig is 10 turns, sin­ quired: one good wave meter ; one R,-Federal No. 25 Potentiom- gle spaced. With this coil and DC milliammeter 0 to 500 mills. eter. the Cardwell condenser shown, With these two you can get R_Ward Leonard 3000 ohms. with a UV199 tube, our range started, but with more meters R,-Clarostat. was from about 6900 to 7900 kc. you will have to do less guessing. R-Bradleyohm No. 10. Station 4BY on 6960 kc was If using only the 0-500 mills R.-I0,000 ohm fixed resistor. found at 20 degrees on a Na­ meter then use it in series with R. & R,-General Radio No. tional vernier dial (dual range) the negative B so it will register 141 Potentiometers. while WIZ on 6970 kc was found for all circuits. With the fre­ C, & C-o.l mfd. condensers. at 87, giving practically 67 de­ quency doubler and the power C,--4 mfd. condenser. grees for tuning over the Amer­ amplifier off you can find the C,--4 mfd. condenser. ican 40 meter band, which made crystal dip. 36 RADIO AGE for October, 1926 The Magazine of the IIo1tr

Radio to Control 11 ,000 Mil~s TRY of Railroad Trackage (Continued f r om page 16) SELECTONE 1805 fixed condensers (.002 mfd. TRANSFORMERS 5000 volts). ~J~ C-5 C-6 Faradon model T fixed AT OUR RISK! condensers (.00250 mfd.). :::j;RODUCTS C-7. Fixed condenser (.25 to AS DESCRIBED IN THIS ISSUE . .5 mfd.) 1000 volts. R. Grid leak Ward-Leonard , ; A~;J,"r- I ..£i , MIi.NT! 5000 ohms (100 watts). K. Key-Western Union or m. Mesco. M. A. Jewell Pattern 54 flush mounting 0-1000 (D. C.) (milli­ .F\ ammeter) . V. Jewell t'attern 74 flush mounting 0-15 (A. C.) volt meter ''\. \rl 60 cycles. A \ ::.. J R. F. C. 1 R. F. C. 2 Radio fre- i . \ -,-/ DESIGNED BY E. H . SCOTT quency chokes, 90 turns of No. I wbo t 22 D. C. C. wire wound on a reception of sbtioruo i<.>ent.,d 0,000 or mo • ., lIl i le~ distant. form 1 Vt" diameter-winding 8,OO() MILE RECORD The Quali-Tone Loop pictured above holds SELECTONE FEATURES space 3". I two World's Records for distant reception, Untuned Tr:!Lndorm ... r-R",O()--hll!! f>'!peci:r. lly de­ R. F . C. 3 R. F. C. 4 Radio having brought in stations 8,000 miles away. s~ed d osed iron co.e. wbich limit.!! incc'sbce Write for v erification of these records. Ex­ coulllin@: and i6 imp.etmated in a vacuum I!O ,loll ' clusive Thumbscrew Adjustment keeps all cbarac:telisties of coil remain conshu,t. The I frequency chokes (grid). 12 wires taut always. Guaranteed to improve (:(lil design gh'~ an utremel,y high ampli6cation, Tuned Stage Tran.~ ror",er-R4 1 o-----t. air cme. turns No. 22 D. C. C. wire wound ~~iv;:cePtion of any re- Price $10 E ach tran" former is nu:.tched to ''";tbin one turn hefore ~e;uing in CI,,~e. 'rt,e IlULlchinc of th .... " 6 IT ers on a form Vt" diameter. Lq ~o perfect, .h"t wben~ extreme ~.,lecr;\· ity i!J de,;,.,<1, two <:an b.. lL'''U and are gua.&nteed to match pe'. T. F. Thordarson 150 watt I fectly. This is an e:'l.clus"'" SELECTONE f.,at,,; ... filament transformer. Primary I Either 199 or 201 A Tubes Can Be Used 110 volts, 60 cycles; secondary, No uoleD~;omet"l"$ Il~ newed to stabilize the.e I 12 \'olts, center tap at 6 volts. trll,,-~r()"n, e,.,.. They etln he u.;ed .•eturn the,,, Rnd your money w ill bE I not available from stock. refunded .... Pr;<-e eaeb 56.00. He-"POll>; ihle D""t,ibulor_n...irlLhle lerrilory s till ",·"ilahl". Write or ,,·i,., today. J obbers aI],d Deale,.,.---se,., )'oor D;"'lrihulof or ... rite direct. '3f4G'tr."lJJ]: "'~II'.J"~""'':'-~'''''.!' -"},3" tJ KYW on Crystal Control I Quali-Tone Speakers are unexcelled for Distributo,.,.: Chicago Territoly-E!ectrical Salu I purity of tone and volume. Made in four Co.. (I 8, Clinton 8t .. Chieago: Xew England States­ For Last Thirty Days artistic models priced from $ 1_50 to $25_ Electrical s...1e. Co., 261 Franklin St .. Bo~tQn. M ...". Illustrated liter ature sent upon request. D EVELOPMENTAL work on Quali-Tone Radio Units $6.00 and $7.50. SCOTT TRANSFORMER CO. the conversion of KYW, DEALERS ~~tH~~~~~":.~ ' JOBBERS 9 S. CLINTON ST. CHICAGO, ILL. Westinghouse station at Chica­ DURO METAL PRODUCTS CO. go, to direct crystal control, as Z6S3 North Kildare Annue, Chicago exclusively reported in Radio :...... :. Age for September, has now been completed and the station NEW STATIC ~B~~~ is running at full output rating :: PERFECT FILAMENT CONTROL :: I under crystal control. ELIMINATOR ~ ~ Smith undC!rground aerial reduces static This gives Chicago the only and interference. Enjoy radio all the year. :. Provides complete :- Recommended by lluthorities as t h e best. I directly crystal controlled trans­ Very easy to install. No tools or solder­ :: ~~\~~e;:::~~b:~ ~ mitter West of the Alleghenies, ing require d. To be used with any set. :. without change of con- :- Does away with outside aerial. Price $6.7!i and is a step in the same direc­ delivered. Write Smith's Lab., 676 Euclid :: :ec~~k~l ~~:. ~; ~ tion which all stations must Ave., Beaumont, Tex. :. hole mounting. Self :- eventually take in order to guar­ ~ b~~=;~~~~~=: :: antee their frequency stability. WORLD'S RECORD ~ desired. ~ Many Chicago stations, how­ SUPER 9 6!kn-~Co. ever, are using crystal control All parts in stock. 'Yrite for our .. .. Ioscillators as a means of check­ wholesale prices. :: EJectric CoDU"OUi.lle AppanhUI :: •• 289 Greenfield Avenue Mllwaukc:c:. Wia. .. ing their emitted frequency and THOR RADIO MFG. CO . ::...... •.• .....•.• ... ·.• ...• ... ·.·.·.·.·.·r·.·.·.-". holding it to a standard. a lS CRILLY BLDG. CHICAGO. ILL. P[CUI;C mention Radio Ayc whcn writing to adl'ertisers RADIO AGE for October, 1926 The Magazille of the Hour 37 Uncle Sam Chats with His Dairymen Radio Is a PotentiaL Force in Farm Education By MILTON S. EISENHOWER

VERY American school kid which could have been made pro­ slowly solved by a steady tap, tap, E knows and loves the story ductive, tap of sound facts from various of the canvas-covered prai­ Today, the layman believes sources, rie schooners of the '50's. He that the great agricultural col­ There is no group in America has seen "The Covered Wagon" leges, the numerous agricultural today more eager for up-to-date and he has read "North of 36." experiment stations, and the scientific information than the The attacks of Indians, of rene­ farmers themselves. Overflow­ gade bands, the fury of forest ing agricultural colleges in every and prairie fires have been re·en· H Radio, the newest of inventions, section of the United States are acted in thousands of corn fields, IS proving of great and increasing ample proof of that. But the dis­ usefulness to agriculture. the old­ back yards, and haymows. The est of the occupations of civilized semination of valuable scientific American youngster finds in this man. Not only is it supplying information to a great mass of history his greatest romance-a 'I accurate information in time for people is no easy task; even with the farmer to use it, hut it is giving the young men and women secur­ mental picture of the days of I' ",.!:: I~ brawn's triumph over nature, the rest of the population an understanding of the problems and ing instruction in the agricul­ wild men, and wild animals. But r needs of farming. Everywhere II tural colleges, with the telephone there is one phase of that ro- I;.' farming and the farmer need clear­ and telegraph, the newspapers mance which the boy or the girl headed sympathetic understand­ !i and farm magazines, there re­ does not picture; it is the fact ii ing on the part of the population as a whole. Nowhere in the world mains a gap to be filled. This 1' 1:::.: , gap requires the instantaneous that the first characteristic of the can we have a permanently pros· 1,. 1 American farmer was developed perous civilization. if agriculture and simultaneous dissemination while he fought to hold his staked is unsuccessful and rural life un- ~ I of up-to-the-minute farm infor­ satisfactory. ~,. I mation to every corner of this II In our complex modern life. ~~~ii~ua:h~ct~~~~acW-~:~ic I~~i;~~ I,.: vast country, attacked, there were no tele- ~~1 :~~ul~:tina~~l~~~p~~~:norm~~ ~ ! I together _ Cooperation, not con- ' ~ I' Largest Class Room graphs nor telephones to use to I ::,!"::':':' fiiet, is essential to steady progress. I ~ call neighbors or national guards- ADIO has proved to be the men. When fire swept across his I :n a:e c~:~~:!iO~a~i~l1 c::;;::: I ~ R "missing link" in the chain land, he had to fight it as best he for the permanent betterment of I ~ of media that are used to send could, for no help was at hand. agriculture, once they understan~~ timely information to farmers. Similarly, as obstacle after ob­ ;1 what is necessary_ ~ .. To this end the radio will con- ~ I Today the largest classroom in stacle was overcome, the farmer tribute much. This may be made ~ the world is the United States. had no one to aid him in choos­ a potent means of stimulating ~ I Within its forty-eight states are ing the crops that Were to be il understanding, good-will and co- [ scattered comfortable seats and planted on a particular piece of operation."- W. M. JARDINE, : desks at which the pupils sit. land. There was no scientist to Secretary of Agriculture. ~ ...... ,.... m=.=.,..... , ... j Some are in overalls, aprons; oth­ analyze the soil and designate ers, in business suits, are smok­ whether alfalfa or sweet clover many valuable farm pUblications ing their evening cigars. There would bring greater returns. have solved all the problems are only two things in common Pure-bred cattle were practically which thousands of pioneers did among the individuals who rep­ unknown. Therefore the charac­ not know how to meet, It

Radio Saves Money ACK in 1923 the radio fans W. V. Morris. near McCollum, Georgia, new at the farming business, says that he B at Kansas State Agricultural depends largely upon radio talks for guidance. He owns a 1-tube set College decided that the dairy farmer would be keenly inter­ struments wiII be used as a reg­ farmers in their respective terri- ested in information which would ular feature in the educational tories and all will gather together help him in his business. So they development of the rural stu­ to . hear agricultural programs commenced giving it to him. dents of that state. Agricultural when the National Radio Farm Scores of letters poured in to Sam programs, prepared by the United School begins in October. Mr. Pickard, now Chief of Radio for States Department of Agricul­ Mathews and Mr. Arnoux have the U. S. Department of Agricul­ ture, will be one of the main fea­ experimented with the dramati- ture and then director of the tures stressed. zation of agricultural programs Kansas Station. A typicai letter Every school in the city of At­ and they have found that such a was received from K. C. Kough, lanta, Georgia, will be equipped feature is one of the most pop- . Scott City, Kansas, who said, this fall with radio sets and loud ular ever sent out from station "Your advice saved me the loss speakers will be placed in all the KTHS. of five milk cows. Two cows rooms. Special programs will be As a matter of fact, all of the died before I heard your lecture, given by the best talent of the agricultural radio programs sent but I saved the other five as a southeast, and included in those out from Washington, D. C., have result of your information." programs wiII be the dramatiza­ passed the stage of the conven- Imagine that-the one saving tion of interesting, important tional lecture-the material now would pay for a dozen radio sets! agricultural material. In the State of Arkansas is seen a development which will undoubtedly serve as a model to other agricultural sections in dis­ seminating information to our rural population. E. D. Math­ ews, Director of Vocational Edu­ cation, Little Rock, ArkanRas, is working in connection with G. C. Arnoux, announcer for station KTHS at Hot Springs, on the dramatization of agricultural programs sent out by the Depart­ ment of Agriculture. These two enthusiasts have worked out a system of rural adult schools and to date there are 112 of these schools organized in the state. Each teacher of vocational edu­ cation under Mr. Mathews' direc­ tion has been supplied with up­ to-date radio equipment; these Mrs. Sam Goodwinn, just east of West Point, Alabama, says she wouldn't take a gold guinea for her set, and attributes her success with poultry to the many fine point­ teachers will call together the ers heard over the air RADIO AGE for October, 1926 The jl/agazine of th e Hour 39

Twenty·five years ago this western Kansas farm of the Kuhrt family w as a barren plain. 190 1 m arked the purchase of cream separator and the turning from wheat to general farming. It was then that prosperity smiled on the Kuhrt ranch. T oday the most modern equipment of dairymen in Kansas and other states is the radio. This article t ells what the D epartment of A gricul- ture is trying to do f or American dairymen

When the Department of Agri­ milking. While milk will absorb F rom Illinois came the ques­ culture began its radio service, some silage taint from the air, by tion, "How much roughage should it took the tip from Kansas and far the greatest amount comes cows be fed 7" The Department instituted a national classroom thr ough the body of the cow; and r eplied "Feed all the roughage a for dairymen. Immediately thou­ cow will eat, including liberal sands of letters commenced pour­ quantities of some succulent feed ing in from these agriculturists li ke silage or root crops." in every section of the country, The vital interest shown by and those questions touched on American dairymen in radio a nd every possible phase of the dairy its benefits dl"Ove home to officials industry. A dairyman in Nebras­ of the Department that a n en­ ka asked, "I have bran corn and larged program was being de­ cob meal, and whole oats in my manded by the farmers them­ grain mixture to go with alfalfa selves. Consequently Mr. Pick­ and corn silage. Should I grind ard and his associates drew up a the oats also 7" The Department tentative program and submitted did not confine its answer to that it to broadcasting stations. Over one farmer, nor to a small group 100 station directors request ed of farmers, as would have to be this service, so beginning in Oc­ done by any other agency than tober the following dairy pro­ radio; the Department told the gram may be heard in every sec­ entire nation : "By all means tion of the United Stat es: Be­ grind the oats. You are losing a ginning October 8, and continu­ large part of the f eeding value ing for eight weeks: Dairy Herd by feeding it whole. This is true Selection and Improvement ; Pro­ of all whole grain feed for dairy A typical hill country farm house in the duction of Good Milk ; beginning Ozarks of Arkansas. F orty miles from a cows. Oats may be either ground railroad. the George Page family find December 3: F eeding of Dairy or crushed. Your grinder can, radio a great source of joy Cattle; a nd Marketing Dairy no doubt, be set to grind the oats Products on the Farm; beginning as well as the corn." it passes into the milk in an in­ Januar y 28: Dair y Buildings A Missouri dairyman wrote, credibly short time. By feeding and E quipment ; Problems in saying, "I have some complaint silage after milking, the sub­ Dairy Cattle Breeding; begin­ about silage flavor in milk. How stance causing the silage flavor ning March 25: Common Dis­ can it be prevented 7" and the and odor is thrown off f rom the eases of Dairy Cattle; Dairy Department replied, via radio, cow's body before the n ext milk­ Herd Management. " Feed silage immediately after, ing. Never feed moldy or de­ It is obvious that such an in­ instead of previous to or during cayed silage," clusive program will touch on 40 RADIO AGE for October. 1926 The Magazine of the Hour every question that is vital to the be replaced; radio must work in dairyman. All topics will not be cooperation with those men who of value to all farmers who are have close contacts with the farm­ interested in the dairy industry; but there is a potential helping ers. But radio has one outstand­ hand for every American dairy­ ing element which no other man contained in a million agency can hold before the farm­ farmer-owned radio sets. ers. It has made greater strides towards a position of a farm Farmers Like It necessity than has any other ECENTLY the Department R sent out a million enroll­ piece of machinery. educational ment cards, on which the courses force, or idea during the past in dairy. poultry. and livestock century. Unquestionably, the were outlined. Almost without radio will stay with the farmer. exception these cards are being returned with a number of the dairy courses checked. Thls is From your set with ample proof that farmers are awake to the value of radio in ~\l-rns, their daily schedule. LOUD SPEAKER r could cite many specific cases Volume with Perfect Tone which vividly tell of the benefits Vlhy sacrifice the excellent work secured by farmers from the of the set by using an inferior radio farm programs. r believe speaker? A BURNS will reproduce that one more, however, will ade­ with pleasing exactness every t one and sound that the set can pick up. quately picture the type of work At your dealers or direct. the Department is undertaking. A farmer in Alabama wrote to the Department, boasting that he STATE AND 64TH STREETS Shielded Six CHICAGO, U. S. A. was making a good profit from a Ask about Burns "B" Eliminator group of scrub dairy cows. The T~~g;e~~elt~e:esS::r ~r~~~c~:t tr~~ county agent was instructed to ceivers. It embodies complete shielding of all radio frequency The Biggest investigate the situation in order and detector circuits. The quality . that the complete records would of reproduction is real-true to the In be on file, and the county agent ear. Dollar' s Worth Behind the Shielded Six is compe­ found that the farmer was ac­ tent engineering. Day in and day RADIO tually losing money on those out it will get distance-on the speaker. Local stations in the most scrub cows but was making crowded area separate completely fairly good returns by dragging -yet there are but two dials to county roads in his neighborhood. tune. These features----its all metal 514 PAGES chassis and panel. its ease of assem­ Compiltd II, The farmer was induced to com­ bly and many others. put it in the HARRY F. DART, mence replacing his scrub cows small class of ultra-fine factory­ E.E. with pure-bred stock in order built < sets, priced at several times Forttltrly ",ilb tb. the Six's cost. WotlhrD Ell!ctric Cu .• that his business could be put on The S·M 630 Shielded Six Kit-including aIId U. S. Army lu­ all sp«"ified matched and measured parts a money-making basis; at the -price $95.00. Itractor of Radio. Th~ 633 Shielded Six Essential Kit contains Tl!chuiea.rr,. I!ditl!d \, same time he was advised to take four condensers, four radio frequency F. H. DOIDI transformers, four coil sockets, four stage the radio course in Dairy Herd shields and the link motion-aU factory matched-price $45.00. Management in order that he Clear and complete instructions, prepared could tell accurately how his by S·M engineers, go with each kit-or N '1o~g~t n~~ !~~t~: ::aO:::. ~~9 ~I ~:: will be mailed !leparately for SOc. in 514 pages crammed full of ev ~ry possible radio detail. Written in plain language, by engineers business stood at all times. I 635 SHORT WAVE KIT for laymen. More than 100,000 sold. The radio service works in Contains the carefully designed and IT EXPLAINS: Electrical terms matched essentials for a real and circuits, antennas. batteries, close connection with the county short wave set. Its range is 18 generators and motors. electron to 150 meters. The kit contains (vacuum) tubes. many recei.vi.ng agents who are stationed in all hook-ups. radio and audio frf!Quf!ncy of the forty-eight states. Certain 4 plug-in coils, 1 coil socket, 1 amplification. broadcast and com­ I coupling condenser and two 140 mercial transmittf!rs and rf!cf!ivf!rs, information that is given by mmf. condensers----all carefully de­ euper-regeneration, codes, etc. signed for operation together. With SOld $1 todeJ1 and gtt thi. 514.pag" I. C. S. Radio radio must be followed up by in­ Handbook-thO! bi,gtd 1I011lO! ill radio toda,. the four coils, the amateur bands tensive demonstration on the part I fall well to the center of the tuning r -- :t;n:;i~:I-r.: e-;o:-de:eil-S:o: - -. of the agents, and in many cases scale-and" dead spots" are totally I BOll B784.E. Str3. ntan. Penna. I the county agents send in perti­ eliminated. The antenna condenser I ~ &l~~~1:'e ~~~ .£.~~ari. J.'l e~.He n:~~~ W!;;d=~~ J allows coupling adjustment to suit I It I!I underBtood that it I am not entirely sath· I nent questions which farmers in individual conditions. Price $23.00. I ~~ ~/lt~e{~~~rnUl~h1~ o':::. within five days and f their respective territories desire I : N'm...... : SILVER-MARSHALL, INC. to have answered. The work of 850 W. Jackson Blvd. I i~~%88,;;;:~·d·~~d-~~~iO!ii··s i ·: 5·0··iFj,o u ··.;.;l~i · iil~ I the county agent is, of course, Chicago, U. S. A. L __ ! :::.r:. e:/:,,::,o:d~n '::~h:O~ __ ~ extremely important and cannot iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii~ Please mention Radio Age when writing to advertiser8 RADIO AGE for October, 1926 The Magazine of the Hour 41 Pick#fllu.ps _~ (s.~ and _I(HJ-\_I d fo, ..~","- H 00k #fIIUpS \,.O$_~ ~~r~~~~~~~ Conducted by F. A. Hill T~n~~~~e~ b~~~~~!d,;~er I~i~ ;i~~p:;;:e~~9Whe~~~~ie~j:rs~:h~~~e~;~~no~~;;f~s~~~i~: and the construction and operation thereof. Many times our readers disagree on 'technical points, and it should. be understood that RADIO AGE is not Tesponsible for the views presented herein by contributors, but publishes the letten ana drawings merely as a means of permitting the fans to know what the other fellow is doioa: and thinking,

HORT wave receivers have NE of our old readers who upon the amount of traffic to be Sbeen used for many pur­ O has been twisting dials for handled and the weather condi­ poses other than reception, some time all over the world, W. tions on the Atlantic lanes. but it remained for H. F. Bloom, H. Shorter, writes telling us he 18 Chestnut St., Stoneham, is returning to England to locate Mass., to catalog another useful at 39 Walton Road, East Molesey, USING his L-2 Ultradyne, occupation for the short wave Surrey, England. After having George S. Everhart, P. O. set. He built one from the April been on this side of the globe for Box 105, Macatawa, Mich., sends issue of RADIO AGE, logged all the some time we believe our DT's in a list of 101 stations logged U. S. districts and a Frenchman. will be curious to know what luck since June 21 of this year. He Then he found he could hear the he has in picking up the Amer­ has such good reception condi­ neighbor's telephone conversa­ ican sta tions from abroad tions there he brings in WJZ, tions by listening on his own set. throughout the year. KDKA and WCCO without an­ He has not told us any of the DX tenna, loop or ground, and gets he got from the neighbor's phone them on the loudspeaker, too! ROADCAST listeners who Sure, you rate a DT button! but we will award him the DT B desire to get good code prac­ button anyway. tice should tune in WIZ on 43.02 meters who seems to work 24 ROADCASTING station call N this page is shown the hours a day, except Sunday night. B letters with something sig­ O transmitter, receiver and in­ This station, belonging to the nificant or distinctive attached side of the radio shack of Station Radio Corporation and handling thereto, have become more of an 7AIB, owned by Herman F. Hel­ trans-Atlantic traffic, generally obsession than we ever expected. gesen, at Port Angeles, Washing­ uses a tape transmitter. The Witness the latest change in the ton, one of the many stations matter is therefore very clean cut call letters of the Atlantic Auto­ with whom 9BHX has main­ and easily readable. The speed mobile Co.'s station KFLZ, at t a i ned communication. The is anything from 18 to 40 or more Anita, Iowa, now broadcasting transmitter uses a DeForest H words per minute, depending under the call KICK. Tie that! tube; with Hartley circuit; plate supply 1100 volts rectified by 24 jar chemical rectifier with the old reliable borax solution. Antenna current of a half ampere is se­ cured, using the third harmonic of the antenna system. The transmitter panel at the right has all parts mounted behind, with the electrolytic rectifier beneath the table. The receiver, left, is a Reinartz with a single stage of amplification. The antenna is 93 feet long, one wire, 33 feet high at one end and 53 feet at the other. The counterpoise is 90 feet long, single wire, and is 9 feet above the ground. Helgesen uses a breakin system by means of a 90 foot single wire at right angles to the transmitting an­ tenna, and reports good results thereby in handling traffic. 42 RADIO AGE for October, 1926 The Magazine of tlze Hour NE of our recent visitm's at O the RADIO AGE laboratory was C. J. Bolger, 822 West 6th 9BHX St., Topeka, Kans., who is very much interested in the conversion TRANSMISSION of a low power transmitter to crystal control. While there, Mr. During the month of Bolger had a chance to examine August 9BHX (42.21 and the transmitter described in this issue's bl ueprint section and feels 40.52 crystal control) re­ he will shortly have one of his ports communication with own in Topeka. the following stations: WO pictures of Station 6BXC, T belonging to Harold H. Day, WVZ 6BXC 1661 Grover St., Los Angeles, 8HR 2ASQ Calif., are shown on page 42. In the lower one Mr. Day himself is 3EE 2AQW shown at the key, while the upper 4BY picture shows the transmitter 9MO on the right. This is another of 4AV SPH the American amateur stations ----"-- that is filling the air with a good signal, having worked Zedders and Frenchies as cards on the wall show.

HOSE who can seldom see any T difference in the amount of static on the different wave bands used in radio should fix up their receiver a la plug in and make a rapid comparison between the 40, 80, 120, 250 and 550 meter bands. One night particularly we noted Dubilier Condenser Type 907 , static terrific on 80 meters and Capacities 0.1 to 2.0 mids. Price $0.60 to $1.75 I yet on 40 you could hardly notice it. The same night static on the "By-Pass" was the name original­ ly given to small paper condensers by 250-550 meter bands was very DubiIier. This name described their slight. While this pattern does functions- such asshunting radio fre­ not always hold true nevertheless q uency currents around high resistan­ it is interesting during the eve­ ces, and their use in amplifier circuits. ning to go up and down the band But now the clumsy old" By-Pass" condenser is out of date. The high to see which channel carries the voltages used in radio today along heaviest load of static. with sub-panel construction, de­ mand a condenser of higher electrical efficiency and more compact size. In the new Type 907, Dubilier has made a compact alI-purpose condenser with a working voltBge* of 160 volts D. C. With improved soldering lug terminals and mounting feet, Type 907 will give more efficient service in smaller space for every purpose for which the old" By-Pass" type of condenser has been used. For long life at high voltages insist on Dubilier Paper Condensers. Dubilier

* Working voltage means more Ili all ulesl voltage." It is the voltage al which a condenser may be safely used in continuous ~

Please mention Radio Aye when writinu to advertisers RADIO AGEfor October, 1926 43

Wonderful offer direct from the factory! The world's greatest radio. Completely Assembled A.p ~r fect working, single dial control, 7 tube receiver. And just to prove our claims, we will Big Discounts ship It to your bom~ for )0 da~st free trial. Test it under an conditions. Test it for distance. vol­ ume and tonal quahty - and If you are not co nvinced that it is the best single dial set you ever to Agentsand Dealers heard. relmo it to the factory. We don't want your money unless you are completely satisfied. !IUl.mll.IIIII.I:III.IIU1.IWI. nIIIIlUlU. IIIU.III I1.IIIIIIIUlUIIII III.11111 .1 i Ble PROFITS § Metrodyne Super-Seven Radio i TO AGENTS AND DEALERS !II ~ Our Agents and Dealers make big money I!!! A single dial control, 7 tube, tuned Easiest set to operate. Only one small ! selling Metrodyne Sets. You can work all == radio frequency set. Approved by knob tunes in all stations. The dial is electric­ II or part time. Demonstrate the superiority ! America's leading radio engineers. Designed ally lighted so that you can log stations in the ~ of Metrodynes right in your home. Metro- ! and built by radio experts. Only the highest dark. The volume control regulates the recep· ! dyne Radios have no competition. Lowest - Quality low loss parts are used. Magnificent, lion from a faint whisper to thunderous volume, 1,000 to 3,000 miles on loud speaker! The ).Iet­ i wholesale prices. Demonstrating set on 30 = two-tone walnut cabinet. Artistically gilded § days' free trial. Greatest money-making !I!!I! rodyne Super-Seven is a beautiful and efficient genuine Bakelite panel, nickeled piano ! opportunity. Send coupon .b.elow-or a let- receiver, and we are so sure that you will be = hinge and cover support . All exposed metal delighted with it. that we make this liberal !.:~~"iillI:~I~~I;~~~7n:I~h~;,[r~I:~I~. mll. : II I1 .l ru l. m ll; parts are beautifully finished in 24-k gold. 30 days' free trial olfer. You to be the judge. Mail COUPON Below! Let us send you proof of Metrodyne quality F. L. WarnOCk , Greentown, Ind., writes: "1 r~eived the Met- ~~li~~i~,~~ ~~e aa::~y~.rp more than pleased with it. Got C. ites: "Received my :\!etro­ t these one-dlal set.!! o trouble in tuning you will please send

'e efer scen. We will send you hundreds of similar letters from own­ ers who accla im the Metrodyne as the g reatest radio set in the world. A postal, letter or the coupon brings Metrodyne Super-Six complete information, testimonials, wholesale prices, Another triumph in radio. Here's the new 1927 model Metro­ a nd our liber.ni 30 days' free trial Oiler. dyne 6 tube long: distance tuned radio frequency receiving set. Ap­ ~ ...... •.•..••.••...... proved by leading radio engineers of America. Highest grade low loss parts, completely assembled in a beautiful wa lnut cabinet. METRO ELECTRIC COMPANY Easy to operate. Dials easily logged. Tune in your favorite station za6>1·71 N. California A .... e., Dept,. :1:17 instantly on same dial readings every time. No guessing. Chicago. IIUnois lfr. Howard. of ChIcago, said: "While fi'l'e Ohie!l.ll'o broadcasting statiOnB Gentlemen: were on lhe aIr I tWled in seventeen ollt-of-town stations, incllldinl:' New Send me. fu ll particulars ahout l'Ietrodyne 6 tube r~:!lI gn4e~a~e~:~YIC~; 'h~~a:l.,}OUd spea~er horn. very loud and dear, as MAlLl:J~ON ~ and 7 hlbe sets and your ]0 days' free trial oller or send a postal or letter.Get our We are. one the pioneers of radio. The success of Metro­ proposition before buYIng a radio, Name______oE DBaI direct with manufaeturer- dyne sets is due to our liberal 30 days' free trial o£le.r, Sa .... e Money. which gives you the -opportunity of trying before buying. Address_. ______METRO ELECTRIC COMPANY Z161·71 N. California Ave•• Dept. 117' Cblcago, Illinois 44 RADIO AGE for October, 1926 The Magaziile of the Hour

Upright Resistor New West Coast Burns Speaker Units Mounting Issued Sales Company NEW man u f act u l' e l' s' A agency, the Western States Sales Company, Inc., has recently been formed for the purpose of actively and completely repre­ senting manufacturers on the Pacific Coast whose sales in this territory have heretofore not NTERNATIONAL Resistance been fully realized. o produce a speaker unit which I Company's new type upright The members of the new or­ T is capable of reaching the full resister mounting base illus­ ganization are: B. R. Hassler, range of the musical scale with the trated above will perhaps be president; George J. Lane, vice­ utmost clarity and trueness has of interest to readers of RADIO president, and E. W. Kennard, been the aim of all speaker manu­ AGE. secretary and treasurer. Mr. facturers. It has been the good This unit is made of very Hassler was for the past three fortune of the American Electric high test insulation moulding years .general sales manager of Company of Chicago to develop and is designed to accommodate the Colin B. Kennedy Corpora­ such an instl'Ument in their Burns the standard size fixed and grid tion, St. Louis, and for two years Hi-Lo models shown above. resisfor as well as to accommo­ prior to that time was in charge date a standard type of grid of the Kennedy Corporation's condenser. Pacific Coast sales. Radio Shows It is thought that an upright Headquarters of the Western mounting of this type would be Sales Company, Inc., are at 1632 Following are some of the of advantage to manufacturers South Los Angeles Street, Los radio shows being held during the and set builders in the conser­ Angeles, California, with district Fall of 1926 season: vation of space in assembly. sales offices in San Francisco and Los Angeles, Calif., Fourth Seattle. annual Radio Exposition, Ambas­ sador Auditorium, September 3 Radio Industry Does Not Care to 11, inclusive. High Current Resistor for Czar New York, N. Y., Third an­ nual Radio Show, Madison ADIO manufacturers through Square Garden, September 13 to R their association gave a def­ 18, inclusive. inite "No" to the proposal that a Q~ czar be appointed for the radio Resistors shown above, made Cleveland, Ohio, Second annual industry at a meeting recently by the Tobe Deutschmann Co., Radio Exposition, Municipal Au­ held. are especially designed for op­ ditorium, September 20 to 26, in­ A. T. Haugh, president of the eration with changeless charac­ clusive. association characterized recent teristics, capable of carrying a Chicago, Ill., Allied Radio Con­ published reports of chaos in larger current for B eliminators gress, Hotel Sherman, September broadcasting as the work of pub­ where resistances are required 27 to October 2, inclusive. licity seekers and expressed the through which the plates of sev­ opinion that the situation is well eral tubes will be supplied. Columbus, Ohio, Third annual Radio Show, Memorial Hall, in hand. In the Tobe veritas Hi-Cur­ September 28 to October 2, in­ The board voted disapproval of rent Resistor, designed and pro­ clusive. international Radio Week. The tected by patent applications of association, it was explained, will S. B. Allen, the resisting mater­ Youngstown, Ohio, First an­ no longer sponsor or support the ial is directly on the inside of nual Radio Show, September 30 overseas radio tests, because of the outer glass tube, and per­ to October 2, inclusive. poor results. manently united with it. Chicago, Ill., Fifth Annual RADIO AGE for October, 1926 The Magazine of tlze Hour 45 Radio Show, Coliseum, October Building 9-Tube Super Brings 11 to 17, inclusive. Back Faith in This Receiver Indianapolis, Ind., Second an­ (Continued from page 10) nual Radio Exposition, State volume knob up to the point Fair grounds, October 25 to 30, where the panel voltmeter reads inclusive. between 31h and 4 volts, then Detroit, Mich., Annual Radio rotate the oscillator dial (right) Show, October 25 to 31, inclusive. over its scale. As you increase capacity on the oscillator con­ denser you will begin picking up How Many Laughs Per stations; hold a given setting on Meter to Be Decided the oscillator, and turn the loop OW many laughs to the dial to position where signal From _H _ wave-length is a poser to strength is at a maximum. If Atlantic to Pacific be determined in a microphone further volume is required turn From experiment conducted by Stanley up volume control and turn out Canada to South America Hall over KOA, Denver. resistance in the mod ulator Can the voice, unaided by acro­ knob. batic antics, in itself produce In tests at the laboratory us­ streams of chuckles and side­ ing the loop and loudspeaker aching laughs? made by the Duro Metal Prod­ How much of the tickling of ucts Co., on other than a Mon­ the resibilities of an audience is day night, the results were ex­ due to facial expresson in telling ceptionally good. Local stations a funny story? Is it possible were sidetracked at will and dis­ that facial unmuscling can be tance considered excellent for TRANSFORMERS brought into the voice so that the August secured. As a matter of I Have Made Finer Radio laugh will come 100 per cent? fact the operation of this set has Reception Possible Broadcast listeners are asked to brought back some of the good decide. opinion of supers which we had HERE is no interference from Formerly of the Keith and Or­ lost through the deluge of tuned L!:.JTIpowerful local broadcasting sta­ pheum circuits, and known from radio frequency sets. tions possible 'with these units. They can be used under the coast to coast as "the man of a We will be glad to receive million stories," Mr. Hall is comments from our readers on !~de~~e~ ~tilIP;flf~~~~:t::l~c~ tion of broadcast concerts at chalked up for a thirty minute this super and if the interest choice. novelty program, "Wit and Hu­ shown warrants, further super mor of the Age," every Tuesday material will be printed. ITI~ E~~tho~~~iteh}~I~~~~l~su~li~; evening at 8 :30. not obtainable with other trans­ His program is a cross section formers. of wise-cracks, thrusting merrily Be sure to get the N ovem­ ITIHEY amplify the weakest sig­ at everything from evolution to ber number-Full of ,Excellent _ nals to the utmost loudspeaker flappers and from Irishmen to the Hookup Articles. volume. Einstein theory, it is said. I -rl~~~n i~e ~~o~dce:s~e~~nd{ti~~~~

ITI~~~ ;j~r~tf~b~~.with all types rr l~~i~al a:eet _ ba~ld~~a!ou\~e d:g!~ - unsurpassed for quality, clarity and volume.

No. H.210 Transformers .. __ :.$8.00 No. H .21S Transformer ______8.00 No. F.320 Transformer. _____ 8.00 No. L.425 R.F. Choke ______5.50 No. L.430 R.F. Transformer 5.50

Rernernbe1' The NalTle H. F. L. Insist On H. F. L. Units HIGH FREQUENCY LABORATORIES 133 N. Wells Street Above is shown-the Model 5 receiver made by the Apex Electric Co., Chicago, 111. Chicago Illinois It is a five-tube set, transformer coupling, single control with illuminated dial. It is but one of the many Apex models which will be seen at the Chicago Radio Show. Ptease mention Radio Age when writing to advertisers 46 RADIO AGE for October, 1926 The Magazine of the Hour See and Hear Wavelength With their form as described, will re­ Quartz Crystal Tube spond, if excited by a voltage as low as 30 volts, but only in case (Please turn to page 8) the exciting voltage is within and glass vessel are unimpaired. the limits of 0.1 per mille iden­ frequency and wavelength of tical with the resonance fre­ the transmitter to which it is ad­ quency of the quartz. justed. "Although the freqency "On account of the low ten­ may be easily calculated from sion required, the strain im­ the given wavelength," points posed upon the quartz-body is out Professor Giebe, "there will reduced to a minimum and the be some uncertainty in this cal­ life-time of these resonators is, culation on account of the uncer­ therefore, unlimited. In case of tainty in respect of the exact higher voltages the cell will also velocity of light. For this rea­ become luminescent; this lumi­ son, the exact frequency is stat­ nescence, however, is solely due ed, which is independent from to a glimmering discharge be­ Precision! the velocity of light. These tween the electrodes. By means quartz resonators, therefore, Scientific precision of a high order of an interposed oscillatory cir­ may be better designed as 'fre­ cuit, which is approximately enters into the manufacture of quency standards'. By means the Durham ~[etallized Resistor. tuned for the proper wave, it is Noiseless and guaranteed to main­ of indirect methods capacities easy to tune a transmitting sta­ tain the resistance marked on its and self-inductions may be tion exactly to the prescribed label. measured quite exactly by wavelength. First, the coupling means of these quartz-resonat­ 10 meg. to 500 ohms, from SOc to SI.OO is made somewhat more close ors." and any preliminary tuning is Plurality of Devices made by means of the glimmer- ing effect. If now the coupling DtiRt}AM F A TRANSMITTING sta- is made looser, the luminescence RESISTORS I tion desires to operate over a proper of the quartz will be ob­ INTERNATIONAL RESISTANCE CO. slightly variable range of wave- tained, which takes place only Dept. C, Perry Bldg. Philadelphia. Pat lengths, a number of resonators in case the tuning is accurate are used. In this plurality of within a frequency limit less devices, the resonance of each is than 1 per mille." only slightly at variance. For ,______example, there may be an ar­ ."...... rI' ...... :: rangement of five resonators, adjacent to each other. The (:='D~:: ~ .. middle resonator is tuned exact­ ~ > ly to the desired wavelength, :: THE PERFECT GRID LEAK -: while the two resonators on the :: Provides a noiseless range :: •• of grid leak resistance from .. left and the two on the right of •• U to 10 megohms. Assures ;: the middle resonator are tuned :- most effective grid .. just a fraction higher and low­ • : leak resistance •• er, respectively, of the latter. ~ S~~;lf;~~!~~~ ~ Fora limited time only. genuine The sensitive gas-filled lamp is .: ser(O.00025)issep- .: World Storage Batteries can be .. arate. Metal parts :: gotten at actual cost. Every.t placed above these resonators, I cent of profit has been cut out I 2-Year :: nickel plated. One > in order to keep our full factory Guarantee it serving a threefold purpose­ ~ hole mounting. • organization busy during the Bond slack season. Prices below are in Writing indicates how to tune the trans­ lowest in history. ApProved mitter; protects the resonators ~ 6lJen-BmrJJsy Co. ~ World Batteriesarenationally and U$led al •• Electric ControUine Appararo. :: known for dependable, klllg Slcmdmd against excessive current; and 289 Greenneld Avenue Milwaukee. Wi'... wearing-performance. Solid hy Leading ~ .. Rubber Case prevents acid .f/ulhoTitie3 the luminous effect tells when .;,-••••••rI' ...... and leakage. Send No Money! the transmitter is operating pre­ Juat will cisely on the desired wave length. "Since it is practically impos­ sible to ascertain any influence due to variations of tempera­ ture," state the inventors in ex­ JU>L hOl olt lhs IJr ~s~ - lD27 Il~diu Catal

AERO TUNED RADIO FREQUENCY KIT-PRICE $12.~ R eplace your present in ductance with this Aero Coil Tuned R adio Frequen cy Kit. It will p03itiveiy improve the performa nce of your receiver. Special paten ted Aero Coil construction dim_in ate;; radio frequency .losses. Y ou will notice insta ntly, a tremendous improvement in volume. tone and selectiv ity. This kit con sists of t hree matched units. The antenna coupler has a variable pri­ mlry. Uses .00035 condenser. Coils are uniformly air spaced. No dope is u sed. Conseque ntly they tune into resonance on a "knife's edge." Eight page colored blue print, actual size layout book, and complete instructions for building the super-sensi­ FREE with Each Kit tive 5-tube AERO-DYNE RECEIVER. (Extra copies, 75c each.)

This is the supe r-sensitive set that has caused such a sensation because of its remarkable per­ formance and extreme selectivity under t he most adverse conditions. Tunes extre mely sharp. Brings in fa r distant stations through h eaviest local broadcasting. Remarkable in tone. All in a ll, probably the most e fficient 5-tube set t hus far perfected. You should build it. It's easy with the in structions we furnish. Aero Short Wave Kit Aero Interchangeable Coils Aero 3 No.4 and 5 \ '" Circuit

< ' ~" Tuner ,I "':" The true low- ', .. _ !I' loss tuner: Vari- . .Ji able p nmary, ... . 'IT. . h ~:~ss~~:m35 con- Price __ $6.50 Stock No. LWT-12S Stock No. Completely Interchangeab1., CT-80 Adopted by experts and amateurs. Range 15 t o Stock No. 130 meters. Complet ely interchangeable. In­ INT-4 A genuine low­ cludes 3 coils and base mounting, covering U. S. loss a nt e n n a bands 20, 40 and 80 met ers. Uses .00014 con­ Increase ra nge of your short wave tuner by secur­ coupler, with vari­ denser on secondary, and .00025 on feedback ing coil No.4 and coil No.5 , combined range control. 125 to 550 meters. Roth interchangeable coils able primary. Price__ ...... _...... __ $12.50 fit the same Aero base supplied with the short Uses .00035 con­ wave kit, a nd uses the same condensers. denser Aero R. F. Regenerative Kit Coil No. 4- range 125 to 250 Price _._ $4.50 meters_ __ $4.00 Stock No. AX-45 Coil No. 5 --· range 235 to 550 Aero Crystal Coil or Wave meters_ . . 4.00 Trap Unit

Aero Osciilator Very effective be­ cause of its ideal Greatly improves the Aero Coil char­ performance of the os­ d ilator circuit of super­ acteristics. Also fo r het erodynes, u;;es .0005 crystal sets. Uses One Radio Frequency Coil and one tapped. 3- conden& r. .00035 condenser. circuit tuner. Makes the world's m ost dnClent 4·tube set; uses .00035 condenser. Price_ ...... $5.50 Price .. .__ $4.00 Price__ $10.00 Stock No. OS-SS Stock No. WT -40

Order these coils from your dealer today AERO PRODUCTS, INC. Dept. 106, 1772 Wils0t:l Ave. Chicago, Illinois Pacific Coast Representatives: Henger-Seltzer, 1111 Wall St., Los Angeles; 377 Brannan St., San Francisco

Please mention Radio Age when writing to advertisers 48 RADIO AGEfor October, 1926 The kfagazine of the Hour VVhat Type of Loud Speaker I Should I Use? Heavy-Duty (Continued from page 19) covered by these instruments. If there seems to be any tendency RADIOHM to blasting or rattle, it is well to hear a saxophone or cornet solo, or a soprano singer. If muffling of tone is present, the speaking voice offers the best chance of comparison.) Since the lower tones are present to a certain degree while we are using the No. 4H repro­ ducer, we may assume that the )Dr reproduction of music by this set is fairly even over the entire mu­ Simple Control sical scale, therefore we take for of B -Battery the next choice speaker No. 2C, whose tonal reproduction curve, Elitninator as we have seen, is approximately a straight line. Upon connecting ~T full efficiency from your G "B" Battery Eliminator by it to the set, however, we find the installing a Centralab Heavy­ resulting tone to be somewhat Duty Radiohm: Full resistance unpleasant-what might be called variation with a single turn of . "rough" or "fuzzy"-although knob, allowing panel marking the low tones are now brought for proper setting to provide various voltages, Tested and lHORDARSON . out in their true values: approved by the Raytheon What we need, then, is a repro­ Labora tories. Power Amplification ducer giving practically straight Resistance remains perma­ and line response in connection with nent as adjusted (no carhon B-Supply a mellow tone. Checking over particles or discs), and remains same for any knob setting re­ From the A. C. Line our characteristics, we find that loud speaker No. 5H should "fill gardless of how often adjusted. Force a car up a steep hill and the bill," and, sure enough, a trial Bushing and shaft insulated to the engine knocks. Force a withstand 1500 volts. Its radio set and the quality be­ proves it to be all that could be smooth and noiseless operation comes ragged and the reproduc­ desired. will greatly improve your set. tion distorted. As a final word, it should again Faithful reproduction of the $2 at your dealer's or deeper bass tones requires a be stated that all mental judg­ mailed direct onreceipt considerable expenditure of elec­ ments of loud talker and receiver of price. triali energY,-more, in fact, than the vacuum tube of the compatibility must be backed up average receiver can handle. with audible proof if the very Central Radio Laboratories A power amplifier built with best results are to be obtained. 24 K eefe Ave., Milwaukee, Wia. Thordarson transformers and The value of being able to form a Makers of a full line of variable re­ chokes uses larger capacity sistances for 69 manufacturers of tubes and reproduces the h eav­ mental judgment is that one is Iea.ding standard sets. ier, more vibrant tones with enabled to come more directly to undistorted quality and volume. Operates from the light the selection of the proper circuit B-supply for speaker, and is consequently less entire receiver. No con­ liable to be satisfied with a com­ m;1tIDRljJ, trols. Requires no ad­ justm ent. Uses larger bination of set and speaker that capacity tubes. is not wholly satisfactory)n the 6-Volt TRANSFORMER R-198 sup­ belief that-"radio can't be ex­ pli es 25 V. plate and 7 1-2 V. Storage filament for UX 210 tube. pected to give perfect results, Price $12.00 anyway." That so many people Radio"A" 30 HENRY CHOKE R-1 96. are satisfied with such a weak ex­ Battery 70. M. A. capacity for filter cir- cuse is deplorable, and is many cuits. .'Ie", ~ln. Price $5.00 times responsible for the condi­ r~:f:g $5.00 = tion we often find of musically '~k~! c. o. D. Thordarson Electric ual- SeDdNo sensiti ve people becoming dis­ with MODey Mfg, Co, gusted with radio. These same Solid Rubber Case 500W. HuronSI __ Chicago, IU_ people would all become enthu­ an BS8oraoee against acid and leakllg:e, Qrdw NO'W. W,e siastic fans if they only had the ~~WI>~~e:;r9;i~~~:O.ir~;:OG~~~~i~; ~t~~iI8T0j Trans/O,.merSpecia/ists SinC!e18'J5 opportunity to hear really eu­ WORLD BAtTERY CO. WORLD'S OLDEST AND LARGEST Wo rl d Dcpt.136 , EXCLUSIVE TRANSFORMER MAKERS phonius reproducer and receiver STORAGE BATTERI ES 1219S.W.buhA .....Chlc ... combinations. !KORli"7Wf.f.7W6N'WiS-;.-WU ,KGQ.o!:8Fg ...... WJy.KmI Please mention Radio Age when writing to advertisers RADIO AGE for October, 1926 The Magazine of the Hour 49

GJbis 84 Page Wonder· Bookof RADIO Bargains

Send for this guide to Radio prices and Radio quality. All of our vast resources and radio experience have been utilized to assemble for you in one gigan­ tic institution, tbe best and newest things in radio. Tbe Randolph catalog is indeed the radio market place of the world - a masterpiece of mercbandising that befits our bouse-the largest exclusive radio mail order house in the What Our Catalog Contains Over 2,000 items-from the most beautiful, fully equipped console model radio set, down to the smallest part or tool for the set builder-kits, parts, and supplies of every conceivable type and style. All beautifully illustrated and interestingly described. And to give this book added value, we have included radio data that makes it an invaluable text 9P1gr')fe SayeYouNoney book for every lover of loday's most fascinating and most wonderfu1 achievement-RADIO. Radio Sets Radio Parts and Because we handle radio exclusively In this great radio market place you will and sell a tremendous volume of find table model sets and console types with Supplies everything in Radio, we can concen­ bui'lt-in loud speakers; the newest ampliphonic The Randolph catalog also contains a most trate our buying power for the ben­ console sets; new Spanish period consoles; five, complete line of "B" Battery Eliminators. ln~ Six, seven. and eight tube sets. with three dial, cludine: the famous Raytheon Eliminators; the efit of our customers. two dial, and the newest and most popular sin­ latest type of Loud Speake rs, Cone Speakers, a Volume purchases regulate prices. .. Ie simplified wonderflll de.-ice mean" better recePtion, tion is limited to specified fre­ Sha rper tuning. End$ that annoying h'Um. More Chief of which has recently re­ rea l pleasure f rom yo'Ur ~et. quencies. Some foreign govern­ COMPLETELY EQUIPPED- ported that the use of spark NO '·EXTRAS" TO BUY Operates perfectly on direct Or alternating current. ments have opened new and pow­ Simple directioru. enclosed_oyone can plug it in transmitters has been reduced to to any 'kind of set up to sU: tubes. Conatant volt­ erful spark stations for marine age I!:kes set more power without d"nger of burn· emergencies only and that the i ng out tube... communication, and even for Costs no more than ~et of good "B" bat­ ships are using only the frequen­ teries. SoUdly builtin be.o.utifully fini~hed point to point communication metal ca.~e. cies permitted them by the rec­ SEND YOUR ORDER NOWI where wires or cables are avail­ DOII't blame your set beeau ~e rUn down ommendations of the Fourth Na­ "a" Batteries "'oo't let it work right. able. Little or nothing has been Order your Eliminator NOW. Former tional Radio Conference. price SI2.95. Now cut to $ ;.95. \Vrite name and addrClO-~ 00 a piece of paper, pin a doUar bill to it. done in most foreign countries to lind mail it TODAY. Pay postman balance ($6.95 IlI'Us a few cenf.$ postage) when he delivers your HE navy has vigorously reduce harmonics and other in­ Eliminator. U ~e it ten d .. y~. If not more thaD T sati3fied, return it and get your money back, pushed technical research terfering emissions from radio­ THE ROLL-O RADIO CO. and development for the improve­ telegraphic stations which were 0 .. pt.8, ment of the radio situation and already in service when radio­ Third and Syc:nrnore St•. , Cincinnati, Ohio its efforts have been crowned broadcasting began. with' an appreciable degree of In the United States, on the .. ~ 'r~~tD~~:l~~~r .~. success. It was the first service other hand, not only has the gov­ , , A three-foot cone to follow the amateurs in the ernment avoided restriction on speaker-unit deve1· development of high frequency broadcasting as far as possible, oped by the inventor (short wave) communication on but it has cleared a wide band of of the Tropadyne. Ea­ sily assembled, saving a practical traffic-handling basis, frequencies for exclusive use of 80 % of the cost. reducing necessity for use of the new service and has actively Complete Kit with blue prints sold on higher frequencies which cause aided it by removing its own sta­ rigid money-back disturbance to broadcast recep­ tions from this band and by re­ guarantee - shipped tion. It has devised and applied quiring the removal of other , prepaid or C. O. D.­ _!i( $10.00 new methods of stabilizing fre­ radiotelegra phic stations from ENGINEERS' SERVICE COMPANY quency adjustment, of eliminat­ this band. The navy has commis­ 25 Church St. New York, N. Y. ing extraneous emissions and of sioned no new spark stations suppressing harmonics. It has since the advent of broadcasting reduced interference to other nor has it purchased or manufac­ services by reducing the time on tured any spark or arc apparatus RADIO ~~ ~~~~_t~it~i~a; the air to clear messages, through since that time. radio dealers operating live-wire development of improved meth­ The navy is today maintaining stores who want to make the best ods of operafion and the develop­ a world wide radio service of con­ jobber connection in America. ment of competition among oper­ stantly increasing efficiency, op­ DEALERS Our eight big vvarehouses furnish you ators. erating about 150 transmitters in vvith the finest products in radio, And The Navy Department has con­ about 100 stations on shore and we ship fast. sistently loaned a sympathetic some 900 transmitters in more WANTED Write today on your letterhead for big ear to the pleas of the broadcast than 300 vessels at sea. It is con­ catalog of nationally advertised lines. listener and has championed his stantly effecting improvements Ask for L 1006 cause where possible. All com­ as regards disturbances created WAKEM & McLAUGHLIN, Inc. plaints received from broadcast to broadcast reception, and 225 E. ILLINOIS STREET, CHICAGO, ILL listeners have been sympathetic­ stands ready at any time to do ally received, appropriate action all within its power to aid the has been taken thereon, and in radio broadcast listener, and to AKE MONEY EVENINGS Let me show you how 4364 men, without ex· countless cases naval personnel further the development of what Mperience add $25 to $75 weekly to their in. come without giving up their present position.. has gi ven direct assistance to it believes to be the world's finest B.Z FISCHER,l22 W.Auilotin AVCl •• ChlcMO. ~ Please mention Radio Age when writing to advertisers RADIO AGEfor October, 1926 The }(Iagazine of tlze Hour 51 RADIO FOG SIGNALS

for B.Eliminators

ADIO to the front again. R This time in conjunction Bradleyohm·E is a new with the very familiar farm and enlarged Bradley· lighting plant, to perform an in­ ohm designed espe' valuable maritime service' by cially for B-Eliminator providing fog signals, to be sent Voltage Control. The out from the various lighthouses extra long columns of scientificall y·trea ted in the United States. . graphite discs insure Are You Building This recent innovation in the perfect voltage control field of the small power plant is over a wide range. It one that is extremely important is made in several a B .. Eliminator? and yet is novel and unique. At ranges for various B­ Eliminator circuits. F so, follow the example of most of the dangerous points in I leading radio engineers and the various navigable waters of use the Bradleyohm·E and Brad­ the United States, the govern­ ment has installed a safe and ac­ leyunit·A for your voltage con· curate plan for determining the B~'A trol location of the ships by radio fog PERFECT FIXED nESISTOn. Most of the well-known factory signals, operated by electrical built B·Eliminators are equip· energy, supplied by Westing­ ped with Bradleyohms as stand· house light and power plants. ardequipment. Surely, no better In order to insure against fail­ Bradleyunit-A is a recommendation of the relia­ ure of these fog signals the type solid molded resistor bility and stability of the Brad­ chosen was a three hp., four cycle, for radio circuits. It leyohm can be asked. single cylinder, valve in-head, air is molded and hea t­ cooled engine; with a rating of treated under high Build permanent performance 1% kw. and for use on 110 volts. pressure, making it and high efficiency into your It operates at 1200 rpm. on kero­ impervious to mois­ B·Eliminator by asking your sene or natural gas. ture. The silver­ dealer for Bradleyohm·E and capped ends can be These light and power plants soldered without Bradleyunit-A for your circuit. are now being installed at such affecting the calibra­ points as the Galveston Jetty, at tion of the Bradley­ Galveston, Texas, San Francisco unit. Harbor, Detroit River Light­ 6Ilen-B~ Co. house in Michigan, Cape Spencer 289 Greenfield Ave., MILWAUKEE, WIS. Lighthouse, Alaska, Buffalo, N. Y., and others making up a total of forty-six in all. Use 6ILen-B~ Perfect Radio Devices ? Please mention Radio Age when writing to advertiser8 S2 RADIO AGE for October, 1926 The Magazine of the Hour

COLISEUM···CHICAGO October 11 to 17 inclusive, 1926 PRESENTED BY RADIO MANUFACTURERS' SHOW ASSOCIATION 127 N. Dearborn St., Chicago 1800 Times Bldg., New York City "The World's Foremost Radio Expositions" HGreatest, Newest Developments Shown in Radio"

New Surface Finish NOUNCEMENT has just A been made of a new finish known as "crackle surface" which may now be had on hard rubber panels, made by the American Hard Rubber Co. This surface somewhat resembles a coarse grain, high grade leather. The surface can be engraved as is the case with a smooth finish panel yet it does not show ordi­ nary scratches or finger marks. The back of the panel is pol­ ished as usual so a choice of either side is available. It is made in the standard sizes.

Small Joins Verges AUL SMALL, one of Amer­ TUNE IN} P ica's most popular radio fa­ for Bie vorites, formerly of Little & MARVElOUS NEW AUDIO Small, the Radio Troubadours, TRANSFORMER adda a mu­ PROFITS. sics! quality to Iny let far hI­ and writer of several song hits yond am,thln!!: you ever hoard befon. KARAS HARMONI K of the day, has joined Joe AmpJlfle~ low. middle and I1lgh tones-all to the same hl~ vol­ Uffill, thU8 ellmlnatlnl distor­ Verges in a new harmony team, tion. Bdn,1 out the vital har­ monica and overtones of music. making their first radio appear­ Price S7.00. Write ance at WQJ recently. KarIS Electric Co., DepJ. IO~7. 4012 N. RfXkwdl Sf., ChicI,o Plea8e mention Radio Age when writing to udverti8(!r;! RADIO AGE for October, 1926 The Magazine of the Hour 53 WGN Moves Into New Studios N PREPARATION for the I unusual program of enter­ tainment and public service it is planning for the winter, WGN, Chicago, moved recently ~mlElLSJEA into its recently completed stu­ dios and control room on the twelfth floor of the Drake hotel. Products of one of the finest cp.Il/JItOllic Si.r engineering organizations pos­ sessed by any radio station, the Easily one of the real sensations of the year, the new studios and control room Chelsea Truphonic Six mu~ be seen and heard to be have been specially designed appreciated. Built by one of the olde~ radio manu­ and constructed to meet the var- facturers, noted the world over for its reliable products, this ious needs of the swiftly moving Chelsea receiver incorporates the new truphonic circuit, called day and night schedule of WGN. the greatest radio contribution of the season. The circuit is fully shielded. Since a power tube may be used in the last stage, The present studio facilities have tremendous amplification and a tone stability wholly new is now been taxed to the utmost, and obtained. when the enormous program de­ cIf,k Your Dealer To

'\~ Temperature Affects Two years ago Dr. Austin NoXO;sea! Signal Strength described a decided increase in Tones clearer. voices more distinct, and HAT temperature influences the signals received at Wash­ volume greater with-AMPERITE. No mov­ Tthe strength of radio signals ington from the Radio Corpora­ ing parts. It brings the utmost out of each tion trans-Atlantic stations at individual tube. Specified in all popular is the conclusion reached by L. construction sets. Price $1.10. Tuckerton and New Brunswick, W. Austin and Miss Wymore of N. J., during the passage of ~dial/ ecml'Q'!Y the Bureau of Standards, De­ severe cold waves over the Dept. R.A.-IO.SO Franklin Street. New York City partment of Commerce. This eastern states. Further study work is a part of the program now indicates that whenever of the International Union of the temperature rises along the Scientific Radio Telegraphy, signal path there is a tendency adopted at Brussels in 1922 and for the signal to drop; and con­ carried on in the various coun­ versely, a fal1ing temperatur~ Salt Lake City. Utah 246 KFQW C. F. KnierillL ______North Bend, \Vash_ 216 KF AB Nebraska Buick Auto Co ______.Lincoln, Keb. 341 KFQZ Taft Products Co. ______Hollywood, Calif. 225 KFAD McArthur Bros. Mercantile Co ______Phoenix, Ariz. 273 KFRB Hall I3ros. ______Bec,-ille, Texas 248 KFAF A. E. FowleL ______.5an Jose, Calif. 217 KFRC City of Paris Dry Goods Co. ______San Francisco, Calif. 268 KFAU Independent School Dist. ______.Boise, Idaho 280 KFRU Stephens College ____ .______Columbia, 11.10. 500 KFBB F. A. Buttrey& Co______Havre, 1-.lont. 275 KFR'V \Vestern Broadcasting Corp. ______Olyn-pia, \\'ash. 219 KFBC \V. K. AzbilL ______.San Diego, Calif. 216 I KFSD J\irfan Radio Corp. ______San Diego, Calif. 246 KFBK Kimball-Upson Co______. __ ._Sacramento, Calif. 248 KFSG Echo Park Evan. Assn ______.______Los Angeles, Calif. 275 KFBL Leese Bros _____.. ______Everett, \Vash. 224 KFUL Thomas Groggan & Bros. Music Co. ____ Galveston, Texas 258 KFBS School District No. One ______Trinidad, Colo. 238 KFUM \V. D. Corley, ___ . ______. ______Colorado Springs, Colo. 239 KFBU St. Mathews CathedraL ______Lararnie, \\\0_ 375 KFUO Concordia Seminary______St. Louis, Mo. 545 KFCB Nielson Radio Supply Co______Phoenix, Ariz_ 238 KFUP Fitzsimmons General HospitaL______Denver, Colo. 234 KFDD St. Michaels CathedraL______. ______Boise, Idaho 275 KFUR Peery Bldg. Co ...... _...... _..... _ ...... 'Ogdcn. Utah 224 KFDM Magnolia Petroleum Co ______Beaumont, Texas 316 KFUS Louis L. Sherman______c.. ______Oakland, Calif. 256 KFDX First Baptist Church______. __ Shreveport, La_ 250 KFUT University of Utah______Salt Lake City, Utah 261 KFDY South Dakota State College ______Brookings, S. D_ 306 KFUU Colburn Radio Labs. ______Oakland, Calif. 220 KFDZ Harry O. Iverson ______. ______l\'1inneapolis, l\linn. 231 KFVD l\Ic\\ ninnie Electric Co. ______San Pedro, Calif. 205 KFEC 1Ieier & Frank Co ______Portland, Ore. 248 KFVE Benson Broadcasting Corp.______St. Louis, l\Io. 240 KFEL Eugene P. O'Fallon, Inc. ______Denver, Colo_ 254 KFVG First 1\'1. E. Church__ . ______. ____ Independence, Kans. 236 KFEQ J. L. Scroggin ...... _.. _..•• .. _..... _ .. _. . _.. _...... Oak, p: eb. 268 KFVI Headquarters Troop, 56th Cavalry ______._Houston, Texas 240 KFEY Bunker Hill & Sullivan .l\lin. S: Con_ Co_ _Kellogg, Idaho 233 KFVN Carl E. Bagley______. ______. ____ Fairmont, Minn. 227 KFFP" First Baptist Church ______Moberly, Mo. 242 KFVS Hirsch Battery and Radio Co. ____ Cape Girardeau, l\lo_ 224 KFGQ Crary Hardware Co ______Boone, Iowa 226 KFVY Radio Supply Co. ______Albuquerque, N. 1\'1. 250 KFH Hotel Lassen ______; ____ \\'ichita, Kans_ 268 KFWB \Varner Bros. ______Hollywood, Calif. 252 KFHA \Vestern State College of Colo . ______Gunnison, Colo. 252 KF'VC L. E. \Val'--______._San Bernardino, Calif. 211 KFHL Penn_ College------Oskaloosa, 100va 240 KF'VF St. Louis Truth CenteL ______St. Louis, Mo. 214 KFI E. C Anthony, Inc______~ ______LosAngeles, Calif. 468 KF'VH F. \Vellington 1\'I0IS(', Jr.______Eureka, Calif. 254 KFIF Benson Polytechnic I nstitute. ______. ____ Portland, Ore_ 248 KF'VI Radio Entertainments, Inc. __ South San Francisco, Calif. 226 KFIO North Central High SchooL ______Spokane, \\'ash. 265 KF'VI\I Oakland Educational Society______Oakland, Calif. 207 KFIQ First Methodist Church ______Yakima, \Vash_ 25t> KFWO Lawrence M:otL ______.Avalon, Calif. 211 KFIU Alaska Electric Light & Power Co______Juneau, Alaska 226 KF'VU Louisiana College ______Pineville, La_ 238 KFIZ Daily Commonwealth ______Fond du Lac, " Tis_ 273 KFWV \\Tilbur Jerman ______Portland, Ore. 213 KFJB IVIarshall Electrical Co ______l\la rshalltown, Iowa 248 KFXB Bertram O. H~lIer..------.------I3ig Bear Lake, Calif. 203 KFJC -R_ B_ Fegan (Episcopal Church}___ -1unction City, Kans_ 219 KFXD Service Radio Co. ______Logan, Utah 205 KFJF National Radio Manf. Co_. ____ . _____ Oklahoma City, Okla. 261 KFXF Pike's Peak Broadcasting Co. __ Colorado Springs, Colo_ 250 KFJI E_ E_ l\larsh ______Astoria, Ore_ 246 KFXH Bledsoe Radio Company__ . ______EI Paso, Texas 242 KFJl\I University of North Dakota ______Grand Forks, N. D. 278 KFX J Mt. States Radio Dist. Inc __. ______Denver, Colo. 216 KFJR Ashley C Dixon & Son ______Portland, Ore_ 263 KFXR Classen Film Finishing Co_. ___ . ____ .Oklahoma City, Okla_ 214 KFJY Tunwall Radio Co______Fort Dodge, Iowa 246 KFXY l\ Iary 1\1. Costigan------Flagstaff, Ariz. 205 KFJZ W. E. Branch..... _ .. _..... _.. _..... _...... _.. . Ft. \\'orth, Tex. 254 KFYF Carl's Radio Den______._._Oxnard, Calif. 205 KFKA Colo_ State Teachers College_._. ______Greele y, Colo. 273 KFYJ Chronicle Publishing Co .. ______Houston, Texas 238 KFKU The University of Kansas ______Lawrence, Kans.275 KFYO Buchanan-Vaughan Co ______Tcxadmna, Tex. 210 KFKX \Vestinghouse Elec. & Mfg. Co ___ _. ______Hastings, Neb_ 288 KFYR Hoskens-l'vleyers, Inc. ______. __ Bismarck, N. Dak_ 24& KFKZ Chamber of Commerce ______Kirkville, 1\/10. 226 KGAR Tucson Citizen ______Tuscon, Ariz. 244 KFLR University of New l\J exi co ______A lbuqucrque, N. M. 254 KGBS A. C. Dailey...... _ ...... _ ...... _... Seattie, Wash. 210 KFLU San-Benito RadioClub______San Benito, Texas 236 KGBU R. R. Thornton ______>______Ketchikan, Alaska 229 KFLV Swedish Evangelical Church ______Rockford, Ill. 229 KGB'" l\Iartin Brotherwn ______Joplin, 1\10. 283 KFLX George RoyClough ______._Galveston, Texas 240 KGBX J. A. Abercrombic______.5t. Joseph, Mo. 348 KICK Atlantic Automobile Co. ______Anita, la. 273 KGBY Albert C. Dunning______.______.5helby, Nebr. 203 KFMR l\Iorningside College------Sioux City, Iowa 261 KGBZ Fedcral Livestock Remedy Co. ______York, Nebr. 331 KFMX Carleton College ______Northfield, :Minn. 337 KGCA C \V. Greenley ______.. ___ .______Decorah, Iowa 280 KFNF Henry Field Seed CO. ______.Shenandoah, Iowa 461 KGCn \Vallace Radio In stitute______.Dklahoma, Okla. 331 KFOA Rhodes Department Store ______. ______SCa ttle, \Vash. 454 KGCG I\Ioore ' n.'fotor Co ..... ___ .. ______Newark. Ark. 234 KFOB Chamber of Commerce. ______Burlinga me, Calif. 226 KGCI International Radio Co., ______San Antonio, fexas 240- KFON Echophone Radio Shof.______Long I3each, Calif. 233 KGCH \Vayn~ HospitaL ______\Vayne, Nebr. 450 KFOO Latter Day Saints! Uni,·ersity____ .Salt Lake City, Utah 236 KCO Generall!.lectric Co. __ . ______. ______'Oakland, Calif. 361 KFOR David City Tire & Electric Co __ ___ . __ __ David City, Neb_ 226 KGTT Glad Tidings Tabernaclc __ .___ San Francisco, Calif. 207 KFOT College Hill Radio Club_. ___ _. ______\Vichita, Kans. 231 KGU l\larion A_· l\Iulrony ______Honolulu, Hawaii 270 KFOX Board of Education, Tech. High SchooL __ Omaha, Nebr. 248 KGW Portland Morning Oregonian __ . ______Portlanu., Oreg- 491 KFOY Beacon Radio Service ______St. Paul, :\Jinn. 252 KGY SL Martins Collegc. ______. ______Lacy, \Vash. 278 KFPL C. C. Baxter__ . ______Dublin, Texas 252 KHJ Times-lVIirror Co .. ______. ______Los Angeles, Calif. 405 KFPM The New Furniture Co. ______.______.. Greenville, Texas 242 KHQ Louis \YasmeL. ______Seattlc, \Vash_ 394 KFPR Los Angeles County Forestry DepL_Los Angeles, Calif. 231 KJBS J _ llrunton.& Sons______San Francisco, Calif. 220 KFPW St. 10hns M. E_ Church ______. __ Carter..-ille, Mo. 258 KJR Northwest Radio Scn-ice Co ______. ___ . _____ Seattle, \Vasll. 384 KFPY Symons Investment Co. ______Spokane, \Vash_ 273 KLDS Reorganized Chun:h ______. ______Jnclcpcmlence, Mo. 441 KFQA The Principia______.______St. Louis, Mo. 261 KLS \Varner Brothers Radio Supplies Co. ____ Oakland, Calif. 250 KFQ8 -The Searchlight Publishing Co. ______Fort \Vorth, Texas 263 KLX Tribune Publishing Co. ___ . __ ~. ______. __ Oakland, Calif. 508 KFQI> Chovin Supply Co ...... _...... Anchorage. Alaska 227 KLZ Reynolds Ri:l..di.Q Co. __ , ______.• _.. ______Denver, Colo. 266 RADIO AGE for October, 19:16 The Magazine of Ihe flour S5 Effect of Northern Lights on Radio Described r-rO what extent Northern lights affect radio reception in the Arctic circle is outlined in a de­ tailed report delivered today to Denver's General Electric broad­ Circular casting station, KOA. No. 1015 The communication was writ­ ten by Sgt. Fra nk A. Barnes of Describing the Royal Northwest Mounted police, Coronation gulf, N orth­ The west territories, and was seven months on the way. New Jewell "As the green and gold lights sweep across the blackened sky Tip-Jack there is a corresponding rise and 135-A Tip-Jack Voltmeter fall in radio reception," writes (7 y, and 150 Volts) Voltmeter Sergeant Barnes. "An unusually brilliant flash of flaming red and Owners of the n ewer sets in which manufacturers have inst a lled yellow lights puts the instrument two tip-jacks on the panel, should write to us for circular No. 1015. The new J ewell tip-jack voltmeter not only has two ad­ out of commission." justable prods, to fit varying horizonta l spacing of t h ese jacks, b ut Sergeant Barnes aso noted the back plate can be rotated to fit set s having pin-jacks placed that howling blizzards and icy, vertica l, o ne a bove the othe r. It has a high resist a nce m ovem ent stormy weather and the sunless a nd is o f the highest quality. months of November, December All tubes have a rated voltage Don't burn them too high Or and January afford the best re­ ception. "No stations are received in daylight, but particularly good I J;;:11 Ele~lrj!?"~! '!~~~oument CO. results are obtained during the "26 Yea rs Making Good Instruments" second and third quarters of the - -- moon," Sergeant Barnes explains. "Some nights we r eceive all over the United States; other nights, all eastern stations or all western," the letter continues. "Stationed on the frozen outposts of the earth, radio is our only contact with a white man's world . "Your programs come over to us most clearly and frequently. --say those In four months, we have listened to your programs exactly ninety who use times." A&-B8allery ~2 Cllarger ONiY . SATISFACTION GUARANTEED Charges any type of storage A or B battery, using a few cents worth The Cushiolt Base lube is HEIR use in your set will elimi­ of ordinary house cur­ a Van Horne development T nate microphonic t rouble--will manufactured only by the rent, either alternating Van Horne Company IIn­ smooth out reception-and give t hat or direct. Cannot injure der patents pending to J. f uIlness and clearness of tone that you battery. C o mpl ete S. Van Home. A variety have always desired. directions e n c1 a sed. oj t1lbe types in both the Anyone can operate. Van H orne Selected and Put a set of Cushion Base tubes in No expensive "extras" Certified brands are man­ your set and note what an improve­ t o buy. Why pay ufactured, aU of which are $ 10.00 to $ 15.00 for a charger when you ment the soft sponge rubber cushion can get this splendid GUARANTEED R. B. unconditionally guaran­ makes. Charger by mailing us two dollars (bills. money. teed. order, check or stamps) plu5 ten cents in stamps or Order a set from your dealer today. coin to pay mailini!! costs. Charger will be sent postpaid. If you are not Mtisfied. return wit hin five days and we will r efund your money. Order THE VAN HORNE COMPANY, Inc. at once-TODAY;-- 92 Center Street, FRANKLIN, OHIO R. B. SPECIALTY COMPANY Dept. Xl, 308 East: Third 5t:., Cincinnati, Ohio Please mention Radio Age when writing to advertisers 56 RADIO AGE for October, 192f The Magazine of the Hour

KMA !\Iay Seed & Nursery Co... ______Shenandoah , Iowa 461 WAIT A. H. Waite Co ... ____ ..___ ...... ______Tuantoll t hIass. 229 KMJ Fresno B~ ______Fresno, Calif. 231 WAIU American Insurance Union ______Columbus, Ohio 294 Kivlj\IJ 11. 1\.1. Johnson Co. ______Llay Center, Nebr. 229 WAMDRadisson Radio Corp. ______. __ Minneapolis, I\Iinn. 244 KMO Love Electric Co .. ______Tacoma, \Vash. 250 WAPI Alabama Polytechnic Institute ______.Auburn, Ala. 248 Kl\IOX Voice of St. Louis. ______.. ______St. Louis, 1\10. 280 'VARC American Radio & Research Corp._____ J\.Iedford, Mass. 261 KUTR Turner Radio Corp.______Los Angeles, Calif. 238 WATT Edison Electric. ______: ______Boston, Mass. 244 KNRC C. B. Juneau..______.. ___L os Angeles, Calif. 208 \VBAA Purdue University______\V. Lafayette, Ind. 273 KNX Los Angeles Evening Express. ______l...o s Angeles, Calif. 337 'VBAK Pennsylvania State Police. ______Harrisburg, Pa. 275 KOA General Electric Co. ______.. ______Denver, Colo. 322 WBAL Consolidated Gas & Elec. Co. ______Glen l\lorris, Md. 24.6 KOAC Oregon Agricultural College. ______Corvallis, Oreg. 280 \VBAO James Mileikan University______Decatur, 111. 270 KOB N . Mex. College Ag. & I\Ie. Arts._.State CoIlege.N .1\Iex. 349 WBAP \Vortham-Carter Pub. (Star Telegram) Ft.\\~orth,Texas 476 KOCH Central High SchooL______Omaha. Neb. 258 \VBA'V Braid Elec., & \Valdrum Drub Co .... ____ N"ashville, Tenn. 236 KOCW Oklahoma Col1ege for \Vomen ______Chickasha, Okla. 252 'VBAX 10hn H. Stenger, Jr.______\Vilkes-Barre. Pa. 256 KOIL Monarch Manufacturing Co ______CounciI llIuffs, Iowa 278 WBBC P.]. Testan______Brooklyn, N. Y. 250 KOIN Inc. ______Sylvan, Ore 319 WBBL Grace Covenant Presbyterian Church ___ Richmond, Va. 229 K01\IO Bert F. Fisher. ______Seattle, \Vash. 306 'VBBM Atlass Investment Co .. ______. ______Chicago, Ill. 226 KOW\,\, Blue Mt. Radio Assn. ______\ Vall a \Ya11a, \Vash. 285 'YBBP Petoskey High SchooL ______.Petoskey, Mich. 238 KPO Hale Bros.. ______San Francisco, Calif. 428 WBBR People's Pu1pit Assoc.. ______Ross\-;lIe. N. Y. 416 KPPC Pasadena Presbyterian Church ______Pasadena. Calif. 229 WBBS First Baptist Church ______New Orleans, La. 252 KPRC Houston Post Dispatch. ______Houston, Texas 297 ·WBB\V Ruffner 1 unior High SchooL______Norfolk, Va. 222 KPSN Star-Kews Publishing Co. ______Pasadena. Calif. 316 \-VBBY \Vashington Light Inf.Co."B"118th inf.Charieston,S.C. 268 KQV Doubleday-Hill Electric Co. ______Pittsburgh, Pa. 275 WBBZ C. L CarreIL______Chicago, Ill. 216 KQW Charles D . Herrold ______. ______.5an Jose, Calif. 333 \VBC~ Foster & UcDonne1L ______Chicago, Ill. 266 KRE Berkeley Daily Gazette______Berkeley. Calif. 256 \VBDC Ba.xter Laundry Co .. ______..______Grand Rapids, Mich. 256 KSAC Kansas State Agricultural CoIlege. ___ 1Ianhattan, Kans. 341 'VBES Bliss Electrical SChooL. ______~ ______Takoma Park, ~Id. 222 KSD Pulitzer Printing Co.. ______St. Louis. 1\10. 545 WB~Y B. A. Ruchome Corp .. ______. ______New York, N. Y. 322 KSL R adio Service Corp. of Utah ______Salt La ke City, Utah 300 WBOQ A_ H_ Grebe & Co., Inc. ______Richmond Hill, N_ Y_ 236 KSMR Santa .Maria Valley Railroad Co. ____ Santa 1 laria, Calif. 210 \\'BPI I. R. K elson ______. __ Newark, N .1. 263 KSO A. A . Berry Seed Co. ______"Cla rinda, Iowa 242 '''BRC Bell Radio CorporatioIl. ______Binningham, Ala. 248 KTAB Associated Broadcasters______.. Oakland. Ca lif. 303 \"BRE Baltimore Radio Exchange..______\Vilkes-Barre, Pa. 231 KTBI Bible Institute. ______Los Angeles, Calif. 294 WBRS Universal Radio Mfg. Co.______..______Brooklyn, N. Y. 394 KTBR M . E . Brown ______Portland, Ore. 263 WBT Charlotte Chamber of Commerce._____ .charlotte, N. C. 275 KTHS New Arlington Hotel Co.. ______Hot Springs. Ark. 375 'VBZ \Yestinghouse Elect. & 1\Ifg. Co. ______Springfield, Mass. 331 KTNT N. Bak~ ______l\1uscatine, Iowa 333 \VBZA \Yestinghouse Elect. & J\Hg. Co.. ______Boston, Mass. 242 KTU E Vhalt Electric Co. ______H ouston, Texas 265 \"CAG Connecticut Agricultural College.. ______Mansfield. Conn. 275 KT\V First Presbyteria n Church ______Seattle,.\\7ash. 454 \VCAD St. Lawrence University ______Canton, 1\-. Y. 263 KUOA University of Arkansas ______Fayette\·iIle, Ark. 300 \VCAE Kaufman & Baer Co. & The Pitts. Pr ___ Pittsburgh, Pa. 461 KUOM_State University of l\ Iontana ______l\ Iissoula , 1\ [ont. 244 \VCAJ Nebraska \Vesl~yan University __ University Place, Nebr. 254 KUSD University of South Dakota ______\·ermillion, S. D. 278 WCAL St. Olaf College ______Northfield, Minn_ 337 KUT University of T exas______.Austin, T exas 231 \VCAM City of Camden ______.Ca mden, N.1. 236 KVOO The Voice of Oklahoma.. ______Bristow, Okla. 375 \VCAO A. A. a; nd A. S. Brager______Baltimore, Md. 275 K\YCR H. F . Paar. ______Cedar Rapids, Iowa 278 \YCAP Ch esa~a ke & Potomac Tel. Co .. ______\Vashington, D. C. 468 KWG Portable " 'ireless T elephone Co.______Stockton, Cali f. 248 " 'CAR Southern Radio Corp. of Texas______San Antonio, Texas 263 K\VKC \Vilson Duncan Studios ______.Kansas City, Mo. 236 WCAT State College of Mines______Rapid City, S. Dak. 240 KWKH Henderson Iron \Yorks __ .. ______.5hreveport, La. 312 WCAU Universal Broadcasting Co.. ______Philadelphia, Pa. 278 K\VSC State CoIIege ______Pullman, ' Yash. 349 \VCAX Pni\'ersit y of \ 'ermont..______Burlington, Vt. 250 KWUC\Vestern Union College.. ______.Le :" lar5, Iowa 252 \VCBA Charles \Y. Heimbach______.Allentown, Pa. 254 KWWG City of Brown sville. ______Browns\'iIle, Texas 278 WCBD Wilbur C. Voliva.______Zion, Ill. 345 KY\V \Vestinghouse Electric & Mfg. Co. ______.. ____Chicag o. ilL' 535 WCBE l Thalt Radio Co ______..______New Orleans, La. 263 KZIB l. Bec"-______Manila, P _ I. 250 \VCBH University of Mississippi.______'Oxford, Miss. 242 KZKZ Electrical Supply Co ..______l\ lanila, P. I. 270 \VCBl\r Charles Swarz. ______•____ .._. ______Baltimore, Md. 229 KZM Preston D. Allen ______Oakland. Calif. 240 \VCBR C. H. J\I ester.. ____ .______Providence, R. 1. 210 KZRQ Far Eastern Radio ______. __._ .. ______. ____ l\Ia nila. P. I. 222 WCBS H. L. Dewing, Portable _____ . ______Prm;dence, R. 1. 242 KZUY F_ J . Elser______1 Ianila, P . I. 360 \VCCO \Vashburn-Crosby Co .. ___ . ______. ______Anoka. J\rinn. 416 NAA U. S. Nay·}' DepL ______.Arlington, \ 'a. 434 \YCFT Knights of Pythias ______Tullahoma, Tenn. 252 WAAD Ohio Mechanics Institute. ______Cio.cinnati, Ohio 258 \VCLO C. E . \VhitnlOre ______Camp Lake \Yis. 231 \VAAF Chicago Daily Drovers J ournaL _____ .. ______Chicago, Ill. 278 WCLS H_ ~l. Couch ______J oliet, Ill_ 214 WAA W Omaha Grain Exchange______'Omaha, Nebr. 278 \YCMA Culver l\ Iilitary Acarlemy ______Culver, Ind. 258 \VABB Harrisburg Radio Co... _. __ _ ..______Harrisburg, Pa. 204 WCOA City of Pensacola______Pcnsacola, Fla. 222 W ABC Asheville Battery Co., Inc. ______.Asheville, N. C. 254 WCRW Clinton R_ \\'hite. ______Chicago, IlL 416 WABI 1st Univeralist Church ______Bangor, Me. 240 'VCSH Henry P. Rines. ______. ______Portland, Maine 256 WABO Lake Avenue Baptist Church______Rochester, N. Y. 278 \VCSO \Vitten berg Coller,e. ______. ______.Springfield, Ohio 248 WAB O Haverford College, Radio Club____ ..____ .. _Haverford. Pa. 261 " 'CWS Chas. \Y. Selene (Portable).. ______Providence, R. 1. 210 WA BR Scott High SchooL ______Toledo, Ohio 263 \VCX Free Press and J ewett R. & P. Co. ______Detroit, Mich. 517 ' YA B\Y College of \Yooster. ______.. ______\\·ooster, Ohio 207 'VDAD Da d's Auto Accessories, Inc.. ______Kashville, Tenn. 226 WABX Henry B. J oy______1It. Clemens, Mich. 246 WDAE Ta mpa Daily Times______Tampa, Fla. 273 WABY John "Iagaldi, Jr ______Philadelphia, P a. 242 WDAF Kansas City Star..____ . ______.Ka nsas City, Mo. 366 WABZ Coliseum Place Baptist Church ______Xew Orleans, La. 275 'VDAG J. Laurence l\ lartin ______A marillo, Texas 263 \YADC Allen T. Simmons (A llen Theatre) ______.Akron, Ohio 258 \VDAH Trinity J\ Iet hodist Ch-u rch. _. ______EI Paso, Texas 268 \VAFD 'Albert B. Parfct Co. ______.._Port Huron, !\Iich. 275 ' VDA Y Radio Equipment Corp .. ______.Fargo, N. Da k. 261 \VA G:\I R.L. ~l iller. ______..______Roya 1Oak, ~ [ich . 225 WDBE Gilham-Schoen Elec. Co. ______. ______.Atlanta, Ga. 270 WAHG A_ H. Grebe & Co ______Rirhmond Hill, K_ Y_ 316 WDBJ Richardso n Wayland Elec. Corp .. ______Roanoke, \ 'a. 229 RADIO AGEJor October, 1926 The Jvlagazine oj the Hour 57 Radio Religious Programs Fill the Churches WHY GUESS Mica Condensers ADIO religious programs The B Voltage Delivered? R are filling the churches rather than emptying them, This is the trend in­ dicated by a survey of sacred broadcasting just made by Sears-R 0 e b u c k Agricultural Foundation, Returns show that the church which broadcasts is on its mettle when it knows the world is listening in and puts an added zest into the music and' service that brings people into the church instead of encouraging them to take their religion in comfortable doses at home. in the One church in New Jersey states that since its services have begun to be sent out on the air, Stromberg -Carlson the gallery pews have been There are no knobs to opened up and dusted off for turn on the Bremer-Tully RECEIVER the first time in twenty years, B-Power unit, Cartridge type fixed re­ ADIO ~nthusiasts sat up and listened The church that does not R when the opportunity came to hear broadcast, on the other hand, sistances are furnished. A the Stromberg-Carlson receiver. That feels the competition and makes chart shows the ones to use firm's name means quality. Their set won every effort to bring its services for your set, Insert the re­ a leading place immediately in a market and sermon up to the standard that seemed over-crowded wth good sistances and there is noth­ makes. No claims are made of revolu­ of the radio churches, ing further to be done, tionary ideas in new circuits, but every One hundred and seventy­ part is made with scientific precision. eight radio stations from every When purchasing a B-Power Unit, more stress should be laid Sangamo Mica Condensers are used in part of the United States and in on the ability and integrity of the Strongberg-Carlson becaus~ they are Canada from the Saskatchewan the manufacturer than on any permanently accurate. Sangamo con­ to Montreal, participated in this other radio product. densers are solidly molded in bakelite. All edges are sealed tight: no moisture survey, One hundred and three INVESTIGATE B-T! can creep in to change the capacity. Their of these stations, or sixty per Read "Better Tuning"-It tells accuracy is guaranteed to be within 10 cent, are giving some sort of about the new B-Power Unit and per cent and to remain unchanged. religious service or sacred music new sets. Distinctive in appearance, too; com­ PI ice IOc Circulars free. pletely enclosed in velvet-smooth brown as a part of their regular pro­ bakelite; all corners rounded to prevent grams, Four per cent are con­ chipping; reinforcing ribs for mechanical sidering adding this feature and strength. six per cent have religious ob­ Experiment with "world-beater" cir­ servance only on such occasions cuits if you will-but remember that as Christmas, Easter and Holy accurate Sangamo Mica Condensers will Week. improve the tone and range of any set. You can fit your set exactly-there are 'Fourteen of these 103 stations 35 capacities to choose from. are owned or operated by some church or religious body, The Tried SANGAMO rest simply include these fea­ DEALERS SELLING BY-PASS CONDENSERSl tures along with secular pro­ COUNTERPHASE SETS They stand the surges di~play this aign without breaking down. grams, because they feel their audiences want and appreciate BREMER-TULLY MFG. CO. them, 520 So. Canal St. SangaIllo Electric COIllpany Chicago, Ill. 6332-8 Springfield, lIIinois Most On Sundays ______COUPON______

RADIO DIVISION, 50 Chu,ch SUeet, New Yo,' S UNDA Y is the day that 86 of Please send 10th Edition "Better Tuning." these stations send out their lOc enclosed 0 Free circulars 0 SALES OFFICES-PRINCIPAL CITIES sacred programs while 22 are on ForCanada-SangamoT~:;~~c Co. of Canada, Ltd .. week-days. The week-day pro- NAME

For Europ:!-Brit~tdJ:~~:nEn;O" Ponders End, g'rams consist of sacred music or ADDRESS FocF" E",-A,h;da Eng;n",;ng Co.. O",ka, japan instructional address, A num- Please mention Radio Age when writing to advertisers 58 RADIO AGE for October, 1926 The Maga,ine of the Hour

WDBK M. F. Droz.. ______Cieveland, Ohio 227 WHAS Courier-Journal & Louisville Times.______Louisville, Ky. 400 WDBO Rollins College, Inc. ______.\Vinter Park, Fla. 240 \VHAZ Rensselaer Polytechnic Institute______. _____ Troy, N. Y. 379 WDnZ Kingston Radio C1ub. ______.Kingston, N. Y. 233 WHB Sweeney School Co. ______Kansas City, Mo. 366 WDEL Wilmington Eke. Specialty Co. ______\Vilmington, Del. 266 WHBA C. C. Shaffer_ ...... ______.. ______.. ______'Oil City, Pa 250 WDG Y Dr. George \V. Young._____ . ______I\ J inncapolis, Ivl inn. 263 WHBC Rev. E. P. Graham ______._Canton, Ohio 254 WDOD Chattanooga Radio Co., Inc. ______.Chattanooga, Tenn. 256 \VHBD Chamber of Commerce______Bellcfontaine, Ohio 222 WDRe Doolittle Radio Corp. ______.Ncw Haven, Conn. 268 WHBF Beardsley Spccia,lty Comp3.ny______. __ Rock Island, Ill. 222 \\'DWF Dutee \Vilcox Flint, Inc. ______.Cranston, R. I. 441 WHBG John S. Skane______Harrisburg, Pa. 231 WDZ J. L. Bush._ .. _. ____ ...... _ .. _.. _.. ___ .. _.. _.. _ .. _.. .Tuscola, Ill. 278 WHBJ Lauer Auto Co. ______. ______Ft. 'Vayne, Ind. 234 'VEAF Broadcasting Co. of Arncrica... ______.Ncw York, N. Y. 491 WHBL C. L. CarreIL______.. ______.. ______Chicago, Ill. 216 'VEAl Cornell Univcrsity______Ithaca, N. Y. 254 'VHBM C. L. Carrell, (Portable Station) ______. __ Chicago, Ill. 216 WEAM Bar. of N. Plainfielcl ______North Plainfield, N. J. 261 \VHBN First Ave. Methodist Church______.5t. Petersburg, Fla. 238 WEAN Shepard Co. ______Providcnce, R. I. 367 WHBP Johnstown Automobile Co._. ______. ____ Johnstown, Pa. 256 WEAO Ohio State University______Columbus, Ohio 294 WHBQ St. John's M. E. Church South ______Memphis, Tenn. 233 \VEAR \Villard Battery Co. ______Cle...-eland, Ohio 389 WHBU Riviera Theatre & Ring's Clothing. ______Anderson, Ind. 219 WEAU Davidson Bros. Co. ______..5ioux City, Iowa 275 WHBWD. R. Kienzle_ .. ______.. ______.. ______... Philadelphia, Pa. 216 WEBe \Valter Cecil Bridges______..5uperioi, \\~is. 242 I WHBY St. Norbert's Collegc... ______\Vest de Perc, \Vis. 251) WEBH Edgewater B. H. & Herald Examiner______Chicago, Ill. 370 WHDI \V. H. Dunwoody Ind. Institute. ____ l\'linneapolis, Minn. 278 WEBJ Third Avenue Railway Co.______Kew York, N. Y. 273 WHEC Hickson Electric Co., Inc. ______~ ___ Rochester, N. Y. 258 WEBL Radio Corp. of America (Portable) ___ J\ew York, N. Y. 226 I WHFC Hotel Flanc1ers. ______. __ . ______.. __ Chicago, Ill. 258 WEBQ Tate Radio Corp. ____ . ______Harrisburg, Ill. 226 WHK The Radio Air Service Corp. ______Cleveland, Ohio 273 WEBR H. H. HowelL______Buffalo, N. Y. 244 \VHN George Schubert.______New York, N. Y. 361

WEBW Beloit College.. ______lleloit, \Vis. 268 \VHO Banker's Life Co. ______~ _____ . ______Des Moines, la. 526 WEBZ Savannah Radic Corp______. ______Savannah, Ga. 263 I WHT Radiophone Broadcasting Corp. ______Deerfield, Ill. 238 WFCI Frank Crook, Inc.______Pawtucket, R. L 229 'VHT Radiophone Broadcasting Corp. ______D.eerfield, Ill. 400 WEE] The Edison Elec. Illuminating Co. ______Boston, Mass. 349 I \VIAD Howard R Miller. ______Philadeiphia, Pa. 250 WEHS Robert E. Hughes. ______Evanston, Ill. 203 WIAS Home Electric Co. ______. ______Buriington, Iowa 254 WEMC Emanuel Missionary College ______Berrien Springs, Mich. 285 WIBA The Capital-Times Studio.. ______i\.Iadison, \Vis. 236 WENR All-American Radio Corp .. ______Chicago, III. 266 \VIBG St. Paul's Protestant E. Church. ______Elkins Park, Pa. 222 WEW St. Louis University______St. Louis, Mo. 360 WIBH Elite-Radio Stores______New Bedford, Mass. 210 WFAA Dallas News & Dallas JournaL______Dallas, Tex. 476 WIBI Frederick B. Zitteli, Jr. ______Flushing, N. Y. 219 WFAM Times Publishing Co. ______St. Cloud, 1\.Iinn. 273 WIBJ C. L. Carrell {Portablc) .. ____ .. ______Chicago, 111. 216 WFAV University of Nebraska______Lincoln, Neb. 275 WIBM Billy Maine (Portable). ______..____ Chicago, 111. 216 WFBC First Baptist Church... ______Knoxvi lle, Tenn. 250 WIBO Nelson Brothers______Chicago, Ill. 226 \VFBE John Van Dc \Vallc... ______Seymour, Ind. 226 WIBR Thurman A. Owings. ______\\'erton, \V. Va. 246 WFBG The Wm. F. Gable Co .... ____ .. ______.Altoona, Pa. 278 WIBS T. F. Hunter {portable)______.. ______Elizabeth, N. J. 203 \VFBH Peoples Broadcasting Corp ______New York, N. Y. 273 WIBU The Electric ·FarITL ______~ ______Poynette, \Vis. 222 \VFBJ -St. John's U niversity______. ______Collegcville, Minn. 236 WIBW Dr. L. L. Dill_ .... ______Logansport, Ind. 220 \VFBL Onondaga Hotel Co. ______Syracuse, N. y_ 252 WIBX WIBX, Inc .. ______.... ___ Utica, N. Y. 234 WFB1\:[ 1\.Ierchants Heat & Light Co ______.Indianapolis, Ind. 268 WIBZ A. D. Trum______. ______. ______I\Iontgomery, Ala. 231 WFBR Fifth Inf. rVId. Nat'l Guarcl ______.Baltimore, l\.Id. 254 \VIL Benson Radio & The StaL______. ______St. Louis, Mo. 273 WFBZ Knox College ______. ______. ______Galesburg, III. 254 WIOD \Vonderful Isle of Dreams______. ______Miami, Fla. 248 WFCI Frank Crook, Inc. ______. Pawtucket. R. I. 229 WIP Gimbel Bros. ______. ______Philadelphia, Pa. 508 WFCL Chicago Federation of LaboL______Chicago, Ill. 491 WJAF Fenberg Radio Co. ______.. ______. ______Ferndale, l\Iich. 400 WFDF F. D. Fallain ______.______.. _____ . Flint, Mich. 234 WJAD Jackson's Radio Eng. Laboratories.______\Vaco, TeKas 353 WFI Strawbridge and ClothieL______._ Philadelphia, Pa. 394 WJAG Norfolk Daily News_. ______. ______Norfolk, Nebr. 270 WFKB F. K. Bridgman (Inc.) ______.. _____ .. Chicago, Ill. 217 WJAK Clifford L. White______Kokomo, Ind. 254 WFRL Robert l\Iorrison Lacey______llrooklyn, N. Y. 205 \VJAM D. M. Perham ______.. _. ______. __ Cedar Rapids, Iowa 26S WGAL Lancaster Elcc. Supply & Const. Co. ______Lanca!:lter, Pa. 248 WJAR The Outlet Co. (J.Samuels& Bro.L ___ .Providence, RI. 306 WGBB Ha;ry H. Carman. ______Freeport, N. Y. 244 \VJAS Pittsburgh Radio Supply House ____ . ______Pittsburgh, Pa. 275 WGBC First Baptist Church_. ______. ______l\Iemphis, Tenn. 278 \VJAX City of J acksonville______Jacksonville, Fla. 337 WGBF Fink Furniture Co. ______. ______Evansville, Ind. 236 WJAZ Zenith Radio Co. ______I\,H. Prospect, Ill. 322 \VGBI Scranton Broadcasters, Inc. ______Scranton, Pa. 240 WJBA D. H. Lentz, J'---______.. ___ .._Joliet, Ill. 207 WGBR George S. Ives ______.. ___ Marshfield, Wis. 229 \VJBB Financial JournaL ______.St. Petersburg, Fla. 254 WGBS Gimbel Brothers______Xew York, N. Y. 316 WJBC Hummer Furniture Co. ______. ______LaSalle, III. 234 WGBU Florida Cities Finance Co. _____ FuIford By-The-Sea, Fla. 278 WJBI Rober,S. Johnson _____ .. ______Red Bank, N. J. 219 WGBX University of Maine ______._Orono, Me. 234 WJBK E. F. Goodwin ______. ______. __ Ypsilanti, Mich. 233 WGCP May Ilroadcast Corp ______Newark, N. J. 252 WJBL \Vm. Gushard Dry Goods Co. ______Decatur, Ill. 270 WGES Coyne Electrical SchooL ______..______Chicago, l11. 250 \VJBO Valdemar Jensen. ___ ._. ____ .. _. __ . ____ ..____ Ncw Orleans, La. 268 WGHB Fort Harrison HoteL______._. __ . _____ . _____ Clearwater, Fla. 266 WJBR Geusch and Stearns______Omro, \Vis. 227 WGHP G. H. Phelps. ______"______Detroit, Mich. 270 WJIlT John S. Iloyd.. ___ .... ______. ______Chicago, 111. 238 WGM Verne and Elton SpenceL ______.Jeanette, Pa. 372 WJBU Bucknell Univcrsity______Lewisburg, Pa. 211 WGMUA, H. Grebe & Co. Inc. (Portable)Richmond Hill,N. Y. 236 WJBV Union Course Laboratories______\Voodhaven, N. Y. 470 WGN The Tribune______.. ______Chicago, Ill. 303 WJBW C. Carlson, J r. ______. ______. ______New Orleans, La. 341

WGR Federal T. and T. Co. ___ ~ ______. __ •______BufTalo, N. Y. 3[9 W JBX Henderson & Ross. ______Osterville, Mass. 280 WGST Georgia School T echnology_. ______. ____ .Atlanta, Ga. 270 WJBY Electric Construction Co. ______._. ______Cadsden, Ala. 270 WGY General Elec. Co. __ , ______.5chenectady, N. Y. 379 WJJD Supreme Lodge, L. O. of l\[oosc ______._Mooseheart, III. 370 'VHA University of \Visconsin ______l\.ladison, \Vis. 535 WJR Jewett Radio & Phon. Co. & D. F. P .. _____ Pontiac, Mich. 517 \VHAD l\-1arquett Univ. & Milw. JournaL______Milwaukee, \Vis. 275 WJY Radio Corp. of America ______New York, N. Y. 405 WHAM Univ. of Rochester (Eastman S. of M.)Rochester, N. Y. 278 WJZ Radio Corp?of America ______._. __ Bound Brook, N. J 454 WHAP \V. H. Taylor Finance Corp.______. ___ Brooklyn, N. Y. 431 WKAF \VKAF Broadcasting Co.______Milwaukee, 'Vis. 261 WHAR Seaside House_. ______.. ______.Atlantic City, N. J. 275 WKA Q Radio Corp. of Porto Rico ______. ______.5an Juan, P. R 341 RADIO AGEfor October, 1926 The lvlagazine of the Hour 59 ber have a brief service every morning somewhere between 7 and 8 o'clock. Actual church services are broadcast in 86 instances, w hi! e in 22 cases th e religious program is prepared especially for the radio and is sent out direct from the studio.

Forty stations report definite Lo~ Angelc3, CaliC. llawkesbury, Ont., Canada. Nauga.tuck, Conn. Fcrbcnd E I...,tr;c Co., Fl!rbend E lectric Co., Ferb.. nd Electric Co, cooperation from the ministers, Dcar Sirs; No doubt you will he Gentlemen, I am flleM.Sed to Gentlemen: My FEItDEND interested to know that we have inform yoU that I received "B" Eliminator bas been none report antagonism, while inHt&llcd your "D" Eliminator on the FERBEND " B" Elimin­ doing fine work since last eight dilTerent eight tube Super­ utoe and aftergi\-ing it a fair Deccmhcr. A f te r seven the rest did not mention this Heterodynes , and that everyone is teial am gl ad to say it has month,,' U ge will 'lay that I !lm very well plem.sed with it. giving complete ~Il tis.faction. ex.,eeded all my expe.,tatiOIlS. (Si~=d) Fr.. n.k S. Lobol ...l1. angle of the situation. One or (Si ~ned) I must ~a y it w...,; money well s pellt. (Sio,,~d) N ATION AL ELECTRI C CO. Lincoln, Nebr. two replies told of resentment Will Dooley. Ferbend E l e~l,ric Cu., Dea r S ir><; I have round YOUel and jealousy on the part of local "B" E liminator to bl! very slltidac:tory a nd too re ~ult:; clergymen who were not broad­ obtained weee even bettel tban the mOee e: satisfied wilh thl! machine. churches, but these were notable (Si"lUli) 11. W . Bradley. exceptions. Only two replies said that a decrease in church attendance could be traced to broadcasting, while 27 stated positively an in­ crease. One clergyman wrote, COMPLETE "Since we have been broadcast­ Dothing eIae to buy Re plaees ··B"Batter· ing our service Our church at­ ie'L Operates Direct from Electric Light Q;.., FERBEND-.G tendance has grown so rapidly Socket. that it is a problem to know how to take care of the crowds." "B' ELIMINATOR Another pastor wrote that forty Many careful buyers choose to adopt a policy of "watchful waiting." This is often true in the purchase of an apparently better, but yet-to-be-proved. automobile. The same holds persons had recently joined his good for many other commodities. And Radio. With the original announcement of the good Ferbend church, a direct result, he be­ "B" Eliminator and its amazing low price of $12. &). many there were who chose to wait. Theywanted to be convinced. True. thousands bought at the start and they aTe rhe OJles who JlOW lell you wha~ lieves, from radio broadcasting. to cxpecl. Lack of space alone prevents us from publishing the hundreds of fine testimonials from A Catholic station writes that satisfied users. They are all in our files open to public inspecton at any time. A few reproduced here. The Ferbend "B" Eliminator successfully passed the rigid Laboratory it has no effect on attendance in tests of Radio News, Popular Radio and Radio Broadcast.. It is a Pl'"o\led Catholic churches as its mem­ Radio necessity, and a great one. bers are obliged to attend every Ask Your Dealer-or Send Direc:t Sunday but that the radio fur­ -th~=;;1v"~~~.. Instru m~nt which If you prefer. we will make shipment direct to you upon recept of price, bSll h .... n wtd.,l~ Iml. tat

WKAR l\fichigan State College ______East Lansing, Mich. 285 WOAW Woodman of the World.._._ .. __ ._ .. _. ___ .. _... Omaha, Nebr. 526 \VKAV Laconia Radio Club______Laconia. N. H. 224 \VOAX Franklyn J. Wolff __ .. _.. _. ____ . __ . ______._. __ Trenton, N. J. 240 WKBA Arrow Battery Co. ______Chicago, Ill. 210 woe Palmer School of C-hiropractic..... _.. _... Davenport, Iowa 484 WKBB Sanders Bros ...... J oliet, Ill. 283 WOCL A. E. Newton._ .. _.. _...... _.. _.. _.. _ .. _._.Jarnestown, N. Y. 275 WKBC H. L. Ansley. ______Birmingham. Ala. 225 \VODA James K. O'Dea.. __ .._ .. _.. _.. ______..__ ._ .. _Paterson, N. J. 391 WKBD F. V. B,emer...... ~ ...... Je"ey City, N. J. 235 WOI Iowa State College ______. ___. ______Arnes, Iowa 270 WKBE K . & B. Electric Co. ______~ ______\Vebster, l\.'fass. 270 WOK Neutrowound Radio 1\Ifg. Co.... __ ._ .. _. __ Homewood, Ill. 217 WKBF N. B. Watson ______Indianapolis, Iod 244 WOKO Harold E. Smith_._ ...... ____ ..__ . _____ . __ ._ ... PeekskilI, N. Y. 233 WKBG C. L. Carrell (Po,table} ...... Chicago, Ill. 216 WOO John WanamakeL_.______. __ .. ___ ._ .. _. ___ ._Philadelphia, Pa. 508 WKBH Calla way 1\1 usic Co. ______LaCrosse, \Vis. 250 'VOOD Grand Rapids Radio Co._ .._ .. ____ ... Grand Rapids, l\lich. 242 WKBI F. L. SchoenwolL. ______Chicago, 111., 220 'VOQ Unity School of Christianity..... __ ._ ... Kansas City, Mo. 278 \VKBJ Gospel Tabernacle Inc. ______St. Petersburg, Fla 280 'VOR L. Bamberger and Co. ______. ______._N"ewark, N_ J. 405 WKDR Edward A. Dato_. ______. ______Kenosha, \Vis. 428 WORD People's Pulpit Assn ...... _.. _.. _.. _...... _.. __ .Batavia. Ill. 275 WKRC Kodel Radio Corp. ______. ______Cincinnati, Ohio 326 'VOS State Market Bureau_. __ .._ .. _____ ._ ... J efferson City, Mo. 441 WKRC Kodel Radio Corp. ____ .. _.. _ .. _.. _.. __ . _____ Cincinnati, Ohio 422 'VOWO Main Auto Supply Co_ .. __ ... _.. ____ ...... _Fort Wayne, Ind. 227 WKY WKY Radio Shop...... Oklahoma City, Okla. 275 WPAK N. D. Ag. College ____ . ___ .. __ . __ Agricultural College, N. D. 275 WLAL First Christian Church _____ . __ .._. __ .. _.. _. ___ ._Tulsa, Okla. 250 WPCC North Shore Congo Church_ ... _... __ ._ .. _.. __ .... Chicago, IiI. 258 WLAP Vlm. V. Jordan ______Louisville, Ky. 275 WPDQ H. L. Turner...... Buffalo, N. Y. 205 WLA Q Arthur E. Shilling______Kalamazoo, Mich. 283 WPG The Municipality of Atlantic City__ Atlantic City, N. J. 300 WLB University of 1\linnesota______J'vI inneapolis, l\linn. 278 WPRC \Vilson Printing & Radio Co ...... ___ ._ .. _Harrisburg, Pa. 216 WLBL Bureau of Marketing_____ .. _.. _ .. _._5teyens Point, \Vis. 278 WPSC Pennsylvania State College_ .. _.. _.. __ ..State College, Pa. 261 WLIB Liberty Magazine __ . __ . ______Elgin, Ill. 303 'VQAA Horace A. Beale, Jr. __ .._ .. __ ._ .._ .. __ ._ ... Parkersburg, Pa. 220 WLIT Lit Bros. ______.. __ ._ .. _.. _ .. _... Philadelphia, Pa. 394 'VQAC Gish Radio Service _____ . ______. _____ ... Arnarillo, Tex. 234 WLS Sears Roebuck & Co.. ______Crete, Ill. 345 WQAE Moore Radio News Station, ..__ .. _.. _... __ .. Springfield, Vt. 246 'VLSI Lincoln Studios... _.. __ ._ .._ .. _ .. _.. _.. _ .. _._C ranston, R. I. 441 WQAM Electrical Equipment Co ...... _. __ ._ .. _... _.. _._.Miami, Fla. 285 WLTS Lane Technical High SchooL._.. _ .. _.. _.. _.. ___ Chicago, Ill. 258 WQAN Scranton Times_____ . ______._. ______._ .. __ ._ ...Scranton, Pa. 250 WL'V Crostey Mfg. Co. ______. __ .. ____ . __ .. ____ Cincinnati, Ohio 422 \VQAO Calvary Baptist Church ___ .____ . ______. __ Cliffsi::le, N. J. 360 WL'VL Miss. Society of St. Paul the Apostle.J\'ew York, N. Y. 288 'VQJ Calumet Rainbo Broadcasting Co ...... _ .. _... Chicago, 111. 447 WMAC C. B. Meredith.. _. __ ._ .. _. __ .._ .. _.. _.. _...... Case novia, N. Y. 275 WRAF The Radio Club (Inc.} ...... _...... LaPorte, Ind. 224 WMAF Round Hills Radio Corp._ .. _.. _.. _. __ ._.Dartmouth, Mass. 441 \VRAH S. N. Read ______-. _____ . ______. _____ ..... Providence, R. I. 235 'Vl\1AK Norton Laboratories ______._ .. _.. _. ______.Lockport, N. Y. 266 'VRAK Economy Light Co.. _.. _. __ . ______. ___ Escanaba, Mich. 256 WMAL l\L A. Lesse Optical Co.. .. ______. __ _._\\ ·ashington, D. C. 213 WRAM Lomba,d College ...... _ ...... _ ...... Galesburg, Ill. 244 WMAN First Baptist Church .. _...... :;. .. __ ._ .. _. __ _.. Columbus, Ohio 278 'VRAV Antioch College.._._ .._ .. _.. _.. _ ... __ ... Yellow Springs, Ohio 263 WMAQ Chicago Daily News ... ___ ...... _._._ .._ .. _. ___ ._ .. _Chicago, Ill. 447 'VRAW Horace D. Good. ______._ .. _Reading, Pa. 238 WMA Y Kingshighway Pre::;byterian Church ______St. Louis, Mo. 248 'VRAX Berachah Church .. ". ___ ._ ...___ ._ .._._ .. __ ._.Phiiadelphia, Pa. 268 WMAZ Mercer University_. __ _.. ____ . __ . __ .. _____ .. _.. _.. _.. .lHacon, Ga. 261 WRBC Immanuel Lutheran Church ... __ .. _...... _Valparaiso, Ind. 278 WMBB American Bond & l\.iortgage Co._._ .._ .. _. __ ... Chicago, III. 250 'VRC Radio Corp.· of America______.\Vashington, D. C. 468 WMBC Michigan Broadcasting Co. ______. ___ ._ .._ .. _Detroit, l'VIich. 256 WRCO Wynne Radio Co ...... Raleigh, N. C. 252 WMBF Miama Beach Hote1... _. ______Miama Beach, Fla. 384 'VREC \Vooten's Radio & Electric Co ...... _... Coldwater, Miss. 254 WMBI Moody Bible Institute._. ___ ._ .. _.. _.. _.. _. _____ ....Chicago, Ill. 288 WREO Reo Motor Car Co. _____ ._ .. __ . __ ._ .. _. __ ...... Lansing, Mich. 285 WMC _ Commercial AppeaL..... _... _.. _ .. _.. _. . _.. . Memphis, Tenn. 500 'VRHF Radio Hospital Fund_ .. _._ ..___ __ . ___ . _____ Washington, D. C. 256 WMRJ Peter J. Prinz______._.. __ .. Jamaica, N. Y. 227 WRHM Rosedale Hospital, Inc ..... __ .._ .. _... Minneapolis, MiAn. 252 WMCA Hotel McAlpin(Greenley Sq.Hotei Co.) New York, N.Y 341 'VRK Doron Bros .. __ ._._ ..... __ ._._ ... _.. _.. __ ._ .. _. ___ .. Harniiton, Ohio 270 WNAD Shepard Stores_ .. _.. _. __ .. _.. _. __ .. _.. _.. _.. _.. _Boston, Mass. 280 WRM University of Illinois. ____ ._._.. _... Urbana, Ill. 273 WNAC Shepard Stores_.. _ .. _.. _.. _.. _.. _.. _. __ .. _.. __ .. Boston, Mass. 430 WRMU A. H. G,ebe & Co., Inc.,~1.Y."MU·l" .. New York,N.Y. 236 WNAD University of Oklahoma______._. ______.. _Norman, Okla. 254 'VRNY Experimenter Publishing Co._._.. _ ... __ ._New York, N. Y. 375 WNAL Omaha Central High SchooL._._ .. _.. ____ .. Ornaha, Nebr. 258 WRR Municipal Station_._... _.. _ .. _.. _.. _.. _____ ._ ... Dallas, Tex. 246 WNAT Lenning Bros.Co.(Frederick LenningLPhiladelphia, Pa. 250 \VRST Radiotel l\Hg. Co., Inc. ______. __ . _____ Bay Shore, N. Y. 216 'VNAX Dakota Radio Apparatus Co_ .. _. __ .. ___ ._ Yankton, S. Dak. 244 \VRVA Larus & Brother Co., Inc ...... _.. __ ._ .. _. __ .._Richmond, Va. 256 WNBH New Bedford Hote1 ______.. __ . _____ ._J\ew Bedford, l\"1ass. 248 WSAI United States Playing Card Co .. _.. _... Cincinnati, Ohio 326 WNJ Radio Shop...... _ ... __.. __...... Newark, N. J. 252 WSAJ Grove City College_. _____ ._ .. __ ._ .._ .. _.. _.Grove City, Pa. 229 WNOX Peoples Tel. & Tel. Co... __ .. ______._ ... Knoxville, Tenn. 268 WSAN Allentown Call Publisher Co .. ______. __ . ____ AlIentown, Pa. 229 \VNRC W. B. Nelson. __ ._. __ .._ __ . ___ ._ .. _. . _. __ Greensboro, N. C. 224 WSAR Daughty & \~le lch Electrical Co._ .. _... Fall River, I\:lass. 25t WNYC Dept. of Plant & Structures______. .:\few York, N. Y. 526 WSAU Camp Marien_ .. _. _ ...... _.. __ .. __ ._ .. _.. _._ ...Chesham, N. H. 229 'VOAI Southern Equipment Co._ .... _.. _.. _.. .5an Antonio, Texas 394 'VSAX Zenith Radio Corp. (Portable)_... __ ..__ ._._._ .. Chicago, Ill. 268 WOAN Vaughn Con. of I\"lusic. __ .._ .. __ ._ .. .Lawrenceburg, Tenn. 283 'VSAZ Ch~ Electric Shop_ ..... __ __ . ______Porneroy, Ohio 244

RADIO AGE SUBSCRIPTION BLANK Radio Age, Inc. Use the 500 North Dearborn Street ~50 A YEAR Chicago Log.. a .. Wave Gentlemen: PICIl8e enter my subsC"l"iption for RADIO AGE, the ~Ia gazine @f the Hour. for one year. beginning with the .• __ . ____. __ ._ issue, for which I enclose $2.50. Name ______. __ . ____ ._.____ . ___. _____ ~ . ____._._ ... ____._._._. ___. ______. Chart Street Address ______. __. ___ ._.. __ ._____ . ______. ______. ____---"- City __• ___ ._. __ ..______.. ______. ______. ___ .__ on Page 56 RADIO AGE for October; 1926 The Magazine of the Hour 61 actual attendance is impossible. I A large number of the sta­ tioas not owned or operated by religious bodies have the Sun­ day service in charge of various local churches in rotation, a plan which seems satisfactory to all of them. Well-known hymns are the most popular parts of now,-J the program and many letters are received asking for this or that particular old favorite. In fact, it is the fostering of searching this spirit of broadmindedness and tolerance that several writ­ ers gave as being the great con­ tribution of radio to religion. dial action Stations giving violent and rad- I ical religious expression are I most apt to be tuned out while the service run on the strictly for humanitarian and undenomina­ tional lines, like the Little Brown Church of WLS, offends no one, whatever his belief. J60-degrefJ Audience Size Unknown HE SIZE of radio church T audiences cannot be com­ condensers puted. Most of the stations in EARCHING dial- action and to combine utmost tuning the survey admit frankly they to meet the demands of accuracy with case of control, do not know, while some make c5 congested broadcasting the designers of the qualified estimates of 1,000 up conditions ... to 200,000 but no satisfactory CI\adio Age Super-Wjne -smooth "friction·drive" to means of counting radio audi­ have made it a two-control banish the least suggestion of ences has been determined. receiver, using 360 - degree One feature of growing im­ backlash forever ... condensers, operated by portance in ch urch radio is the collection. This is particularly -these tuning advantages MAR-CO 360-degree vernier dials. significant as it must be purely have made the celebrated voluntary and straight from the MAR-CO vernier dial So justly These dials arc for sale by heart One church writes that popular that 500,000 of them most dealers. They arc su p­ in three years their radio gifts are ill use today. plied in flashing black Bakelite, have reached $8,000 without But these same advanced tun­ with either nickel or gold­ any appeal for funds. The Y. ing features may also be ap­ plated metal finish. The new M. C. A. of one town received MAR-CO 2-inch rheostat dial four hundred dollars in one sea­ plied to the set you build with 360-degree condensers, matches the tuning dials ex­ son, also without any solicita­ actly in appearance. tion. One writer comments that by using the special MAR-CO the man who is not ashamed to 360-degree vernier dials. MARTIN-COPELAND CO. Providence, R.t slip a dime in the collection box In order to secure easier sep­ in church does not hesitate to CHICAGO- Madison Sr. and Wabash Av~. ~ation of crowded stations, NEW YORK-37 Maiden I.anc slip a dollar bill into an envelope in gratitude for some radio serv­ ice which he finds inspiring.

for 360 0 condensers o Please mention Radio Age when writing to advertisers 62 RADIO AGE for October, 1926 The Magazine of the Hour

WSB Atlanta JournaL ______.. ______.Atlanta, Ga. 428 \VTAB Fall River DailyHeraldPublishingCo. Fall River,Mass. 266 WSBC World Battery Co. ______. ______Chicago, Ill. 288 WTAD Robt. E. Compton______Carthage, 111. 236 WSBF Stix-Baer-Fuller D. G. Co. ______.5t. Louis, Mo. 273 WTAG Telegram Pub. Co ...... _...... _... Worcester, rviass. 545 \VSBT South Bend Tribune. ______.SOuth Bend, Ind. 275 WTAL Toledo Radio & Electric Co...... Toledo, Ohio 252 WSDA Seventh Day Adventist Church. ______.New York, N. Y. 263 WTAM \Villiard Storage Battery Co...... Cleveland, Ohio 389 WSKC \Vorld's Star Knitting Co.______.Bay City, 1\.fich. 261 WTAQ C. S. Van Gordon ...... _.. _...... Eau Claire, \Vis ..... 254: WSM Nashville Life & Accident Ins. Co. ____ .Nashville, Tenn. 283 WTAR Reliance Electric Co ...... _...... _...... Norfolk, Va. 261 WSME Saenger Amuse. Co. & Maison B. Co._.NewOrleans, La. 319 \VTAW Agricultural & Mech. Col. of Te;(as.. College Sta., Texas 270 \VSMG Madison Sq. Garden Bdcast Corp ___ _.New York, N. Y. 303 WTAX Williams Hardware Co ...... _...... _.. _...... _... Streator, m. 231 WSMH Shattuck IVI usic House. ______. .Dwosso, 1\:1 ich. 240 WTAZ Thomas J. McGuire...... _ .. _.. _... Lambertville. N. J. 261 WSMK S. M. K. Radio Corp. _____ ._ .. _____ ._. ___ ...... Dayton, Ohio 275 WTIC Travelers Insurance Co ...... _.. _ ..... Hartford. Conn. 476 WSOE School of Engineering..... _.. _.. _.. _.. _... A..filwaukee, Wis. 246 WSRO Radio Company..... _.. _ .... Hamilton, Ohio 252 \V\VAE Electric Park.... . _. _...... _ .. _...... _.. _... Plainfield, Ill. 242 WSSH Tremont Temple Bap. Church .... _.. _.... . Boston, 1-'1ass. 261 \VWGL Radio Engineering Corp. ... _ ...... _.. Richmond Hill, N, Y. 213 WSUI State University of iowa._ .._. __ .. _.. _.... .Iowa City, Iowa 484: \V\VRL \Voodside Radio Labs.. .. _...... _.. _...... Woodside, N. Y. 258 WSVS Seneca Vocational SchooL.._ ...... _... Ruffalo, N. Y. 219 WWJ Detroit News.. _.... _.. _.. _...... _.. _ .. _ ..... Detroit Mich. 353 WSWS illinois Broadcasting Corp.... _ .. _.. _. ___ .. \Vooddale, ill. 275 WWL Loyola University...... _...... _.. _ ...... New Orleans La, 275 Dominion of Canada CFAC Calgary Herald.______Calgary, Alta. 434 CJCL A. COuture ....._ ...... _.. _.. _.. _.. _.. _ .. _.. _ . .IVlontreal, Que, 279 CFCA Toronto Star Pub. & Prtg. Co .. __...... Toronto, Ont. 356 CJGC London Free Press._. __ ...... _.. _.. _ .. _.. _.. _... London, Onto 329 CFCF Marconi \NirelessTeleg. Co., (LH.) Can. Montreal, Que. 411 CKAC La Presse ...... _...... _.. _.. _.. _...... _.. _.. _... MontreaI, Que. 411 CFCH Abitibi Power & Paper Co. (Ltd.) . .IroC/uois Falls, Onto 500 CKCD Vancouver Daily Provincc...... _.. _..... Vancouver, B. C. 397 CFCK Radio Supply Co.... _.. _.. _.. _.. _.. _. . _. . _.. . Edmonton, Alta. 517 CKCK Leader Pub. Co ...... _.. _ ...... _.. ..:. .. __ ._ ...... _... Regina, Sask. 476 CFCN W. W. Grant (Ltd.l ______Calgary, Alta. 434 CKCL Dominion Battery Co.... _.. _.. _.. _ .. _.. _.. _ .. _.. _... Toronto 357 CFCR Laurentide Air Service._ ...... _.. _.. _.. _.. _. .. Sudbury, Onto 410 CKCO Ottawa Radio Association. _____ .... _.. _...... 'Ottawa, Ont .. 434 CFCT Victoria City Temple ...... _...... _.. .Victo ria, B. C. 329 CKCX P. Burns & Co. (Ltd.l ______.Calgary, Alta. 434 CFCU The J ack Elliott (Ltd.l ______,Hamilton,Ont. 341 CKFC First Congregational Church..... _.. _ ... Vancouver, B. C. 411 CFHC Henry Birks & Sons._ .. _.. _...... Calgary, Alta. 434 CKLC \Vilkinson Electric Co. (Ltd. L ..... _.. _..... Calgary, Alta. 434 CFKC Thorold Radio Supply______Thorold, Ont. 248 CKNC Canadian National Carbon Co ...... _.. _.. _... Toronto, Onto 357 CFQC The Electric Shop (Ltd.l ______.Saskatoon, Sask. 329 CKOC 'Wentworth Radio Supply Co .. .. _.. _.. _... Hamiiton, Onto 341 CFRC Quee ns University...... _.. _ .. _.. _.. _.. __...... Kingston, Ont. 450 CKY Manitoba Tel. System._ .. ___ .. _.. _.. _...... \Vinnipeg, Man. 384 CFXC \-Vestminster TruSot Co .... _.. _...... _... \Vc-stminster, S, C. 291 CNRA Canadian National Raihvays... _...... _... Moncton, N. B. 312 CFYC Commercial Radio (Ltd.) ... _.. _ .. _ .. _... Vancouver, 13. C. 411 CNRC Canadian National Raihvays... _.. _.. _.. _... Calgary, Alta. 436 CHBC The Calgary A lberta n ... _.. _. . _.. _.. _.. _.. _ .. ... Calgary. Alta. 434 CNRE Canadian National Railways... _...... _... Edmonton, Alta. 517 CHCM Riley & McCormack (Ltd.l ______Calga ry, Alta. 434 CNRM Canadian National Railways...... _... Montreal, Que. 411 CHCS .The Hamilton Spectator._...... _. . _.. _.. _. . .Ilamilton, Onto 341 CNRO Canadian National Railways...... _... Ottawa, Onto 435 CHIC Northern E lectric Co...... _...... _.. _. . _..... Toronto. Onto 357 CHNC Toronto Radio Research SOCiety._ .. _. . _..... Toronto, Onto 357 CNRR Canadian National Railways...... Regina, Sask. 476 CHUC International Bible Ass'n ..... _.:_.. _ .. _ .. Saskatoon, Sask. 329 CNRS Canadian National Railways...... Saskatoon, Sask. 329 CHXC R. Ilooth, Jr. ______.______Ottawa, Onto 434 CNRT Canadian National Railways ...... Toronto. Ont. 357 ClIYC Northern E lectric CO ...... _.. _.. _.. _ .. _ .. _... l\'Iontreal, Q ue. 411 CNRV Canadian National Railways.__ .. _...... Vancouver, B. C. 291 CJCA Edmonton JournaL __.. _.. _.. _ .. _ .. _.. _. .. Eclmonton, Alta. 511 CNRW Canadian National Railways...... _. __ ... \Vinnipeg, Man. 384 Republic of Mexico CYIl Mexico City______380 I CYI. ~Iexico City______400 I CZE Mexico City______._ •. ______350 Republic of Cuba PWX Cuban Telephone Co, ...... Havana 400 5DW R. S, Calderon ...... _. .. Matanzas 200 6KW F. H. Jones ..._ ...... __ ...... Tuinucu 272 2BY F. \V. Borton ...... _.. _._ ..... Havana 2(,0 6VY Jose Ganduxe._.. _ ...... Cienfuegos 260 7SR S. Rionda ...... Central Elia 350 20K M. G. Ve lez..... _.. _. . _...... Havana 360 / 1 6JK F. H, Jon ~s ...... - .. -..- ... Tuinucu 340 8BY A. Ravelo._ ...... 5antiago de Cuba 250 20L Oscar Collado... _.. _.. _ .. _... Havana 257 Great Britain 2LO London ______365 5XX Daventry. ____ .. _.. _.. __ .. _.. _ .. _.. _... l(,OO 2ZY Manchester.__ ...... _.... _.. _.~_ .._ ... 378

SIT Birmingham... _. . _...... _.. _.. _ .. _... 479 26RB~1 D ublin ______. ______390 5NO Newcastle... _...... _.. _...... _.. _.. _.. _ ... 404 5WA Cardiff______353 1 / 5Se Glascow. __ .. _.. _ .. _.. _.. _.. _...... _.. _ ... 422 1l Bournemouth ..._ .. _ ...... _.. _.. _.. _.~ . 386 2BE BeifasL_ _ .• _._.______440 2ED Aberdeen.__ .._ .. _ .. _.. _.. _ .. _.. _. ___ ... 495 ·1 France I YN Lyons______550 I FL Paris (Eiffel Towerl __ 2,650 1 8A] Paris___ ._. ______1,780 1 ESP Paris ______•______458

Short Wave Phone Broadcasting KC Meter" 2XK Schenectady, N. Y. * 4600 65.16 KDKA Pittsburgh, Pa. * 4760 63.00 KDKA Pittsburgh, Pa. * 5100 58,79 2XAF Schenectady, N. Y. * 9143 32.79 tCrystal ContrOl RADIO AGEfor October, 1926 The Magazine of the Hour 63 ((arbttlell ((onbengerg

YNASTIES have come D and gone. New peo. pIes, new races, new civ· ilizations have flourished and fallen. Through i~ all for over 2,000 years this greatwallhasnoblywith­ stood assaults of man and "You'll make no mistake, madam, the elements. So stands in taking this set. It's a wonder." the Cardwell Condenser "Yes, but see here, how often do -ideals of strength, you have to wind it?" efficiency, craftsmanship. The Taper Plate Type HE" Successful Tests of Radio Weather Maps AlLY weather maps similar D to those you sometimes see in your local post office or li­ brary, are now being transmit­ ted each day by radio from the Arlington station, NAA on 8000 meters. This is the latest appli­ T ype" C" for more cation of the radio picture and lon g wave separation manuscript transmitting and re­ ceiving apparatus invented by C. Francis Jenkins of Washing­ ton about three years ago. Through the cooperation of the Navy Department, the U. S. Weather Bureau at Washington is offering its daily weather map P.RICES: 19 2 E .0005 $ 5.00 173·C to anyone atloat or ashore who 169E .00035 $4. 75 1 71·C 168E .00025 $4.25 170·C has facilities for picking it up. 16 7 E .00015 $4.00 16B.C This map is made up each day by experts of the Washington iEbe !Elllen tao(!Carbl.Uell Weather Bureau from data re­ :fl!1anufacturing (!COrp. 81 ProspedStreet~ Brooklyn, N. Y. ceived by telegraph and radio PadjicCQaJtAgent, BaidwinPacijicCo. • from regional observation bu­ PadjicBldg., San Fmnd!Co reaus. The regular map shows the weather situation for the "THE STANDARD OF COMPARISON" whole United States, but now only the eastern half is being sent out by radio. It is intended specifically for mariners. To - find out how it worked at a dis­ tance, after the first successful Have You R ead local tests, the Navy fitted out the U. S. s. Kittery and Trenton "HOWDY JUDGE"? with Jenkins receivers. To date By GEORGE D. HAY reception on board the Kittery "The Solemn Old j udge" at Norfolk, Va., has been per­ A book o f cha racter stories a ll fIll ed with good fect. Soon one of the Shipping hU!l1or, wri tten on the Memph is levee and in Board vessels will be equipped P oli ce Court _T h e J udge's book is out at la st. J~.! for reception, and it is expected Mu~rvNLUG Mail Or ders are being received by The THli STAND~ON"NECTOk the Weather Bureau will have McQuiddy Press, 110 Seventh. Av~nue North, Nashville, Tennessee. P["lce $1.25 Ask Your Dealer a receiver installed at its Chi­ per copy. L nOWARD B. JONES cago office. 618 S~~a~. Chicago. Ill. Please me ntion Radio Age when writing to advertisers 64 RADIO AGEJor October, 1926 The klagazine oj tlze Hour Ductile Tungsten and Some of Its Uses No Other Metal Has Such I ndustrial Importance By F. C. KELLEY*

T is not my purpose to give transferred to a slab of molyb­ the lead in a pencil. At this stage I you the historical facts con­ denum, tungsten, or some highly it is tough and ductile at room nected with the discovery of refractory material, and refired temperature, and can be bent cold tungsten, and the various chem­ in hydrogen at nearly a white without breaking. The process ical methods of separating it heat for half an hour. This high of reduction to still smaller di­ from its ores, for space does not temperature sinters the metal so ameters is accomplished by draw­ permit. I simply wish to convey the bar can be handled without ing through diamond dies. The some idea of the method used to breakage. It is next clampec1. be­ wire is drawn at a dull red heat produce it in its ductile form, and tween two water-cooled clamps in at first by heating in a gas fur­ its application to the radio indus­ a metal treating bottle, and a nace as before, but as it becomes try. . heavy current is passed through smaller the heat is gradually re­ Although little use had been it. This heats the bar to a daz­ duced, so that it will not burn made of this metal up until the zling white heat, and causes it to the fine wire. The amount of re­ time it was obtained in its ductile sinter still more. It is now duction for each pass through form, it was by no means rare. strong, but not ductile, and a the die also becomes less as the Deposits of its ores occur in many sharp blow with a hammer will size decreases. By this method, parts of the world, and especially break it. The bar may now be wire five ten thousandths of an in the United States, Portugal, rolled into sheets or hammered inch in diameter, or smaller, can British India and South America. into rods or wire by means of be drawn. The' chief ones are wolframite, swaging machines. The process If the desired form of the metal and iron and manganese tung­ depends upon the use to which should not be wire, the highly sin­ state, sheelite, a calcium tung­ the metal is to be put. The treat­ tered bars are rolled hot, just as state, and stolzite, a lead tung­ ment is as follows. The bar is they were when swaged. Metal state. heated in a hydrogen electric re­ sheets rolled in this manner fur­ The pure oxide of tungsten is sistance furnace to nearly a white nish the material from which a obtained from the ore by chem­ heat. It is then pulled out of the variety of products are made. ical separation. It is canary yel­ furnace by means of tongs and The method of making ductile low in color and in its finely di­ inserted quickly into the swag­ tungsten is very different from vided state resembles flour. This ing machine. It is immediately the processes used to produce yellow powder is loaded into withdrawn and reheated. This other metal. It is never melted porcelain tubes, electric resistance time the opposite end is inserted in any part of the process like furnaces, through which hydro­ into the swager. A smaller set iron, copper, nickel, etc., but is gen is passed. The temperature of dies are now put into the ma­ made by pressing finely divided and flow of hydrogen gas are chine for the next operation. powder and heating to a tempera­ carefully regulated for upon This heating, hammering, and ture several hundred degrees be­ these conditions depend the char­ gradual reduction in the size of low the melting point. During acter of the reduced metal. The the dies continues until the bar sintering at such a high tempera­ furnace is heated gradually to a is worked down into wire. The ture the individual particles grow bright yellow heat, causing hy­ bar is not allowed to become cold together forming grains. The drogen to combine with the oxy­ during the swaging operation, bar then actually develops a crys­ gen of tungstic oxide forming because it would break up. The talline structure which may be water which vaporizes leaving temperature of working, how­ seen with the naked eye if it is the pure uncrystalline metal be­ ever, is gradually decreased with broken. The size of the grains hind. its size. When the bar has been The hydrogen-reduced metal worked down into a long wire, depends upon the temperature, powder is next pressed in a mold it is fed automatically through time, etc., of heating. The grains under hydraulic pressure in the the machine by rolls, being heated of a sintered bar when worked form of bars. If a bar is handled by a gas flame just before it goes hot into wire are elongated, giv­ at this stage, it will break under into the swager. It is reduced ing it a fibrous structure. If the its own weight, so it is carefully in this way until the diameter wire is then reheated to a high

·Research Laboratory. General Electric Co. becomes about one half that of temperature the fibers undergo a RADIO AGE for October, 1926 The Ivfagazine of the HOllr 6S RAYTHEON ANNOUNCES Light Socket Power for Filament and Plate for Type 199 Tubes Now Practical FOUR years ago the scientists in the Raytheon Labw The new tube has been rated 200 volts output. This - oratory tackled the problem of using alternating is just what has been needed for the new power ampli­ current as a supply for radio power. After three fiers using the UX-171, the latest development in qual­ years of research the well-known Raytheon, Type E, ity reproduction for the home. This unit will also be described in articles by radio authorities, and complete was developed. In the one short year since this tube factory-built B-power units of this type are now was introduced the B-power market has been revolu­ available at radio dealers for those who require the tionized, and the Raytheon equipped B-power units extra power. today are unquestionably the leaders in quality. One last word on Reliability to those who are not Raytheon, Type B, the 60 milliampere tube, remains already familiar with Raytheon and the Raytheon the standard for regular B-power service. policy. Complete power units, equipped with Ray­ Now these same engineers have perfected the next theon tubes, are manufactured by Companies selected logical step toward a. c. operation-a new and ex­ for their excellent engineering and production facil­ ceptional rectifier for a new and exceptional service. ities. No others are authorized to sell Raytheon rec­ Raytheon, Type BH, has a rated capacity of 85 mil~ tifiers or to use the trademark word RAYTHEON. liamperes, more than enough to supply the 60 mil1iam~ Hence, by making certain that you are purchasing a pere current for the filaments of Type 199 receiving genuine Raytheon unit you are not only assured of tubes connected in series. Here is a wonderful oppor~ the utmost in reliable rectification, but also that the tunity for the home constructor to obtain complete unit has been carefully designed for the service for a. c. operation. Think of it, both A and B power from which it is intended. You will find a var iety of prices a single rectifier! Leading radio magazines will carry and styles to meet every requirement. detailed information on how this may be accomplished. Raytheon is the Heart of Reliable Radio Power. RA YTHEON MANUFACTURING COMPANY CAMBRIDGE, MASSACHUSETTS change and form new equiaxed lamp filaments and cathodes for grains. radio and x-ray tubes. These TRANSMITTING Ductile tungsten is too hard have proved to be its most im­ and tough to be machined with portant uses. It is also exten­ APPARATUS tools, so other methods are used sively used "in the electrical in­ dustry as a contact material In addition to our regular to obtain it in the desired form. broadcast apparatus we Discs are punched from hot where electrical circuits have to be made and broken frequently, carry a very good stock of sheets, and various other forms transformers, chokes, grid are made by forging the hot sin­ as in magnetos, distributors of a utomobiles, and voltage regu­ leaks, high test condensers, tered bars. Heavy sheets may etc., for transmitting pur­ also be sheared while hot to get lators. A very valuable use has been made of it as a target in poses. the required shape. \Ve will shortly issue our The high melting point, tensile x-ray tubes. Phonograph needles are also produced with a tungsten new catalog and we quote strength, low vapor pressure, un­ discounts to dealers or set der the best vacuum conditions, point. Its use as a heating unit in the tube form, and as a heater­ builders who can give satis­ and some other qualities, make factory buying references. it a very desirable metal for winding, has been of very great value in electric furnaces, where Please address us on your the metal is protected from oxi­ regular letterhead. dation at high temperatures by "Outsell, Because They Excel" CHICAGO RADIO a vacuum or an atmosphere of APPARATUS COMPANY hydrogen. A temperature of 415 South Dearborn St., 2500°C can be obtained in a few Chicago minutes in the tungsten tube fur­ CHI-RAD ~ ~~l~d~;~E~ nace, while in the resistance type, ".'J\j l UI".r' ~f DetectmHigh MU(EX-200A) and the temperature is limited only by :.. ~ Power Amplifier fJ. !.. the melting point of the refrac­ BUILD THE NEW SHIELDED If&- ~ " Ask for Folder "L" ~ Dl'aiers and Jobbers tory material upon which it is ~ Write for Prices wound. C::SmpJ~ EMPIRE ELECTRICAL xli- . PRODUCTS COMPANY I Tungsten has also taken a RECEIVER Sales Office,J32·J34 Greene St., New York 11.11;0 Mfu. of EmpIre Cone antI prominent place in the field of I Send 25c '0' con"'"CliM book Horn Spellkers Hamrnarlund-Roberls 1I82-D Broadway, New YOlk Lahoratories & Faclory-}{earny. N. J. (Please tUTn to page 66) L-______--' Ple

lIoo/d et of l1aluable inform(J.~ion anll YOU CAN GET form for 1'roperly d isclosing your Greater re flex: (\r crystal idea frel! on re(/u est. Write today. set reception if you use Now is the time to 'h, RICHARD B. OWEN, Patent Lawyer Subscribe to Radio Age. BROWNLIE 81 Owen Bldg., Washington, D. C. VERNIER DETECTOR 41-M Park Row, N. Y. City $2.50 per year. $2.00 at Your Deale ... or Direct. ROLAND BROWNLIE & CO. 21 Sande ... s St. Medfo... d, Mass. flc,!8f} 1/I. e1?- tfu~. R!l!Iiu A[lo w hen writing to adv ert i-SOT8 RADIO AGEJor October, 1926 The Magazine oj tlze Hom 67

the time of day, and radio trans- I r;:-======-----=====--======~ mission. Much is being accom­ plished with the cooperation of We Carry a COlnplete Line of Parts the amateur operators in all parts of the world. Operating sched­ for the Following Circuits: ules of Station lXV and cards upon which data may be for­ warded to the station have been sent to all interested amateurs. RADIO AGE SUPER 9 Experiments have revealed that signals are more or less regu­ St. James Madison Moore lar when the sky is clear, but Qualitone Samson 7C weaken or entirely disappear I Short Wave Victoreen when certain conditions of cloudi­ ness are encountered. A wide­ Browning-Drake Universal spread area of rain which in­ Hammerlund Roberts Aerodyne c! udes both transmitter and re­ ceiver has generally been found Orders shipped sam.e day received to give better signals than those obtained in clear weather. WHOLESALE RETAIL It has been found that for short wave transmission to a fixed re­ ceiving station there is a mini­ mum wave-length beyond which NEWARK ELECTRIC Co. signals disappear entirely at the ./rOflti.!!:!I huf ~aclio" receiving station. The wave­ length at which the signals dis­ 226 WEST MADISON STll.E£T appear is called the "cut-off" TEl-EPHONF., wave-length. In transmission I MAIN 4627 over a distance of 75 miles, for example, the "cut-off" wave­ length varies between 32 and 50 !.!.,;;;::;;;:::...,.=.....;;;;;::...;...... ;;;;;;::;;;::::::::::::::::::::::~§'..;...==.....;;;;;::;;;::;;;::;;;::;;;::;;;::;;;::;;;:::gJ meters for various times of the ---- ~~ ­ day. Commencing soon after nals over short distances, but noon the "cut-off" wave-length rises rather rapidly after sunset is smallest throughout the after- until the maximum value of about noon, which is considered the best 50 meters is reached soon after time of day for short-wave sig- midnight. From that hour until noon it decreases slowly and fairly r egularly except for slight variations at sun-rise. It again reaches its lowest value of about 32 meters shortly after noon. Tests are also being made with CONDENSERS many types of antennre for fol' your R.adio set or your short-wave transmission. These B-Eliminator, your condenser vary from a small antenna problem is a problem no longer. Sh h mounted entirely within the sta- D:lu':e~ ::a~i~g-'e~:~~::!ty~i;:::,::~~n,,;ore tion to a large exterior structure Tobe Deutschmann Co. Science has discovered a new principle more than 100 feet in the air. Engjn~T:/h~t:/P~:~:~~:rer.FOJ in radio amplification . . . a striking new development that is bringing un- One of the most remarkable fea- Cambridgep dJau. heard of results. This principle is found- tures of th~ short wave research _-~ ______-=--- edBalloon upon Circloid.a new kindI t ofbrings coil-the 4 dist Erlainct IS. tha t'sIgna I s may b e sen t great WANTED : RADIO EXPERTS improvements. These are explained in a distances without a large antenna $60 to $100 A WEEK TO START! ~!~l~d~ir~~.bookjust published and being structure. Communication be- ~1:~Jf':~~~~er~,en d~~~ib~~~;;,.ra~~~l:::. wbrnot:j: Edition limited-Write today tween Station lXV and various ~:i:~ie~ ;!iJ~oB;igh:f~t~~:f:t~~i~ fu~t~gr:~~ Get this book and read about this stations in Europe, Australia and ~UR~N(hNEERS WILL TRAIN YOU newest scientific radio principle. See the South America has been carried Now is the time to make the big money in ndio. We many different circuits in which it may on regularly on an antenna sys- ~~~~I t~~~s i· ol~ fro:d:~IO~ ~ :;;;S a';/~~~i(l': i:~~tO~'it~i:e~~~~ be used. Find out how you can turn your present set into the latest example tern consisting of only tw·o wires \YE'GIV~nTRAINED MEN POSITIONS of radio engineering-and at a remark­ slightly more than 20 feet long !~dg~'"te I~:~ ~~y~ u- ~~~n ~l a~a

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SELL MARVELOUS NEW RADIO INVENTI.ON THAT ;:?:.~ 1~~eam&'i:~dteMI;(o'J/W'!.i~e~"d:~t~r W~::elt,.~~cti~ 3 e l"ment Rectifi"r j .... 8 for a eliminator., a battery IMPROVES lumm er reception 100 ')'< . Elfarece marvel Cono"er (Compoter), AVON, New Jeney. charter. and tr.. n8mittW'I, 1 jar takea the place of 2 i;:!d:ta~I~~ns:ileg!:e!v~~t~~Ji:.n~~~:~e~~~ :~i:t~:~~: ==~==~=~==~===~- ~~~~~:rtij~di;,!i~::{4;J9i!:td~udia~~n;~n$I~'or~~~~ Wrile lodey. Filhwick Radio Co., 1.15 Centrel Perkway. PERSONAL 4 for $3.00, prepaid to 5th :zone, 1/2 ca"h with order We.t, Cincinnati. Ohio. balance C. O. D. Sati"faction or money back. George LONELY HEARTS, E"chant.. r.. tteu; make intere.tinr Schub, Calumet, Mich.

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A neW cin:uit juet out, .omething dilferent. Send 2 Agente Wantod VANCY Cu .. r .. nteed Radio Tube. with cent ah.mp for inlormation how to build your own let. imported filament .. II typu BEST BY TEST .. leo t ran._ Web R"dio Company, Bo. 849, Chicago, III. mitte,.. Sample tubel $1,50 ea"h POll Paid. Send :~":v~G~:~~i{i:s~·I.~N~ ~~eef-Deforelt Radio Com-

$50 WEEKLY EVENINCS, DEMONSTRATING auper 4000 ohm N &. K He"d Phonea, nn.,.t end mod een.itive .electl.. e 6-tube radio let. Selectrodyne R"dio Co., Phone. out, Iiet $8.50 ",ell lor $6.25 while th.,y I .. ,t, pre_ Dept. M-325 Welt State, Rockford, IIlinoil. peid c.lh with order, .b.olute .ati,f.ction or money ArrENT,ON SET BUILDERS: Increale efnciency and b .. ck. Geo. Schulz. C.lumet, Michill.n . .electivity by inltalUnl[ e eet of binocul ..r type r adiofre_ quency coill. Set Builde... u ee e.ten,i"ely. Set of three AUTOMOBILES $6.45. MoneY-lavinl' pr\c:a lbt mailed upon requelt. , NO MORE BATTERIES. Yo ... un eJiminat. all bat­ All artidel .old on money back gua,,,nte e. Midw",t t.,.rl", and o~er ..te your eet On liaht current, AC or Ult'ht' weig ht ALOY-NUM ~ilton. for aU ca,. and Redio Supply. De~t . C., Box 222, Recine, Wi.conein. DC-no hum-any kind of .ct-any type of tub",. truckl, low price .. , get circular. Egge, 7704 South Main Com~lete blue ~rinh .. nd in.truction., gu .. ranteed Street, Lol Angelel, California. $2. Enllineer.' Ser"i"e Com~ny, Suite 203, 15 Park Row, New York. BOOKS AND MAGAZINES YOur .eri.. 1 i. only •• I'ood a. your in .... lato,.. The t ;:tf:°:!ty TROUBLE-SHOOTlNC- Do it yourself. Juet off the f!:k~~: ;J.,"':rch.~lr~~ ~7~oJa:~; ..~d":o "4:: zone, 2c e .. ch extra beyond. C.eh with order. satil_ ~re u. p ege booklet tell. how to loc.. te and Sent prepaid On factton Or money back. Ceo. Schulz, C.lumet, Michi_ clear ; What to .Do When Sct Goel Wrong; gan. How ten by natIOnally "nown a uthorltie., r 48 p"ge "atalog of "." ealer for, "PRACTICAL GUIDE FOR latelt .. n e.t pr.. cti"al, aeientinc, mech.. nic: .. I.nd In_ EVER OWNER AND au ILDER," or .ond 10c du"tri.. 1 book.. Midl.. nd f>1.od ... cta Co., Dept. RA, 524 today to Uni"en.. 1 Telt Equipment Co., 2939 N. Oakley Courtland St., P.rk Ridto, Illinoi • . A real DX Circ:uitl 5 tube. O"er 3000 milee r.nlle with A ..e., C hicaro . Illinoi•• loud ",pe.. kor "olume. Send $1.00 for circuit and in_ .truction •• Tuttle R.dio Labor.torl.... Diamond, Ohio. SILICON Tren,former Steel cut to order .014". 10 n••. 25 cent., 5 lb.. 30 cenU, leu th"n 5 lb.. 35 cent. per lb., 4 cubic: inches to the lb•. 007" for radio frequency trane­ SAVE MONEY on radio letl and parh. Lilt free. All ~~~ A~~~r:~~~:r-:~!Tn:riefl!~j;!r~e." is;:~~~i~! formen. SOc cubic inch, po.tage extra. At lea.t 1/2 merch .. ndi.e gu ..r ..nteed. GEMRAD COMPANY, 631 ca.h with order-belance C. O. D. Geo. Sc:hui:z, Calu­ E. Okmulgee, Mu.kogee, Okla. Twentieth Century Book of Receipt., Formul •• and met, Michigan. ~ roc e. . 10,000 pro"en manufacturer. work. hop, Bekelite lubp.. nele with 6vo built in X type eockeh, "$1.00 For Your Old Tube. regardle .. 01 m ..ke or con_ I .. bora • Scnt pre p .. id upon r e ceipt connection. m a rkod liz. 7123, five dollers by mail dition toward .. the purch •• e of e .. "h new Standard 48 p .. ge "ataloll oflate.t ..nd order. Subpanel bra"kete ••even inche. long, two and $2.50 tube. Poaiti"oly Ilu ..ranteed., We do not eell e"hanic,,1 and induetr;"'1 half inchel high, one doll .. r a .et. Sati.faction I'uer_ rebuilt Or bootleg tube•• Ordor tocl .. y. L ...... m & Da"i. book.. Midl"nd Producte Co., De pt. RA, 524 Courtlend anteed or money r

BUSINESS OPPORTUNITIES 20lA .nd 199 tube. reju"enated 30<:. Charlel Bloedorn. ?e~~~~{:~~;r;:~:.:~h~~r~4rH!r~i!~~7~!:~:z;~;r~Z:~t~: 1394 Detroit Street, Den".r, Colorado. e le mente 3 1-2" lonl' 15c, 7 lor $1.00 .. II with br .... ter_ minah, prep.. id to 5 ~One. No o~der Ie.. th.. n $1.00. Ceo. Schulz, C .. lumet. Michil'an. SALESMEN WANTED Dr.. ftlnl!', Ellpert Commercial, Architectural, Licenae d, CRYSTALS-NOT GALENA Rea.onable. Union S e rvice, Liberty, Indiana. CELERUNDUM- th. mOlt .en.itive cry.tal rectifier M ..ke $100 WEEKLY in .p.. re tlmo. Sell wh.. t the In the world. It i. non_motallic .enllitive a ll o"er; low pub);c w .. nh- Iong dietance radio receiving leb. Two re.ietanco; I'reater " olume. Will not burn out. Twelve CODE c ry. tah lor $1.00 ~Olt paid. ~~e:a;~::~It.pa~ha~~~O orC:I~raJ'o° m~~e i$9"5e5Ii';;~~t; D e-Tox-It-A truly great fillod detector-Politi". con. month. Repreeentati"", wanted et once. Thi. pl"n tact-Thoueandl In 1.'1 10. The beet rectifier for CrYltal Set.. Reflex T R Frequen"y and Super Heh 3 for $2.00 ~~u~~;er.i~!n:.heOZ:;'~'UZINC~~~3~O;:~1..J:.~~rA,,:,~~ POetp.. id. Chic:ato. WE HAVE A BOOK THAT TALKS .. nd linge, pl"YI the pi .. no .. nd telle etoriee. In.ide .. ttr.. cti".. co"er. i. " eomp .."t, pra"tlc.. 1 and complete r .. dio outfit. No operAtinl' e.pen ee; no batterlee or tube. to replace. CRYSTALS E"erythinl' il incl ... ded-{cry.tal .et aeri ..1 and I'round STAMPS lea d. indoor .. ntenn .. and p ..ir of phone.) . Tho Talk­ S upe,.en.;ti ..e C .. lena Cry.tel.: Pound 75c prep.ld. ing Book, $5.00 comple t . co nnect it in a Iec.ond and it ALKEMITE. All .en.iti"e CrYllah 50<:. Bu.kett, Iloe. for a life tim.e. No ovorhead. E. W. Pitt Com­ 69.tampI, 4 "enta. Book Stamp Company, 642 Mered.ith C eololliat, Joplin, Mi ..ouri. pany, 115 Federal St., Bo.ton , M ..... Street, D .. yton, Ohio.

Rad io Age Classified Ads Bring Results

Please mention Radio Age when writing to advtrtisCTS Dealers who sell the Majestic "B" Current Supply are confident that it improves recep­ tion. So confident, they make you this unus­ ual offer: Buy a Majestic today. Attach it to your set and use it for one week right in your O'wn home. If, at the end of this time, you are not fully convinced that it gives you better radio performance -more dependable power at less cost-your money will be refunded! Economical to Operate You couldn't want a better proposition than this. The Majestic"B"Current supply, because of its ul'varying constant voltage, gives you improved tone, greater vol­ ume-all at the low cost of All the h-fajestic uB" Current about one-tenth cent an Supply units are manufac­ turedcomplete inourfactory hour. So you can appreciate andare equipped with the fa .. that here is a practical radio mous Raytheon Tube. (En­ dorsed by numerous radio investment. engineers and editors) which is a non-filament tube with full wave rectification, no Your original purchase price will be returned acids or back surge. Tests of through operating economy alone. the Majestic "B't ontheoscil... lographdemonstrate that all A-C hum is eliminated. Majestic Standard-B Majestic"B"CurrentSuJPPly Especiall V adapted for sets delivers direct current, your socket having not more than seven pure from light 201-A tubes, or six 201 .. A plus one 135-150volt power Give that set of yours the power it needs-power for tube. Popularly priced for the average set. Improves any variation in tone. Then you'll have a new a ppre­ tone-betters reception. dation of radio. You will have one delightful program Price ••••••••• $32.50 WestofRockv Mts.•. $35.00 after another-summer evenings-winter evenings -ALL the time! Majestic Super-B Capacity 1 to 12 tubes, in.. That's when your set is equipped with Majestic "B" cluding the use of 135 .. 150 volt power tubes. Complete Current Supply. Your set seems Alive with marvel­ with switch to control cur.. ous energy. You sense a new joy in radio. rent from light socket. Price ••••••••• $35.00 You at last forget its ll1echanics, for a simple switch releases West of RockV Mts••• $37.50 all the power you need for any program. Power-clean_ Majestic Master-B constant-abundant! Power that instandy responds to high Rating 60 mils at 150 volts. Particularly adapted for soprano, and as easily brings you the full resonance of an Radiola 25, 28 and 30 and orchestration! Easily attached to your light socket saving Super heterodynes. Will you constant bother and attention. operate all power tubes, also the new super-power tube UX.171 (180 volts). Un. SEE YOUR DEALER equalled for sets having a FOR DEMONSTRATION very heavy current draw.. Price ...... $42.50 West of Rocky Mrs. •• $45.00 Grigsby-Grunow-Hinds CO. 4586 Armitage Avenue Chicago, Illinois CUlith 100% Reserve Power eNew and Improved FRE S HM4 M1ASTERPIEClE "TREAR(STOKRAT A one-piece Console of finely selected Genuine 0\l[aho9f:"ny One of the finest pieces of furniture in which a radio"receiving set has ever been installed. It is truly an aristocrat with its dlstinctive. finely proportioned lines and rich I ustrous finish. Equipped 'With the finest of COWiE SPEAKERS especially designed to bring forth the full merit of the newoonstruction of the Freshman Master~ piece circuit. Designed for the employment of the new UX·112 Radiotron Power Tube and the necessary "C" battery connect~on-anmetal SHIELDED hont and ,ub-paneI. Sold on easy terms by Authorized F r eshman Dealers. who also inst all and service them

C II ~S . FRESHMA.N Co., INIl~ FR]!;SJIoMAN BUILDING. NEW YOIUC. 262(; W. Washington Blvd., Chicago GENUINE RCA RADIOTRONS are shipped 'With Freshman Masterpiece Receivt"rs - m atched ·and tested ,"or each individual set~ Price with this equip· Write for our beautiful new booklet il1ustr.lli_n~ , ment (one UX 112 Power Tube; one UX 200A. $ ..... , and describing our 1927 Receivers and A.::cessones Detector Tube; three UX 201A AmpliVylng Tubes) .&& WDrlds Greatest Radio, • iii' Scanned from the collections of The Library of Congress

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