THE NATIONAL RADIO EXHIBITION

R FICIAL CATALOGUE 0D

Je Histone v/d Radii J3IBLI0THEEK N.V.H.R.

f We differ - but never over

Britain's best radio"

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Complete with one Additional valve valve p a'n el for panel for American English halves 11 Gns. halves: 2 Gns. Deferred Terms if desired.

md icates condition p of valves by a

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Write for pamphlet giving full details. THE AUTOMATIC COIL WINDER & ELECTRICAL EQUIPMENT CO., LTD., Winder House, Douglas Street, London, S.W.I. Telephone: Victoria 340417. I I A » I G>

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2 ! I OFFICIAL CATALOGUE

TNI NATIONAL RADIO EXHIBITION

BlBLIOTHEEK N.V.H. ff,'

AUG 25-SEPT 4

ORGANISED BY THE'RADIO MANUFACTURERS' ASSOCIATION, ASTOR HOUSE, ALDWYCH, LONDON, W.C.2. »■»

TESTING INSTRUMENTS Raqd Trade Mori

^•:n :•? V . ' STANDS Nos.

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Simplifies valve testing. Enables all valves to be tested under actual & working conditions without the need for cutting connections and grovelling about inside the set. Instantly adapt­ able for 4-pin, 5-pin and 7-pin valves. Complete as illustrated. */S. 9-PIN AVOCOUPLER aSBSSdJTiftSE 12/6 valves. The UNIVERSAL AVOMINOR A compact precision moving-coil instrument pro­ viding facilities for A.C. and D.C. testing. A total of 22 ranges cover A.C. volts, D.C. volts, current Descriptive, pamphlets post free on request. and resistance. The 3-in. scale is accurately cali­ brated. All readings direct. Total resistance of meter THE AUTOMATIC COIL WINDER & is 200,000 ohms—ensuring accurate readings. Com­ . plete with leads, testing prods, ELECTRICAL EQUIPMENT CO., LTD. i crododile clips and instruction £5 10s. Winder House, Douglas Street, London, S.W.I i booklet. : Leather Carrying Case, I Os. Telephone: Victoria 340417. :

4

_____ I CONTENTS.

Page A Message from The Rt. Hon. Lord Gainford, P.C., Presidentof The Radio Manufacturers' Association... 6

To Our Visitors—Mr. M. M. Macqueen, Chairman of The Radio Manufacturers' Association and Chairman of the Exhibitions Committee 7

Plans of Stands— Ground Floor, Grand and National Halls ...... 8-9 Gallery, Grand Hall...... 10 A Message from the B.B.C.—Sir J. C. W. Reith, G.B.E...... 11 Index to Exhibitors...... 13-15 Index to Telephone Numbers of Stands, etc...... 17 Broadcasting Stations : Their Characteristics and Times of Transmission...... '.. 18-25 British Stations...... 18 European Stations ...... 19-22 Short Wave Stations...... 23-25

Official Appointments ...... 27

General Notices ...... 29

Particulars of Exhibits ...... 30-153 Stands on Ground Floor (Grand Hall)—Stands 1 to 105 ... 30-118 Stands in Gallery (Grand Hall) ...... 119-145 Manufacturers’ Suppliers’ Section (Stands 150 to 159) ... 119-123 Instrument Section (Stands 160 to 168) ...... 125-129 General (Stands 201 to 222)...... 131-137 Trade Section (Stands T1 to T20)...... 139-145 The Radiolympia Theatre (National Hall)...... 146-147 Television Demonstrations (National Hall) ...... 148-149 Radiolympia Museum (Stand 212, Grand Hall, Gallery) ... 151 G.P.O. Exhibit, Radio Interference (Stand 98, Grand Hall, Ground Floor) 153 'Description of Speech-Amplifying Equipment for the Theatre and for Programme Diffusion to Exhibitors’ Stands ...... 155-158 Classified Directory of Exhibits ...... 159-165 List of Members of The Radio Manufacturers’ Association 167-169 Index to Advertisers 171 Officers of The Radio Manufacturers’ Association ... 172

N.B.—The greatest care has been taken in the compilation of this Catalogue, but the Organisers do not accept any responsibility for alterations> ottiissions or errors. 5 A Message from

The Rt.-Hon. Lord Gainford, P.C.

President of The Radio Manufacturevs* Association.

O the late Marchese Marconi we T all owe a great debt. He worked to establish connecting links by wire­ less throughout the world, and it is for the world to see that his marvellous inventions should be utilised to develop not only the radio industry but the blessings of peace. Personally I have been devoted to the B.B.C. because its aim was to enable peoples and nations to under­ stand each other’s standpoints, and to establish a new and ever-increasing employment. So it is a great satisfaction to me to note that the development of broad­ casting and wireless reception proceeds without slackening, and the year which separates Radiolympia 1937 from its predecessor has been as full of achieve­ ment as any before. Each of the main events of the year illustrates the close connection between the progress of the radio industry and of the B.B.C. The Charter of the B.B.C. was renewed in January, 1937, and in the same month the eight millionth wire­ less licence was taken out. This widespread use of wireless may well be attributed to the successful conduct of broadcasting by the B.B.C. as a public utility service, and there can be no doubt that the manufacturers in The Rt.-Hon. Lord Gainford, P.C. the home market have benefited in consequence. The new transmitters at Daventry enabled the broadcasts of the Coronation ceremonies to take a place in history by themselves. The interest created by these broadcasts abroad has probably never been equalled. The goodwill created by achievements of this kind in broadcasting can and should be exploited by manufacturers in the export market. At Radiolympia last year television receivers, suitable for the reception of the new high definition television service, were shown for the first time. This year receivers have the added attractions of technical improvement and reduced prices. The successful daily transmissions from Alexandra Palace have shown that television in the home is no longer a matter for conjecture, but is already one of fact. On May 12th private viewers were able to see the whole Coronation procession pass, and every day brings to them programmes of wide variety. Here, then, is another opening for the enterprise of manufacturers. Great opportunities are being made for the radio industry. May I hope it will take them with vigour and initiative ?

President of The Radio Manufacturers' Association. 6 To Our Visitors

By Mr. M. M. Macqueen

Chairman of The Radio Manufacturers5 Association.

'"THE important part 1 which broadcasting plays in National life is re­ flected in the high public interest which has been dis­ played in the National Radio Exhibitions promoted by The Radio Manufacturers’ Asso­ ciation. Radiolympia 1937 will more than maintain this in­ terest because British radio engineers have again pro­ vided material improvements in broadcast-receiving apparatus. Such is the simple state­ ment, but behind it lies much endeavour and costly research in the scientific fields of electronics and acoustics. This research work is the backbone of the British Radio Industry. These new developments cover a wide field of applica­ tion, but emphasis might be given to the improvements in Short Wave reception. The public appreciation of the widening of entertain­ ment and interest to be obtained by this means is particularly well catered for. This will also be of special r > o ’i Mr. M. M. Macqueen. interest to Overseas buyers, and the wide variety of short wave receivers shown will command a rapid increase in export sales. The '.first public demonstration of Television in this Country was made at Radiolympia irn 1936,'-and the progress in this complementary field to sound broadcasting will form a big attraction to visitors. The Radiolympia Theatre gives a unique opportunity for the public to come into personal contact with their favourite broadcast artistes. A visit to this theatre will provide entertainment of the highest standard. My Association is glad to acknowledge the valuable co-operation which the B.B.C. has extended, and particularly for the special Television broadcasts which they have arranged. May I, as Chairman of The Radio Manufacturers’ Association, express the hope that all our visitors will find Radiolympia 1937 both instructive and entertaining.

Chairman, The Radio Manufacturers’ Association. Chairman, Exhibitions Committee. 7 ------GRAN I

EXIT EXIT l-'fflT* 13 Dm l2.0|2.ll fz?3 37 G[ ii 51 52 5!

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GROUND FLOOR PLAN

The Index to Exhibitors will be found on pages 13 and 15.

The Plan of the Stands in the Grand Hall Gallery is on page 10.

■ A numerical list of Stands, with particulars of Exhibits, will be found on pages 30 to 145.

For particulars of the Radiolympia Theatre see page 146; for the Television Demonstrations see page 148; for the Radiolympia Museum (Stand 212), see page 151; and for the G.P.O. Exhibit of Electrical Interference (Stand 98), see page 153.

A Classified Directory of Exhibits is included on pages 159 to 165.

8 ’

L___ /

HALL

EXIT GENTLEMENS LADIES LYONS LAVATORY LAVATORY EXIT _ EXIT PILLAR HALL • SS ROOMS J2 10 9 7 6 5 4 L ■■ 8 L7 iCLOAK Y ROOM 124| 25 [ | 26 | | 27 [281 [29] [301 LYONS 3 35 34 33 32 H OLYMPIA 2 CAFE 56 57 58 5960 QF^l I ROAD

ENTRAN 69 70 104 enquiry! OFFICE I 71 U

75 73 72 103 l L LYONS 82 83 85 H 87 GRILL ROO M ] 190|891 I 88 I

LYONS r.rTo POST MCRSHI LYONS THEATRE TO GRAND )F«* ROAO ’"iii1011 800KINC H ALL i GENTLEMENS pircJ OFFICE THEATRE ;y LAVATORY PRQCRANMI Er—

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NATIONAL HALL

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HACH successive Radiolympia marks the passage of a year in the history C of broadcasting. The past year has had its share of important broad­ casting events. The total number of wireless licences passed the eight million mark. Following the installation of new short-wave transmitters at Daventry, the Coronation broadcasts were probably heard by a greater number of people throughout the world than any previous broadcasts in the history of wireless. The B.B.C.’s Television Station, inaugurated in November, gives what is at present the only daily service in the world for private owners of television sets. The B.B.C. and the radio industry are partners, upon whose joint success the achievements of British broadcasting depend. Achievements no less remarkable than those of this year can be secured by their continued co-opera­ tion, and the B.B.C. hopes that a propitious beginning will be made with the fullest possible success of Radiolympia, 1937.

3

11

TheseJmen ■ A WHO GUIDE THE CHOICE DF MILLIONS

are wholeheartedly V enthusiastic about K.B. RADIO r*&_y

THE DEALER: "Wc have sold K.B. Receivers for many years and have always been delighted with their THE TECHNICIAN : performance, but we must “ It is always as well to acknowledge these 1938 know that the Receiver • models as your masterpieces. you buy is as technically In design of cabinet, simpli­ perfect as modern radio city of controls and auality practice knows how to of tone they surpass all pre­ make it. I have found vious models.”— K.B. Receivers to be From a Camberley Dealer. designed and built to an exceptionally high de­ THE CRITIC: “That it is now possible to enjoy gree of technical and the world range of an all-wavcr at very moderate scientific accuracy.” — prices is shown by the new K.B. Receivers . . . From a Member of the and it may be said that these K.B. Receivers are Institute of Radio En­ as efficient ether-searchers as you will find in gineers. the world of-radio to-day.”—From the Radio Critic of a leading National Morning Newspaper.

K.B. prefer to leave the praising of their Receivers to impartial experts. But even with qualified judges so unanimous in their opinion of K.B. Receivers ... it is your valuation of their merits which really matters. Come to the K.B. Stand and examine these Receivers for yourself. Scruti­ nise their every feature . . . for the more searching your investigation the more obvious will K.B. quality Models from 8 GNS. to I6£ GNS. become.

THE K.B. “ALPHADEX” TUNING DIAL . . . the simplest method of tuning at Radiolympia. Stations RADIO arranged alphabetically, enabling you to *111116 t0 your desired programme instantaneously.

tcveans the world to

Gall and see full range of K.B. Receivers at STAND or write for full particulars

CRAY WORKS, SIDCUP, KENTj • > 12 1 INDEX TO EXHIBITORS STANDS

STAND NO. STAND NO. A Eddystone Radio (Stratton & Co., Ltd.)... 23 Ace Radio, Ltd...... 103 Edison Swan Electric Co., Ltd. ... . 57 Aerialite, Ltd. ... 28 “ Efficiency Magazine ”...... 221 Aerodyne Radio, Ltd...... 52 Elf, Ltd., Gordon ...... 95 All-Power Transformers, Ltd. ... 209 Ensign, Ltd. (Houghton’s the Whole­ Amalgamated Press, Ltd...... 13 salers) ...... T19 Ardente (R. H. Dent, Ltd.) 2 Ever Ready Radio, Ltd...... 58 Armstrong Mfg. Co...... 220 Everett Edgcumbe & Co., Ltd...... 164 Assurance Finance Trust, Ltd...... 219 Automatic Coil Winder & Electrical F Equipment Co., Ltd. ... 30, 166 Ferranti, Ltd. 21, 74 Film Industries, Ltd. 4 B .. T7 Baird Television, Ltd. ... 87 Flinders (Wholesale), Ltd. Barratt & Robinson, Ltd. 201 Fuller Accumulator Co. (1926), Ltd. ... 100 Balcombe, Ltd., A. J...... 55 Beethoven Radio, Ltd. 34 G Belling & Lee, Ltd...... 42 Gambrell Electrical Equipment Co., Ltd. 14 Benjamin Electric Ltd. ... 17 Garrard Engg. & Mfg. Co., Ltd...... 37 Bernard Jones Publications, Ltd.... 105 General Electric Co., Ltd. 54, 62 Bifurcated & Tubular Rivet Co., Ltd. 151 Gilbert & Co., Ltd., C. ... T17 Bowmakcr, Ltd...... 217 Goodmans Industries, Ltd...... 43 Bridger & Co., Ltd., R. O. 150 Gramophone Co., Ltd. (His Master’s Britannia Batteries, Ltd. 83 Voice) ...... 66, 76 British Belmont Radio, Ltd. ... 79 British Broadcasting Corporation 51,78 H British Centralab, Ltd...... 153 Halcyon Radio, Ltd...... 35 British G.W.Z. Battery Co., Ltd. ... 82 Harries Thermionics, Ltd. 3 British Mechanical Productions, Ltd. 94 Harris & Russell, Ltd...... T12 British Metal Engraving Co., Ltd. 158 Haynes Radio ...... 11 British Pix Co., Ltd...... 211 Heayberd & Co., Ltd., F. C. ... 25 British Railways ...... 9 Henleys Telegraph Works Co., Ltd.,W. T. 20 British Rola Co., Ltd...... 41 High Vacuum Valve Co., Ltd. ... s ... 27 British Television Supplies, Ltd. 47 Hillman Brothers, Ltd...... 216 British Tungsram Radio Works, Ltd. 36 His Master’s Voice...... 66, 76 British Wireless for the Blind Fund 46 Hobday Brothers, Ltd...... T10 “ Broadcaster,” The T2 Houghton’s the Wholesalers (Ensign, Brown Brothers, Ltd...... T18 Ltd.) ...... T19 Bulgin & Co., Ltd., A. F...... 1 Hunt, Ltd., A. H. ... 155 Bumdept, Ltd...... 85 I Bush Radio, Ltd...... 70 Iliffe & Sons, Ltd. 7 c Invicta Radio, Ltd. ... 56 Cadisch, R., & Sons ...... T9 J Celestion, Ltd...... 26 ... 93 Chloride Electrical Storage Co., Ltd. 32 Jackson Brothers (London), Ltd. Cole, Ltd., E. K...... 69 Collaro, Ltd...... 101 K Cosmocord, Ltd...... 48 Kolster-Brandes, Ltd. ... 65 Cossor, Ltd., A. C...... 61, 163 L Crypton Equipment, Ltd...... 202 L.E.S. Distributors, Ltd. ... T6 D Lissen, Ltd. ... 73 Davies, D. M. (Slough), Ltd. ... 16 Lugton & Co., Ltd. ... T15 Davis & Timmins, Ltd...... 213 Decca Gramophone Co., Ltd. ... 71 M Department of Overseas Trade ... 49 Manufacturers Accessories Co. (1928), De La Rue & Co., Ltd., Thos. ... 6 Ltd...... T4 Dew & Co., Ltd., A. J...... T20 Marconiphone Co., Ltd. ... 53,64 Dibben, Ltd., Horace ...... T8 May & Baker, Ltd. ... 157 Dubilier Condenser Co. (1925), Ltd. ... 81 McMichael Radio, Ltd. ... 59 Dynaport Radio & Television, Ltd. Mercantile Credit Co., Ltd. 215 (Portadyne Radio) ... 18 Mica & Micanite Supplies, Ltd. 154 Dynatron Radio, Ltd. ... 104 Milncs Radio Co., Ltd. ... 88 Dyson & Co., Ltd., J. ... T14 Milliard Radio Valve Co., Ltd. ... 72,161 N E New Era Publishing Co., Ltd. ... 8 East London Rubber Co., Ltd...... T16 New London Electron Works, Ltd. 80 Eastick & Sons, Ltd., J. J. ... T3 Newnes, Ltd., Geo...... 10 Eavestaff & Sons, Ltd., W. G...... 204 Norman Rose (Electrical), Ltd...... 207 Econasign Co., Ltd. ... 222 13 Continued on page 15. A complete RANGE 1937-38 —inclutling the sensational new II The new Alba “ armchair radio ” provides a delightful piece of furniture for the ARMCHAIR Recline at ease and modern home. I / within your reach is a world of entertainment. RADIOS This new Alba serves as an occasional table—the controls sunken so that a tray may be placed on top. Lovely to look at—delightful to own— Alba “Armchair Radio.”

VadioC/HiMS & 'Peedms for eeety Purse V-VuY/wse

14 .B1BL10THEE&

Index to Exhibitors—continued. N.V.H.R#

STAND NO. STAND NO. O Steatite & Porcelain Products, Ltd. ... 152 Olds Discount Co., Ltd...... 218 Sterling Batteries, Ltd...... 5 Stratton & Co., Ltd. (Eddystone Radio) 23 P Partridge Wilson & Co., Ltd. ... 29 T Philips Lamps, Ltd. 68 Tannoy Products ...... 86 Pilot Radio, Ltd...... 84 Telegraph Condenser Co., Ltd. ... 38 Plessey Co., Ltd...... 22 Telsen Electric Co. (1935), Ltd.... 90 Portadyne Radio ... 18 Texaloom Radio, Ltd...... 15 Pye, Ltd...... 60 The 362 Radio Valve Co., Ltd. ... 210 Thompson, Diamond & Butcher ... T5 R Tucker Eyelet Co., Ltd., George ... 102 Radio Gramophone Development Co., Ltd...... 67 Radiometers, Ltd...... 162 u “ Radio Pictorial ” ...... 105 Ultra Electric, Ltd. ... 63 Radio Society of Gt. Britain 214 Rawlplug Co., Ltd. 91 V Regentone Products, Ltd...... 97 Varley (Oliver Pell Control, Ltd.) ... 99 Reslo (Sound Equipment), Ltd. 24 Vidor, Ltd...... 33 Rists Wires & Cables, Ltd. ... 159 Rose (Electrical), Ltd., Norman ...... 207 w Webber & Co., Ltd., J. M. ...Til S Wcstinghouse Brake & Signal Co., Ltd. 77 Salford Electrical Instruments, Ltd. ... 168 Weston Electrical Instrument Co., Ltd. 167 Scott Insulated Wire Co., Ltd...... 156 Whitclcy Electrical Radio Co., Ltd. ... 75 Selecta Gramophones, Ltd. T13 Wingrovc & Rogers, Ltd. 44 Shaftesbury Microphones, Ltd...... 92 Wireless Retailers’ Association 203 Siemens Electric Lamps & Supplies, Ltd. 31 “ Wireless Trader ” ... Tl Sound Sales, Ltd. ... 89 | Wright & Weaire, Ltd...... 165 NOTE.—Stands I to 105 are In the Grand Hall, Ground Floor: Stands 150 to 159 (the Manufacturers'Suppliers Section), Stands 160 to 168 (the Instrument Section), Stands Tl to T20 (the Trade Section) and Stands 201 to 222 (General Exhibits) are In the Grand Hall Gallery.

OFFICES No. No. Burndept, Ltd. ...Oil Lissen, Ltd...... 012 Cole, Ltd., E.K...... 02 Marconiphone Co., Ltd...... 05 Cossor, Ltd., A. C. 07 Mullard Radio Valve Co., Ltd. 03 Edison Swan Electric Co., Ltd. 09 Philips Lamps, Ltd. ...017 Ever Ready Radio, Ltd. ... 020 Pye, Ltd...... 015 Ferranti, Ltd...... 014 Radio Gramophone Development Co., General Electric Co., Ltd. 08 Ltd...... 010 His Master’s Voice 06 Ultra Electric, Ltd...... 04 Invicta Radio, Ltd. ...016 Whitclcy Electrical Radio Co., Ltd. 013 Kolster-Brandes, Ltd. ...018, 019 Wingrove & Rogers, Ltd. ... Ol

NOTE.—All offices are situated In the Grand Hall Annexe, Ground Floor.

TELEVISION DEMONSTRATION ROOMS ROOM NO. ROOM NO. Baird Television, Ltd. 8 His Master’s Voice ... 14 Cole, Ltd., E. K. 3 Kolster-Brandes, Ltd. 11 5 Cossor, Ltd., A. C. 2 Marconiphone Co., Ltd Philips Lamps, Ltd. 4 Edison Swan Electric Co., Ltd. 7 Pye, Ltd...... 6 Ferranti, Ltd...... 9 Radio Gramophone Development Co., General Electric Co., Ltd. 10 Ltd...... 1 Halcyon Radio, Ltd. 13 Ultra Electric, Ltd. ... 12 NOTE.—The Television Demonstration Rooms are In the National Hall.

SPECIAL EXHIBITS. Radiolympia Theatre ...... National Hall, Ground Floor. Television Demonstrations...... National Hall, Ground Floor. Radiolympia Museum ...... Grand Hall, Gallery, Stand 212. G.P.O. Exhibit of Electrical Interference Grand Hall, Ground Floor, Stand 98. 15 %

STAND NUMBER 7

The Wireless

The Practical Radio and Television Journal. Gives the best technical help for all who are interested in wireless. “THE WIRELESS WORLD” covers every wireless interest and gives both technical and general radio news of the week. It contains the very latest information on set construction and television, and includes articles on broadcasting and other topics. SPECIAL FEATURES INCLUDE : Theoretical articles discussing new principles ; Detailed technical reviews of commercial radio receivers; Practical hints on set maintenance and adjustment; Designs for receivers and other apparatus embodying new principles in valves, components and circuit arrangements. EVERY FRIDAY, 4d. Subscription : Home and Canada, £1 Is. 8d. Other Countries, £1 3s. lOd. per annum, post free.

THE THE WIRELESS ENGINEER is published in the interest of pro­ WIRELESS fessional engineers and experi­ menters. Its articles are contri­ buted by experts and specialists ENGINEER in different branches of wireless The Journal of communication. A notable exclusive monthly fea­ Radio Research ture consists of a summary under and Progress the title of Abstracts and Refer-, ences of important articles ap pear­ MONTHLY 2s. 6d. net ing in technical wireless publica­ Subscription £1 12s. per annum tions throughout the world.

ILIFFE & SONS LTD., DORSET HOUSE, STAMFORD ST., LONDON, S.E.1

Make sure of your copies of "THE WIRELESS WORLD" Special Show Numbers. "THE WIRELESS ENGINEER" and books on wireless subjects are obtainable at Stand No. 7.

16 EXHIBITION TELEPHONE INDEX.

R.M.A. Numbers. Shepherd’s Bush. Director’s Office ...... 3403/3407 Exhibitions Organisers’ Office 3955, 3403/3407 Information Bureau ...... 4001 Press Office ...... 3682, 3763 Secretary’s Office...... i ... 4338, 4339

Exhibitors’ Numbers.

Fulham. Fulham. Ardente (R. H. Dent, Ltd.) ...... 9500 ■ Halcyon Radio, Ltd...... 9305 Assurance Finance Trust, Ltd. ... 9307 Heayberd & Co., Ltd., F. C. ... 9407 Automatic Coil Winder & Electrical High Vacuum Valve Co., Ltd. 9410 Equipment Co., Ltd. ... 9608 His Master’s Voice ...... 9101/9 Hobday Brothers, Ltd. 9403 Baird Television, Ltd. ... 9301 Hunt, Ltd., A. H...... 9413 Balcombe, Ltd., A. J...... 9801 Beethoven Radio, Ltd. 9208 Iliffe & Sons, Ltd. ... 9706 Belling & Lee, Ltd. 9609 Invicta Radio, Ltd. ... 9312 Benjamin Electric, Ltd. 9708 Bridger & Co., Ltd., R. O. 9707 L.E.S. Distributors, Ltd...... 9309 British Belmont Radio, Ltd. ... 9502 Lissen, Ltd...... 9404 & 9505 British G.W.Z. Battery Co., Ltd. 9504 British N.S.F. Co., Ltd. 9425 ... 9501 British Rola Co., Ltd...... 9308 McMichael Radio, Ltd. Marconiphone Co., Ltd. ...9001/4 “ Broadcaster,” The ...... 9405 Mica & Micanitc Supplies, Ltd. 9310 Brown Brothers, Ltd. ... 9503 Mullard Wireless Service Co., Ltd. ... 9511 Bulgin & Co., Ltd., A. F. 9209 Bush Radio, Ltd...... 9808 New London Electron Works, Ltd. * . . 9213 Newnes, Ltd., Geo. ... 9607 Cadisch & Sons, R. ... 9604 Celestion, Ltd...... 9507 Chloride Electrical Storage Co., Ltd, 9206 Odhams Press, Ltd. ... 9405 Collaro, Ltd...... 9508 Cosmocord, Ltd. 9306 Philips Lamps, Ltd...... 9632 & 9640 Cossor, Ltd., A. C. 9212 Pilot Radio, Ltd...... 9601 Crypton Equipment, Ltd. ... 9412 Pye, Ltd...... 9809

Davies (Slough), Ltd., D. M. ... 9703. Radio Gramophone Devt. Co., Ltd. ... 9709 Decca Gramophone Co., Ltd...... 9411 Radio Society of Great Britain ... 9512 De La Rue & Co., Ltd., Thos. ... 9800 Rists’ Wires & Cables, Ltd...... 9806 Dubilier Condenser Co. (1925), Ltd. 9803 Dyson & Co., Ltd., J...... 9201 Selecta Gramophones, Ltd...... 9705 Sound Sales, Ltd...... 9606 Eastick & Sons, Ltd., J. J...... 9204 Steatite & Porcelain Products, Ltd. 9211 Eddystone Radio (Stratton & Co., Ltd.) 9605 Sterling Batteries, Ltd. ... 9602n Edison Swan Electric Co., Ltd. 9406 & 9426 Stratton & Co., Ltd. (Eddystone Radio) 9605 Elf, Ltd. (Gordon) ' ...... 9702 Ensign, Ltd. (Houghtons the Whole­ Telegraph Condenser Co., Ltd. ... 9408 salers) ...... 9311 Trader Publishing Co., Ltd. ... 9631 & 9641 Ever Ready Radio, Ltd. ... 9205 & 9240 Tucker Eyelet Co., Ltd., George ... 9409 Film Industries, Ltd...... 9302 Ultra Electric, Ltd. ... 9313 Fuller Accumulator Co. (1926), Ltd, 9509 Westinghouse Brake & Signal Co., Ltd. 9303 Garrard Engg. & Mfg. Co., Ltd. ... 9207 Whiteley Electrical Radio, Ltd. ... 9805 General Electric Co., Ltd. 9005/6/7 Wingrove & Rogers, Ltd. ... 9401 Gilbert'& Co., Ltd., C. ... 9304 “ Wireless & Electrical Trader ” 9631,9641 Gramophone Co., Ltd. ...9101/9 Wireless Retailers’ Association ... 9203

17 li ; >

BROADCASTING STATIONS Their Characteristics and Times of Transmission.

BRITISH STATIONS.

Power Frequen- Wave- Approximate Times of (in kw.) cy (in lentgh Transmission. Station. j (Copen­ kilo- (in hagen cycles per metres), Rating). second). Weekdays. Sundays.

Droitwich National 150 200 1500 10.15 a.m. to 12 mid­ 9.30 a.m. to night. 10.45 a.m. I 12.30 p.m. to 10.45 p.m. Midland Regional 70 1013 296.2 10.15 a.m. to 12 mid- 4.0 p.m. to night. 10.45 p.m. London National 1 20 1149 261.1 5.0 p.m. to 12 mid­ 4.0 p.m. to night. 10.45 p.m. London Regional 70 ! 877 342.1 40.15 a.m. to 12 mid­ 12.30 p.m. to night. 10.45 p.m.

North National 20 1149 I 261.1 5.0 p.m. to 12 mid­ 4.0 p.m. to 1 night. 10.45 p.m.

North Regional 70 668 449.1 10.15 a.m. to 12 mid­ 12.30 p.m. to i night. 10.45 p.m. Scottish National 50 1149 261.1 40.45 a.m. to 12 mid-! 4.0 p.m. to night. 10.45 p.m.

Scottish Regional 70 10.15 a.m. to 12 mid- 12.30 p.m. to Burghead ... 60 767 391.1 } night. 10.45 p.m. Welsh Regional 12.30 p.m. to Penmon 804 373.1 40.15 a.m. to 12 mid- ' night. 10.45 p.m. West of England . Regional 50 1050 285.7 !5.0 p.m. to 10.0 p.m. 4.0 p.m. to 10.45 p.m.

Northern Ireland 100 977 307.1 40.15 a.m. to 12 mid­ 12.30 p.m. to night. 10.45 p.m.

Aberdeen ... 1 1285 233.5 40.15 a.m. to 12 mid- 12.30 p.m. to j night. 10.45 p.m. i i Bournemouth 1 1474 203.5 40.15 a.m. to 12mid- 12.30 p.m. to j night. 10.45 p.m. . *Newcastle ... 1 1122 267.4 10.15 a.m. to ^mid­ 12.30 p.m. to night. 10.45 p.m. ; ! Plymouth ... i 0.31474 203.5 40.15 a.m. to ^mid­ 12.30 p.m. to night. 10.45 p;m. i i ; August, 1937. : Note :—This list has been compiled with the assistance of the British Broadcasting Corporation. The times of transmission given above are intended as a general guide only and must not be taken to imply that the stations give continuous programmes between the hours stated. Additional items may be broadcast outside these hours. * To be replaced by a 6okW transmitter on the same wavelength at Stagshaw, 15 miles west of -• : Newcastle, in October, 1937. I 18 ; BROADCASTING STATIONS—continued.

EUROPEAN STATIONS.

(In decreasing order of Wave-length.)

This list has been prepared from the latest available databy the Radio International Programmes Services, Limited, the sole contractors for foreign broadcasting programmes to the London daily papers and the provincial and wireless press. No. of Wave­ Power Station and Kilo­ length in Hours of Transmission. Country. cycles in Kilo­ per sec. Metres. watts. Weekdays. Sundays. Kaunas, Lithuania 155 1,961 7 12 noon to 9 p.m. 9.15 a.m. to 10 p.m. Radio Roumania, 160 1,875 150 7 or 8.30 p.m. to 10.55 7.40 to 11 p.m. (appr.). Roumania p.m. on Mondays and Tuesdays. Hilvcrsum No. 1, 160 1,875 10 -150 7.40 a.m. to 11.40 p.m. 8.10 a.m. to 11.10 p.m. Holland Lahti, Finland 165.9 1,807.2; 150 7.5 a.m. to 11 p.m. 8 a.m. to 11 p.m. Moscow (RW1), 172 1,744 500 5.30 p.m. to 1 a.m. 5.30 p.m. to 1 a.m. U.S.S.R. Saturdays : 12.30 p.m. to 1 a.m. Paris (Radio Paris), 182 1,648 80 1 6.50 a.m. to between 11 6.50 a.m. to 1 a.m. France ■ p.m. and 1 a.m. Berlin (Deutsch- 191 1,571 60 6 a.m. to 12 midnight. 6 a.m. to 12.55 a.m. landsender), Saturdays : Till 12.55 Germany I a.m. Minsk, U.S.S.R. ... 208 1,442 35 10.5 p.m. to 12 midnight. 10.5 p.m. to 12 midnight. Reykjavik, Iceland 208 1,442 16 12 noon to 12 midnight 11.45 a.m. to 2 a.m. (appr.). Closes at 2 a.m. on Saturdays. Motala, Sweden ... 215.9 1,388.9 150 See Stockholm (426.1 m.). Warsaw, Poland ... 224 ! 1,339 120 6.15 a.m. to 11.15 p.m. 8 a.m. to 11 p.m. Leningrad (RZS), 232 | 1,293 100 5 p.m. to 2 a.m. 5 p.m. to 2 a.m. U.S.S.R. Luxembourg, 232 1,293 200 6.55 a.m. to 11.30 p.m. 7.5 a.m. to 12 midnight. Luxembourg Till 1 a.m. on Saturdays. Kalundborg, 240 1,250 60 7 a.m. to 12.30 a.m. 8 a.m. to 12.30 a.m. Denmark Kiev I, U.S.S.R. ... 247.8 1,210 100 9 p.m. to 12 midnight 9 p.m. to 12 midnight. or 10.5 p.m. to 12 midnight. Vigra, Norway 253 1,186 10 See Oslo (1153.8 m.). Tashkent (RV11) 256.4 1,170 25 U.S.S.R. Oslo, Norway 260 1,153.8 60 11.10 a.m. to 11 p.m. 9 a.m. to 11.15 p.m.! (appr.). Tromso, Norway... 282 1,065 10 See Oslo (1153.8 m). Tiflis (RV7) 283 1,060 35 U.S.S.R. Finnmark, Norway 347 864 10 See Oslo (1153.8 m.). Budapest No. 2, 359.5 834.5 18 About 7 to 9 p.m. Varies 11.30 a.m. to 9.30 p.m. Hungary greatly. Sverdlovsk,U.S.S.R. 375 800 40 Banska-Bystrica, 392 765 30 Relays other Czech sta­ Czechoslovakia tions between 6.30 a.m. and 11.30 p.m. (Sundays), 6 to 11.30 p.m. (Saturdays) and 6 to 11 p.m. (week­ days). Boden, Sweden ... 391.9 765.3 0.6 See Stockholm (426.1 m). Geneva, 401 748 1.3 See Sottens (443.1 m.). Switzerland Moscow (VZSPS), 413.5 726 100 5 or 5.30 to 11 p.m. 5.30 to 11 p.m. U.S.S.R. Ostersund, Sweden 413.2 725.5 0.6 1 See Stockholm (426.1 m.). Tartu, Esthonia ... 518 579.2 0.5 ! See Tallinn (410.4 m.). Hamar, Norway ... 519 578 0.7 i See Oslo (1153.8 m.). 19 {Continued on next page.) B2 sr

BROADCASTING STATIONS—continued.

EUROPEAN STATIONS. (In decreasing order of Wave-length.) No. of Wave- Power I Station and Kilo­ length in . Hours of Transmission. Country. cycles in Kilo- Metres. watts. : Sundays. per sec. I Weekdays. Innsbruck, Austria 519 578 1 See Vienna (506.8 m). Own transmissions on weekdays at noon, 3 and 7 p.m. Fridays, and Saturdays at 10.45 and 11.20 a.m. Ljubljana, 527 569.3 6.3 12 noon to 10.30 p.m. 8 a.m. to 10.30 p.m. Yugoslavia (appr.). Viipuri, Finland ... 527 569.3 10 See Lahti (1807.2 m.). Bolzano, Italy 536 559.7 10 See Milan No. 1 (368.6 m.). Wilno, Poland 536 559.7 50 6.15 a.m. to 11.10 p.m. : 8 a.m. to 11.30 p.m. Till 11.30 Saturdays. ; Budapest No. 1, 544.6 550.5 120 6.45 a.m. to 12.15 a.m. : 9.30 a.m. to 12.15 a.m. Hungary (appr.). (appr.). Beromunster, 556 539.6 100 6.15 a.m. Closing time j 10 a.m. to 11 p.m. Switzerland very variable. Athlone, Irish F.S. 565 531 100 1.30 to 11 p.m. 1.30 to 11.30 p.m. Klaipeda, Lithuania 565 531 10 2.15 to 8.55 p.m. 9.30 a.m. to 10.30 p.m. Palermo, Italy 565 531 3 See Rome (420.8 m.). Stuttgart, Germany 574 522.6 100 5 a.m. to 2 a.m. ■ 6 a.m. to 1 a.m. Alpes Grenoble, 583 514.6 15 6.30 a.m. to 11.15 p.m. 6.50 a.m. to 11.15 p.m. France Madona, Latvia ... 583 514.6 50 See Riga (238.5 m.). Vienna (Bisamberg) 592 506.8 100-120 6.45 a.m. to 11.30 p.m. 7.45 a.m. to 11.30 p.m. Austria Sundsvall, Sweden 601 499.2 10 See Stockholm (426.1 m.). Rabat, Morocco ... 601 499.2 25 Florence, Italy 610 491.8 20 See Milan (368.6 m.). Brussels No. 1, 619.5 483.9 15 6.37 a.m. to 11 p.m. I 6.37 a.m. to 12 midnight. Belgium Saturdays till 12 mid- Pigeon racing 5 a.m. on night. Saturdays and Sun­ days. Lisbon, Portugal ... 629 476.9 15 Kristi ansand, 629 476.9 20 See Oslo (1153.8 m.). Trondelag, Norway PragueNo. 1 (Liblice) 638 470.2 120 6 a.m. to 11 p.m. 6.30 a.m. to 11.30 p.m. Czechoslovakia Lyons-la-Doua, 648 463 100 6.30 a.m. to 11 p.m. or 6.50 a.m. to 12 midnight. France 12 midnight. Cologne, Germany 658 455.9 100 5.50 a.m. to 12 midnight. 6 a.m. to 12 midnight. Sottens, 677 443.1 100 12.29 to 10.30 p.m. or | 9.55 a.m. (appr.) to Switzerland 11.30 p.m. 10.30 p.m. (appr.). Belgrade, 686 437.3 2.5 12 noon to 11 or 11.30 9.30 a.m. to 11.30 p.m. Yugoslavia (appr.), on Saturdays till 11.30 p.m. ! Paris (PTT), 695 431.7 120 6.30 a.m. to 11.15 p.m. 6.30 a.m. to between 12 France (appr.). Closes be­ midnight and 1 a.m. tween midnight and 1 a.m. on Saturdays. Stockholm, Sweden 704 426.1 55 7.45 a.m. to 11 p.m. 9.30 a.m. to 11 p.m. ’ Rome, Italy 713420.8 50 7.30 a.m. to 11.30 p.m. 8.30 a.m. to 12 midnight. t Bergen, Norway 722 415.5 1 See Oslo (1153.8 m.). i Frederikstad •: Seville, Spain 731 410.4 1.5 i Tallinn, Esthonia... 731 410.4 20 6 a.m. to 10 p.m. 7.30 a.m. to 10 p.m. Munich, Germany 704 405.4 100 6 a.m. to 12 midnight. 6 a.m. to 12 midnight. 1 Marseilles-Provence 749 400.5 100 6.30 a.m. to 11.15 p.m. 6.50 a.m. to 11.15 p.m. France Katowice, Poland... 751.8 398.8 10 6.30 to 11 p.m. 6 a.m. to 11.30 p.m. T oulouse-Pyr6n6ss, 776 386.6 120 6.30 a.m. to 12 midnight. 6.50 a.m. to 12 midnight, France (appr.). Leipzig, Germany 785 382.2 120 5.50 a.m. to 12 midnight. 6 a.m. to 12 midnight. Lwow, Poland 796 377.4 50 6.15 a.m. to 2 a.m. 8 a.m. to to 2 a.m. 20 (Continued on next, page.) t. BROADCASTING STATIONS—continued.

EUROPEAN STATIONS. (hi decreasing order of Wave-length.) No. of Wave- | Power Station and Kilo­ length 1 in Hours of Transmission. Country. cycles in Kilo- per sec. Metres. watts. Weekdays. Sundays. Barcelona, Spain ... 795 377.4 7.5 8 a.m. to 12 midnight. 8 a.m. to 12 midnight. Milan No. 1, Italy 814 368.6 50 7.45 a.m. to 11.55 p.m. 8.30 a.m. to 12 midnight. Till 12.30 a.m. on Saturdays. Bucharest, Romania 823 364.5 12 5.30 a.m. to 11 p.m. 6.30 a.m. to 11 p.m. Agen, France 832 360.6 1.5 12 noon to 10.15 p.m. 12 noon to 10.15 p.m. Berlin(Funkstunde), 841 j 356.7 100 6 a.m. to 12 midnight. 6 a.m. to 12.55 a.m. Germany Saturdays till 1 a.m. Bodo | 10 Porsgrund - Norway 850 352.9 1 See Oslo (1153.8 m.). Stavanger J 10 Sofia, Bulgaria 850 352.9 0.75 5.45 a.m. to 11 p.m. 5.45 a.m. to 11 p.m. Valencia, Spain ... 850 352.9 3 Strasbourg (PTT), 859 j 349.2 100 6.45 a.m. to 11.30 p.m. 6.50 a.m. to 12 midnight, France (appr.). Poznan, Poland ... 868 345.6: 16 6.15 a.m. to 11.30 p.m. j 8 a.m. to 11.30 p.m. Graz, Austria 886 338.61 15 See Vienna (506.8 m.). Linz, Relays own transmis­ sions on weekdays at noon and between 2 and 3 p.m. Helsinki, Finland... 895 335.2 10 See Lahti (1807.2 m.). Limoges, France ... 895 335.2 500 6.30 a.m. to 11.15 p.m. 6.50 a.m. to 11.15 p.m. Hamburg, Germany 904 331.9 100 5.45 a.m. to 12 midnight. 6 a.m. to 12 midnight. Saturdays till 1 a.m. I Toulouse (Radio- 913 328.6 60 8.30 a.m. to 12 midnight. .11.45 a.m. to 12 mid­ Toulouse), France night. Brno,Czechoslovakia 922 325.4 32 6 a.m. to 11 or 11.30 p.m. 6.30 a.m. to 11.30 p.m. Brussels No. 2, 931.4 321.9 15 6.37 a.m. to 11 p.m. 6.37 a.m. to 12 midnight. . Belgium Saturdays till 12 mid­ Pigeon racing notes from night. 5 a.m. Saturdays and Sundays. Algiers, N. Africa... 941 318.8 12 7 a.m. to 11 p.m. (appr.). 7 a.m. to 10.30 p.m. Goteborg, Sweden 941 318.8 10 See Stockholm(426.1 m.). Breslau, Germany 950 315.8 100 5 a.m. to 12 midnight. 5 a.m. to 12 midnight. Paris (Poste 959 312.8 60 7.10 a.m. to 11 p.m. 7.52 a.m. to 11.30 p.m. Parisien), France Bordeaux-Sud- 968 309.9 30 8.15 a.m. to 12.15 a.m. 8 a.m. to 12.15 a.m. Ouest, France (Mondays). Odessa, U.S.S.R.... 968 309.9 10 Genoa, Italy 986 304.3 10 See Milan (368.6 m.). Hilvcrsum No. 2, 996 301 15-60 7.40 a.m. to 11.40 p.m. 8.35 a.m. to 11.40 p.m. Holland Bratislava, 1,004 298.8 13.5 6 a.m. to 11 p.m. 6.30 a.m. to 11.30 p.m. Czechoslovakia Saturdays till 11.30 p.m. Cracow, Poland ... 1,022 293.5 1.7 6.15 a.m. to 11.30 p.m. 8 a.m. to 11.30 p.m. Konigsberg (Heils- 1,031 291 100 5.40 a.m. to 12 midnight. 6 a.m. to 12 midnight. berg), Germany Rennes, France ... 1,040 288.6 120 6.50 a.m. to 11.15 p.m. 6.50 a.m. to 11.15 p.m. On Fridays closing time is later and varies. Bari No. 1, Italy ... 1,059 283.3 20 See Rome (420.8 m.). Paris (Radio Cite), 1,068 280.9 0.8 7 a.m. to 11.30 p.m. 8.30 a.m. to 12 midnight. France Bordeaux-Lafayette, 1,077 278.6 13 6.30 a.m. to 11.5 p.m. 6.50 a.m. to 11.5 p.m. France Zagreb, Yugoslavia 1,086 276.2 0.7 12 noon to 11.15 p.m. 11 a.m. to 11.15 p.m. Madrid(EAj7), Spain 1,095 274 5 Kuldiga, Latvia ... 1,104 271.7 25 See Riga (238.5 m.). Naples, Italy 1,104 271.7 1.5 See Rome (420.8 m.). Moravska-Ostrava, 1,113 269.5 11.2 6 a.m. to 11 p.m. (appr.) 6.30 a.m. to 11.30 p.m. Czechoslovakia Saturdays 11.30 p.m. Radio Normandy, 1,113 269.5 10 6.45 a.m. to 1 a.m. 6.45 a.m. to 1 a.m. France Saturdays till 2 a.m. 21 (Continued on next page.) BROADCAST! NG STATIONS—continued.

EUROPEAN STATIONS. [In decreasing order of Wave-length.)

! No. of . Wave­ Power i Station and i Kilo- length in Hours of Transmission. Country. i cycles in Kilo­ : per sec. Metres. watts. ; Weekdays. Sundays. Nyireghyhaza, 1,122 267.4 6.2 See Budapest Hungary (549.5 m.). Horby, Sweden ... 1,131 265.3 10 See Stockholm (426.1 m.). Turin No. 1 Italy 1,140 263.2 7 See Milan (368.6 m.). Trieste 10 Kosice, 1,158 259.1 10 6 a.m. to 11 or 11.30 6.30 a.m. to 11.30 p.m. Czechoslovakia p.m. Monte Ceneri, 1,167 257.1 15 12 noon to 10 p.m. i 11.30 a.m. to 10 p.m. Switzerland (appr.). Copenhagen, 1,176 255 10 See Kalundborg Denmark (1,250 m.). Frankfurt ' Cassel IGcr- : Freiburg 1,195 251 25 6 a.m. to 2 a.m. ; 6 a.m. to 2 a.m. Koblenz many Trier Prague No. 2 1,204 249.2 5 3 to 4 p.m. i 2.30 to 4 p.m. (Strasnice), Czechoslovakia Lille (Radio PTT 1,213 247.3 60 6.30 a.m. to 11.15 p.m. 6.45 a.m. to 11.15 p.m. Nord), France Narvik, Norway ... 1,222 245.1 0.3 See Oslo (1153.8 m.). Gleiwitz ^ Germany Gorlitz 1,231 243.7 5 See Breslau (315.8 m.). Cork, 1,235 242.9 1 See Athlone (531 m.). Irish Free State Riga, Latvia 1,258 238.5 15 5.40 a.m. to 10 p.m. 8 a.m. to 11 p.m. Rome No. 3, Italy 1,258 238.5 1 See Milan (368.6 m.). Numberg, Germany 1,267 236.8 2 See Munich (405.4 m.). Radio M6diterran6e, 1,276 235.1 27 12.15 to 11 p.m. (appr.). 12.15 to 11 p.m. France Varna, Bulgaria ... 1,276 235.1 2 See Sofia (352.9 m.). Dresden, Germany 1,285 233.5 0.25 See Leipzig (382.2 m.). Klagenfurt \Aus- Vorarlberg / tria 1,294 231.8 5 See Vienna (506.8 m.). r Danzig, 1,303 230.2 0.5 Danzig.» Free State Malmo, Sweden ... 1,312 228.7 2.5 See Stockholm (426.1 m.). Bremen 2 Flensburg ^Ger- 2 Hanover ” many 1,330 225.6 2 See Hamburg (331.9m.). Magdeburg 0.5 Stettin 2 Montpellier-Lan- 1,339 224 1.5 6.30 a.m. to 11.15 p.m. 6.50 a.m. to 11.15 p.m. guedoc, -France Relays Paris (PTT). Dublin, 1,348 222.6 0.5 See Athlone (531 m.). Irish Free State s- Konigsberg No. 2, 1,348 222.6 1.5 See Konigsberg Germany (291 m.). Rjukan, Norway ... 1,348 222.6 0.15 See Oslo (1,153.8 m.). Salzburg, Austria 1,348 222.6 2 See Vienna (506.8 m.). Bari No. 2 \Italv 1 TurinNo.2/ltaly 1,357 221.1 0.2 See Rome (420.8 m.). Milan No. 2, Italy 1,357 221.1 4 See Rome (420.8 m.). Notodden, Norway 1,357 221.1 0.3 See Oslo (1,153.8 m.). Basle Switzerland See Beromiinster Berne} 1,375 218.2 0.5 (539.6 m.). Stara Zagora, 1,402 214 2 See Sofia (352.9 m.). Bulgaria Magyarovar \ Hun- 11,438 208.6 1.25 See Budapest (549.5 m.). Miskolcz / gary Paris (Eiffel Tower), 11,456 206 7 7.30 a.m. to 10 p.m. 7.30 a.m. to 10 p.m. France ! (appr.). 22 . < B ROADCASTING STATIONS—continued. SHORT WAVE STATIONS. (In decreasing order of Wave-length.) This list has been prepared from thelatest available data by thcRadio International Programmes Services, Ltd., the sole contractors for foreign broadcasting programmes to the London daily papers and the provincial and wireless press. Frequency Wave­ in length Kilocycles Station. Country. per in Remarks. second. metres.

Batavia (YDA) Java 3,040 98.68 11.30 a.m.-4.30 p.m. Khabarovsk U.S.S.R. 4,273 70.2 8 a.m. -3.0 p.m. Caracas Venezuela 5,800 51.72 Suns., 2.30 p.m. - 4.30 a.m. Weekdays, 1.0 p.m.-3.30 a.m. Tegucigalpa (HRN) ... Honduras 5,866 51.11 7.30 p.m. and 12.30 a.m.-4.0 a.m. Vatican City (HJV) ... Italy ... 5,969 50.26 11 a.m. Sundays. Weekdays, 8 p.m. Daily Transmissions in the following languages : Mons.: Italian. Tues.: English. Weds.: I Spanish. Thurs.: French. Fris.: German. Sats.: Dutch. Havana ... : Cuba...... 6,010 49.96 2 p.m.-5 a.m. Podebrady ... I Czechoslovakia 6,010 49.92 Berlin (Zeesen) (DJC) ! Germany 6,020 | 49.83 For Africa : 5.35 p.m.-10.30 p.m. Pernambuco ...... 1 Brazil ... 6,020 ! 49.83 Transmissions irregular, in so far as days of the week are con­ cerned. Hours : 9.0 p.m.- 2 a.m. Panama ... ' Central America 6,030 49.75 6 p.m. and 11 p.m.-4 a.m. Boston (Mass.) ... i U.S.A. 6,040 49.67 Mons., 12 midnight-2 a.m. Cincinnati ... U.S.A.... 6,060 49.5 5 a.m.-7 a.m. and 11 a.m.-12 I midnight. Skamlebaek (OXY) ... Denmark 6,060 49.5 Relays Kalundborg. Philadelphia (W3XAU) U.S.A. 6,060 49.5 ; 1 a.m.-4 a.m. Georgetown ...... British Guiana 6,070 49.42 Suns., 1.45 p.m.-4.45 p.m. and 10.45 p.m.-3 a.m. Weekdays, 10.45 p.m.-3 a.m. Nairobi Kenya ... 6,080 49.31 i Suns., 5.15 p.m.-8.15 p.m. Mon. to Fri., 12 noon-12.30 p.m., 5.45 p.m.-8.45 p.m. Tues. and Thurs., 2.45 p.m.-3.45 p.m. i Sat., 12 noon-12.45 p.m. and 5.15 p.m.-8.15 p.m. Johannesburg ... South Africa ... 6,097 49.2 . 7.15 a.m.-2 p.m. and 6 p.m.-9.30 p.m. Bound Brook ... U.S.A. 6,100 49.18 Weekdays, 1 a.m.-4 a.m. Suns., 1 a.m.-6 a.m. Mons., 1.30 a.m.- 3.30 a.m. Chicago, IU. (W9XF) U.S.A. 6,100 49.18 4 a.m.-7 a.m. Medellin Colombia 6,100 49.18 5 p.m.-5.30 a.m. Jeloy ... Norway 6,130 48.94 Relays Oslo. Pittsburgh U.S.A. 6,140 48.86 3.0 a.m.-6 a.m. (approx.). Winnipeg Canada 6,150 48.85 12 midnight-6 a.m. Parede (CT1GO) Portugal 6,198 48.4 Santiago Cuba ... 6,200 48.39 2.30 p.m.-5 a.m., except Sats. Lima ... Peru ... 6,246 47.92 1 a.m.-4.30 a.m. Trujillo City ... Dominican 6,310 47.5 On certain weekdays, 5.30 p.m.- Republic. and 4 a.m. 6,340 47.32 10.45 p.m.-12 midnight. Valencia Venezuela 6,516 46.01 5.30 a.m.-4 a.m. Riobamba Ecuador 6,620 45.31 Thurs., 3 a.m.-5.30 a.m. Guayaquil Ecuador 6,640 45.18 Suns., 11.45 p.m.-2 a.m. Santa Cruz Canary Islands 7,010 42.78 Mon., Wed., Fri., Sat., 9.45 p.m.- 10.45 p.m. Lobito Angola...... 7,177 41.78 Wed. and Sats., 8.45-10.45 p.m. Radio Nations Switzerland .. 7,797 38.48 Sats., 11.30 p.m.-12 midnight. Quito ...... Ecuador 8,950 33.5 1.30 a.m.-4 a.m., except Mons. Budapest Hungary 9,125 32.88 Suns., 1 a.m.-2 a.m. Weds., (Szekesfchervar) 1 a.m.-2 a.m. Sats., 12 mid­ night-1 a.m. Melbourne (VK3ME) Australia 9,500 31.58 10 a.m.-l p.m., except Sats.

23 (Continued on next page.) I

BROADCASTING STATIONS—continued. SHORT WAVE STATIONS. (In decreasing order of Wave-length.) Frequency Wave­ m length Kilocycles Station. Country. per in Remarks. second. .metres. Schenectady (W2XAF) U.S.A. ... ; 9,530 31.48 10 p.m.-b a.m. on bats., o p.m.- 6 a.m. Rio de Janeiro Brazil ... 9,500 31.56 10.45 p.m.-l 1.45 p.m. Suva (VPD2) ... Fiji Islands ... 9,540 31.46 Berlin (Zeesen) (DJN) Germany ... 9,540 | 31.45 For East Asia : 6.5 a.m.-11.15 a.m. and 11.55 a.m.-5 p.m. For South America : 10.50 p.m.-4.45 a.m. Podebrady ... i Czechoslovakia 9,550 i 31.41 Berlin (Zeesen) (DJA) Germany 9,560 31.38 For South Asia : 6.5 a.m.-11.15 a.m. For Central America : 10.50 p.m.-4.45 a.m. Bombay (VUB) ... : India ... 9,565 31.36 Lyndhurst (VK3LR) ... Australia 9,580 31.34 Transmission I: for Australia and the Far East, 8 a.m.-12.30 p.m. Transmission III: for Australia, New Caledonia and Noumea, 9 a.m.-9.15 a.m. on Tues. and Thurs. European •* Transmissions : 7.30 a.m.-8.30 a.m. Huizen (PCJ) ... Holland 9,590 : 31.28 Suns., 8 p.m.-9 p.m., Mons., 1 p.m.-2 p.m., Tues., 7.30 p.m.- , 9 p.m., Thurs., 1 p.m.-4 p.m. Philadelphia (W3XAU) , U.S.A. 9,590 , 31.28 5 p.m.-l a.m. Sydney (VK2ME) ... ! Australia 9,590 31.28 Suns., 6 a.m.-7.30 p.m. Radio Nations (HBW) j Switzerland ... 9,595 i 31.27 Sats., 11.30 p.m.-12 midnight. Caracas ... Venezuela 9,600 31.25 Suns., 2.30 p.m.-4.30 p.m. Week­ days, 1 p.m.-3.30 p.m. Moscow (RW96) ... U.S.S.R. 9,600 31.25 12 midnight-2 a.m. Sourabaya (YDB) ... ; Java ... 9,610 31.2 10.30 a.m.-3.30 p.m. Rome (2RO) ...... Italy ... 9,637 31.13 Suns., 12 midnight-12.15 a.m. ' Weekdays, 11.30 p.m. or 12 midnight-1 a.m. (Approx.). Buenos Aires ...... j Argentine 9,669 31.06 llp.m.-6a.m. Lisbon (ClAA) ... • Portugal 9,650 31.06 Tues., Thurs. and Sats., 9.30 ! p.m.-12 midnight. Madrid (EAQ) ... ; Spain ...... ! 9,860 30.43 6.0 p.m.-2.0 a.m. Bandoeng (PMN) ... Java' ...... | 10,260 29.25 11.30a.m.-5p.m.and 12midnight- ! 12.30 a.m. Ruysselede (ORK) ... Belgium ... : 10,330 29.04 7.30-9 p.m. Buenos Aires ...... | Argentine ... 10,350 28.98 11 p.m.-12 midnight on certain days of the week. Bandoeng (PLP) ... ■ Java ... 11,000 27.25 11 a.m.-5 p.m. and 12 midnight- 12.30 a.m. Lisbon (CTV2) Portugal ... 11,040 27.17 9 p.m.-l a.m. Station Radio Coloniale de l’Etat francais ... France 11,720 25.6 11.15 p.m.-6 a.m. Winnipeg (VE9JR) ... Canada 11,720 25.6 12 midnight-6 a.m. Saigon Indo China 11,730 25.58 11.30 a.m.-3.30 p.m. Berlin (Zeesen) (DJD) Germany 11,770 25.49 For N. America : 10.50 p.m.- 4.45 a.m. For Africa : 5.35 p.m.-10.30 p.m. Boston (Mass.) ... U.S.A. 11,790 25.45 Except Suns., 10 p.m.-10.30 p.m. Tokio (JZJ) ...... | Japan ... 11,800 25.42 2 p.m.-3 p.m. and 9 p.m.-l 1.30 p.m. Vienna (Experimental) Austria 11,800 25.42 4 p.m,-11 p.m. Rome (2RO) ...... | Italy ... 11,810 25.4 2.20 p.m. - 7.30 p.m. Wayne (W2XE) ... ; U.S.A. 11,830 25.36 Times variable. Usually from 11.30 p.m. to about 2 a.m. Podebrady Czechoslovakia 11,840 25.34 8.30 p.m. to 10.30 p.m., often longer and sometimes till 2 or 3 a.m. Pittsburgh ...... U.S.A. 11,870 25.27 12 midnight-3 a.m. Station Radio Coloniale de PE tat francais ... 1 France 11,880 25.24 7.15 a.m.-10 a.m. and 5.15 p.m.- 11 p.m. 24 ('Continued on next page.) BROADCASTING STATIONS—continued. SHORT WAVE STATIONS. {In decreasing order of Wave-length.) Frequency Wave­ in length Kilocycles Station. Country. per in Remarks. second. metres. Moscow (VZSPS) ... j U.S.S.R. 12,000 25 Suns.: 4.15 p.m.-5 p.m. Broad­ casts on weekdays at irregular intervals in the evenings, also relaying Moscow (RW1). Lisbon (CTICT) ... : Portugal 12,080 24.83 Suns., 8.40 p.m. - 9.30 p.m. Reykjavik Iceland 12,235 24.52 Suns., 8.40 p.m. - 9.30 p.m. Parcde (CITGO) Portugal 12,400 24.2 Warsaw . , Poland 13,635 22.10 Mons., Weds., Fris., 6.30 p.m. - 7.30 p.m. Suns., 5.30 p.m. - : 7.30 p.m. Sofia ... Bulgaria 14,970 20.04 Suns., relays Longwave station. Mons., Tues. and Fris., 11 a.m.- 12.30 p.m. and 6 p.m.-8.45 p.m. Weds., 11 a.m.-12.30 p.m. and I 6 p.m.-ll p.m. Thurs., 11 a.m. - 12.30 p.m. and 6.0 p.m. - I 10.10 p.m. Sats., 11 a.m.-12.30

’ p.m. and 4.30 p.m. - 11 p.m. Moscow (RW96) ... U.S.S.R. ... 15,038 19.95 Suns., 7 p.m. - 9 p.m. Berlin (Zecsen) (DJL) Germany ... 15,110 19.85 For North America : 2-3 p.m. For Africa : 6 a.m.-8 a.m. and 5.35 p.m. - 10.30 p.m. Suns, I only, 12 noon - 2 p.m. Vatican City ...... Italy ...... 15,123 19.84 4.30 p.m. weekdays. Daily trans­ missions in the following lan­ guages : Mon.: Italian. Tues.: English. Wed.: Spanish. Th.: French. Fri.: German. Sat.: Dutch. Tokio ... Japan ...... 15,160 19.79 6.30 a.m. - 7.30 a.m., 2 p.m. - 3 p.m. and 9 p.m. - 11.30 p.m. Berlin (Zecsen) (DJB) Germany ... 15,200 19.74 For North America : 10.50 p.m.- 4.45 a.m. and 5.10 p.m. - 6.25 p.m. Also on Suns., 2. p.m. - 3 p.m. For South Asia : 6 a.m. 11.15 a.m. and 11.55 : a.m. - 5 p.m. Pittsburgh ... U.S.A. ... 15,210 19.71 2 p.m. - 12 midnight. Huizen (PCJ) ... Holland ... : 15,220 19.71 Tues., 10.30 a.m.-12 noon, Wed., I 2 p.m. - 5 p.m. Podebrady ... j Czechoslovakia J 15,230 19.70 8 p.m. - 8.15 p.m. Station Radio Coloniale de l’Etat francais ... France ... 15,234 19.68 11.0 a.m. - 4 p.m. Wayne (W2XE) U.S.A. ... 15,270 19.64 Times very variable. About 7 or 8 p.m. Berlin (Zeesen) (DJQ) Germany ... 15,280 19.63 For East Asia : 6.5 a.m. - 11.15 p.m. and 2.15 p.m. - 5 p.m. For South America : 12 noon - 2 p.m. and 10.50 p.m. - 4.45 1 a.m. Buenos Aires (LRV) ... Argentine . ... 15,280 19.63 1 p.m. - 12 midnight. Berlin (Zecsen) (DJR) Germany ... 15,330 19.56 For Central America : 2 p.m. - 3 p.m. and 10.50 - 4.45 a.m. Schenectady (W2XAD) U.S.A. ... 15,330 19.56 4 p.m. - 2 a.m. Budapest (Szekesfchcr- Hungary 15,370 19.52 Suns., from 3 p.m. - 4 p.m. var) (HAS3) Berlin Germany ... 17,760 16.89 For East Asia : 6.5 a.m. - 11.15 (Zecsen) (DJE) a.m. and 11.55 a.m. - 5 p.m. On Sundays,for South America: 5.10 p.m. - 6.25 p.m. Huizen (PHI) ... Holland ... 17,770 16.88 Suns., 1 p.m. - 4 p.m.; Mon., Tues., Thurs., Fri., 2 p,m. - 3.30 p.m.; Sat. 2 p.m. - 4 p.m. Bound Brook (W3XAL) U.S.A. ... 17,780 16.87 Suns., from 1 p.m. - 12 midnight. Weekdays, 12.30 p.m. - 12.15 a.m. Pittsburgh U.S.A. ... 21,540 ' 13.92 10.45 a.m. - 1 p.m.______25 30Z&I66 GALLERY Big savings in time and costs can be effected by the use of DOUGLAS Automatic Coil Winders. There are DOUGLAS Machines to meet every need. The Model F.A.P.I., illustrated, winds up to 12 coils simultaneously at speeds variable from 500 to 3,000 r.p.m. and automatically provides for paper insertion and final parting off on com­ pletion. The precision and simplicity of this and other DOUGLAS Machines

COIL WINDING SERVICE. A special section of works is organised for winding coils to order. All winding done bv experienced operatives. Consistent accuracy is guaran­ teed. Prompt deliveries and economical charges ensured by the superiority of DOUGLAS Machines. Write for descriptive literature. AUTOMATIC COIL WINDER & ELECTRICAL EQUIPMENT CO., LTD. Winder House, Douglas Street, London, S.W.I. Telephone: Victoria 3404/7. 26 OFFICIAL APPOINTMENTS

Publicist: Mr. GARRY ALLIGHAN, Rosetti House, Hallam St., W.i. (’Phone: Welbeck 3633.) Advertising Agents: MATHER & CROWTHER, LTD., New Bridge Street, E.C.4. Stand Fitters & Decorators: GROUND FLOOR STANDS, F. STRUTT & SON, Albion Works, Albion Street, Caledonian Road, N.i. RADIOLYMPIA THEATRE, STANDS IN GALLERY, TELEVISION DEMONSTRATION ROOMS, AND GRAND STAIRCASES, OLYMPIA LTD., Kensington, London, W.14. Sign Writing : A. PERTON, 3, Beaconsfield Terrace Road, W.14. Floral Decorations: STROUD BROS., LTD., 27, Southampton Street, Covent Garden, W.C.2. Caterers: J. LYONS & CO., LTD., Cadby Hall, London, W.14. Stand Cleaners; THE MAYFAIR WINDOW CLEANING CO., LTD., ,Grantham Place, Park Lane, W.i. Exhibition Lighting Installation: BROOKS & WHITE, Electrical Engineers, 10, Maclise Road, London, W.14. Radiolympia Theatre Stage Lighting: STRAND ELECTRIC & ENGINEERING CO., LTD., 24, Floral Street, London, W.C.2. Radiolympia Theatre Organs: The organs in the Radiolympia Theatre are Hammond Organs, supplied and erected by BOOSEY & HAWKES, LTD., 295, Regent St., W.i. MUSIC The Music throughout the Exhibition will be produced by electrical reproduction from B.B.C. broadcasting or from gramophone records supplied by The Columbia Graphophone Co., Ltd., Decca Gramophone Co.,- Ltd., and The Gramophone Co., Ltd. PATENTS, TRADE MARKS AND DESIGNS. [NOTE: Inventors and others wishing to PROTECT INVENTIONS, REGISTER TRADE MARKS and DESIGNS (British and Foreign), or desirous of advice generally on patents and similar matters, may refer their enquiries to Gee & Co., Patent Agents and Trade Mark Agents (H. T. P. Gee, Patent and Trade Mark Agent, Great Britain; U.S.A. and Canadian Regd. Patent and Trade Mark Attorney; Member Radio Society of Great Britain; Assoc. Mem. Inst. Radio Engs., U.S.A., &c.), of 51 and 52, Chancery Lane, W.C.2 (2 doors from Govt. Patent Office). * Phone : Holborn 4547 & 4548. Established 190s. Ask for free Copy of Handbook," PATENTS, TRADE MARKS & DESIGNS.”]

27 Why did you come to RADIOLYMPIA

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ecause you were thinking of buying a new radio set ?—or because you wished to see the world-famous stars in action at Radiolympia’s Broadcasting Studio? In either case you came, surely, because you have seen the press advertisements or posters for RADIOLYMPIA— prepared by

MATHER & CROWTHER LTD. INCORPORATED PRACTITIONERS IN ADVERTISING BRETTENHAM HOUSE, LANCASTER PLACE, LONDON, W.C.2

Seven years ago we coined the word * Radiolympia * and prepared the advertising campaign for the first exhibition. Our efforts were so successful that we have been entrusted with this work ever since. And each year attendances have grown larger and larger. We have been successful in * selling’ Radiolympia. We can be equally successful in selling your products, too. Why not permit us to discuss this matter with you ?

28 GENERAL NOTICES.

R.M.A. Offices. The R.M.A. Enquiry Office will be found in the vestibule at the left of the Grand Hall Entrance in the Addison Walk; the Exhibitions Organiser’s Office and the Offices of the Director of the R.M.A. at the east end of the Grand Hall, Gallery ; the Offices of the Secretary of the R.M.A. at the left of the National Hall entrance in the Hammersmith Road. Press Rooms. The Press Rooms are situated in the Princes Rooms on the north side of the Grand Hall. Information Bureau. An Information Bureau for the convenience of visitors to the Exhibition is located in Stand No. 40 at the west end of the Grand Hall on the Ground Floor. Telephone Numbers: The Telephone Numbers of the offices of The Radio Manufacturers’ Association in the Olympia building are as follows : Director’s and Exhibitions Organiser’s Offices, Grand Hall, Shepherd’s Bush 3403-3407 (5 lines) ; Secretary’s Office, National Hall, Shepherd’s Bush 4338-4339 ; Press Office, Shepherd’s Bush 3763 and 3682 j Information Bureau, Shepherd’s Bush 4001. A list of the telephone numbers of the Stands of the various Exhibitors is given on page 17 of this Catalogue. Hours of Exhibition. The Exhibition will be open to the public from 11 a.m. to 10 p.m. daily. Interpreter. An interpreter is in attendance and may be found in the Information Bureau in Stand No. 40, at the west end of the Grand Hall, Ground Floor. His Services are available free of charge. Radiolympia Theatre. The Radiolympia Theatre, in which performances will be given by popular Radio Artistes, is situated in the National Hall. There will be three performances daily, at 3, 6 and 8 p.m. Admission will be by ticket obtainable in the Radiolympia Theatre Booking Office situated between the Grand and National Halls, on the Ground Floor, prices including tax, 5/9, 3/6, 2/6, 1/3 and 6d. Monday, Tuesday and Friday Matinees, 3/6, 2/6, 1/3 and 6d. The arrangements for the diffusion of sound in the Radiolympia Theatre have been carried out by the B.B.C. For fuller particulars see pages 146, 147 and 155 to 158. Television Demonstrations. Demonstrations of Television will be given nine times daily in the fourteen Television demonstration rooms in the National Hall at the following hours : 11.30 a.m., 11.50 a.m., 12.10 p.m., 4.0 p.m., 4.20 p.m., 4.40 p.m., 9.0 p.m., 9.20 p.m., 9.40 p.m. Admission is free, by means of a ticket obtainable at the Television Box Office in the National Hall. For further particulars, see pages 148 and 149. Catering. Catering by J. Lyons & Co., Ltd., caterers by appointment. Pillar Hall, Ground Floor, Grand Hall—reserved for Trocadero service. Olympia Caf6 and Grill Room, Grand Hall (right and left of Addison Walk entrance respectively). Addison Cafe, Ground Floor, National Hall—All Comer House service, Luncheons, Teas and Dinners. There are various Buffets, Chocolate and Cigar Kiosks. Music. The Music throughout the Exhibition will be produced by electrical reproduction from B.B.C. broadcasting, or from gramophone records supplied by The Columbia Graphophone Co., Ltd., Decca Gramophone Co., Ltd., and The Gramophone Co., Ltd. Cloak Rooms. Cloak Rooms will be found to the right of the entrance, in both Halls. Lost Property Office. The Lost Property Office is situated in the Gallery on the left hand side from the Grand Hall entrance. Toilet Rooms. Ladies’ Toilet Rooms are situated in the middle of the left and right hand sides of the Grand Hall, both on the Ground Floor and in the Gallery. Gentlemen’s Toilet Rooms are situated in the middle of the left and right hand sides of the Grand Hall on the Ground Floor, and on the left hand side of the Gallery. Classified Directory of Exhibits. A Directory showing the names of Exhibitors of the various types of apparatus is printed on pages 159 to 165 of this Catalogue. 29 PARTICULARS OF EXHIBITS.

GRAND HALL : GROUND FLOOR.

A. F. Bulgin & Co., Ltd. 1 Abbey Road, Barking, Essex, 1 and 64, Holborn Viaduct, E.C.l. RADIO COMPONENT SPECIALISTS. Displaying a com­ plete range of Components, including :— BULGIN Toggle and Rotary Mains Switches. BULGIN H.T. Vibrator Generators and Transformers. BULGIN Aerial Equipment and Couplers. BULGIN Fuses and Fuseholders. BULGIN H.F. and L.F. Chokes and Transformers. BULGIN Mains Plugs, Sockets and Connectors. BULGIN Signal Lamps and Fittings. BULGIN Valveholders (all types). BULGIN Wall Jacks and Remote Controls. BULGIN Short Wave Components. BULGIN Tuning, Oscillator and I.F. Coils. BULGIN Volume Controls and Resistors. BULGIN Radio Gadgets.

O Ardente Acoustic Laboratories, O C* R. H. Dent, Ltd., ^ 11-12, Pollen St., Maddox St., W.l (Public Address), 309, Oxford St., W.l (Individual Deaf Aids). PUBLIC ADDRESS SECTION.—Amplifiers of all types, 3 to 100 watts power output. Rack and Panel P.A. Systems. Microphones : Ribbon, Moving Coil and Carbon type. Loudspeakers : Moving Coil, Indoor Cabinet types and Outdoor Weatherproof types. Loud Speaker Inter-Com­ munication and Staff Locator Systems. Sound Systems for Cinemas, Theatres, Dance Halls, etc., Mixing and Control Units. Radio Tuner Units. Loud Speaker Traffic Control Systems. Relay Station and Centralised Radio Systems for Flats, Hospitals, etc. Acoustic Correction Equipment for Conference Halls, County Courts and Churches. Multi- Diffusion Systems for Restaurants and Clubs. Portable AC/DC systems for Vocalists and small bands. Bandstand Equi-Diffusion Systems for open-air orchestras and bands. Military Band Amplification Equipment. DEAF-AID SECTION.—Cinema, Theatre and Church Group Hearing Aids and full range of Individual Deaf-Aids, including CORODENTE and CRYSTADENTE the new midget valve types, small as a camera, and AURADENTE, the latest Aural Massage type. 30 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Harries Thermionics Ltd., 3 Britannia House, 233, Shaftesbury Avenue, W.G.2. 3 The Exhibits show valves and receivers covered by patents under which licences are granted by the Company. The newly released Hivac Harries All-Stage valve. The first universal standard valve for modern superheterodyne and straight receivers. A high performance six-valve and rectifier chassis using Hivac Harries All-Stage valves as marketed under licence from the company. A four-valve and rectifier superheterodyne receiver, also for Hivac Harries All-Stage valves, with an analysis of its patent position. It is made in accordance with Harries patents and docs not infringe other rights. An exhibit showing the patent history of receivers and valves, with particular reference to the Harries valves and receivers. Harries “ Geneological tree,” patent filing and records systems. A demonstration on meters of the power handling capabilities of new Hivac Harries AC/Q critical distance 60-watt tetrodes. An exhibit setting out a service for receiver manufacturers. Receivers are designed and a consultant service given. A special service for Empire and overseas manufacturers is featured.

Film Industries, Ltd., 4 60, Paddington Street, London, W.l. 4 Public Address Amplifiers, Loud Speakers and Microphones will be shown and also a typical Radio-Relay Equipment suitable for a large Institution or Hospital. The new type L.S. 8 Horn Loud Speaker Unit, price £10, will create interest. This, used in conjunction with the Company’s 70 in. all metal horn will stand 35 watts con­ tinuously or 50 watts peak, and possesses a waterproof dia­ phragm. The smaller type L.S.7 is now available with a waterproof diaphragm. The 40 in. all-welded horn is usually used in conjunction with this. Amplifiers range from the 3i watt self-contained “ Baby ” type upwards, including a 12 watt AD/DC Equipment and a special type for car work such as Police patrols. The M.2 Moving Coil Microphone is also on view.

Sterling Batteries, Limited, 5 Sterling Works, Dagenham. 5 (An Associated Company of Ismay Industries, Limited.) STERLING Primary and Secondary Batteries of all descrip­ tions. STERLING Radio Dry Batteries for Standard and Portable Sets. STERLING Special Replacement Batteries. STERLING Grid Bias Batteries. STERLING Lighting Batteries for Pocket Lamps, Torches, Cycle Lamps, etc. STERLING Bell, Telephone and Deaf-Aid Cells. STERLING Celluloid Accumulators for all types of Radio Receivers. Free Acid and Jelly Acid. STERLING Glass Accumulators. 31 N

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WORLD’S GREATEST ADVERTISING ■i , - MEDIUM ..

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32 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. fa Thomas De La Rue & Co., Ltd., /C Shernhall Street, Walthamstow, E.17. ^ The exhibit shows a comprehensive range of moulded articles used in the Radio Industry, in all proved Plastic Materials, and is designed to show the progress that has been made in the last twelve months by De La Rue in supplying the needs of Radio Manufacturers. In particular there are Radio Components Injection Moulded in Cellulose Acetate and Polystyrol Resins in addition to the. more familiar Pressure Moulded articles in Phenol Formalde­ hyde and Urea, and a range of large Moulded Radio Cabinets produced by us for well-known Radio Set Manufacturers. 7 “The Wireless World” 7 “ The Wireless Engineer,” Iliffe & Sons Ltd., Dorset House, Stamford Street, London, S.E.l. Telephone : Waterloo 3333 (50 lines). Telegrams : “ Ethaworld . Sedist London.” “ Experiwyr Sedist London.” “ THE WIRELESS WORLD,” every Friday, price fourpence. A practical radio and television journal for the wireless amateur, giving advance information about new developments, explanations of wireless theory and practice, designs and working details for the construction of modern receivers, illustrated test reports on commercial sets, components and accessories “ THE WIRELESS ENGINEER,” published monthly, price two shillings and sixpence net. The journal of Radio Research and Progress. A Selection of Wireless Books, including “ Wireless Servicing Manual,” by W. T. Cocking; “ Foundations of Wireless,” by A. L. Soweerby, M.Sc. ; “ Handbook of Technical Instruction for Wireless Telegraphists,” by H. M. Dowsett, M.I.E.E., F.Inst.P., M.Inst.P.E. ; “Radio Data Charts,” by R. T. Beatty, M.A., D.Sc. ; “ The Elementary Principles of Wireless Telegraphy and Telephony,” by R. D. Bangay and O. F. Brown, B.Sc. ; “ Dictionary of Wireless Technical Terms,” compiled by S. O. Pearson, B.Sc., A.M.I.E.E. Orders may be placed for “ THE WIRELESS WORLD ” Diary, 1938. Price Is. 6d. Q The New Era Publishing Co., Ltd., C ^ 12-14, Newton Street, Holborn, W.C.2. Visitors are cordially invited to inspect the books on this stand ; they will not be solicited to order or to buy, but every facility for leisurely examination will be given. The NEW ERA exhibits include volumes at attractively low prices, viz. : RADIO UPKEEP AND REPAIRS ; RADIO RECEIVING SERVICES ; A WIRELESS MANUAL and a GRAMOPHONE HANDBOOK; TELEVISION TO-DAY AND TO-MORROW ; and THE ELECTRICAL EDUCATOR which presents sound teaching on every branch of Radio development. TUNING IN WITHOUT TEARS is offered to those who want to understand their wireless without struggling with any technicalities. These NEW ERA publications include specialist books for every profession, trade and craft, while the NEW ERA terms of immediate delivery of the book or books, payment for them being made later on, out of income, will appeal to everyone forming a library of specialist, scientific and other volumes. 33 EVERY WEEK PRACTICAL AND AMATEUR WIRELESS is the leading and authoritative journal for home constructors. Deals with every branch of wireless and television. The entire contents are essentially practical and cater for the non­ technical amateur as well as the more serious ex­ perimenter. All PRACTICAL AND AMATEUR WIRELESS receivers are guaranteed to function. Readers’ queries are answered free.

Mr. F. J. CAMM and Technical Staff will be in attendance at Stand No. 10. Many of the original receivers will be on view. If you want to know i about the very latest ideas in radio construction, components and tele­ vision, be sure to meet Mr. F. J. 'W PgACT.CfllTri i CAMM, Editor of PRACTICAL AND AMATEUR WIRELESS on Stand No. 10. „ JrJ.Camm's UMITflH THIS WEEK’S ENLARGED mnf SHOW NUMBER SB IS ON SALE AT STAND No. 10. See these i«arr PRACTICAL BOOKS at STAND No. 10. practical TELEVISION AND SHORT - WAVE HANDBOOKS. 3 WIRELESS CONSTRUCTOR S ENCYCLO­ r “ PAEDIA. EVERYMAN'S WIRELESS BOOK. HOME MECHANIC ENCYCLOPAEDIA. WIRELESS COILS. CHOKES and TRANS­ FORMERS, and How to Make Them. " HOME MECHANIC " series of prac- LWireless tical handbooks. T ▼ and PRACTICAL TELEVISION THE OUTLINE OF WIRELESS. THE MATHEMATICS OF WIRELESS. FIFTY TESTED WIRELESS CIRCUITS. 0/ all Newsagents and Bookstalls, or by post 4d. from the Publisher, George NeWnes, Ltd., 8-11, Southampton St., Strand, London, W.C.2.

George Newnes, Ltd. 34 ; Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

9 British Railways. 9 BRITISH RAILWAYS at your service here. Information is available regarding the return of all exhibits. Experienced Railway Representatives are in attendance for Goods and Passenger Train enquiries. IT IS QUICKER TO TRAVEL BY RAIL.

| A George Newnes, Limited, 1 A Tower House, Southampton Street, Strand, W.C.2. ^ PRACTICAL & AMATEUR WIRELESS.—Every Wednes­ day, 3d. Special Enlarged Exhibition Number. The authoritative journal for home constructors. Deals with every branch of wireless and television. The entire contents are essentially practical and cater for the non-technical amateur as well as for the more serious experimenter. All Practical and Amateur Wireless receivers are guaranteed to function in the manner claimed under Free Advice Guarantee. The Editor and Technical Staff will be in attendance. Many of the original receivers will be on view. PRACTICAL MECHANICS, 6d. monthly. A fascinating journal, dealing with every branch of modem science, inven­ tion, and mechanics. Specially appeals also to the home mechanic, model maker, etc. PRACTICAL MOTORIST, 3d. weekly. The up-to-date weekly for every owner-driver. Contains a wealth of informa­ tion on the upkeep and overhaul of every make of car, touring, etc. THE CYCLIST, 2d. every Wednesday. The new journal for every cyclist. ELECTRICAL ENGINEER, 6d. weekly. The modem magazine of electrical progress. BLUE PRINT SERVICE. FuU range of Blue Prints will be on sale ; the service covers every type of receiver. TECHNICAL BOOKS. A full range of technical books will be on sale, including F. J. Camm’s famous series of volumes : 9 - “ Television and Short-Wave Handbook,” “ Wireless Con­ structors Encyclopaedia,” “ Everyman’s Wireless Book,” “ Home Mechanics’ Encyclopaedia,” “ Practical Motorists’ Encyclopaedia,” “ Every Cyclist’s Handbook,” and the “ Home Mechanics’ ” series of practical handbooks. See also Ralph Stranger’s Wireless Library. Other popular wire­ less volumes include “ The Outline of Wireless,” “ Wireless Step by Step,” “ The Mathematics of Wireless,” “ Fifty Tested Wireless Circuits,»

If MST10MEMTS i

•;

f :

made in 66stall@y" HIGH RESISTANCE STEEL TO Joseph Sa^key $ Sons J BILSTON, England.

London•• 168 Regent Street W.i.

36 'and No. Grand Hall, Ground Floor. Stand No. IUM1MII

Haynes Radio Ltd., Queensway, Enfield, Middlesex. 11 Apparatus of the quality receiver class is displayed and includes straight receiver chassis embodying iron core H.F. couplings and generous 6-watt and 14-watt amplifiers. These are exhibited also as table receivers and complete radio-gramo­ phones. Receivers include the television range and at this stand will also be found complete television equipment. The various sections comprising the complete television receiver are offered separately either as components or as finished unit chassis. Among components exhibited are mains transformers, chokes, output transformers, microphones and loud speakers.

IT The Amalgamated Press, Ltd., IT JL The Fieetway House, Farringdon Street, E.G.4. Among the attractive features on Stand No. 13 are original models of sets designed by John Scott-Taggart, Britain’s leading set designer. Descriptions of his receivers appear exclusively in “ Popular Wireless ” and achieve enormous popularity among home constructors. John Scott-Taggart’s last great success was the S.T.800, an amazing all-waver which is still being built after having created such an enormous demand for the component parts that trade stocks were wiped right out and manufacturers had to keep their factories going all night and through the week-ends in order to keep pace with orders. An entirely new Scott-Taggart set is described in the current issues of POPULAR WIRELESS and TELEVISION TIMES and you can inspect his own original model of it on Stand 13. In addition there are several other very interesting receivers which you can examine at your leisure together with some historic television apparatus illustrating the pioneer work done by POPULAR WIRELESS whose Research Laboratories produced some of the first practical cathode-ray television receiving apparatus.

1 A Gambrell Electrical Equipment * Company Limited. 14 3, St. James’s Square, London, S.W.l. The new Gambrell 7-valve All-wave Broadcast Receiver. Gambrell Portable Amplifying Equipment.

Texaloom Radio, Ltd., 15 806, High Road, Tottenham, London, N.X7. 15 Modern Radio Furniture incorporating the latest All-Wave receivers. “ Radio Bookcase,” 13 guineas ; “ Texaloom Console,” 13i guineas ; “ Combination Sideboard and Bookcase,” 16£ guineas ; “ Radio Cocktail Cabinet,” 16i guineas; and “ Utility Console,” 15 guineas. A Radiogram at 16 guineas and an Automatic Record Changing Radiogram at 22 guineas. These models available for A.C. or A.C./D.C. Mains and Battery operations, in colours of Green or Gold. 37 ' : 1

: total to Zfle (l^adto ■ o contractors ■ . • ): y^l/lauLa^iacturers <=d-ssoelation (IQ24-1937) ;

:■ ancd designers an d ladders to all the

tons ut Jdondi : ortnct^al (dycltlttt on and : : the (provinces^ we are at a 9 position to ) i jJ^itrnts l des tejns an d estimates ^without f olltaaiton ass, ortcjuial and f ) i0*0 com wetittve i EXHIBITION STANDS

f. STRUTT & SUN

ALBION WORKS • ALBION STREET KING’S CROSS • N-l TELEPHONE • TERMINUS 5449

38 ?

Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

D.M. Davies Woodwork, 16 Trading Estate, Slough, Bucks. 16 Telephone : Slough 316 (3 lines). Telegrams : Davies Slough 316. Manufacturers of accurately machined woodwork for the Wire­ less, Gramophone, Motor Car, Ship Furnishing and Cabinet Trades. Contractors to the largest Radio Manufacturers.

1 7 The Benjamin Electric, Ltd., 1 7 “ Brantwood Works, Tariff Rd., Tottenham, London, N.17--“- ■ LOUDSPEAKERS (manufactured by the Benjamin Electric Ltd., under Magnavox Patents), comprising :— 1. “ DUODE ” (Regd.) Model “33” with double voice coil construction. 2. Model “ 66.” 3. Projection Model for P.A. Work. 4. Whistle Filter. 5. A.C. Field Supply Kit. 6. Speakers in various types for manufacturers’ equipment. BENJAMIN DOUBLE-PLATE VALVEHOLDERS. Chassis-mounting Valveholders of all types, including Standard English, American and Octal.

Portadyne Radio, 18 Portadyne Works, Gorst Rd., North Acton, N.W.10. 18 The range of Portadyne Models consist of an All-Wave A.C. Superhet (Model A.58) and A.C./D.C. equivalent, an All- Wave Battery Superhet (Model B.48),an inexpensive All-Wave 3-Valve Battery Set and four Radiogramophones. The A.58—a 5-Valve A.C. Superheterodyne—incorporates eight tuned circuits and covers three bands—16.5—50, 200— 600, 700—2,100. The cabinet, of most pleasing design, is finished in two tones of walnut and incorporates the Portadyne “ Rotomatic ” Tuning Scale. This is an entirely new idea in simple tuning. A large and clear scale is devoted to each band and as the wave-change switch is rotated the appropriate; scale appears. On the long and medium bands the names of stations are in alphabetical order. The A.58 retails at 11 guineas. The B.48 is a 4-Valve Battery Superheterodyne incorporating seven tuned circuits and covering 16—48, 200—560 and 800— 2,000 metres. The cabinet is of the horizontal type and is most distinctive. A large aeroplane type scale is used. The retail price of this receiver is £9 17s. 6d. The 3-Valve Battery Set, as with all other Portadyne Models, covers the three wave-bands, and is housed in a most attractive walnut cabinet. The four Radiograms consist of an A.C. Manual Operated Model (22 guineas), an A.C. Automatic Model (29 guineas), an A.C./D.C. Manual Operated Model (23 guineas) and an A.C./ D.C. Automatic Model (30 guineas). All models cover three wave-bands and a special negative feed back circuit is incor­ porated. The cabinet, finished in figured walnut, is very hand­ some in appearance, the dimensions being 32 ins. high by 29 ins. wide by 17i ins. deep. Extension speaker sockets are fitted to the Radiograms and Table Models, the latter also having sockets for pick-up. 39 IT’S IN the " Daily Herald ”

*

ALL THE NEWS OF COURSE-truthful impressions of the events that are shaping the destinies of nations and up-to-the-minute reports of all home events of importance and general interest.

A PAGE OF PICTURES—which is acknowledged as the brightest and best produced page in daily journalism and FEATURES by the ■ finest team of special writers full of intense interest for the whole family. ' i ★ HANNEN SWAFFER speaks his mind fearlessly on important topics of the day. ! ★ H. V. MORTON'S brilliant descriptive writings appear from time to time. i ★ TEMPLEGATE on racing. : ★ T. H. WISDOM on motoring and other celebrated sporting writers are at the top of their form.

■ ★ P. L. MANNOCK appraises the film world. ★ MARY GRACE discusses clothes and everything of interest for women on the famous women’s page. ★ BOBBY BEAR the star of the Children’s Corner. ★ “KUKLOS” gives a guiding hand to tens of thousands of cyclists. ★ RICHARD SUDELL provides the last word in gardening. ★ ROGER PIPPETT surveys the world of books. ★ DOUGLAS WALTERS discusses Radio : and an unsurpassed ^10,000 Free Family Insurance. In EVERY way you will find the “ Daily Herald ” the ideal family newspaper.

READ BY OVER TWO MILLION FAMILIES DAILY FOR OVER FOUR YEARS.

40 s = s Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

2Q W. T. Henley’s Telegraph Works 2Q Co., Ltd., Holborn Viaduct, London, E.C.l. SOLON ELECTRIC SOLDERING IRONS. (U.K. Patent Nos. 243928 and 417077 ; other patents pending. Regd. Nos. 784319 Model approved by the Hydro Electric Power Commission of Canada—No. 4111.) : Displaying a complete range of SOLON Electric Soldering Irons for standard voltages. Domestic Model (65 watts) and Industrial Models to Home Office requirements (65, 125 and 240 watts). The new 125-watt iron with round pencil point bit is being specially featured. Also SOLON RESIN CORED SOLDER. In sixpenny reels and in 1 lb. and 7 lb. cartons. SPECIAL SLIDE-BACK CONNECTING WIRES, needing no cutter for stripping back the insulation from the ends ; made specially for radio set connections. Flexible Cords and other wires for Radio work.

Ferranti, Limited, 21 Hollinwood, Lancashire. 21 Without measurement, progress in any branch of scientific endeavour is impossible. FERRANTI, LTD., who have engaged in the design and manufacture of Measuring Instru­ ments for general electrical purposes since 1884, realising the great importance of this in connection with Radio develop­ ment, have made available high-grade Electrical Measuring Instruments now known all over the world as FERRANTI RADIO METERS. A complete range of Ferranti Radio Measuring Instruments is available, including models suitable for Direct Current measurements, for ordinary Alternating Current mains measurements, for measurements of Audio Frequency Supplies, as well as types for use in Radio Frequency circuits.

The Plessey Go., Ltd., 22 56, Vicarage Lane, Ilford, Essex. 22 Radio Components for use by Receiver and Radiogramophone Manufacturers only. Ganged Condensers, Loud Speakers, Electrolytic Condensers, Condenser Drives, Switches, Variable Resistances, Trimmer Condensers, Valve Holders, Yaxley Switches, Chokes, Trans­ formers. 41 i CELESTION

LOUDSPEAKERS

STAND NO.

CELESTION LIMITED, KINGSTON-ON-THAMES. Telephones : Kingston 56S6-7-8. Telegrams : “Celestion” Kingston-on-Thames.

Sole Distributor and Service Agent to the WHOLESALE and RETAIL Trades : CYRIL FRENCH, 29, HIGH STREET, HAMPTON WICK. Telephone : Kingston 2240.

42 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. 23 “Eddystone” Radio 23 Stratton & Co., Ltd •I Eddystone Works, Bromsgrove St., Birmingham, 5. On the “ Eddystone ” Stand is a comprehensive range of Short Wave and All Wave Receivers for Home and Overseas. Battery and A.C. Models, including a new A.C. All Wave Console. In all models a high standard of specialised craftsmanship is rigidly maintained. An extensive range of Short and Ultra Short Wave Receiving, Transmitting and Television components for Manufacturers and Home Constructors. This includes Low-loss Coils, High Frequency Chokes, Variable Condensers, Valve Holders, I.F. Transformers, Precision Dials, Instrument Knobs, Steel 9 Apparatus Racks and Cabinets. Expert Engineers of wide practical experience will be in attend­ " ance to advise clients on the choice of short wave receivers suited to individual conditions at home and abroad. The 1937/38 range of “ Eddystone” Receivers are the outcome of 12 years’ specialisation in the manufacture of short wave equipment for use under adverse climatic conditions.

OJ. Reslo (Sound Equipment), Ltd., OA ■" 97, Hampstead Road, N.W.l. w I Public Address and Power Type Loud Speakers. Aluminium Horns, 42 in. and 72 in. Various types Dynamic and Carbon Microphones. Microphone Input Transformers. Self-locking Microphone Stands.

F. C. Heayberd & Go •J 25 10, Finsbury Street, London, E.G.2. Battery Chargers incorporating metal rectifiers form the main feature of the display of F. C. Heayberd & Co. The range covers a very wide field, from small 2-volt .5-amp. Units suitable for charging home accumulators to large multi-circuit models designed for service stations dealing with many hun­ dreds of batteries. A full range of Transformers and Chokes suitable for all branches of radio working and also for tele­ vision apparatus are also shown. Mains Units suitable for both A.C. and D.C. operation are displayed.

Gelestion, Limited, 26 London Road, Kingston-on-Thames. 26 Exhibit a comprehensive range of Moving Coil Loud Speakers of both Energised and Permanent Magnet types, 5 to 18 inches diameter, embodying all the latest advances in the technique of sound reproduction. The requirements of set manufacturers are given special atten ion and the display includes chassis models constructed and matched to meet individual requirements. The Cabinet and Chassis models shown for domestic use and public address work are equipped for adaptation to all classes of output. 43 SIGNS, SHOWCARDS, POSTERS, OUTDOOR PUBLICITY,

CUT-OUTS, Etc.

3.BEAC0M$FIELD TERRACE R? KENSINGTON W. 14.

44 Stand No. Gr/nd Hall, Ground Floor. Stand No. Memoranda. 07 The High Vacuum Valve Co., Ltd., syj ■ 113-117, Farringdon Road, London, E.G.l. £ i f A complete range of Battery and Mains Valves. Of special interest are :— HIVAC MIDGET VALVES specially designed for Deaf Aid, ( and Pocket Radio, and for Police and Military use. HIVAC SHORT-WAVE VALVES specially designed for short­ wave reception, fitted with ceramic bases. HIVAC HARRIES BEAM POWER TETRODES, including the new AC/Q, a valve capable of delivering 60 watts when operated in push-pull. HIVAC HARRIES ALL-STAGE VALVE, a new and revolu­ tionary valve designed to provide in one valve all the desired characteristics necessary for operation in all stages of a multi­ i valve receiver.

Aerialite Ltd •J 28 Castle Works, Stalybridge. 28 Aerialite Aerial Quipment is recognised as the best obtainable. Aerial Wire. No Mast-Type Aerials. Earth Tubes. Fixing Brackets. Motor Car Aerials are included in this range. ASHTON Cables and Flibles supplied in coils and drums for all purposes. Dry Batteries. Aerialite Heavy Duty 120-v. retail 4s. lid. Percolite I20-v. retail 5s. 6d. ; also a full range of Cycle Batteries, Torch Batteries, etc., all packed in attractive counter displays. OQ Partridge, Wilson & Co., Ltd., OQ Davenset Works, Leicester, and 167, Shaftesbury Avenue, London, W.C.2. The comprehensive range of Davenset Battery Chargers for A.C. and D.C. Mains, together with Davenset Accessory Equip­ ment for the efficient battery charging station will be exhibited on this Stand. Magnetic overload protection, Moving Coil Meters, totally enclosed Rotary Packet Switches are Davenset features and their advantages will be demonstrated by chargers actually working on the Stand. The popular M.G.C. series, which covers a wide range of require­ ments, will be seen. Prices of this series are from 14 gns. for the M.G.C.3, having an output of 30 volts with three circuits, of 2, 4 and 6 amps. The Starter Charger, having an output of 75 volts with two circuits of 6 and 10 amps., is ideal for Starter Battery work and sells'at £30. There is also the H.T.5, expressly designed for the trader with a continual load of L.T. and H.T. cells. The output is 150 volts, and there are four circuits of 1 amp., and one circuit of 2 amps. The price of this charger is £40. The ever-popular Garage Charger, which statistics prove has been sold in greater numbers than any other charger, has an output of 6 amps, at 25 volts, and sells at the low figure of 9 gns. D.C. Chargers for Direct Current will be shown. In the Accessory Section will be shown Cell Testing Voltmeters, Hydrometers, Non-corrosive Battery Clips and Traders’ Shop Signs. SPECIAL NEWS. A Shop Sign is given free with every Davenset Battery Charger purchased. The electrically illuminated Davensign, sold at 58s. 6d., nett trade, is given free to all purchasers of charging equipment over 16 gns. 45 :

v

i STRAKER BROTHERS LIMITED

THE BISHOPSGATE PIRESS ; PRINTERS & STATIONERS !

r I

LETTERPRESS PRINTING

LITHOGRAPHY

STATIONERY

ACCOUNT BOOKS LOOSE LEAF BOOKS

PRINTERS OF THIS CATALOGUE INQUIRIES INVITED

194-200, BISHOPSGATE, LONDON, E.C.2 TELEPHONE: BISHOPSGATE 2444 (4 LINES)

TELECRAIiSi "STRAKER LONDON"

46 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

The Automatic Coil Winder & 30 Electrical Equipment Co., Ltd., Winder House, Douglas Street, London, S.W.l. Avo Capacity Meter, £23. Model 7 Avometer, £16 16s. Resistance Range Extension Unit for above, 10s. Universal Avometer, £13 13s. Avo Valve Tester, £11 11s. Extra Panel for above, if required, £2 2s. D.C. Avometer, £9 9s. Avo Oscillator. Universal Avominor, £5 10s. D.C. Avominor, £2 5s. Avo Exposure Meter, £3 3s. Avo Light Meter, £2 5s. AvoDapter, £1 7s. Smethurst High-Light Exposure Meter, £4 4s. “AVO” Testing Accessories, 2s. 6d. “RADIO SERVICING SIMPLIFIED.” A comprehensive textbook. 6th edition. Revised and enlarged. COIL WINDING MACHINES. “ Douglas ” Fully-automatic Multi-Winder, with paper inserter.

Siemens Electric Lamps and 31 Supplies, Ltd., 31 38 & 39, Upper Thames Street, London, E.C.4. FULL O’POWER RADIO BATTERIES. This Exhibit comprises a complete range of sizes and types for all Battery Operated Radio Receivers. Cadet (Single Capacity) Series, 6/7 m/a discharge. Special (Super) Series, 8/10 m/a discharge. Power (Triple Capacity) Series, 10/20 m/a discharge. Super Radio (Extra Large Capacity) Series, 15/30 m/a discharge. Double Capacity and Special Replacement Types for Portables, Transportables, Miniature and Kit Sets. Grid Bias Cells and Batteries. Full O’Power Dry Cells. Full O’Power Pocket, Torch and Box Batteries. L.T. Accumulators, Glass Cell Type. 47 t i Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. : OO The Chloride Electrical Storage 'jy ^ Company, Ltd., Exide Works, Clifton Junction, Nr. Manchester. Following the Exide “ Mass ” type low-tension cell incorporating the visible charge indicator, a new range of Exide “ Hycap ” accumulators, specially designed to meet the demands of high-powered modem radio receivers, was introduced. This new range, like its predecessors, has proved an unqualified success, and is again on view on the Exide Stand (No. 32) together with a comprehensive display of other Exide and Drydex batteries. Of particular interest this year are the Exide unspillable cells, on which there is a size and type to fit practically every well- known portable receiver, and which bear on their labels details of the receivers for which they are suitable. In addition a complete range of special unspillable low-tension cells for Midget Receivers has been introduced and will be on view on the same stand. Continuing the policy of having available a suitable H.T. battery for every Radio Receiver, Drydex have augmented : their range to cover all latest model wireless sets, and in addition offer alternative batteries for a number of popular sets. The use of cardboard sleeves to protect batteries in transit has been extended, as also has the practice of showing the battery type number and price on the ends of the cartons— a great convenience to the trade.

Complete news of Radio

In the matters appertaining to wireless broadcasting The Times keeps its readers fully informed. Apart from the complete information given of the daily pro­ grammes, the descriptions of special outside broadcasts and critical reviews of broadcast drama, The Times contains authoritative reports of every technical development and of all matters concerned with the administration of broadcasting.

Read

THE M TIMES

48 ' Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. Vidor, Ltd., 33 West Street, Erith, Kent. 33 Telephone : Erith 3080 (Private Branch Exchange), 10 lines. Telegrams : Vidor, Erith. BATTERIES.—Heavy Duty—Standard—Super Capacity— Replacement. Vidor have maintained their reputation for progressive enterprise by the reduction in price of the Heavy Duty 120-v. battery from 7s. 6d. to 5s. The Vidor Heavy Duty battery is the only battery Officially Approved and Recommended by the Wireless Retailers’ Association. There is now a battery for every possible requirement in the Vidor range. The same supercharged manufacturing principles are employed on the Vidor Lighting batteries, and the High Duty Lighting batteries as on the Radio batteries. To meet the needs of receivers requiring just that little extra in the way of power, the new Super Capacity range has been introduced. ALL-WAVE SUPERHETERODYNE RECEIVERS. Model CN.275.—Five-valve All-wave Superheterodyne receiver for Battery operation, with separate triode oscillator and hexode frequency changer, pentode I.F., double diode triode second detector. A.V.C. and L.F. amplifier, pentode output. High flux density moving-coil speaker. Wave-ranges 15 to 51, 50 to 180, 175 to 580, 750 to 2,100 metres. Fitted in modern cabinet of exclusive design. Price 8 gns., excluding battery and accumulator. Model CN.277.—Five-valve All-wave Superheterodyne receiver for A.C. mains operation with triode hexode frequency changer, variable mu pentode I.F. double diode detector and A.V.C. output pentode giving 3 watts undistorted output. Wave- ranges 13.5 to 51, 50 to 180, 175 to 580, 750 to 2,000 metres. Cabinet similar to Model CN.275, Price 9 guineas. Model CN.284.—Similar to CN.277, but for use on A.C. or D.C. mains. Price 10 guineas. ALL-WAVE RECEIVERS. Model CN.268.—Three-valve, Four-band, Band-pass battery operated Receiver with pentode output. Wave-ranges 13.5 to 48.5, 75 to 210, 200 to 550 and 900 to 2,100 metres. Two-tone walnut cabinet. Price, with batteries, £8 2s. 6d. Model CN.269.—Four-valve (including rectifier) Four Band Band-pass Receiver for operation on either A.C. or D.C. mains. Wave-ranges as Model CN.268. Price £9 7s. 6d. Model CN.278.—Three-valve, Three-band Battery operated receiver. Wave-ranges 16 to 50, 200 to 550 and 800 to 2,000 metres. Fitted in Walnut Cabinet of exclusive design. Price, excluding batteries, £5 19s. 6d. Model CN.279.—A similar receiver to the Model CN.278 but designed for A.C. mains operation. Price £6 19s. 6d. PORTABLE RECEIVER (SUITCASE). Model CN.272.—Size only lOi ins. by 11 ins. by 7 ins. Weighs only 16 lbs. Completely enclosed. Permanent magnet moving- coil speaker. Case covered in black leatherette. Ivory coloured floodlit scale and control knobs. Price, complete with special battery and accumulator, £6 19s. 6d. BATTERY RECEIVER (FOR MEDIUM AND LONG WAVE RECEPTION ONLY.) Model CN.273.—A Three-valve Battery operated Receiver, employing Band-pass input and three tuned circuits. Cabinet of distinctive two-toned walnut. Price, exclusive of battery and accumulator, £5 12s. 6d. 49 C Stand No. Grand HaUj, Ground Floor. Stand No. Memo ianoa.

'1A Beethoven Radio Limited, *24 ■ Chase Road, North Acton, London, N.W.10. H A full range of New Season’s models comprises Portable and Transportable Battery Sets, Portable Mains Sets, and Super­ heterodyne instruments, including All-wave A.C./D.C. models ranging from 6 guineas to 26 guineas. Special attention is directed to the Cabinet work which plays so important a part in the appearance of a Radio set. These cabinets are designed and made in our own Factory by Acousticians and are guaranteed to give the maximum quality, purity and volume, without vibration or distortion. BATTERY RECEIVERS. MODEL P.101.—“ THE * BABY ’ PORTABLE ‘ALL OCCASION ’ ’^RADIO. The smallest and lightest portable, no larger than a box camera. An ideal set for use at Home, in the Car or on Holiday. Weight 10 lb. Wave range, 200-550 and 900-2,000 m. MODEL P.202.—THE SUPER “ BABY ” MOVING COIL SPEAKER fitted with SignalJTight calibrated in Station Names. Four full size Valves,^80-volt H.T. Wave range, Medium 200-550 metres, Long 950-2,000 metres. MODEL P.107.—THE SUPER MINOR SUITCASE PORTABLE fitted with Moving Coil Speaker. Interior panelling of Walnut and Sycamore, chromium plated fittings. Signal Light indicator—calibrated in Station Names—108- volt H.T. Wave range, 200-550 and 900-2,000 m. :■: MODEL B.848.—All-WAVE SUPERHET BATTERY TRANSPORTABLE. All Home and Foreign Stations including short wave can be ! received without any external aerial or earth. 7-stage Superhet— Own Frame Aerial—Illuminated Scale calibrated in Station Names—Triple Colour Wave-band Indication—120 volt H.T. Wave range, 16-50 ; 200-550 ; 900-2,000 m. i MAINS RECEIVERS. MODEL A.D. 303.—SUPERHET A.C./D.C. ALL-WAVE PORTABLE. No aerial or earth required, even for short waves. 8-stage Super­ het—Automatic Volume Control—Slow Motion Drive— Size only lOi ins. by i0£ ins. by 6 ins. Wave range, 16-50; 200-550; 900-2,000 m. MODEL A.D. 404.—SUPERHET A.C./D.C. ALL-WAVE TRANSPORTABLE. No aerial or earth required, even for short waves. Fitted with self-contained Frame Aerial—A.C. or D.C.—Cabinet of highly figured Walnut—8-stage Superhet—Automatic Tone Compensation—A.V.C.—Sloping Scale Desk—Illuminated Scale calibrated in Station Names—Colour Wave-band Indication—Wave range, 16-50 ; 200-550; 900-2,000 m. MODEL A.C. 852.—TWIN SPEAKER ALL-WAVE SUPER­ HET. Eight-stage Superheterodyne—2 Moving Coil Loud Speakers— Manual and Automatic Tone Compensation—Delayed A.V.C. Triple Colour Wave-band Indication—Sloping Scale for easy viewing—Wave range, 16-50; 200-550 ; 900-2,000 m. MODEL R.G. 938.—TWIN SPEAKER ALL-WAVE RADIO GRAMOPHONE. Automatic Stop—Powerful 8-stage Superhet—8 watts Output— The Cabinet is of modem style. Figured and Straight Grained French Walnut. 50 Stand No. Gra^d Hall, Ground .Floor. Stand No. Memoranda.

'JC Halcyon Radio, Limited, 2C Sterling Works, Dagenham, Essex. Halcyon Radio, Ltd., Sterling Works, Dagenham, Essex, exhibiting Radio Receivers, Radiograms and Auto Radio­ grams, ranging in price from Battery Model at £5 19s. 6d. to Radiogram with Automatic Changer at 37 guineas. Also Television (Demonstration Room No. 13). All-wave A.C. Table Models with Flywheel Tuning, Patent No. 447—559, 5-valve 8-stage Superheterodyne Model A.581, 15 guineas, Model A.5820, 12£ guineas. Universal Table Models with Flywheel Tuning, Patented, 6-valve 8-stage Superheterodyne Model U.6801, 16 guineas. 5-valve, 8-stage, Superheterodyne Model U.5820, 13 guineas. Transportable A.C./D.C. (without Flywheel Tuning), 6 valves, 1(H guineas. Superheterodyne All-Wave A.C./D.C. Receiver, Model U.573, 5 valves, 8 guineas. Medium and Long Band Receiver, A.C./D.C., 4 valves, Model U.341, £6 19s. 6d. Battery Receivers with Flywheel Tuning (Patented), 6-valve, 9-stage Superheterodyne, Model B.691, 14 guineas. Three valves TRF. with band-pass, Model B.333, £5 19s. 6d. All without batteries. Radiograms with Flywheel Tuning (Patented) 5-valve, All-wave, Superheterodyne, Model RG/A.581, 25 guineas. Six-valve Universal Model RG/U. 6801, 27 guineas. Eight Record Changer Model RGC/A.581, 35 guineas. Universal Model RGC/U.6801, 37 guineas. Television Receivers, Models T.100 and T.101. Clear sharp and well defined pictures. Simple to handle. Installed and maintained in working order, under guarantee for 12 months from date of purchase. Model T.100 fitted with All-wave Receiver, 70 guineas. Model T.101, Sound and Television Wave Band only, 55 guineas.

'If* British Tungsram Radio Works, Ltd., 2ft West Road, Tottenham, N.17. TUNGSRAM are exhibiting a selection of valves from the comprehensive range available. TUNGSRAM were one of the first British Valve Manufacturers to introduce the American type of valve in this country, and have available a complete range of International type valves with octal bases. TUNGSRAM now have available double diode high slope output pentodes for both A.C. and Universal sets, known as the DDPP4B and DDPP39 respectively. TUNGSRAM have also added a further output pentode to their battery range, a large output type known as PP225. TUNGSRAM cater for the short-wave market, and have a comprehensive range of receiving and transmitting types of valves. TUNGSRAM have also considerably improved their standard range, in structure, characteristics, efficiency, and finally, TUNGSRAM have a Technical Department, maintained for the purpose, who would be very pleased to give any technical advice or assistance either upon the question of valves or construction of radio receivers and apparatus. 3 51 02 i. GARRARD Quality Products

RECORD CHANCER

RADIO-CRAM UNIT , TYPE "A" v-W:

v Type *'A” Radio-gram Units, 63/- to 128/6

i ■

JtADlO-CRAM UNIT TYPES- Sit Type "B” - Radio-gram ! . Units, 62/6 to 87/- •» - !

•< y PICK-UP and ARM

- Send for illustrated leaflet to-day. __ i

GARRARD ENGINEERING & MANUFACTURING CO. LTD. Swindon, Wilts. 17, Grafton St., W.l Telephone: STAND No. 37 Telephone : Swindon 534 & 535 (2 lines) Regent 7596

R.3553. 62 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. The Garrard Engineering & 37 Manufacturing Co., Ltd., 37 Newcastle Street, Swindon, Wilts. GARRARD ” Automatic Record Changing Units, A.C. and Universal Types. “ GARRARD ” Radio-gram. Units, in two types ; Type A, comprising Motor mounted on rectangular plate 16 ins. by 14 ins. and fitted with either U.5 Universal Electric Motor, No. 202A, No. 201A, A.C.4 and A.C.6 Induction Electric Motors, or No. 10B and No. 30 Double Spring Motors. Type B, comprising Motor fitted with simple type plate, particularly suitable for fitting in restricted space and supplied complete with either No. 202A, A.C.4 and A.C.6 Induction Electric Motors or U.5 Universal Electric Motor. “ GARRARD ” Pick-ups. “ GARRARD ” Regd. Electric and Spring Motors for Radio- gramophones and Gramophones, comprising the following :— U.5 Universal Electric Motor. Induction Electric Motor, No. 201 A. Induction Electric Motor, No. 202A. Induction Electric Motor, A.C.4. Induction Electric Motor, A.C.6. No. 10B, Double Spring Motor. Junior B, Double Spring Motor. No. 30, Double Spring Motor. No. 12BB, Single Spring Motor. No. 20, Single Spring Motor. No. 21, Single Spring Motor. “ GARRARD ” Window Display Turntables, A.C. and Univer­ sal models in two types—Intermittent motion type (12 in. size) and continuously revolving type (10 in. and 12 in. sizes). “ GARRARD ” Display Stands for Window Display Turntables. “ GARRARD ” Main Springs and Lubricants. QQ The Telegraph Condenser Co., Ltd., 2Q Wales Farm Road, North Acton, London, W.3. Fixed Condensers of every description, including Paper, Mica, Wet Electrolytics in aluminium cans, Dry Electrolytics in cartons, metal boxes and aluminium cans, Low and High voltage electrolytic types in tubes. Non-inductive Paper Tubular Condensers and Moulded Mica Condensers, etc., for use in Radio Receivers, Amplifiers, Telephone and Telegraph circuits. High Frequency and High Voltage Smoothing Condensers for Transmitting Stations and Jelly Impregnated Condensers for Television circuits. Static Condensers for Power Factor Correction. ! Condensers and Special Units for the suppression of interference with radio reception, including types for use in vacuum cleaners, refrigerators, electric sewing machines, hair dryers, etc. Suppressor Condensers for car radio work. Special ranges of condensers for use in high temperatures incurred in the tropics. Ignition Condensers. Precision Condensers in Ceramic materials. Information Bureau, 40 The Radio Manufacturers’ Association, Astor 40 House, Aldwych, W.G.2. At this stand visitors may be given information concerning the Exhibition. An interpreter is in attendance. ; Dealers are particularly recommended to inspect the “ Radio Service Manual,” just published • by the R.M.A.—a book which should find a useful place in the Service Department of every Retailer. For further particulars, see page 124. 3 53 W • •V

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54 ■

Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

British Rola Co., Ltd., 41 Minerva Road, Park Royal, N.W. 41 Two new Rola models that are certain to attract attention this year are the F742-PM and the F1050-PM. The former is a 9£-in. diameter speaker that embodies several new features of unusual interest. In the first place it is exceptionally sensitive, possessing a flux density of 11,500 lines per square centimetre which is equal to that of the famous G12-PM. For this reason it is particularly suitable for battery set or Extension Speaker use. A new magnet material “Alnico ” is employed in its construction and it is equipped with a dust- proof, moisture-proof, metal and compound shielded trans­ former that ensures long life. At 49s. 6d. this unit represents remarkable value for money. The F1050-PM is a slightly larger model of 10-in. diameter having a flux density of 12,000 ! lines per square centimetre and a power handling capacity of 8 watts at 100 cycles. Amongst the smaller Rola speakers a new lightweight unit appears in the Rola F5B-PM. This 6| in. diameter model provides reproduction of surprisingly high quality. Of the two Rola Cabinet Extension Speakers, the Rola “ Roma ” and the Rola “ Rex,” only the latter is new since last year’s exhibition. The Rola “ Roma ” quickly became famous for its handsome design and beauty of tone. The Rola “ Rex ” which has been enthusiastically welcomed since its introduction at the beginning of the year is a de luxe model employing the same unit but housed in a really magnificent walnut cabinet, acoustically correct and furnished with a volume control, mounted in a convenient position on the front of the cabinet. Both models give exact matching with any receiver. All the Rola models which have proved so popular in the past are being continued but special mention should perhaps bev made of the giant G.12s. These are, indeed, units of unsur­ passed quality. Both energised and permanent magnet models are available having a power handling capacity of 24 watts at 100 cycles. Here is the Rola range— MODEL;F5 Energised (6f-in. diameter), 25s. MODEL F5B-PM (6§-in. diameter), 25s. MODEL F512-PM (6J-in. diameter), 27s. MODEL F520-PM (6§-in. diameter), 28s. 6d. MODEL F6K Energised (8-in. diameter), 27s. 6d. MODEL F612-PM (8-in. diameter), 29s. 6d. MODEL F620-PM (8-in. diameter), 32s. 6d. MODEL F624-PM (8-in. diameter), 35s. 6d. MODEL F7 Energised (9f-in. diameter), 35s. MODEL F720 PM (9f-in. diameter), 36s. MODEL F724 PM (9f-in. diameter), 39s. MODEL F742 PM (9|-in. diameter), 49s. 6d. MODEL F10 Energised (10-in. diameter), 37s. 6d. MODEL FI020 PM (10-in. diameter), 38s. 6d. MODEL F1024 PM (10-in. diameter), 41s. MODEL F1050-PM (10-in. diameter), 59s. MODEL 8ZAK-PM 6.5V (8-in. diameter), 23s. 6d. MODEL 8ZAK-PM 6.5U (8-in. diameter), 21s. MODEL G12 Energised (12-in. diameter), £5 5s. Od. MODELG12 PM (12-in. diameter), £5 5s Od. 65 ' r Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

AO Belling and Lee, Limited, AO ■ Cambridge Arterial Road, Enfield, Middlesex. I » Suppressors for the elimination of H.F. electrical interference picked up on the mains. Flexible Lead Suppressors, Set Lead Suppressors, Mains Filters, Appliance Plug Suppressors, Meter Board Suppressors, Line Suppressors. H.F. Mains Chokes, £ to 300 amps., Interference Suppressors for Car Radio, Double Choke and Condenser Filters, Treble Choke and Condenser Filters. 44 Eliminoise ” Anti-Interference Aerial. Screened Transmission Line. Interference Measuring Apparatus and Locators. Television Aerials, Components and Accessories and special Television Interference Suppressors. Low Loss H.F. Low Impedance Feeder. 44 Clip-on ” Pick-up for Portable Gramophones. Electrical Pick-up with and without Volume Control. Plug Top Connectors, Hoods and Low Loss Leads for Valves. Octal, High Tension (for Television) and other Valve Holders. Completely insulated Screw Terminals, lettered and plain, Television Indications, Low Loss Terminals, and Bushes for Short-wave work, Single and Twin Shrouded Plugs and Sockets for Mains, Mains Input Connectors, fused and unfused, Fuse Plugs. Flat pin Plugs and Sockets for Loud Speaker extensions, etc. (not interchangeable with mains). Twin Socket Strips, lettered. Flush Mounting Self-Bushing Sockets for plugs. Wander plugs, various types, lettered and in colours. Fuses (including 44 Mag-nickel ” Delay), and Fuseholders, “ Scrufuse,” 44 Wanderfuse,” Battery Cords, Accumulator Connectors.

AO Goodmans Industries, Limited, AO ■ ^ Lancelot Road, Wembley, Middx. ■ PUBLIC ADDRESS Loudspeakers of the horizontal Projector type, at very competitive prices will form a special feature of this Exhibit. Noteworthy is the special design of the DUPLEX HORN Loudspeaker, which gives the effect of two Speakers. The world-renowned HIGH FIDELITY AUDITORIUM Loudspeakers (10 in. and 1 in. Models) incorporating patented Dual Exponential diaphragms are again exhibited, also CABINET and BAFFLE Loudspeakers, for light Public Address work and Relay. A new ELLIPTICAL Loudspeaker, claimed to give reduced focusing of the higher frequencies will also be exhibited. ’Another release is a High Fidelity type Loudspeaker for TELEVISION RECEIVERS, fitted with a specially designed Magnet, to prevent interference with the Electron Beam inside the Cathode Ray tube. A full range of Loudspeakers for SET MANUFACTURERS, including Permanent MAGNET, ENERGISED, ELLIPTI­ CAL, TELEVISION types and HIGH FIDELITY models are available to bona fide enquirers, on request. This Firm is now fully equipped, and specialise in the manufac­ ture of PRESSED and DRAWN PARTS, AUTOMATIC and TURNED PARTS from £ in. to 1J in. They are also able to undertake mass production STOVE ENAMELLING. 56 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

A A Wingrove & Rogers, Limited, A A 188-9, Strand, London, W.C.2. ® ® Mill Lane, Old Swan, Liverpool, 13. POLAR, POLAR-N.S.F. AND WEARITE COMPONENTS. POLAR “ Bar Type ” Gang Condensers. Single air and solid dielectric Tuning Condensers. Trimmer and Short Wave Condensers. Full-vision drives, including the new dual ratio Micro Horizontal Drive. POLAR-N.S.F. Volume Controls, Resistors, Electrolytic and Tubular Condensers. WEARITE Air and iron core Coils, including the new three- range “ Triogen.” I.F. Transformers and Oscillator Coils, Power Transformers, Chokes—H.F. and H.T. smoothing, Push-pull and Rotary Switches.

British “Wireless for the Blind” 46 Fund, 46 226, Great Portland Street, London, W.l. This Fund was started on Christmas Day, 1929, by a broadcast appeal by Mr. Winston Churchill, and thanks to the generosity of the public, the assistance given by the B.B.C. (in arranging facilities for broadcast appeals), and the R.M.A. (by giving the use of a stand at each Radio Exhibition), it has been able, up to date, to distribute over 33,500 wireless sets to the blind in Great Britain and Northern Ireland ; 1,000 of these sets were provided by the R.M.A. free of charge. The Fund has therefore completed its original task of supplying wireless sets to blind persons who in 1930, had not experi­ enced the pleasure to be gained from listening-in, but the sad thing about blindness is that a large number of new cases occur every year. Moreover, the time has now come when a considerable number of worn-out sets have to be replaced. It is hoped that everybody will vist the Fund’s stand at this Exhibition, where a display is made of the different types of wireless sets which are provided for the blind.

4.7 British Television Supplies Ltd., A.7 ■ ■ 8, Charing Cross Road, London, W.C.2. 1 f Multi-valve All-wave (10 to 2,000 metres) Superheterodyne.- Receivers in chassis form and also as complete Receivers in Cabinets. The “ Little Princess ” Portable Receiver. SPECIAL HIGH-FIDELITY SOUND REPRODUCING APPARATUS. The “ H.A. Hartley Special ” Electrodynamic Loud Speaker. High Fidelity Receivers and Radiogramophones. A.F. Amplifiers for gramophone work and public address systems with various output powers. Complete receivers. Receiver chassis. Kits for Home Con­ structors. A complete service for Experimenters and Home Constructors. 57 ! ' Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

i. Gosmocord Limited, \ 1 48 Enfield, Middlesex. 48 I “ ADAGRAM.”—Playing Desks for A.C. and D.C./A.C. Mains. Prices from £3 10s. Od. each. 1 “ PICK-UPS ” of assorted types. Prices from 5s. Od. each. “ RADIO-GRAM ” Motor Units for A.C. and D.C./A.C. Mains. Prices from £2 Os. Od. each.

4Q Department of Overseas Trade, AQ ■ ^ 35, Old Queen Street, London, S.W.l. I

United Kingdom manufacturers and traders can obtain from the Department of Overseas Trade reliable commercial information relative to markets abroad. The information includes particulars of customs tariffs and regulations, commercial legislation, statistics of imports and expons, contracts open to tender, etc. Information can also be obtained from the Department relating to the demand overseas for particular goods, methods of marketing and distribution, as well as on many other matters of importance to the exporter. The Department also supplies lists of importers of various goods in overseas markets and is prepared to suggest suitable agents for United Kingdom manufacturers and merchants. Another activity of the Department is the regular publication of reports upon the economic and commercial conditions prevailing in various countries all over the world. Besides being responsible for the British Industries Fair, the Department organises all official British Sections in Exhibi­ tions, whether at home or overseas. All Standholders are invited to consult the Department’s repre­ sentative on the Stand.

Cl The British Broadcasting Corporation, Cl Broadcasting House, Portland Place, W.l. ^

EMPIRE BROADCASTING. How the six Transmissions of the B.B.C. Empire Service reach listeners in all parts of the Empire is shown by means of six displays. Each of these shows the area served, and the time at which the Transmission takes place in order to reach its appointed area during the early evening. “B.B.C. EMPIRE BROADCASTING.” Specimen copies and full particulars of the published programmes of the Empire Service are available at the Stand. See also Stand 78 on opposite side of the Main Stairway.

• i 58 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

CO Aerodyne Radio Limited, CO Tottenham, N.17.

AERODYNE RADIO present their 1938 range of Radio Receivers with the confidence and pride inspired by sound engineering ability and honest craftsmanship. Each type of Receiver is an outstanding example of striking performance and rugged reliability, all housed in cabinets that are really beautiful examples of the modern cabinet-makers’ art, planned to please the most fastidious. A high standard of tonal quality is a feature of every instrument, ensured by the use of loud speakers, specially manufactured for each individual type of instrument.

MODEL No. 285. This is an A.C. Mains Receiver, utilising the latest type of iron cored radio frequency coils and having four wavebands, viz. :—13—49m., 48— 170 m., 160—550 m., 700—2,000 m. The valve combination comprises : H.F. Pentode, Triode Detector and Pentode Output. Main features are high sensitivity and good reproduction. Undistorted Output — 3 watts.

MODEL No. 286. Is the A.C./D.C. version of the above Model No. 285. MODEL No. 290. This instrument is a 6-valve A.C. Superheterodyne, covering 16.5—50 m., 200—550 m., 700—2,000 m. The sensitivity is extremely high with low noise level, effectively demonstrating the value of an H.F. Amplifier, especially on short waves. Other features include : Magic eye tuning indicator, automatic volume control and large undistorted output.

MODEL No. 295. Is the A.C./D.C. equivalent of Model 290, the main difference being the combined double diode output Pentode, the latest Mazda achievement, rated to give 4.75 watts output.

MODEL No. 291. A 5-valve A.C. Superheterodyne, having four wave-bands : 13.5—43.5 m., 43—141 m., 180—550 m., 700—2,000 m. This is an instrument of outstanding ability on all wave-bands. Iron cored I.F. transformers are used, as on all AERODYNE superhets, properly band-passed to ensure maximum selectivity with minimum top cut. High sensitivity, output and low noise level are again predominant features.

MODEL No. 296. A 3-valve Portable Battery Receiver complete with batteries and internal aerial, really small dimensions in a new attractive type of cabinet. The sensitivity is remarkably high, due to a novel frame aerial arrangement and the 6-in. moving coil loud speaker provides astonishingly good reproduction.

MODEL No. 297. This is a 3-valve Band-Pass Battery Receiver with two wave-bands only :— 200—550 m., 800-2,000 m. A high degree of selectivity and sensitivity are achieved by the use of iron cored coils in a really attractive moderately priced Battery Receiver.

MODEL No. 298. A 4-valve A.C. Superheterodyne, covering three wave-bands :—16.5— 50 m., 50—550 m., 800—2,000 m. Valve combination comprises :— Triode Hexode, H.F. P^itode, Double Diode Pentode and directly heated rectifier. 69

Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

53 The Marconiphone Co., Ltd., 53 Radio House, 210/212, Tottenham Court Road, 64 London, W.l. 64 Telephone : Museum 4144 (11 lines). Telegrams : Marconifon, Telex, London. ALL-WAVE RADIO, RADIOGRAMOPHONES AND TELEVISION. With a range comprising over twenty models there is a Marconiphone Receiver or Radiogram for every purse and purpose. Screen-grid and superhet battery receivers, all-wave superhet table grands for A.C. and D.C. mains, all-wave A.C. and D.C.- superhet radiograms, and luxurious auto-radiograms—all designed to fill a definite need and all built to conform with the high standards established as a result of over 50 years’ radio research and experience. In this necessarily limited survey of the Marconiphone Stands it is not possible fully to describe the merits of the various models included in the 1937/8 range nor will space permit of an individual reference to every instrument exhibited. The following brief descriptions of certain of the models on view are intended merely as a guide to the general trend of Marconiphone progress. Attention is specially directed to the fact that world-wide reception is provided by practically every receiver and radiogram in the range exhibited, yet despite this almost universal provision of all-wave facilities, ease of handling and perfected musical reproduction still remain the predominant features of Marconiphone design. MARCONIPHONE TELEVISION RECEIVERS. Several Television models are exhibited on Stand No. 53 including Model 701 which combines Television and all-wave reception, Model 702 which is intended for the sound and vision reception of Television, and Model 703—the very last word in modern home entertainment providing Television, world radio and auto-gram in one instrument. MARCONIPHONE BATTERY RECEIVERS. MODEL 222.—An all-wave 4-valve battery superhet covering from 18— 2,000 metres in three wave-bands. Station named and wavelength calibrated dial. Very low battery consumption. MODEL 314.—Three-valve screen-grid battery receiver for medium and long waves offering a wide choice of programmes and real economy in running costs. MODEL 562.—Six-valve battery superhet transportable for medium and long wave reception, entirely self-contained and extremely economical in use. MARCONIPHONE ALL-WAVE TABLE GRAND SUPERHETS. MODEL 382.—An all-wave 4-valve superhet table grand for A.C. and D.C. mains. Very simple to operate, and covering three wave-bands from 16—2,000 metres. MODEL 347.—A luxury 6-valve superhet table grand for A.C. mains providing the world’s programmes on five wave-bands from 7—2,250 metres. Electronic visual tuning indicator. MODEL 559.—De-luxe 6-valve superhet table grand for A.C. mains providing unlimited programme entertainment from all parts of the world on three wave-bands from 16.5—2,000 metres. MODEL 561.—Ten-valve de-luxe superhet table grand for A.C. mains with world-wide range. Five wave-bands, electronic visual tuning indicator and all the very latest technical developments. MARCONIPHONE RADIOGRAMS AND AUTO-RADIOGRAMS. MODEL 575.—An up-to-the-minute 6-valve, three wave-band superhet radiogram with visual tuning, ample output and perfected quality of reproduction. For A.C. mains. MODEL 576.—Incorporating the same chassis as Model 575 but with automatic record-changer mechanism. MODEL 367.—De-luxe 6-valve five wave-band (7—2,250 metres) superhet auto-radiogram for world-wide reception. MODEL 563.—A luxury 10-valve five wave-band superhet auto-radiogram in a magnificent cabinet of true period design. See also Stand 64. 61 Stand No. Grand Halt., Ground Floor. Stand No. Memoranda.

The General Electric Co., Ltd., ^4 62 Magnet House, Kingsway, London, W.G.2. 62

“OSRAM” VALVES.

The “ INTERNATIONAL RANGE ” of “ Osram ” Valves is i displayed in full. This new range of indirectly heated mains valves for broadcast reception introduces a number of import­ ant changes in relation to British Valves hitherto manufac­ tured. A heater rating of 6.3 volts 0.3 amps, has been adopted for the majority of the range, giving a heater wattage of 1.9 watts as compared with 4 watts for British mains valves in the past. Reduced size of cathode enables smaller overall dimensions to be attained. The range is equally applicable to A.C. or D.C./A.C. receivers and for car radio receivers working off 6-volt or 12-volt batteries.

THE OCTAL BASE.

The OCTAL BASE incorporated in the Osram International Range is self-locating in its socket by means of a moulded key on the base. This fits into a key-way in the socket and makes the insertion of a valve simplicity itself.

Various features of the International Range form the subject of working demonstrations.

OSRAM 2-VOLT BATTERY VALVES are extensively dis­ played as well as

OSRAM VALVES FOR SPECIAL PURPOSES—Acorns, split anode magnetrons, electrometer triodes, etc.

OSRAM VALVES FOR POWER AMPLIFIERS.

DISPLAY OF WATER-COOLED TRANSMITTING VALVES.

OSRAM VALVES FOR TELEVISION.

CATHODE RAY TUBES.

THE LATEST IN TELEVISION.

62 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. A. J. Balcombe, Ltd., 55 52-58, Tabernacle Street, London, E.G.2. 55 There is no doubt that the best advertisements for ALBA Radio arc the legions of satisfied ALBA users themselves. In the train and bus, on holiday, visiting friends, on sports grounds, and other places where people meet, there the topic of conversation so often turns to radio, and—“ my ALBA, a fine reliable set.” And such advertising is all the more valuable because it is spontaneous and unsolicited. Success has been achieved by a simple, yet sound policy—a policy that ensures every penny spent going into the production of the set for the ultimate benefit of the purchaser. The first and only consideration is to produce sets that will give years of trouble-free service and to offer them at really moderate prices. If anyone should get the idea that the low ALBA prices mean that anything has been sacrificed in construction, let him look into some of the finest homes in the country— homes where quality only counts. There he will find ALBA ! Once again, for 1937-8 ALBA has provided a comprehensive selection of models that for performance, appearance and value will be unbeatable. This new range will show the way in the radio industry just as surely as our programmes of past years have always “ delivered the goods ” ! AT EASE WITH YOUR ALBA. A new slogan introducing radio’s latest sensation—the new ALBA “ armchair console.” This is as delightful a piece of furniture for the modern home as you have seen. Recline at ease in your favourite chair... move your hand slightly . . . and within your reach are the controls of a high- class all-wave radio receiver, to bring you the world’s best programmes. And this new ALBA is the equivalent of an occasional table, coffee stool or what-have-you. The radio controls are sunken so that a tray or cover can be placed on the top. Here is radio in its most ornamented and useful stage—ALBA “ arm­ chair radio ” ! Other fine receivers and radiograms to be seen on the ALBA stand include the following :— MODEL 815.—A high-class. Chassis built 5-Valve All-Wave mains Receiver at the low price of 8i guineas (A.C.) or 9 guineas (A.C./D.C.). This set has already proved itself as one of the industry’s most popular sets ever. MODEL 825.—A de luxe All-Wave Receiver incorporating many refinements not usually found in sets as low in price as 11 guineas, including an undistorted output of 8 watts. MODEL 930.—A super de luxe All-Wave Radiogram, with a 7-Valve 4-wave band circuit. Available with or without automatic record changer. One might almost describe this as “ finality in radio.” MODEL 910.—A first class All-Wave Mains Radiogram, incor­ porating a similar chassis to the 815 receiver. Amazing value at 18 guineas (A.C.) or 20 guineas (A.C./D.C.). Available with automatic record changer at 5 guineas extra. MODELS 435 AND 455.—Two battery operated Radiograms and probably the only models of their kind in Olympia. Now those without electricity in their homes can enjoy the pleasures of the combined instrument. Complete ALBA catalogue available from the stand, or from the head office, 52-58, Tabernacle Street, E.C.2. 63 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Invicta Radio Ltd., 56 Radio Works, Parkhurst Road, London, N.7. 56

INVICTA RECEIVERS AND RADIOGRAMOPHONES.

INVICTA have a comprehensive display of standard broadcast and All-wave Receivers.

A point of interest is that three of the All-wave Models incor­ porate the television sound wave-band and one of them actually tunes from 6.5 to 550 metres without a break.

All models are fitted with moving-coil speakers and models 310, 310 R.G., and 330 will give an output of 8 watts.

Manual Volume and Tone Controls are fitted to enable reproduc­ tion to be adjusted to individual tastes.

INVICTA COLOURMATIC TUNING. A special point of interest is the Invicta Colourmatic Tuning, which is ably demonstrated by an enlarged working model.

PRICES. Prices of Invicta Receiving sets range from £5 5s. Od. to 17 guineas, as follows :— Model 420 3-valve 2 wave-band Battery Receiver, £5 5s. Od. Model 340 Band-pass 3-valve 2 wave-band Battery Receiver, £6 15s. Od. Model 360 A.C. Super 2 wave-band, £1 19s. 6d. Model 300 A.C. Superhet 3 wave-band, £10 15s. Od. Model 390 Battery All - wave Superhet 3 wave-bands, £10 15s. Od. Model 400 A.C./D.C. All-wave Superhet 3 wave-bands, £11 10s. Od. Model 310 A.C. All-wave Superhet 4 wave-bands, £14 3s. 6d. Model 330 A.C. All-wave Superhet 6 wave-bands, 17 guineas. Model 310 R.G. All-wave Superhet Radiogramophone, 4 wave­ bands, 22\ guineas.

TELEVISION RECEIVERS. Two Television Sets are also on view, one for reception of the television wave-band only and one fitted with an all-wave radio chassis.

64 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

C7 The Edison Swan Electric Co., Ltd., C7 " 155, Charing Cross Road, London, W.C.2 kJ i TELEVISION.—In addition to the range of Ediswan Cathode- Ray Tubes and Mazda Television Valves, this exhibit includes a complete Television Receiving Equipment, arranged in sections so that some idea of the construction and layout of a typical Television Set can be obtained. To demonstrate the conversion of light into electrical energy—the fundamental essential in Television—a light motor, rotated by the action of a beam of light upon light sensitive cells, is shown. A large relief diagram showing the construction of a Cathode-Ray Tube gives the non-technically minded a good idea of the structure of this very interesting piece of apparatus. A multi-colour, Cathode-Ray Tube attractively shows what can be done in the matter of colour with florescent materials, and another tube with a long afterglow screen proves both intriguing and interesting. MAZDA VALVES.—Mazda Engineers have been first in the field with many new valves and some of these pioneer types are displayed along with a colour film showing modern Mazda Valves in course of production. The latest types of Mazda Valves are also exhibited. B.T.H. R.K. LOUDSPEAKERS AND HEADPHONES.— These well-known sound reproducing instruments in their latest and improved forms include the Senior A.C., Senior D.C., and Senior P.M. Models and the Minor R.K. Cabinet Model. R.K. Loudspeakers are used by many of the leading set makers and are strongly recommended for inclusion in radio and television receivers, radio-gramophones and as extension speakers. B.T.H. PICK-UPS.—The B.T.H. PezoLectric Pick-up which operates on the piezo-electric principle represents still further progress in pick-up design and construction. The 1937/8 model reaches a high standard of efficiency in the electric reproduction of music from gramophone records. Those who require a really high quality pick-up at a very reasonable price will be interested in the B.T.H. Minor Pick-up which sells complete with self-contained volume control at 17s. 6d. EDISWAN TUNGAR RADIO BATTERY CHARGERS.— These famous chargers, which represent a high standard of efficiency, are in extensive use throughout the country by ( private individuals, battery charging stations, and large organisations such as the important railway companies. They are quite simple to operate and call for very little attention. There are no moving parts and the only items which call for replacement are the valves which are robust and give very long service. EDISWAN “ EXTRA-LIFE ” ACCUMULATORS have been j developed as a result of long and extensive experience, and have been specially designed for high or low discharge rates. The full range is exhibited and includes models embodying the patented “ Chargetime ” device which gives direct indication of the condition of the battery, showing at a glance when it is necessary to recharge. 65 THOSE WHO

KNOW BEST

read the EVENING STANDARD

It helps them

to know best in News, Sport, Fashion,

Social Affairs, Finance,

Amusements and Books

DO YOU KNOW BEST ? ♦ Hr,' *1

Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. I CQ McMichael Radio, Limited, CQ ^ Slough, Bucks and 265, Strand, London, W.C.2. Showrooms : 179, Strand, W.G.2. Advanced design and fine craftsmanship is obvious in every one of the McMichael 1937-38 models, and a unique all-wave experience of over 11 years guarantees exceptional efficiency. The traditional McMichael reliability is allied to cabinet work of unusually fine construction at prices to suit all pockets. Models on view arc as follows :— / MODEL 371.—This inexpensive all-wave superhet places an efficient performance within reach of all \ the band-pass 7-stage chassis is sensitive and selective and the tone really good. Polychrome flying tuning shows light-pointers and luminous station names. 10^ Gns. for A.C. mains. A.C./D.C. 11 Gns. MODEL 372.—The extra tonal quality of the McMichael twin-stereophonic speakers is here offered with an efficient all-wave performance for a very moderate cost. The 6-valve 8-stage chassis has Polychrome Flying Tuning, Magic Eye and Tone Control; the inlaid walnut cabinet is i piano-finished. 14* Gns. for A.C. mains. MODEL 373.—The ideal set for the listener who requires an absolutely self-contained all-wave battery transportable with no external connec- ^ tions, in a handsome walnut cabinet. Even on short wavelengths, the ; performance is comparable with that of an aerial model and the 9-stagc ^ chassis is very economical in current consumption. 14 Gns. with batteries. MODEL 374.—A most convenient and efficient all-wave transportable for the flat dweller with A.C. electricity supply ; it needs only a mains connection for full efficiency and a world-wide choice of programmes. The powerful 6-valve 8-stagc chassis has Polychrome Tuning and Magic Eye Indicator. 16 Gns. for A.C. mains. MODEL 401.—Really exceptional value in consoles—a powerful 7-stage all-wave circuit, plus a really fine piece of furniture at little more than the cost of a table model. You could hardly wish for greater range, ! / il'J. better tone or a more solid and well finished cabinet. 14 Gns. for A.C. >;■< mains. MODEL 375.—This must surely be the radiogramophone de-luxe, with j unusual beauty, power and simplicity. The cabinet is of selected grained walnut with a particularly powerful 6-valvc 9-stage all-wave chassis supplying 6 watts to twin stereophonic speakers. A reliable 8-record automatic changer is available. 29 Gns. for A.C. mains (with Auto-changer, 35 Gns.). ! MODEL 137.—A luxury All-wave radio in every sense of the word. The ' bow-fronted walnut cabinet is delightful and the self-tilting giant dial rises automatically to face you as the lid is opened. Fitted with twin stereophonic speakers and Magic Eye. 16£ Gns. for A.C. mains (A.C./ D.C. 17 Gns.). Stand 42s. extra. MODEL 135.—This is the set for the critical listener who does not, however, require short waves. The period cabinet of inlaid walnut, Giant Dial Tuning and twin stereophonic speakers combine in a flawless i- performance. 15 Gns. for A.C. or A.C./D.C. mains. Stand 42s. extra. MODEL 378.—Designed for the country listener with outside aerial facilities, offering all-electric performance from an all-wave battery circuit. Powerful 5-valve 7-stage all-wave chassis, large moving coil speaker and inlaid walnut cabinet; tone control, local-distance selector, etc. 12i Gns. with batteries. MODEL 367.—Every home can make use of a portable as efficient as this one. McMichael 367, although light and compact, has range enough to bring in many programmes, tone really worth listening to, and negli­ gible running costs. In blue or maroon rexine. 8* Gns. with batteries. MODEL S.M.C.—In appearance and performance this is a real piece of workmanship. The hide case contains a superbly finished chassis with unusual range and volume. Under most arduous conditions this model has many times proved itself the world’s leading portable. 15 Gns. with batteries. ■ MODEL 362.—An A.C. superhet designed for short-wave listening as easy, reliable and enjoyable as the finest technical skill can make it. Tonal quality is very good indeed, sensitivity high and a special band spread pointer enables any station to be logged for future reception. 15* Gns. for A.C. mains. . J . , r MODEL 366—A most original and practical instrument, designed tor the listener with little space available. The Giant Dial for tuning is mounted inside the lid, vertically in front of the user’s eyes ; for broad­ cast wavelengths only. 24 Gns. for A.C. mains. 69 . *

“ Members of our Technical Staff will be in attendance at Olympia during the course of the Show. Appointments can be arranged by telephone ... Temple Bar 9738.”

FITZWILLI AM WORKS . SHEFFIELD Telephone: 41341 Telegraphic: Darwins, Sheffield

BIRMINGHAM : LONDON: 49/51 CORNWALL ST.. 3. BRETTENHAM HOUSE. TcL: CEN. 1531. LANCASTER PLACE. W.C.2. Tel.: TEMPLE BAR 9738. FRANCE: GERMANY: BELGIUM: Darwins Limiltd, Darwins Limited, Acieries Darwins S.A. R. H. Aquarius, Ritterstrasse 89, 35 Rue de I'Orienl, 246 Bourse de Commerce, Berlin, Brussels. Paris. S.42. U.S.A.: AUSTRALASIA: Darwin & Milner Inc., Amalgamated Wireless {Australasia), Ltd. 1258-1264 West Fourth St.. 47 York Street, Cleveland, OHIO. Sydney, N.S.W.

70 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Pye, Limited, Radio Works, Cambridge. 60 The range of 1937/8 Pye Receivers, Consoles, Radio-gramophones and Teleceivers is particularly comprehensive. It embraces external aerial models and portables, both for battery and electric mains operation and of the 2 waveband or multi­ channel type. From as low as £8 for the Q70 battery set the prices rise to the more expensive radiogramophones and Teleceivers. There are multi-channel sets with 3 or 5 wave­ bands (including television “ sound ”) and special models for overseas use. An innovation are the multi-channel portables, offering world-wide reception without any external connection whatsoever. Universal (A.C./D.C.) mains receivers are available as portables or for use with an external aerial. The cabinet work of new and graceful design will delight the eye and has been conceived to tone with modern or period home­ furnishing schemes. The Pye Teleceivers incorporating the very latest technical advances give a clear and flickerless black and white picture. All receivers, irrespective of their price, give 93 per cent, natural tone rendered possible by constant technical research work by Pye engineers. Briefly, there is a specification to suit every purchaser at a price to suit every pocket. MAKE A POINT OF INSPECTING THE FOLLOWING RECEIVERS :— Q.AC5.—5 Waveband (including television “ sound ”) A.C. mains superhet. Q.AC2.—A.C. Mains superhet priced at only 8 guineas. Q.AC3.—3 Waveband A.C. Mains superhet with many novel features. Q.PB—QP.AC 3 WAVEBAND PORTABLES for batteries and A.C. mains. Q.SP—Q.SM Straight circuit portables at £11 and 10 guineas respectively. “ Baby ” Q—“ Baby 55 Q.U. Midget portables for batteries and universal (A.C./D.C.) mains. Q.U.3—Q.B3.—3 Waveband receivers for Universal (A.C./D.C.) mains and battery operation. Q.S. Loud Speaker and Remote Control. Radiogramophones. Consoles. Teleceivers. NOTE THE FOLLOWING SPECIAL FEATURES : Multi-range tuning dial, planetary selector unit and flywheel tuning control on the Q.AC5. Illuminated “ Line-light ” station indicator and “ Electric ” “ Eye ” tuning indicator on the Q.AC3. Extreme portability of the “ Baby ” Q. Graceful cabinet design of all models. Symmetrical chassis layout. Reverse feedback in the Q.PB. Band-pass circuit in the Q.70. Clear black and white picture of the Teleceivers. 71 N G_S -Tk i / OF THE \

To the Cossor organisation—the largest of its kind in the British Empire—belongs the credit for many impor­ tant developments in Radio, Television and their associated i fields. Continuous research and experiment ensures that i Cossor products are always the most efficient and most i up to date of their type. No avenue of research is ignored in the search for increased efficiency and dependability.

A. G. G08S0R LTD. Manufacturers of VALVES RECEIVERS AND RADIOGRAMS TELEVISION • CATHODE RAY TUBES • NEON I SIGNS LAMPS • SCIENTIFIC MEASURING EQUIPMENT j Full details of Cossor Products are obtainable on application to Head Office : COSSOR HOUSE, HIGHBURY GROVE, I LONDON, N.5. Telephone: Canonbury 1234 (30 lines). ! Telegrams: Amplifiers, Phone, London.

Works: Distributing and Service Depots at: Cossor Works, Highbury Grove, N.5. BIRMINGHAM : - M/16, Carrs Lane (4) Cossor Valves. BRISTOL . - M, Bath Street (I) Aberdeen Works, Aberdeen Lane, N.5. CARDIFF - « . - 4. Park Lane DUNDEE - - 34, Dock Street Electric Lamps and Stgr*. GLASGOW . 21, Waterloo Street (C.2) Kelvin Works, Kelvin Road, N.5. LEEDS - - Murray's Bldg., Cossor Radio Receivers. Neville Street (1) Melody Engineering Works, N.5. LIVERPOOL . - 42. Paradise Street (I) Chassis and Metal Parts. MANCHESTER 6. 8 &• 10, Cannon Street (3) NEWCASTLE - - 3. St. Nicholas No. 5 Works, Highbury Grove, N.5. Buildings (I) Components and Receivers. NOTTINGHAM •> Mills Buildings. Cabinet Works, Leyton, E.10. Plumptre Place Cabinets and Woodwork. PLYMOUTH - - . I, Millbay Road Spencer Works, N.5. BELFAST - . ✓ 47. Queen Street Television Receivers. DUBLIN . . 185, Pearse Street

STANDS 61 & 163 i — OS 2382I 72 Stand No. Grand Hatx, Ground Floor. Stand No. Memoranda. A. C. Cossor Ltd., 61 Cossor House, Highbury Grove, London, N.5. 61 The Cossor Exhibit on Stand No. 61 presents a most interesting and com­ prehensive range of Radio Receivers, Television Receivers, Radiograms, Valves and other products. TELEVISION RECEIVERS.—Cossor Television Receivers giving a clear black and white, rock steady picture of full visual and aural enter­ tainment value, and embodying the latest technical' developments are shown in complete and chassis form. SERIES “ 38 ” “ MELODY MAKER ” RECEIVERS are displayed and comprise three models with several outstanding features. The two All-Wave models arc each equipped with a specially developed dual circuit that is as practical as it is ingenious. Medium and Long Wave stations arc received on a modern version of the Screened Circuit, but when switched over for Short Wave reception the circuit is automatically converted into an efficient Superhet. This arrangement gives a highly efficient performance on all three wave-bands. Each model has an 8-in. moving coil speaker, large tuning dial and simple controls. The three receivers in this series are as follows :— Model 238.—Battery Receiver with 3 Pentode Valves. Model 338.—ALL-WAVE 3-valve Battery Receiver with High Slope Output. Model 348.—ALL-WAVE 3-valve A.C. Mains Receiver with Triode Power Output. ALL-WAVE SUPERHET RECEIVERS.—Complete series of Battery and Mains Operated Models with many new and exclusive developments are shown, including the following :— SERIES “ 48 ” ALL-WAVE SUPERHETS.—Four Table Models operat­ ing on Short, Medium and Long Wave Bands, each incorporating Permea­ bility-Balanced I.F. Transformer, Automatic increase of Selectivity and Sensitivity on distant stations, Full-floating Anti-microphonic sub­ chassis, 30-1 double reduction Slow-motion Tuning Drive, Special High “ Q ” Coils, Dual Intermediate Frequency Changing, Positive Switching and numerous other attractive features. The four table models comprise :— Model 483.—3-v. Battery Model with Special High Slope Output Valve. Model 484.—3-v. A.C. Mains Model with Special High Slope Output Valve. Model 484U.—3-v. D.C./A.C. Mains Model with Special High Slope Output Valve. Model 485.—4-v. Battery Model with Quiescent Push-Pull Output Valve. “ SERIES 58 ” ALL-WAVE SUPERHETS comprise three Table Models operating on Short, Medium and Long Wave Bands. As brilliant inter­ pretations of up-to-date superheterodyne principles several interesting and practical innovations are employed, notably Controlled Band-Width Tuning, which enables reception to be varied to obtain the best possible results under all conditions. Other features include Double Tuned Band-Pass Circuit on Medium and Long Waves, with High “ Q ” Coils. Single Pre-selector Circuit for Short Waves. Permeability-Balanced 2nd I.F. Transformer. Diode Detector with Full Delayed A.V.C. and Quiet Tuning. The Triple Flexible Mountings for Gang Condenser, Sub-chassis, and Main Chassis should be noted. Exact tuning is simplified by a large dial and new positive-action 30-1 slow-motion Drive. The A.C. Mains Model has the additional refinement of a Tuning Indicator Lamp, the light from which decreases in intensity as synchronism is approached. The Table Models comprise :— Model 583 for Battery Operation. Model 584 for A.C. Mains Operation. Model 584U for D.C./A.C. Mains Operation. CONSOLE RECEIVERS.—The Series “ 48 ” includes 3-band Superhet Console Models for A.C. Mains and D.C./A.C. Mains operation and embodying all the unique features of the Table Models described above. RADIOGRAMS.—The Series “58” includes two Console Radiogram Models with all the special features of the Series plus Silent Induction Motors and complete record-playing equipment. Models for A.C. Mains and D.C./A.C. Mains are shown. VALVES.—Cossor Valves for every purpose are exhibited including 2-volt Battery Types, Indirectly Heated Mains Valves of the 4 v. 1 amp., 16 v. .25 amp. and .2 amp. series and Rectifying Valves. Amongst the various types shown are the Screened Pentagrids, High Slope Output Pentodes, Output Tetrodes, Triode Hexodes, and Double Quiescent Output Pentodes. 73 PIONEER PAPER

IN RADIO

Since the earliest days of radio the EVENING CHRONICLE (Manchester) has led the way with special features, constructional competitions, technical services, etc.

The EVENING CHRONICLE sponsored the first Manchester Radio Exhibition in 1924. Since then the EVENING CHRONICLE has maintained an unequalled radio service, and to-day is outstanding as the most productive paper for the radio advertiser.

EVENING CHRONICLE

RADIO EXHIBITION

This year’s Exhibition will be held at the City Hall, Manchester, from September 14th to September 25th. During this period the EVENING CHRONICLE will publish special radio pages each day. Already there is a big demand for space in the columns of the ^PioneerRadio Paper.

Evening Chronicle Manchester: withy grove. LONDON : 200, GRAY’S INN ROAD. Telephone: BLAckfriars 1234. Telephone: Museum 9841. Telegrams: “Chronicle, Manchester.” Telegrams : “ Allinewspa, Holb, London.”

74 3 Stand No. Grand Hall, Ground Floor. Stand No. - Memoranda. 62 The General Electric Go., Ltd M 54 Magnet House, Kingsway, London, W.C.2. 54 SPECIAL FEATURES. CHROMOSCOPIC AND FLOODLIT DIALS.—An even intensity of light is projected through the dial glass, causing station names to stand out vividly against a black ground. I TUNERAY TUNING INDICATOR mounted on the tuning dial affords true one-glance silent tuning. ROTAVERNIER.—This feature forms an integral part of the tuning pointer and moves with it, effectively dividing the scale into hundreds of divisions : of inestimable value, par­ ticularly on short waves, ensuring absolute accuracy of logging and re-location. MICRO-TUNING POINTER.—Offers the same advantages ! as the Rotavernier in a modified form. AUTOMATIC TWO-SPEED TUNING.—On one knob, entirely free from backlash. PRESELECTOR H.F. STAGE giving improved selectivity and image suppression, fitted on all models at 13i guineas and over. BALANCED QUALITY CONTROL.—One control giving the advantages of independent low and high note controls. TOUCH-LIGHTING reduces L.T. consumption in battery receivers, the dial being illuminated only when tuning. PROGRAMME SUMMARY. A.C. TABLE MODELS. Two-band. BC.3840, A.C. 38*, £7 15s. Od. Three-band. BC.3850, All-Wave 5*, £10 10s. Od. BC.3860, All-Wave Super 6*, £14 14s. Od. BC.3890, All-Wave Quality 8 - , £18 7s. 6d. Four-band. BC.3760, All-Wave 6, £19 19s. Od. BC.3880, Fidelity All-Wave 8, £26 5s. Od. D.C./A.C. MODELS. Three-band. BC.3855, Universal All-Wave 5, £11 Os. 6d. BC.3865, Universal All-Wave Super 6, £15 15s. Od. A.C. TRANSPORTABLE MODEL. Two-band. BC.3754, A.C.Transportable 5*, £16 16s. Od. A.C. RADIOGRAMS. Three-band. BC.3868, All-Wave Super 6, £27 6s. Od. Four-band. BC.3888, Fidelity All-Wave 8 Automatic Record Changer, £46 4s. Od. BATTERY RECEIVERS. Two-band. BC.3836, Battery S.P.3, £6 15s. Od. (complete). Three-band. BC.3846, Battery All-Wave 4, £11 Os. 6d. (complete). * Low Voltage Models also available, 10s. 6d. extra. WHEREVER A G.E.C. SET IS SOLD, OVERSEAS OR AT HOME, IT CAN BE ADEQUATELY SERVICED. PUBLIC ADDRESS AND SOUND AMPLIFICATION. Selected for display from an extensive range of equipment is the MICROGRAM—a self-contained microphone-gramophone equipment, incorporating a 3-stage 14 watt amplifier and turntable for A.C. operation with hand microphone, micro­ phone holder and output leads ; faders for control and mixing are incorporated. RADIO DRY BATTERIES.—A reliable battery for every set. 75 % I > s <

$ $ ® il i* aa!? a a 1 500.000 SQ. FT. OF FLOOR SPACE I Comprising 3 self-contained Halls. Can be let I separately or as a whole K

THE MOST COMPLETE & UP-TO-DATE sx EXHIBITION BUILDINGS IN EUROPE I it, S I Official Contractors to the i NATIONAL RADIO EXHIBITION s *I 8 since 1927 $ i it 8 S EXHIBITION STANDS : DECORATIONS 5 STAND - FITTING : FURNITURE ELECTRICAL AND ENGINEERING I V Designs and Estimates FREE '

1 OUR DEPARTMENTS ARE ALWAYS PREPARED TO ADVISE AND ASSIST EXHIBITORS

All enquiries should be made to the General Manager,

OLYMPIA LIMITED KENSINGTON. LONDON. W.14

Telephone: SHEpherds Bush 1141 (connecting all Departments)

70 Stand No. Grand Hald, Ground Floor. Stand No. Memoranda.

Ultra Electric, Ltd., Ultra Works, Western Avenue, Acton, W.3. 63 The range on the Ultra Stand this year comprises in all thirteen ALL-WAVE Models and a cabinet Moving Coil Speaker in addition to the Television exhibits. Three television instruments are shown. The first is for the reception of television signals only, and employs fifteen valve circuit and a specially produced Ediswan all-magnetic cathode ray tube giving a directly viewed black and white picture 7^ in. X 6$ in. The next model uses the same television receiver and gives similar pictures, but also includes an all-wave receiver capable of giving world-wide broadcast reception. This instrument uses 19 valves. Finally, there is a de luxe receiver giving a picture 10 in. X 8 in., seen in a mirror fitted in the cabinet lid. The receiver incorporated is as described above, and the whole equipment is fitted in a fine inlaid walnut veneered cabinet. The All-wave receivers, consist of six All-Electric Table Models, two Battery Operated Table Models, an All-Electric Console Receiver, and four All-Electric Radiograms, one of which incorporates Automatic Record Changer Equipment. All models incorporate extension speaker sockets with internal speaker switch. MODEL 121.—All-Electric ALL-WAVE 4-valve 7-stage Superhet. Covers Short, Medium and Long Waves. Two-speed slow motion tuning, and Full Automatic Volume Control. Gramophone pick-up sockets. A.C. mains, 12$ Gns. MODEL 122.—Similar to above model for D.C./A.C. operation, 13 Gns. MODEL 115.—World-wide reception is assured with this ALL-WAVE All-Electric 4-valve 7-stage Superhet. Tuning covers Short, Medium and Long Waves. Epicyclic slow motion tuning control. Delayed Auto­ matic Volume Control. A.C. mains, 10$ Gns. MODEL 116.—Specification as above, for D.C./A.C. operation, 11$ Gns. MODEL 50.—A de luxe 5-valve 8-stage ALL-WAVE All-Electric receiver covering Short, Medium and Long. Pre-H.F. stage. Two-speed slow motion tuning. Full Automatic Volume Control. A.C., 13$ Gns. MODEL 49.—D.C./A.C. version of above model, 14$ Gns. MODEL 123.—This de luxe Battery All-Wave Superhet 4/5-valve (Twin Pentode Output) 7-stage receiver gives assured world-wide reception. Tuning covers Short, Medium, and Long Waves. Slow motion tuning control. Quiescent Push-Pull output is incorporated. Tone Control and Delayed A.V.C. 12 Gns. (including Batteries). MODEL 105.—A popular priced All-Wave Battery 4-valve 6-stage Superhet covering Short, Medium and Long Waves. Reduction geared tuning control. 8 Gns. (Batteries extra). MODEL 125.—All-Wave All-Electric 4-valve 7-stage Superhet Console Model. This receiver tunes Short, Medium and Long Waves. Slow motion tuning. Delayed A.V.C. Gramophone pick-up sockets. A.C., 14 Gns. MODEL 133.—All-Wave All-Electric 4-valve 7-stage Superhet Radiogram. All controls, tuning scale and complete gramophone equipment are fitted beneath the lid. Operates on Short, Medium and Long Waves. Delayed A.V.C. A.C. mains, 23 Gns. MODEL 134.—Similar to above for D.C./A.C., 25$ Gns. MODEL 140.—As Model 133, but fitted with Automatic Record Changer. A.C., 28 Gns. MODEL 150.—All-Electric All-Wave 4-valve 7-stage Superhet Radiogram. World-wide reception and excellent reproduction of records. 1 unes Short, Medium and Long Waves. Slow motion tuning. Delayed A.v.u. A.C., 20 Gns. H.P. TERMS AVAILABLE ON ALL THE ABOVE MODELS. MODEL 326.—The new Ultra Moving Coil Cabinet Speaker has a special transformer incorporated enabling it to be used and is especially recommended for all models in the UL1KA OF TROUBLE-FREE RADIO. Handsome Walnut cabinet. 32s. oa. 77 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

64 The Marconiphone Co., Ltd., 64 Radio House, 210/212, Tottenham Court Road, 53 London, W.l. 53 Telephone : Museum 4144 (11 lines). Telegrams : Marconifon, Telex, London. ALL-WAVE RADIO, RADIOGRAMOPHONES AND TELEVISION. With a range comprising over twenty models there is a Marconiphone Receiver or Radiogram for every purse and purpose. Screen-grid and superhet battery receivers, all-wave superhet table grands for A.C. and D.C. mains, all-wave A.C. and D.C. superhet radiograms, and luxurious auto-radiograms—all designed to fill a definite need and all built to conform with the high standards established as a result of over 50 years’ radio research and experience. In this necessarily limited survey of the Marconiphone Stands it is not possible fully to describe the merits of the various models included in the 1937/8 range nor will space permit of an individual reference to every instrument exhibited. The following brief descriptions of certain of the models on view are intended merely as a guide to the general trend of Marconiphone progress. Attention is specially directed to the fact that world-wide reception is provided by practically every receiver and radiogram in the range exhibited, yet despite this almost universal provision of all-wave facilities, ease of handling and perfected musical reproduction still remain the predominant features of Marconiphone design. MARCONIPHONE TELEVISION RECEIVERS. Several Television models are exhibited on Stand No. 53 including Model 701 which combines Television and all-wave reception, Model 702 which is intended for the sound and vision reception of Television, and Model 703—the very last word in modern home entertainment providing Television, world radio and auto-gram in one instrument. MARCONIPHONE BATTERY RECEIVERS. MODEL 222.—An all-wave 4-valve battery superhet covering from 18— 2,000 metres in three wave-bands. Station named and wavelength calibrated dial. Very low battery consumption. MODEL 314.—Three-valve screen-grid battery receiver for medium and long waves offering a wide choice of programmes and real economy in running costs. MODEL 562.—Six-valve battery superhet transportable for medium and long wave reception, entirely self-contained and extremely economical in use. MARCONIPHONE ALL-WAVE TABLE GRAND SUPERHETS. MODEL 382.—An all-wave 4-valve superhet table grand for A.C. and D.C. mains. Very simple to operate, and covering three wave-bands from 16—2,000 metres. MODEL 347.—A luxury 6-valve superhet table grand for A.C. mains providing the world’s programmes on five wave-bands from 7—2,250 metres. Electronic visual tuning indicator. MODEL 559.—De-luxe 6-valve superhet table grand for A.C. mains providing unlimited programme entertainment from all parts of the world on three wave-bands from 16.5—2,000 metres. MODEL 561.—Ten-valve de-luxe superhet table grand for A.C. mains with world-wide range. Five wave-bands, electronic visual tuning indicator and all the very latest technical developments. MARCONIPHONE RADIOGRAMS AND AUTO-RADIOGRAMS. MODEL 575.—An up-to-the-minute 6-valve, three wave-band superhet radiogram with visual tuning, ample output and perfected quality of reproduction. For A.C. mains. MODEL 576.—Incorporating the same chassis as Model 575 but with automatic record-changer mechanism. MODEL 367.—De-luxe 6-valve five wave-band (7—2,250 metres) superhet auto-radiogram for world-wide reception. MODEL 563.—A luxury 10-valve five wave-band superhet auto-radiogram in a magnificent cabinet of true period design. See also Stand 53. 78

f Stand No. Grand Hall; Ground Floor. Stand No. Memoranda. Kolster-Brandes Ltd., 65Cray Works, Sidcup, Kent. 65 The 1937/8 range of K.B. All-Feature Radio Receivers embraces a variety of models of the all-wave type specially developed to meet the demand for satisfactory world-wide reception. The complete range is very comprehensive and includes battery receivers and models for operation from A.C. or D.C. mains. Both “ straight ” and superhet types are represented and prices range from 8 guineas for an efficient 3-valve all-wave battery receiver to 16 guineas for a highly developed all-wave A.C. superhet incorporating every worth-while modern technical feature. This season K.B. have entered the television field and are exhibit­ ing the first of their televisors designed in accordance with the most up-to-date principles of vision and sound reception. Demonstrations of the K.B. televisor are being given in Television Demonstration Room No. 11, in the National Hall. Further particulars can be obtained from ^Stand 65. Outstanding technical features of K.B. All-Feature Radio are :— . K.B. “ ALPHADEX ” DIAL.—An ingenious tuning dial on which stations are arranged alphabetically in groups, providing for instant selection of any desired station. TWO-SPEED TUNING, is a feature of all receivers fitted with the “ Alphadex ” dial and makes it extremely easy to tune accurately to short-wave and other stations. CATHODE RAY VISUAL TUNING INDICATOR.—A valuable feature of the K.B.660 All-Wave Superhet giving a clear visual indication when accurate tuning is accomplished. K.B. VARIABLE SELECTIVITY.—Permits the effective selectivity to be adjusted to ensure reproduction of the best possible quality at all times consistent with satisfactory elimina­ tion of interference between stations. AUTOMATIC TONE COMPENSATION.—Maintains the same excellent quality of reproduction at all volume levels by compensating for the apparent losses of high and low notes when volume is reduced. DELAYED AUTOMATIC VOLUME CONTROL minimises fading and permits full power output to be obtained when receiving weak stations. MUTING.—This feature of the K.B.660 All-Wave Superhet provides at will a quiet background between stations. K.B. ALL-WAVE “ REJECTOSTAT ” ANTI-DISTURB­ ANCE AERIAL SYSTEM rejects disturbances caused by electric motors, traffic lights, lifts, signs, car ignition systems, etc. The “ Rejectostat ” All-Wave Aerial System is an exclusive K.B. feature and covers a total wave range of 13— 2,000 metres without switching, thus effectively rejecting disturbances on short, medium and long wavelengths. From one to one thousand receivers may take the same or different programmes from a single “ Rejectostat ” Aerial with freedom from electrical or mutual interference. OTHER K.B. FEATURES include band-pass input circuits, special input circuits in superhets to eliminate “ whistles,” the most modern types of valves, full-vision tuning dials, built-in mains filters to ensure silent “ background ” when die receiver is operated from noisyjmains, high fidelity moving coil speakers, etc. K.B. CABINETS incorporate elegant modern designs and are soundly constructed of specially selected materials by skilled craftsmen in the K.B. factory. 79 By Appointment Three Magic Words. • •

"HIS MASTER S VOICE”

HEY stand for all that is best in Radio, just as they have stood for Supremacy in Records ever since records Twere made.

EMPIRE’S LARGEST RADIO FACTORIES To-day, the great “His Master’s Voice” Factories at Hayes make annually more radio receivers and radiogramophones than any other factories in the Empire. Each instrument is backed by 39 years’ ce sound ” experience.

You can be proud to say,

45 H.M.V.” COSTS NO MORE All the same, the pride of possessing an “H.M.V.” Radio or Radiogram will cost you no more: they can be purchased at the rate of a few shillings a week. So why be content with ordinary radio? See your local “H.M.V.” Dealer about it; he is one of a few, specially selected to give you good service.

Symbol of Supremacy in RADIO RADIOGRAMS — T E L E V I S I O N

STAND NOS., Radio 66. Television 76

“His Master’s Voice,” 98/108, Clerkcnwell Road, London, E.C. 1, and Hayes, Middlesex. 80 Stand No. Grand Hall, Ground Floor Stand No. Memoranda.

66 “His Master’s Voice.” 66 76 98-108, Clerkenwell Road, London, E.G.l. 76 The following models are among the radio and television instru­ ments shown on the “ His Master’s Voice ” stands. “ HIS MASTER’S VOICE ” INEXPENSIVE A.C. MAINS INSTRUMENTS. “ His Master’s Voice ” Model 494 and 495 all-world receiver and radiogram, having similar 6-valve superhet chassis with automatic volume control, are priced at \2b guineas and 23 guineas respectively. This chassis incorporates an H.F. stage before the frequency changer, ensuring an exceptionally sensitive performance on all wave bands. Slightly more expensive instruments incorporating similar chassis, but having “ His Master’s Voice ” fluid-light visual tuning device, are Models 499 receiver and 490 autoradiogram, priced at 14£ and 34 guineas respectively. The latter incorporates the “ H.M.V.” 8-record automatic changer. An alternative model to the 495 radiogram is Model 492, having a horizontal cabinet instead of the upright type. The chassis of the latter instru­ ment is slightly different to the one incorporated in the other four models. The price of Model 492 is 22 guineas. These five instruments have wavelength ranges of 16.5—52, 195— 580, and 725—2,000 metres. A 7-valve A.C. receiver, Model 482, is slightly more expensive than Model 499 and is priced at 16 guineas. This instrument incorporates all the features of Model 499, but in addition, has an extra valve and possesses a Vernier scale, enabling a precise note to be made of the readings for short-wave stations. “ HIS MASTER’S VOICE ” A.C./D.C. INSTRUMENTS. A series of “ His Master’s Voice ” instruments to operate off A.C. or D.C. mains of 200 volts or more, incorporate similar 5-valve superhet chassis. This is of the all-world type, having wavelength ranges of 16.5—50, 200—580, and 750— 2,000 metres. The chassis is shown as a receiver as Model 486 priced at 13£ guineas. It is exhibited as a radiogram as Model 487 at 25 guineas, and is available in a similar cabinet but incorporating an automatic record changer as Model 493, at 33 guineas. It is interesting to note that this series of A.C./D.C. instruments operate off voltages between 200 and 250 without any adjustment. “HIS MASTER’S VOICE” 5 WAVE-BAND INSTRU- MENTS. A series of five “ His Master’s Voice ” instruments incorporating a 6-valve 5 wave-band superhet chassis are exhibited. Model 496 receiver priced at 19 guineas, Model 488 radiogram at 29£ guineas, Model 485a autoradiogram at 35 guineas, Model 498 autoradiogram at 40 guineas, and Model 582 “ Bureau ” autoradiogram at 50 guineas. Models 496, 498 and 582 have the “ His Master’s Voice ” fluid-light visual tuning indicator. The wavelength ranges covered by the 5 wave-bands of the chassis incorporated in these instruments are as follows :—7—16, 16.7—53, 46—141, 185— 560, and 750—2,250 metres. It will be appreciated that the first wave-band covers the television sound transmissions. An interesting feature of this range of models is the separate bass and treble tone controls, which assist in obtaining the best reception of the programmes received from all parts of the (Continued on next page.) 81 D Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

“His Master’s Voice.” 98-108, Clerkenwell Road, London, E.G.l. 66 (Continued from page SI.) world by these powerful instruments. The tuning scale arrangements incorporate a Vernier pointer which enables, the reception point for short-wave stations to be accurately noted. Model 582 is a combination of an autoradiogram and a walnut writing bureau, having cupboards for the storage of record albums which are presented with the instrument and accommo­ dation for notepaper. A combined blotter, map of the world and short-wave guide form part of the equipment. This instrument has a larger speaker than is fitted to the other models in this range. "HIS MASTER’S VOICE” 4 WAVE-BAND INSTRU­ MENTS. Two instruments, a radio receiver Model 469, at 19 guineas, and a radiogram Model 479 at 33 guineas, have similar four waveband superhet chassis. Features common to both models include variable selectivity, fluid-light visual tuning indicator, separate bass and treble tone controls, two-speed tuning and elliptical speaker. It covers the four wave ranges 11—35, 35—100, 195—580 and 725—2,000. “ HIS MASTER’S VOICE ” 10-VALVE INSTRUMENTS. The listener who requires a radio instrument giving the finest possible performance will be interested in the range of " His Master’s Voice ” 10-valve models. These comprise Model 650 receiver priced at 24 guineas, Model 655 “ Armchair ” receiver at 36 guineas, and Model 660 autoradiogram at 62 guineas. The chassis incorporated in these models gives an exceptionally powerful performance covering 5 wave-bands, and has variable selectivity. The ranges of the wave­ bands are 4.85—12, 11.3—34, 34—107, 195—580 and 725— 2,000 metres. The power output of this chassis is 10 watts, delivered by a high-fidelity push-pull stage. Important features of the tuning scale incorporated in this chassis are the " His Master’s Voice ” fluid-light visual tuning indicator, Vernier scale, and names of the stations including the principal short-wave ones. A special built-in aerial transformer is coupled direct to the main wave-change switch, so that the “ His Master’s Voice ” all-wave anti-static aerial which is particularly suitable for working with this instrument is auto­ matically adjusted to the wave-band which is being employed. Model 655 “ Armchair ” receiver is worthy of special attention. It incorporates a bookcase and has a flat top, covered with glass to provide a table of convenient height. It may be placed in the conventional position against a wall. It has two loudspeakers. Model 660 all-world autoradiogram has the standard “ His Master’s Voice ” 8-record automatic record changer. “HIS MASTER’S VOICE” HIGH FIDELITY AUTO­ RADIOGRAM. “ His Master’s Voice ” Model 801 High Fidelity Autoradiogram has 10 valves and cupboards for record storage. Five luxuri­ ously bound record albums are presented with the instrument. Among the many interesting features of this model are the five wave ranges covering 7—16, 16.7—53, 46—141, 185—560 and 750—2,200 metres. It also incorporates the fluid-light visual tuning device, separate bass and treble tone controls, (Continued on next page.) 82 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. “His Master’s Voice.” 66 98-108, Clerkenwell Road, London, E.C.l. 66 (Continued, from page 82.) Vernier scale, three loudspeakers and has 10 watts undistorted output. The pick-up fitted to the 8-record automatic changer is of high fidelity type and is counterweighted. A short­ wave guide and electric clock are included on the main control panel. This luxurious instrument costs 80 guineas. GENERAL FEATURES OF “HIS MASTER’S VOICE” ALL-WORLD INSTRUMENTS. The above “ His Master’s Voice ” receivers and radiograms are of the all-world type, and enable programmes to be received from all parts of the world. These instruments have wavelength scales showing the names of the principal medium and long-wave stations, with special markings for the wave­ bands on which the principal short-wave stations are received. The wavelength scales of Models 660,655,650,469 and 479 also bear the names of the principal short-wave stations. They incorporate two-speed tuning knobs, and certain instruments, namely, Models 650, 655, 660, 469, 479, 496, 498, 490, and 499, have the new “ H.M.V.” “easy-grip ” control. Models 650, 655, 660, 469, 479, 494, 495, 499, 490 operate from 195—255 volts A.C. Model 482 operates from 95—260 volts A.C. The remainder, except battery instruments, operate from 200—250 volts. Models 486, 487 and493 operate from A.C. or D.C. of 200—250 volts. The A.C. receivers operate from 50—100 cycles and the radiograms from 50—60 cycles. The A.C./D.C. instruments operate from 25—60 cycles. All mains models have tone controls and Models 801, 650, 655, 660, 469, 479, 496, 582, 488, 498 and 485a have separate bass and treble tone controls. The speakers are of the moving-coil type, and the cabinets are finished in walnut and are made by “ His Master’s Voice ” in their factories at Hayes. “ HIS MASTER’S VOICE ” BATTERY RECEIVERS. Four “ His Master’s Voice ” battery receivers have different chassis covering the requirements of all listeners not possessing electricity supply. Model 464 is a de luxe battery transportable receiver, priced at 15i guineas. It is completely self- contained and incorporates a built-in frame aerial, a six- valve chassis with automatic volume control, moving coil speaker, ball-bearing turntable and covers wavelength ranges of 200—550 and 900—2,000 metres. An interesting feature of this model is the battery arrangement, the high-tension bat­ tery being divided into two sections. The chassis incorporates an automatic bias device which ensures the best quality of reproduction throughout the life of the battery. Model 166 priced at 13 guineas is an all-world superhet battery re­ ceiver, having 5 valves and automatic volume control It covers three wave ranges of 18—50, 195—580 and 840—2,000 metres. Model 149 is a 3-valve all-world battery receiver covering wave ranges of 18—50,195—560,785—2,000 metres, and is listed at 9i guineas. “ His Master’s Voice ” Model 167 battery receiver has 3 valves and covers wavelength ranges of 170—580 and 800—2,000 metres and costs 7i guineas. GENERAL DETAILS OF “HIS MASTER’S VOICE” BATTERY RECEIVERS. All “ His Master’s Voice ” Battery receivers have been designed with a view to obtaining economical current consumption. Models 166 and 149 incorporate two-speed tuning knobs and (Continued on page S5). 83 D2

Stand No. Grand Hale, Ground Floor. Stand No. Memoranda. “His Master’s Voice.” 66 98-108, Clcrkemvell Road, London, E.G.l. 66 (Continued from page S3.) Models 166 and 464 have three-position tone controls. All loudspeakers are of the permanent magnet moving-coil type, and the cabinets of the “ H.M.V.” battery receivers are finished in walnut. “ HIS MASTER’S VOICE” RADIO ACCESSORIES. Among “ His Master’s Voice ” radio accessories is the new “ H.M.V.” all-wave anti-static aerial providing static- free reception on wave-bands between 7 and 2,000 metres. It comprises three lengths of copper wire, aerial and receiver transformers, insulators and screened lead-in cable. It is priced at 45s. “ His Master’s Voice ” Pick-up Unit Model 11 costing 32s. 6d., includes a pick-up which may be fitted to practically any type of gramophone tone-arm, remote volume control and screened connecting leads, thus enabling a receiver to be converted into a radiogram. Models 184 and 172 Permanent Magnet Moving Coil Loudspeakers are particularly suitable for connection to “ His Master’s Voice ” receivers or radiograms. They are priced at £5 17s. 6d. and 3 guineas respectively, and incorpor­ ate volume controls which operate independently of the parent instrument. “ His Master’s Voice ” Record Filing Cabinet Model 10, finished in walnut, provides accommodation for 12 in. albums, or up to 400 10 in. or 12 in. records, and costs 7 guineas. Owners of radiograms will be interested in “ His Master’s Voice ” needles which ensure the best possible repro­ duction of all types of records. “ HIS MASTER’S VOICE ” TELEVISION RECEIVERS. On the “ His Master’s Voice ” Television Stand “ H.M.V.” Television Receivers are displayed. These models have been made by the engineers responsible for the successful television transmission system installed by the B.B.C. at the Alexandra Palace station, and have been specifically designed to operate off the high definition standard of transmission now used. All the instruments give the same size of picture, approximately 10 ins. by 8 ins. The pictures are exceptionally clear, brilliant and steady. Model 901 is a receiver for television sight and sound transmissions only, priced at 60 guineas. Model 900 is a combined television sight and sound, and 6-valve 5 wave-band all-world radio receiver, costing 80 guineas, and Model 902 combined television sight and sound, 6-valve 5 wave-band all-world radio and 8-record automatic changing electrical gramophone and is listed at 120 guineas. The prices of “ His Master’s Voice ” television receivers include the special “ H.M.V.” television aerial, free installation and maintenance for one year. GENERAL EXHIBITS ON “HIS MASTER’S VOICE” TELEVISION STAND. A number of general exhibits on the “ H.M.V.” Television Stand include an Emitron Camera, such as is used by the B.B.C. at the Alexandra Palace for the transmission of television pro­ grammes. The Emitron Camera has been designed and developed in the E.M.I. Research Laboratories at “ His Master’s Voice ” factories at Hayes, Middlesex. A model of these laboratories, including the transmitting aerials upon which the design of aerials at the Alexandra Palace was based, is also shown. Several other devices of special interest to television enthusiasts are also exhibited. 85 I

■V;

(Radio are

Stand 6? DmmstrdiM tit ROD (\ n • r • *1 m< Demonstration Room N°1

RADIO. RADIO-GRAMOPHONES AND TELEVISION

RADIO GRAMOPHONE DEVELOPMENT CO • » LTD • y GLOBE WORKS. NEWTOWN ROW. BIRMINGHAM 6. London — 40, Doughty Street, W.C.I. Manchester — 17, Bridge Street.

86 I Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. Radio Gramophone Development f/1 U' Company, Limited, Globe Works, New Town Row, Birmingham, 6. MODEL 516 TABLE RECEIVER. A 5-valve, 3-waveband All-Wave Superheterodyne Table Receiver, with Variable Selectivity, Mystic Ray Tuning, two-speed edge-lit glass dial, 8 in. Moving Coil Loud Speaker, output 3\ watts, fitted in Table Type Cabinet in Australian Walnut. A.C. Model, price 161 guineas ; Universal Model, 1^ guineas extra. MODEL 522 CONSOLE RECEIVER. A Console Receiver having the same specification as the 516, but mounted in a Console Cabinet of figured and straight-grained Walnut. A.C. Model, price 22 guineas ; Universal Model, 1] guineas extra. MODEL 535 RADIO GRAMOPHONE. A 5-valve 3-waveband All-Wave Superheterodyne Radio Gramophone, with Variable Selectivity, Mystic Ray Tuning, two-speed edge-lit glass dial, 8 in. Moving Coil Loud Speaker, output 3 watts, Automatic Record Changer, upright type Cabinet of figured and straight-grained Walnut. A.C. Model, price 35 guineas ; Universal Model, 38i guineas. MODEL 623 TABLE RECEIVER. A 6-valve 4-waveband All-Wave Superheterodyne Receiver, with Variable Selectivity, Mystic Ray Tuning, two-speed edge-lit glass dial with addi­ tional Logging Pointer, High and Low Tone Controls, Triode Output Valve, 8 in. Moving Coil Loud Speaker, undistorted output watts, fitted in Cabinet of figured and straight-grained Walnut. A.C. Model, price 25 guineas. Model also supplied for D.C. mains. MODEL 628 CONSOLE RECEIVER. A Receiver embodying a similar Chassis to the Model 623, but fitted in a Console Cabinet of figured and straight-grained Walnut. A.C. Model, price 28 guineas. Model also supplied for D.C. mains. MODEL 643 RADIO GRAMOPHONE. , A 6-valve 4-waveband All-Wave Superheterodyne Radio Gramophone, with Variable Selectivity, Mystic Ray Tuning, two-speed edge-lit glass dial, with Logging Pointer, 10 in. Moving Coil Loud Speaker, output 3 watts, Automatic Record Changer, fitted in Cabinet of figured and straight-grained Walnut. A.C. Model, price 45 guineas ; D.C. Model, price 47 guineas. MODEL 658 RADIO GRAMOPHONE. A 6-valve 4-waveband All-Wave Superheterodyne Radio Gramophone, . with Variable Selectivity, Mystic Ray Tuning, two-speed edge-lit glass dial, with Logging Pointer, Automatic Noise Suppression, Record Changer mixing 8 in., 10 in. or 12 in. records, fitted with Piezo Crystal Pick-up, 12 in. Moving Coil Loud Speaker, output 3\ watts, fitted in upright Cabinet of figured and straight-grained Walnut. A.C. Model, price 60 guineas. This Model supplied for A.C. mains only. MODEL 878 RADIO GRAMOPHONE. l An 8-valve 4-waveband All-Wave Superheterodyne Radio Gramophone, with Variable Selectivity, Mystic Ray Tuning, two-speed edge-lit glass dial, with Logging Pointer, Automatic Noise Suppression, Resistance- coupled Push-Pull Amplifier, 12 in. Moving Coil Loud Speaker, output 7 watts, Record Changer mixing 8 in., 10 in. or 12 in. Records, fitted in Cabinet of figured and burr Walnut. A.C. Model, price 80 guineas. This Model supplied for A.C. mains only. MODEL 1220 RADIO GRAMOPHONE. A 12-valve 4-waveband All-Wave Superheterodyne Radio Gramophone, embodying Variable Selectivity, Mystic Ray Tuning and two-speed edge- lit glass dial with additional Logging Pointer, Automatic Frequency Control, Automatic Noise Suppression, Resistance-coupled Push-Pull Amplifier with output of 12 watts and Contrast Control on Gramophone, Automatic Record Changer mixing 8 in., 10 in. or 12 in. records, with Piezo Crystal Pick-up, 12 in. Moving Coil Loud Speaker operated in special Pressure Sound Chamber. Fitted in Cabinet of figured and burr Walnut. Price for A.C. mains only, 120 guineas. EXTENSION SPEAKERS. A range of Extension Speakers is shown, covering all domestic require­ ments. R.G.D. ANTI-STATIC ALL-WAVE AERIAL EQUIPMENT. TELEVISION. R.G.D. Television Receivers and combined gramophone instruments. 87 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Philips Lamps Limited, Philips House, 145, Charing Cross Road, W.C.2. 68 Telephone : Gerrard 7777. Telegrams : Phillamps, Telex, London. The new Philips Receivers incorporate many important developments, some of which are summarised below. These improvements simplify the operation of the receivers and at the same time ensure results which represent a considerable advance upon the standards of reception pre­ viously obtainable. So much do these developments contribute to more enjoyable listening and ease of operation that Philips feel justified in summarising them in the phrase “ New Listening—You hear more, You do less.” Some of the features which create “New Listening ” include :— INVERSE BACK COUPLING—which gives much clearer reproduction and brings the treble and bass notes into their true perspective. Amplifier distortion is reduced and the available output is increased. TRIPLE DIODE CIRCUIT—This exclusive Philips development elimi­ nates “muzziness” and brings musical instruments into clearer “tone focus” than heretofore. STUDIO ACOUSTIC CABINET DESIGN—built into cabinets having the acoustically correct proportions and size, the new Philips receivers have a clear cut bass and middle register free from “ boom.” They are of striking appearance and exceptionally fine workmanship. CONTRAST AMPLIFICATION—restores much of the vital contrast between fortissimo and pianissimo unavoidably lost in transmission. NEW SOUND DIFFUSER—enables the listener to obtain faithful repro­ duction with the correct balance of high and low notes at the sides as well as in front of the loud speaker. NEW SELECTIVITY TONE CONTROL—A variable selectivity control combining Treble and Bass filters, which produces the best musical balance under both favourable and adverse conditions of reception. THE MONO KNOB—This unique system of control makes tuning still more simple—almost automatic. It enables the unskilled user to adjust correctly tuning, volume, tone and selectivity, simultaneously with one hand. D.C./A.C. CONVERTER—The new Philips Converter unit gives genuine A.C. operation on D.C. mains. Can be fitted in a few minutes to all Philips AX types receivers. Many other features, such as Adjustable Dials, Two-speed tuning, etc., all contribute towards more simple operation, better performance, and complete reliability. All the new Philips receivers are all-wave superheterodynes. The range consists of seven table models, one console, and three radio-gramophones and includes receivers for A.C., D.C., and battery operation. There is also an extension loud speaker and an exceptionally advanced television receiver. Models and prices are as follows :— TABLE MODELS. Type V7A, 7 guineas ; Type V7U, 1\ guineas ; Type 727A, 9* guineas ; Type 727U, 10 guineas; Type 785AX, 15 guineas ; Type 747A, 12£ guineas ; Type 747AX, 121 guineas; Type 787AX, 19i guineas; Type 714B, 14 guineas, including batteries ; Type 716B, 10 guineas, excluding batteries. CONSOLE MODEL. Type 701AX, 19£ guineas. RADIOGRAMS. Type 702A, 29 guineas; Type 702U, 31 guineas; Type 698A, 24 guineas; Type 698U, 26 guineas; Type 699A, 23 guineas, Type 699U, 25 guineas. EXTENSION LOUDSPEAKER. Type 2136, 57s. 6d. D.C./A.C. CONVERTER. Types 7860C and 7861C, 25s. TELEVISION. The new Philips Television receiver, Type TEL 6, marks an important step forward in television technique in that it makes use of a new projection system. The large Cathode ray tube hitherto necessary to obtain a picture 10 ins. wide has been replaced by a small tube which projects a brilliant picture on to a flat screen measuring 20 ins. by 16 ins. If a still larger picture is required, the built-in screen can be removed and the picture projected on a separate screen up to 3 ft. square. The instrument receives both the television picture and sound accompaniment. 88 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

E. K. Cole Ltd M 69 Ekco Works, Southend-on-Sea. 69 The EKCO range includes table models, a portable, consoles, a radiogram, power units and two television receivers. POINTS OF ESPECIAL INTEREST. “ Spin-wheel Tuning ”—a new method of tuning by a counter­ balance flywheel, giving smooth control and a high degree of accuracy. Built-in-Controls—instead of controls protruding as knobs from the face of the cabinet, they are recessed to show only the rims. Television “ Sound ”—all-wave models are designed to permit reception of the “ sound ” part of the television programmes. “ Mystic Eye ”—a novel and fascinating tuning indicator, opening and shutting to show when the set is accurately tuned. “ No H.T.” All-Wave Model—the first all-wave battery set to work without batteries, all power being supplied by ordinary L.T. accumulators. “ Pick-me-up ” Portable—a lightweight portable of small dimen­ sions ; weighing only 17 lbs. and working anywhere without aerial or earth. PRICES. DUAL-WAVE MODELS. AD38, A.C./D.C. mains, 8 guineas. B38, Batteries, £6 19s. 6d. (excluding batteries). PORTABLE. FI48, Batteries, £7 19s. 6d. (including batteries). ALL-WAVE MODELS. UAW78, A.C./D.C. mains, lOi guineas. BAW78, Batteries, 101- guineas (excluding batteries). BV78, “ No H.T.,” 13 guineas (including accumulators). AW88, A.C. mains, 12£- guineas. AW98, A.C. mains, 151- guineas. • BAW98, Batteries, 13 guineas (excluding batteries). CONSOLES. C78, A.C./D.C. mains, 141 guineas. C88, A.C. mains, 16 guineas. RADIOGRAM. RG109, A.C. mains, 241- guineas. POWER UNITS. AC10/20, H.T. supply, £2 2s. 6d. K10/20, H.T. supply and L.T. charging, £2 12s. 6d.

TELEVISION RECEIVERS—two models can be seen on stand or, in operation, in Demonstration Room. 89 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Bush Radio Limited, 70 Power Road, Chiswick, London, W.4. 70

A.C. SUPERHETS. TYPE S.W.41.—A 7-stage, all-wave superhet. Calibrated with station names. 10 guineas. TYPE S.W.43.—A 7-stage, all-wave superhet. with 7 tuned circuits and 8 WATT OUTPUT, and station name dial. 12 guineas. TYPE S.W.45.—A de luxe model of the S.W.43. A 6-valve superhet with 7 tuned circuits and 8 WATT OUTPUT. Special BUSH short-wave logging device, Magic Eye and Variable Selectivity. Station name dial. 15 guineas.

BATTERY SUPERHETS. TYPE S.B.44.—A 4-valve 6-stage superhet. with 7 tuned circuits and delayed A.V.C. Low current consumption. 8£ guineas (less batteries). TYPE B.A.43.—A 4-valve, 7-stage superhet. with 9 tuned circuits for Long, Medium and Short wavebands. H.T. consumption 10 m.a. 12 guineas (complete with batteries). TYPE B.P.5.—An entirely self-contained Battery Portable super- j het., with built-in frame aerials. A 5-valve, 8-stage receiver. H.T. consumption 9-9.5 m.a. 13 guineas (complete with batteries). I CONSOLES—(A.C. Models). TYPE S.U.G.43.—A 7-stage, all-wave superhet. with 7 tuned ! circuits and 8 WATT OUTPUT. 15J guineas. TYPE S.U.G.43G.—As S.U.G.43, but with large 12-in. Rola ! Speaker. 17J guineas. D.C./A.C. MODELS. TABLE MODEL TYPE D.A.C.43—A 4-valve, 7-stage all­ : wave superhet. with 9 tuned circuits. P.M. speaker. I2h guineas. : CONSOLE Type D.U.G.43.—A 4-valve 7-stage all-wave super­ het. with 9 tuned circuits and large P.M. speaker. 16 guineas.

RADIOGRAMS.—(A.C. Models). R.G.41.—A 7-stage, all-wave superhet. with large Moving Coil speaker. Electric Motor and automatic stop. 20 guineas. R.G.43.—A 7-stage all-wave superhet. with 7 tuned circuits and 8 WATT OUTPUT. Large 12-in. Rola M.C. speaker. Electric Motor and automatic stop. 26 guineas. R.G.43 Auto—As Model R.G.43, but with automatic record changer. 32 guineas.

RADIOGRAMS (D.C./A.C. Models). R.G.43 D.C./A.C.—A 4-valve 7-stage all-wave superhet. receiver with 9 tuned circuits and 12 in. Rola P.M. speaker. Electric Motor, etc. 29 guineas. R.G.43 D.C./A.C. Auto.—As above but fitted with automatic record changer. 35 guineas. 90 Stand No. rand alt round loor G H ., G F Stand No. Memoranda. Decca, 71 1-3, Brixton Road, London, S.W.9. 71 (Brunswick—Associated Company.) The DECCA and BRUNSWICK products exhibited upon this stand reveal the Company’s very natural desire—as manufac­ turers of DECCA, BRUNSWICK, REX, and other records— to feature record-playing instruments, most notable of which is the DECCA “ PORTROLA ”—their second model of England’s first Portable All Mains Radio-Gramophone. This and all other DECCA instruments, whether table receivers, table or floor type gramophones, are now of All-World All- Wave specification. All but one—and that a Battery Receiver at 7-i guineas—are superheterodynes. Of outstanding interest, and with several months’ actual user experience behind it, is the DECCA 55 Portable—unique with its large pictorial dial, only, on its front panel, speaker aper­ tures being at each side of the cabinet. Claimed to be the first Portable Receiver with a full 6-valve superheterodyne specifica­ tion to be sold in this country—made in this country—and weighing only 12\ lbs., it certainly is attractive at guineas, with its choice of three colour finishes and fold-flat carrying handle. Neat in design, with flush motor and control panel, and at what appears just the right size for the modern home or flat, is the model the maker’s term the DECCA 88—a five-valve super­ heterodyne A.C. Mains Radio-Gramophone at 18 guineas. A large three-wave band All - World All-Wave tuning dial simplifies station selection—the tone control operates on record reproduction as well as Radio. The pick-up is of DECCA design, to do full justice to modern electrical record­ ing. The cabinet is of real walnut hand polish finish. Among the Table Receivers, the Number 66 is of real interest: its chassis, characteristic of DECCA mechanical workman­ ship as a whole, is clean and straightforward. Again a large dial simplifies tuning ; a dynamic speaker—all DECCA models have dynamic moving coil types of varying sizes—ensures high quality reproduction. The DECCA 66 is the cheapest in the range at 9£ guineas ; and is, of course, of All-World All-Wave superheterodyne type for A.C. Mains. Cabinet of walnut and ebony. The DECCA range is completed by a Battery Model, No. 33, price guineas, and a de Luxe four-wave band A.C. Radio- Gramophone. For those who from time to time wish to supplement their radio listening by the use of a few records, DECCA offers the choice of hand wind or electrically driven Convert-to- Gram instruments, the use of which enables a receiver to reproduce records ; also there is the latest version of the DECCA portable gramophone. BRUNSWICK Receivers are also exhibited on this stand, and take the form of rather higher priced Portables, Table Models and Radio-Gramophones, designed and presented for those of us who wish to own highly individual instruments. The most expensive instrument is a ten-valve, five wave band— to include the television sound wave-lengths—record changer radio-gramophone, with an output of 12 watts. 91 Milliard Radio THE RADIO SET OF THE RADIO STARS

★ ★

Mullard radio receivers are owned and enthusiastically recommended by the world’s most famous radio stars, including : FLORENCE DESMOND EVELYN LAYE ELSIE RANDOLPH WEBSTER BOOTH BILLY COTTON FLOTSAM AND JETSAM FRED HARTLEY JACK HYLTON DEBROY SOMERS SYDNEY TORCH WESTERN BROTHERS Built by the makers of the famous Mullard Valves, these radio sets are constructed on a revolutionary new engineering principle, Mullard “Acoustic Design.”

Come and see for yourself STAND what this new ‘Acoustic Design’ is tike NO. -and why the Mullard has become the radio set of the radio stars! 72 I

92 tand o S N . Grand Hall, Ground Floor. Stand No. Memoranda.

77 The Milliard Wireless Service Co., Ltd., 72 " 225, Tottenham Court Road, W.l. ■ ~ The Mullard Wireless Service Co., Ltd., are exhibiting the full range of the well-known Mullard Master Receiving Valves, Transmitting Valves, Cathode-ray Tubes for television and laboratory work, and a range of radio receivers distinguished by the new Mullard engineering principle, “ Acoustic Design.” The following features all contribute to Acoustic Design, which means that cabinet and receiver are designed together to give pure, natural tone. The cabinet helps the loud speaker instead of hindering it. TRIPLE DIODE CIRCUIT, which increases the efficiency of the auto­ matic volume control, and at the same time prevents any possibility of distortion through its action. “ INVERSE FEED-BACK ” CIRCUIT, which eliminates harmonic distortion in the output stage. ACOUSTIC CABINET DESIGN, which cuts out undesired resonances and muffling. VARIABLE SELECTIVITY, whereby the bandwidth can be reduced when necessary, to cut out interference, or increased for finest tonal quality. COMPENSATED TONE CONTROL, whereby, when the high note response is decreased, the low note reproduction is automatically reduced in compensation, without the volume being affected. TONE DIFFUSER, a small plastic cone, inserted in the speaker, which eliminates “ beam-effect ” of high notes, so that all tones are heard as well at the side of the speaker as in the front. UNIT CONSTRUCTION enables acoustic design of moulded cabinets to be fully realised. Complete separation of circuits permits maximum efficiency without instability. Additional features are :— MULLARD “ MAGICONTROL.”—A genuine single-knob control, which is not only more convenient to use than several separate knobs, but also far more efficient. Tuning, volume, tone and selectivity are all controlled very simply with one hand, and tone balance is always technically correct. Everyone gets expert results. CATHODE-RAY TUNING INDICATOR.—Green rays on a fluorescent screen expand when you are dead in tune with your station, contract when you are the least bit “ off.” Tuning is made far more accurate than by ear alone. ALL-WAVE RECEPTION.—Besides the normal medium and long-wave ranges, the new Mullard receivers give world-wide reception on short waves. DUO-SPEED TUNING.—By simply reversing the direction of the tuning knob, you engage low gear for high-precision tuning. Especially valuable on the short waves. D.C. MAINS OPERATION.—Performance in every way equal to that of an A.C. mains receiver. An entirely new type of converter unit, fitted in a few moments without wiring alteration, converts the receiver for D.C. operation without any sacrifice of efficiency. MULLARD “ DISAPPEARING DIAL.”—A refinement by which the dial can be lowered out of sight when not in use, emphasising the appear­ ance of the set as a piece of fine furniture. The new 1937-38 range of Mullard receivers is as follows :— MULLARD M.B.3B.—A straight three-valve battery receiver, price ! 7 guineas. MULLARD M.B.S.3.—A four-valve all-wave battery receiver, price i 9 guineas. MULLARD M.A.S.2.—Five-valve all-wave mains receiver, price 7 guineas. MULLARD M.A.S.6.—Five-valve all-wave receiver, price guineas. _ MULLARD M.U.S.6.—Universal receiver for D.C. or A.C. mains, price i 10 guineas. MULLARD M.A.S.7.—All-wave receiver for A.C. or D.C. mains, price 12^ guineas. MULLARD M.A.S.8.—De luxe all-wave mains receiver, price 15 guineas. The Mullard Master Valves also exhibited include some new and ingenious types which have strongly influenced the design of many of the new season’s receivers. Of particular importance to those listeners who are not buying new receivers this year are the steps recommended to restore the original performance of their present sets. Visitors are cordially invited to bring their radio problems to the Stand. TRADE VISITORS are reminded that the new range of Mitcham Service Instruments are being demonstrated on the Mullard Stand No. 161. 93 I

mmmm

Each day ar Radiolympia thousands of Lissen owners make their way to Stand 73 to choose their new sets. For they have learned the difference between “Lissening” and just listening. They have learned to appreciate the true tone, the range, the perfect selectivity of Lissen Radios ; above all they have learned to appreciate their incomparable value for money. If you would like all the advantages of a luxury set at a price everyone can afford, visit Stand 73 to see and hear Lissen’s wonderful range of 7 dans free » new models. trial offer! Experience for yourself in your own home the wonders of “Lissening” before you buy your Lissen. Any of our representatives at Stand 73 will be happy to arrange for your local dealer to loan you a Lissen for 7 days free trial, 1ISSEN entirely without obligation to buy.

LISSEN LIMITED, ANGEL ROAD, EDMONTON, N.18. Telephone: Tottenham 3901

94 Stand No. i Grand Hall, Ground Floor. Stand No. Memoranda. Lissen Limited, 73 Angel Road, Edmonton, N.18. 73

As usual, the Lissen Display is of particular interest. It includes not only a complete range of Radio Receivers but also Dry Batteries, Components and Electric Torches.

Lissen have followed their firm policy of concentrating on incor­ porating in each set every really practical improvement that can possibly be included at the price. The specifications of this season’s models reveal some really unusual refinements even in the very low priced sets. This, combined with the impressive appearance of the cabinet designed, is proof enough that once again Lissen have fully succeeded in living up to their value-for-money reputation.

ALL-WAVE RECEIVERS. It is difficult to draw the attention to any one particular model in this range as they are all equally attractive, whether mains or battery operated. All these receivers incorporate superhetero­ dyne circuits and allow enjoyment of world-wide programmes at a very low cost to the user. Prices range from £8 17s. 6d. to £17 17s. Od.

BATTERY AND ALL-MAINS RECEIVERS. Make a point of seeing the handsome Lissen Model 8306. This is a 3-valve band-pass instrument giving a very wide range of programmes and possessing a high degree of selectivity. Output makes sure that all the volume you need is available, while the price, £5 12s. 6d., includes battery and accumulator. One of the finest examples of Lissen value-for-money.

All the battery sets shown have performances similar to their Mains counterparts. Do not forget to see the Transportable Models. There is a Mains Fidelity Output, a “ Class B ” Battery Set of modern design and the Lissen Picnic Portable. This Picnic Portable can be taken anywhere—on the beach, in the garden or wherever you may be going.

Lissen have always been interested in catering for the needs of the home constructor, and a very comprehensive display of Components is shown. —

A complete range of Lissen Torches is also on view together with refill batteries. The Lissen High Tension Batteries, as shown, comprise the universally known Standard, Super, Leader and Radio Ranges.

Needless to say, the attendants are entirely at your service and will be able to give you valuable help in recommending the most suitable receiver for your own district. They will be glad also to arrange a free 7-day trial of any Lissen model in your own home. Cordial invitations are issued to overseas visitors who will be particularly interested in the All-Wave receivers exhibited. 95 Dependable FERRANTI

RADIO for your sals'

THE LATEST AND FINEST

CAR RADIO UNIT 1 «e m ; m ON THE MARKET 2 GNS. mm w 6 Valves; long and medium wavj ranges; 1 5 rssi* S'TJrtMUt i station names on illuminated dial; \ Si moving coil speaker ; full A.V.C.; VJ tone control incorporating A Vo % ,/i bass compensation; jfc,. ,a“' 2k watts undistorted output. Rigs 8 3 NO PLUG SUPPRESSORS OVERHEAD OR UNDER-CHASSIS AERIAL DEMONSTRATION CAR AVAILABLE (ENQUIRE AT STAND 74)

STAND 74

FERRANTI TELEVISOR

Providing the most perfect radio and

television performance obtainable.

Direct viewing, giving clear and

contrasting pictures from a wide

angle of view-point. Magnificent

Walnut cabinet. Demonstration Room

No. 9 Television Section.

SEE THE TELEVISION EXHIBITION AT THE SCIENCE MUSEUM, SOUTH KENSINGTON

96 This set is gelling talked about * * .

in the Wireless World: “few superhets have given greater results”

in the Wireless Trader: cc will not suffer by comparison with many io or even 12 guinea models”

in the News Chronicle : “a Ferranti masterpiece”

in the Manchester Guardian :

Hardly surprising— •when you consider the price GNS and what you get for it.

An All-Wave Supcrhct for 9 gns. Think what Ferranti sets, as well as learning how to that means. World listening from near and far make the most of short-wave reception, on long, medium and short-wave bands. Paris, by reading our book " Round the World Budapest, Bombay, Schenectady .... waiting With Ferranti.” A free copy is yours for you at a turn of the dial. And your tuning for the asking at Stand Number 74 is made easier by the enlarged outer tuning scale of 180 degrees. Stand No. Ik Low running cost — the electricity consump­ tion is about equal to that of one 60 watt Other sets in Ferranti range lamp — helps to make a place for this set in f d 9 m All-wave superhet with Mag- every home. Ask your dealer to let you hear ^ nascopic Dial, in fine wood cabinet; full A.V.C. 12 gns. the Ferranti 837. You will be astonished that such a simple, and above all inexpensive, set 4 m w tm__ All-wave superhet, high fidelity ■ » 3 m model with Magnascopic Dial can give such splendid, undistorted and and full A.V.C. in fine wood cabinet. 17 gns. dependable reproduction on all wave bands. gTTV All-wave radiogram, the finest That s what Ferranti 837 gives you, so m value radiogram in'the show. no wonder it’s talked about. You can 23 gns. find out all about it and the other BATTERY MODELS FROM 6 GNS.

Fenanfi 837 FERRANTI RADIO METERS STAND 21

97 r i

* Sp

' ;. • •

98 .Stand No. Grand IT add, Ground Fr.ooR. Stand No. Memoranda.

Ferranti Ltd •1 74 Radio Works, Moston, Manchester 10. 74

On the FERRANTI Stand will be exhibited a complete range of All-Wave Receivers manufactured by this Company, as well as their latest Car Radio developments and Television Receivers. The actual models on view will be as follows :—

BATTERY MODELS. Types 637B. and 637BR.—Price 6 guineas and £6 10s. 6d. respectively.

Battery All-Wave Superhet Model 1137B, in Bakelite, price 11 guineas.

Battery All-Wave Superhet Model 1237B, in Walnut, price 121 guineas.

MAINS MODELS. The A.C. range will comprise the new FERRANTI 837 All- Wave model listed at only 9 guineas in bakelite, and the 1137 12 guinea model in walnut with macassar inlays and magnascopic dial, the latter device being an exclusive FERRANTI arrangement to facilitate short-wave tuning. It is also provided on the 1137B and 1237B battery models.

A 17 guinea model, the 1737, will be the highest priced FERRANTI table model on view, and incorporates nearly every modern refinement, being an all-wave set with a multi­ coloured dial, cathode ray tuning indicator, all-wave ranges, variable selectivity and high fidelity triode output.

An All-Wave Console, the 1937 A.C. model at 19 guineas, will also be shown, as well as an All-Wave Radiogram, the 2337, at 23 guineas.

CAR RADIO. The Car Radio exhibits comprise a section of a car dash-board and scuttle with the FERRANTI Car Radio installed in position.

TELEVISION RECEIVERS. Complete Television Receivers will be on view, as well as a Television Receiver Chassis, and FERRANTI Television Receivers will be demonstrated in the special Television . Demonstration Room. 99 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. 7S Whiteley Electrical Radio Co., Ltd., “7Z. Radio Works, Mansfield, Notts. ■ K High Fidelity ” reproduction apparatus in four different classes—Exten­ sion Loud Speakers, Chassis Loud Speakers, Domestic Broadcast Receiv­ ers, and Public Address Apparatus. EXTENSION LOUD SPEAKERS. Five Models are shown, together with the “ Long Arm ” Remote Control, which enables the receiver’s on/off switch to be actuated by a button on the extension speaker. STENTORIAN “ SENIOR ” (Type 38SC), consists of a large unit, cap­ able of carrying up to 5 watts, mounted in a walnut cabinet with con­ trasting veneers. The cabinet is acoustically balanced with the speaker’s output, and is lined with non-resonant material. Like other Stentorian I "Speakers, this instrument is easily matched to any type of receiver. A Volume Control is incorporated, and a push-button switch for actuating the “ Long Arm ” Remote Control, should it be desired to control the receiver from the extension point. Price, 63s. complete. STENTORIAN “ JUNIOR” (Type 38JC), is similar to the Senior model except that the speaker is of a more conventional size and the cabinet, although retaining the principle of acoustic balance and non-resonant lining, is of different appearance. Price, 49s. 6d. complete. STENTORIAN “ CADET ” (Type 38CC) is a moderately sized instru­ ment of similar appearance to the “ Junior ” model, and is similarly suitable for use with any receiver. Volume Control and push-button Switch are incorporated in the same manner. Price 39s. 6d. complete. STENTORIAN “ BABY ” (Type 38BC) incorporates the well-known “ Baby ” chassis in a slightly improved form, which is housed in a walnut veneered cabinet of simple design. It will work with any receiver. Price 29s. 6d. complete. STENTORIAN “OCCASIONAL” EXTENSION SPEAKER.—This is a new model consisting of a loud speaker contained in a small direc­ tional metal chassis and mounted on a metal floor stand with silent castors. A length of extension wire is mounted on a spring roller and housed in the base of the stand. When the loud speaker is required for I “occasional” use the speaker lead is simply connected to the receiver, and unwinds whilst the speaker is being taken to the room where it is to operate. When the volume control is at minimum and the speaker faced towards the listener the programme may be heard by one listener without disturbing the occupants of other rooms or neighbours. CHASSIS LOUD SPEAKERS. The complete range of Stentorian chassis, embodying a number of new features, is displayed. All have the new graduated moulded cone and new type of centring device, which allows increased sensitivity and greater reliability. All, with the exception of the “ Midget,” incorporate the “Microlode” matching device, giving accurate adjustment for any receiver or output valve. “ Senior,” “ Junior,” “ Baby ” and “ Midget ” models at 42s., 32s. 6d., 23s. 6d. and 17s. 6d. respectively. Also displayed is a new model known as the STENTORIAN “ ELLIPSIS,” for use with receivers where height of cabinet is restricted. This instru­ ment, whilst having resonances of extremely small amplitude, is not capable of carrying outputs in excess of 2\ watts. Chief prominence amongst the Chassis is given to a new type of speaker for use with high quality amplifiers. Less sensitive than the normal design, this instrument, nevertheless, has a far wider range and straighter characteristic than is obtainable by conventional methods. The curve between 40 and 14,000 cycles is level within 5 d.b. throughout. A wooden cabinet is an integral part of the instrument. This chassis is definitely unsuitable for use with ordinary broadcast apparatus, and is for use only with extremely high fidelity amplifiers or a receiver of a special type, of which details are provided with each instrument. RECEIVERS. A new range of Broadcast Receivers is shown. All are designed with special regard to quality of reproduction, and are fitted with speakers of larger dimensions than the conventional size. The range consists of a 5-valve (including rectifier) four-waveband superheterodyne ; 4-valve battery all-wave superheterodyne; 3-valve A.C. all-wave receiver ; 4-valve battery portable ; and 3-valve battery portable—the last two being supplied complete with self-contained frame aerial and batteries. The fourth class of goods consists of PUBLIC ADDRESS APPARATUS. A 25-watt A.C. Amplifier and an 8-watt A.C./D.C. Amplifier, with appropriate Microphones, Gramophone Turntables, Loud Speakers and Directional Flares, are on view. . w ... The display is completed by a range of Valveholders, Switches, Mouldings and Capstan Work. l 100 Stand No. Grand Hart., Ground Floor. Stand No. Memoranda.

76 “ His Master’s Voice.” 76 66 98-108, Clorkenwell Road, London, E.G.l.

For particulars of Exhibits, see Stand 66.

77 Westinghouse Brake 77 1 ' & Signal Co., Ltd., 1 /

82, York Road, King’s Cross, London, N.l.

A complete range of rectifier units suitable for use in radio and television receivers will be on view, including H.T., H and J types for high tension, “ L.T.” and “A” types for low tension and battery charging, “ Westectors ”—high frequency recti­ fiers for detection, automatic volume control, battery economy, etc.

The H.T. types this year have been revised, and a complete new range of uncased units is now offered for the first time for home construction use. These units provide outputs of the same values as those previously available.

For the trader there is a complete range of commercial battery chargers, single and multi-circuit type, of various outputs, as well as rectifier units suitable for change-over work.

: 70 The British Broadcasting Corporation, 70 ■ ^ Broadcasting House, Portland Place, W.l. " ^

Listeners can choose a week’s radio entertainment in advance from the details and illustrations of the complete B.B.C. programmes published in “ RADIO TIMES,” price 2d., every Friday.

“ WORLD RADIO,” also published on Friday, price 2d., contains foreign programmes of long, medium and short-wave stations throughout the world. \ __ n The talks which listeners have heard, or perhaps missed, are printed with exceptionally good illustrations in “ THE LISTENER,” price 3d., every Wednesday.

On this stand a comprehensive range of pamphlets published by the B.B.C. in connection with Broadcasts to Schools and Talks is available to visitors.

See also Stand 51 on the opposite side of the Main Stairway.

101 Stand No. Grand Halt., Ground Floor. Stand No. Memoranda.

TO British Belmont Radio, Ltd., 70 ■ ^ Belmont House, Ridgmoynt St., London, W.G.l. ■ The British Belmont Radio exhibit covers a comprehensive range of All-Wave Superhet. Receivers and Radiograms to suit every purse and requirement. Outside the range of All-Wave Superhet. receivers and radiograms, British Belmont are showing two compact models at £5 10s. Od. and £5 12s. 6d. which are presented in a variety of coloured cabinets made for the first time from a revolutionary composition (not bakelite) which provides acoustic qualities of amazing character. Prices of all-wave models range from the Table Model at 10 guineas to the Radiogram with automatic record change at 30 guineas. All superhet. All-Wave models provide the most up-to-date improvements and incorporate the Cathode Ray Magic Eye Visual Tuning, Constantly Variable Tone Control, Automatic Volume Control, Sockets for extension speakers, and Pick-up Switch. The dials are illuminated and are j calibrated in metres and station names and each wave-band is shown in different colours. Automatic Wave-Band Indicator is also incorporated in the dial. All valves are British made American Octal type and, with the exception of the compact receivers in composition cabinets, the cabinets are all of high : grade beautifully figured walnut. Brief details of the full range are as follows :— Compact Model No. 500, price £5 10s. Od. Compact Model No. 505, price £5 12s. 6d. Table Model No. 700.—7 valve All-Wave Superhet. Covers 15.5 to 2,100 metres for A.C. Mains, 200/260 volts. Price, 13 guineas. Table Model No. 800.—8-valve, All-Wave Superhet. Universal Receiver for A.C./D.C. Mains, 100 to 260 volts. Covers 15.5 to 2,100 metres. Price 13i guineas. Radiogram Model 720.—7-valve All-Wave Radiogram-De-Luxe for A.C. Mains, 200 to 260 volts. Covers 15.5 to 2,100 metres. Incorporates Garrard Silent Induction Motor with self­ stopping device. Price, 25 guineas. Size overall, 41 ins. high, 24 ins. wide and 16 ins. deep. Radiogram Model 721.—Similar in every detail to Radiogram Model 720 but incorporates automatic record changer. Price 30 guineas. The remaining two models are a 6-valve A.C./D.C. Model at 10 guineas and a 9-valve 4-Band All-Wave Model at 18 guineas. All Belmont Receivers are fully guaranteed for six months (valves three months), and they are all obtainable on very convenient Hire Purchase Terms.

on The New London Electron Works, OA ou Limited, East Ham, London, E.6. Electron 100 per cent. Copper Aerial. 100 ft., 3s.; 75 ft., 2s. 3d.; 50 ft., Is. 6d. j 25 ft., 9d.; 15 ft., 6d. Electron 100 per cent. Earth Wire.—6d. per box. Superial Aerial.—100 ft., 3s. 6d.; 75 ft. 2s. 6d.; 50 ft., Is. 9d.; 25 ft., Is. Screened Superial.—100 ft. Aerial in one continuous length, 20 ft. of which is screened with braided tinned copper, 5s. ; 75 ft. entirely screened, 7s. 6d. (Continued on next page.) 102 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. gQ The New London Electron Works, gQ \

East Ham, London, E.6. (

Q| Dubilier Condenser Co. (1925), Ltd., Cl ^ Ducon Works, Victoria Road, North Acton, W.3. A complete and comprehensive display of Condensers and Resistances for incorporation in radio receiving, transmitting and television apparatus. Also condensers of various types for industrial purposes, power factor correction, capacitor motors, electric furnaces and Radio Interference Suppressors. In addition to our already well-known components new designs in Metallised Mica Condensers, Resistances, Paper and Electro­ lytic Condensers will be of particular interest to designers and manufacturers.

Q2 The British G.W.Z. Battery Co., Ltd., QO v-'te/ Falmouth Road, Trading Estate, Slough, Bucks. C74* The programme of The British G.W.Z. Battery Co. of Slough, Bucks, for the 1937/8 season is featured by the addition of several new lines which make the G.W.Z. range one of the most comprehensive available in the battery world. In addition to all types of standard H.T. Batteries, G.W.Z. list a full range of Replacement Batteries covering practically every popular set on the market. The G.W.Z. exhibit includes the following sections :— (a) Standard H.T. and Grid Bias Batteries for Wireless. (b) Replacement Batteries for all Portable and Transportable Sets. (c) Refill Batteries for Pocket Lamps, Torches, Cycle Lamps, etc. (cf) Dry Cells, Leclanche Cells, Sack Elements. All lines are marketed at highly competitive prices which carry attractive discounts for the trade. At the same time and more strongly than ever before, G.W.Z. sell under the slogan “ Quality First,” which has its justifica­ tion, considering the fine facilities which they have available at their modem factory at Slough.

Britannia Batteries, Ltd., 83 Britannia works, Redditch, Worcs. 83 Pertrix High Tension Radio Dry Batteries. Pertrix “ Bulldog ” High Tension Radio Dry Batteries. Pertrix Special Replacement High Tensiori Radio Dry Batteries. Pertrix Grid Bias Dry Batteries. Pertrix Lighting Dry Batteries. Pertrix Low Tension Dry Batteries for Export. Pertrix Bulldog Lighting Dry Batteries. Pertrix Accumulators with Free-acid electrolyte (dry). Pertrix Accumulators with Jelly-acid electrolyte. 103 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. Pilot Radio, Ltd 84 87, Park Royal Road, North Acton, London, N.YV.10. TYPE BL-550.—5 valve (including rectifier) superhet. for A.C. | mains. Medium and long waves only. 190-2,150 metres. Moving coil speaker. Walnut cabinet. Price 8£ guineas. TYPE B-344.—4 valve all-wave superhet. for battery operation. Three wave bands, 16-2,200 metres. Q.P.P. output. Moving coil loud speaker. Massive walnut cabinet with battery space. Price 11J guineas. TYPE U-535.—5 valve (including rectifier) all-wave superhet. for A.C. mains, having three wave ranges, 16-2,200 metres. Moving coil loud speaker. Walnut cabinet. 12J gns. TYPE U-225.—6 valve (including rectifier) all-wave superhet. for use on A.C. or D.C. mains (Universal). Three wave ranges, 16-2,140 metres. Moving coil loud speaker. Walnut cabinet. Price 14 guineas. TYPE 375.—6 valve (including rectifier) Universal superhet receiver. All-wave. Wave range, 16-2,140 metres. 14igns. TYPE U-385.—8 valve (including rectifier and tuning beacon) all-wave superhet. for A.C. mains. Three wave ranges, I 16-2,200 metres. 6 watts output. High fidelity moving coil loud speaker. Massive walnut cabinet. Price, 15 guineas. TYPE U-650.—7 valve (including rectifier and tuning beacon) i all-wave superhet. for A.C. mains. Four wave ranges, 16- 2,100 metres. Moving coil speaker. Walnut cabinet. 16 gns. TYPE U-690.—As above but for D.C. mains only. 17 gns. TYPE 475.—7 valve (including rectifier and tuning beacon) superhet. for use on A.C. mains. Having four wave bands, 16-2,100 metres. Moving coil loud speaker. Walnut cabinet. Price, 17 guineas. TYPE U-106.—10 valve (including rectifier and tuning beacon) all-wave superhet. for A.C. mains. Six wave ranges, 4J- 2,000 metres. 12 watts output. High fidelity moving coil loud speaker. Massive walnut cabinet. Price, 25 guineas. TYPE CU-355.—5 valve (including rectifier) all-wave Console superhet. for A.C. mains, three wave ranges, 16-2,200 metres. Moving coil loud speaker. Walnut cabinet. 17 gns. TYPE CU-225.—6 valve (including rectifier) all-wave Console superhet. for A.C. or D.C. mains (Universal). Wave range 16-2,140 metres. Moving coil speaker. 19 gns. TYPE RADIOGRAM 535.—5 valve (including rectifier) all­ wave superhet. Radiogram for A.C. mains, having three wave ranges, 16-2,200 metres. Moving coil loud speaker. Electric gramophone motor with automatic stop and start mechanism. Walnut cabinet. Price to be announced. Model with automatic record changer also available. TYPE RADIOGRAM 385.—8 valve (including rectifier and tuning beacon) all-wave superhet. Radiogram for use on A.C. mains. Three wave ranges, 16-2,200 metres. 6 watts output. High fidelity moving coil loud speaker. Electric gramophone motor with automatic stop and start mechanism. Walnut cabinet. Price to be announced. Model with automatic record changer also available. TYPE RGU-650.—7 valve (including rectifier and tuning beacon) all-wave Radiogram for use on A.C. mains. Wave coverage, 16-2,100 metres. 12-in. auditorium loudspeaker. Electric gramophone motor with automatic stop and start mechanism. Walnut cabinet. Price, 34 guineas. TYPE RGAU-650.—The above model also available with an automatic record changer. Price, 40 guineas. 104 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. Burndept, Limited, 85 Light Gun Factory, Erith, Kent. 85 Telephone : Erith 3080 (Private Branch Exchange). Telegrams : Burndept Erith.

The Burndept All-Wave models, which are a feature on this stand, have been designed to give an equally high standard of performance and reproduction on all wavebands. The cabinets arc of unusually fine design and construction. The Mobile receivers, which proved so popular last year, have been retained in our lists for the coming season. MODEL CN.218. BATTERY MOBILE RECEIVER. A 4-valve superheterodyne with full A.V.C. and self-contained aerial. Polished walnut cabinet with detachable carrier strap. Price, com­ pletely equipped with batteries, 11 Gns. MODEL CN.229. UNIVERSAL MOBILE RECEIVER. A 5-valve superheterodyne with full A.V.C. Works off any mains, A.C. or D.C.—any voltage between 180 and 250 volts, self-contained aerial. In walnut cabinet with detachable carrier strap. Price 12] Gns. MODEL CN.259. EIGHT-VALVE ALL-WAVE SUPERHETERO­ DYNE. For A.C. mains, catering for reception on all wavebands between 13.5 and 2,000 metres. The circuit includes H.F. Preselector, Triode- Hexode Frequency Changer. Pentode I.F. Double-Diode for A.V.C. and detection. Double-Diode for noise suppression. Special L.F. Pentode for L.F. and noise suppression. Electron-coupled output valve giving 5 watts output. Walnut cabinet of original design. Price 18 Gns. MODEL CN.266. BATTERY 4 BAND SUPERHETERODYNE. A battery-operated receiver for wavebands 15 to 51, 50 to 180, 175 to 580, and 750 to 2,000 metres, employing separate Triode Oscillator and Hexode Frequency Changer, Pentode I.F. Double-Diode Triode, Second Detector A.V.C. and L.F. Amplifier. Pentode output. Special high flux density moving coil speaker. Fitted in modern walnut cabinet of exclusive design. Price, complete with batteries, 10] Gns. MODEL CN.267. A.C. MAINS 4 BAND SUPERHETERODYNE. This model is the A.C. mains version of the Model CN.266 and is similar in appearance. Wave ranges, 13.5 to 51, 50 to 180, 175 to 580, 750 to 2,000 metres. Circuit includes Triode-Hexode Frequency Changer, Variable-mu Pentode I.F. Amplifier. Double-Diode Detector and A.V.C. steep slope Pentode giving 3 watts output. Price 10] Gns. MODEL CN.270. FOUR-BAND BAND-PASS BATTERY RECEIVER. This 3-valvc band-pass input receiver employs Variablc-mu Pentode Preselector H.F. stage tuned on all bands. Tuning covers 13.5 to 48.5, 75 to 210, 200 to 550 and 900 to 2,100 metres. Complete with battery and accumulator in well-designed walnut cabinet. Price £8 5s. Od. MODEL CN.271. FOUR-BAND BAND-PASS UNIVERSAL MAINS RECEIVER. . . This receiver is the A.C./D.C. version of the Model CN.270. Circuit includes Variable-mu Pentode Preselector H.F. stage tuned on all bands. Pentode Detector Resistance coupled to an output pentode. Valve rectifier. Price 9 Gns. MODEL CN.274 SUITCASE PORTABLE RECEIVER. A small portable measuring 11 in. x 7 in. x 10] in., weighing only 16] lbs. No external aerial or earth required. Permanent Magnet moving coil speaker. Scale is calibrated in wavelengths and station names. Complete with H.T. battery and accumulator. Case is covered with imitation pigskin, and two locks and keys are provided. Price £1 2s. 6d. MODEL CN.276. UNIVERSAL MAINS 4 BAND SUPERHETERO­ DYNE. This is essentially similar to the Model CN.267, but is designed for A.C./D.C. mains. Price 10] Gns. MODEL CN.281. 8-VALVE ALL-WAVE SUPERHETERODYNE CONSOLE. Incorporating the Model CN.259 chassis. A special 12 in. diameter energised moving coil speaker is fitted to faithfully handle the 5 watts output available. The cabinet is designed on modern lines and finished in walnut. Price 23 Gns. MODEL CN.285. 8-VALVE ALL-WAVE SUPERHETERODYNE RADIOGRAMOPHONE. For A.C. Mains operation, incorporating Automatic Record-Changer. 106 svT-'-'" o •SI

Specialists In . . .

MODERN EXHIBITION

STAND FURNISHING

APPOINTED OFFICIAL FURNISHERS TO THE

PRINCIPAL LONDON AND PROVINCIAL EXHIBITIONS

CHARLES COOK’S FURNISHING STORES LTD. 71 HAMMERSMITH ROAD, W.14 OPPOSITE OLYMPIA

TELEPHONE FULHAM 0084-5-6 106 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Tannoy Products 86 (Guy R. Fountain, Ltd.), 86 Canterbury Grove, West Norwood, London, S.E.27. “ The Sound People ” are exhibiting Radio and Power amplifying equipment for all purposes, including :— PUBLIC ADDRESS AMPLIFIERS : with outputs 5 and 200 watts (undistorted). Particular attention is drawn to the range of self-contained gramophone-amplifiers, having outputs up to 50 watts. These are extremely compact and are easily transportable. These amplifiers are robustly constructed and are designed to operate successfully under the most arduous conditions of service. LOUDSPEAKERS exhibited on the TANNOY stand, include a full range of box baffle and baffle types designed for indoor use. The larger models for use with heavy output amplifiers are capable of delivering great volume with reproduction of great fidelity. PROJECTION LOUDSPEAKERS shown, include the specially designed TANNOY flat horn type which is suitable for the projection of speech or music over wide areas and for the majority of outdoor P.A. work, both mobile and stationary. MICROPHONES of all types are exhibited. Attention is drawn to the unusual and efficient design of these microphones, which have detachable heads enabling them to be used with floor stands, table stands, desk stands or handles, or any other type of mounting, as desired. RACK EQUIPMENT.—A comprehensive range of rack­ mounted equipment is shown, with and without Radio Panels, and gramophone turntables. This type of mounting is eminently suitable for Ships, Railways, Hotels, Clubs, / Hospitals, Institutions, Sports Grounds, and all types of r permanent or semi-permanent installations. RADIO GRAMOPHONES include types suitable for Schools, Hotels, Institutions, etc., and de-Luxe Radio Gramophones for Home use. In both classes, Record Changers are available and the Radio Chassis include the most up-to-date superhetero­ dyne receivers.

Baird Television, Ltd., 87 66, Haymarket, London, S.W.l and 87 Crystal Palace, London, S.E.19. Baird Television Limited—the recognised world pioneers in television—feature an entirely new range of receivers and equipment on their Stand. Brilliant pictures, freedom from distortion, excellent detail, wide angle of vision, extremely simple operation, and high fidelity sound are among the factors contributing to the first-class performance of all Baird Television receivers. Incorporating all the latest features in Television development, every model in the range represents the high-water mark of achievement, and includes Tree installation and one year’s service. Each television receiver incorporates a Baird “ Cathovisor ” Cathode Ray Tube which has the outstanding advantage of being completely electro-magnetic in operation. These tubes (Continued on page 100.) 107 =

muriEs RRDIO

SHORT WAVE LISTENING BECOMES A FINE ART When you take possession of a Milnes ;/ Onyx/7 battery superhet or " Venus/1 A.C. mains superhet, you make yourself master of the world’s radio. Not only have you medium and long waves—you have SIX FULL-SCALE RANGES OF SHORT WAVES. These are the sets which make short waves TWELVE TIMES EASIER TO TUNE and infinitely more interesting. Come to STAND 88 and examine the most advanced receivers at Radiolympia. “ONYX,” 5-valve battery superhet £14 5 0. “VENUS,” 6-valve A.C. mains superhet £15 15 0. “SATURN,” 4-valve battery superhet £8 16 0. “MERCURY,” 5-valve A.C. mains superhet £9 5 0. Valves specified for A.C. scls arc inclusive of rectifier. See also the famous MILNES H.T. SUPPLY UNIT—the unique, ever­ lasting, never-failing H.T. battery which recharges automatically from the L.T. and improves volume, tone and range of any battery set while cutting running costs to a fraction. munES RADIO CO. LTD. CHURCH ST. BINGLEY YORKS.

108 - Stand No. Grand Hall, Ground Floor. Stand No. Memoranda. - ] Baird Television, Ltd., 87 66, Haymarket, London, S.W.l and Crystal Palace, London, S.E.19. (Continued from page 107.) can be supplied separately with the necessary scanning equip­ ment where desired. Apart from the manufacturing processes, [ stringent tests are made for electrical emission, tube charac­ teristics, filament rating, and screen quality, and following normal picture reconstitution under service conditions, every Baird cathode ray tube, on completion, is subjected to a very high external pressure test. Baird “ Cathovisor ” cathode ray tubes are the ideal solution for high quality television pictures. Since a large number of Flat installations have been undertaken by the company, samples of the equipment used, together with a complete layout of a modern block of flats is shown. Vision and sound arc provided “ on tap ” in any room desired, and technical advice will be given by the company’s experts on all points. Another new development is the Baird Multiplier Photo-electric cell, of which there are two main types, suitable for either a concentrated light beam or diffused light. The Baird Multi­ plier is a chain of electron permeable grid stages, and under service conditions, current gain factors of the order of 100,000 can be obtained. Cathode sensitivity is approximately 30 microamps, per lumen. These Multiplier cells are suitable for all television and sound on film work, together with many industrial applications where high gain, coupled with sensitivity and extremely high signal to noise ratio is essential. Further examples of the manufacture of television equipment are featured, together with working models showing the principles of operation.

Milnes Radio Co., Ltd., I 88 Church Street, Bingley, Yorkshire. 88 A range of superheterodyne receivers comprises :— “ SATURN ” 4-valve battery superhet., short, medium and long waves. 600 milliwatts output. £8 16s. Od. “ MERCURY ” 5-valve A.C. mains superhet., short, medium and long waves, 3 watt output. £9 5s. Od. “ ONYX ” 5-valve battery superhet., six short, plus medium and long waves. H- to 2 watts output. £14 5s. Od. “ VENUS ” 6-valve A.C. mains superhet., eight wave ranges, 8 watts output, £15 15s. Od. Any model available in table or console cabinet. (Prices given are for table models.) Exhibits also include MILNES H.T. SUPPLY UNIT—pro­ viding H.T. current for any battery set and recharging auto­ matically from L.T. Also SP60 Charging Batteries, S/P Switch, Mains Chargers and many accessories. 10‘J % i# it 1 f f

In Uw morninn

READ■J -«v HjNUUS

HEWS CHROH .LE

Radio Critic

Your Set Works Better with AE R I A L I TE SPECIALITIES Aerialite ‘7-Strand’ pure copper AERIAL WIRE. The finest all-copper aerial wire Aerialite SUPER Aerial Wire obtainable. The covering is with ELEVEN Strands, and perfectly weatherproof. Needs ^P^JBLE thickness of the famous no insulators. 25 ft. 9d., 50 Aerialite insulation. £200 FREE ft. 1/6, 75 ft. 2/3, 100 ft. 3/- Lightning Insurance with each coil. 50 ft. 2/-, 75 ft. 3/-, 100 ft. 4/- Aerialite World-wide ALL-WAVE H.T. BATTERIES. DI-POLE AERIAL. TRAPEZE Complete with matched Aerialite Heavy-duty Dry Batteries, Aerial needs NO mast. transformer and glass insu- made by a special process, labora­ Easy to fix to wall or chim- lators. Specially designed tory controlled. 120- ney. No loose parts to to cut out inter­ volt,* long or square 4/11 cause crackle. Ideal for ference on short­ ALL-WAVE Sets. wave bands. 17/6 Complete with 40ft. Q / insulated down lead • f FLEXIBLE8 & CABLES. ASHTON Cables conform to B.E.S.A. specifications. Sizes fiA ^ up to 7/.064 in V.I.R., T.R., and Lead^Covered^ Cables, and

AERIALITE LTD. CASTLE WORKS, STALYBRIDCE, CHESHIRE

no Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Sound Sales, Limited, 89 Marlborough Road, Upper Holloway, N.19. 89 ! EXHIBITS ARE SPECIAL QUALITY AMPLIFIERS. The new 4-6 watt, 1938 4-12 watt model, 14 watt P.A. Amplifier with independent tone controls, new 28-34 watt Beam Ampli­ fier, rack and panel equipment (as supplied to public bodies). School Radio Equipment. Transverse Current Microphone. New S.S.38 combined Crystal Microphone and Pre-stage Amplifier. New folding Horn P.A. Speaker. Heavy duty Dual Suspension Moving Coil Sound Speakers. Special high quality radio equipment. Television transformers, chokes, and chassis as specified by the “ Wireless World.” Mains Transformers, Low Frequency Transformers, Straight Line Output Transformers, together with special Chokes of all types. Tuning Coils, Variable Selectivity I.F. Trans­ formers. Anti-Interference, equipment as supplied to the G.P.O. Battery Chargers.

90 Telsen Electric Co. (1935), Ltd., QQ I Fitzgeorge Street, Manchester, 9. ' The Exhibit comprises a wide range of Radio and Associated Apparatus, a short selection of which is listed hereunder :— RADIO INSTRUMENTS. 2-in., 2J-in., 3i-in., 4-in., 6-in., 8-in. Moving Coil and Moving Iron Voltmeters, Milliammeters and Ammeters, in bakelite or metal cases. 2 and 3 range Pocket meters. Multimeters. Counter Meters. Tuning Meters. SERVICE EQUIPMENT. Valve Testers. Universal Testers. Capacity Analiser. Multi­ range Instruments. Signal Generators. Chassis Cradles. MICROPHONES. Single Button. Transverse Current. Standard. Spring Sus­ pended. SPEAKERS. PICK-UPS. BATTERY CHARGERS. ELIMINATORS. SHORT-WAVE CONVERTERS. DIPOLE AERIAL KITS. TUNING CONDENSERS. REACTION AND DIFFERENTIAL CONDENSERS. SWITCHES. KNOBS. COILS.—Component and Manufacturers’ type. Short-wave coils. CHOKES.—H.F. and L.F. TRANSFORMERS.—Mains. Output. L.F. Microphone transformers. SUPPRESSOR PLUGS. RECTIFIER VALVE SAFETY ADAPTORS. ELECTROLYTIC CONDENSERS in Paper and Metal Con­ tainers. in SOUND C c<

J eouilMtffor

D

A New 0 Our Equipment is the best for Product. .SEE The L.S.8& P.A. WORK. 70" Horn TUBE BEST Handling P.A. Capacity 0Our Knowledge of P.A. the most 35 watts. - ^qui|iment LIST PRICE Comprehensive. Oil Horn £10 STAND Unit Remember also the large proportion £10 of Government Contracts we secure. I

Film Industries Ltd. HEAD OFFICE: 60 PADDINGTON STREET, W.l. 'Phone: Welbeck 2385 (4 lines).

2441

PRECISION COMPONENTS

It’s a standard. RsLdio e recognised and relied and a have Built Condensers des nt quality could create _ deca \s\on lete sliand ­lasting confidence. bo."’" a\ntancc renewing the acqu

and makingto that of new, V^e'°°\ct°r and to tr'iends. STAND

The All«Wave version of the ever- popular J.B. “Linacore" Tuner Unit, creator of Vivid Radio of an entirely i new order, is one of the many interesting new developments awaiting you on the J.B. Stand. JACKSON BROS. (LONDON) LTD., 72, ST. THOMAS' STREET, S.E.I.93 Telephone: HOP 1837. 112 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Q1 The Rawlplug Co., Ltd., Q1 S Cromwell Road, London, S.W.7. S JL Rawlplug Fixing Devices, including the well-known Rawlplug and Tools. Demonstrations will be constantly carried out. “ DUROFIX.”—The Heatproof, Waterproof, Acid-proof Adhesive for all Wireless Work. RAWLPLUG PLASTIC WOOD.—Wood in putty form for making good all defects in wood supplied in handy tubes or tins in all popular shades. ELECTRIC SOLDERING IRONS.—Supplied with inter­ changeable Bits. A real necessity for Wireless Repairs. “ FROSTOLAC.”—A decorative Lacquer providing a fascinat­ ing frosted effect for all surfaces in a wide range of attractive colours. Shaftesbury Microphones, Ltd., QO s 24, Aldersgate Street, London, E.C.l. S ^ Among special features of the Public Address Equipment exhibited are the following :— Amplifiers for high gain, for operation on A.C./D.C. mains ; output from 5 to 20 watts undistorted. MM/15 amplifier (2nd series) for operation on A.C./D.C. mains or 12-volt car battery, giving 15 watts undistorted output. 50-watt rack amplifier. Velodyne Supreme Velocity Ribbon Microphone \ a high output, high fidelity microphone shown together with portable amplifying equipment specially designed to operate with it. Among the loud speakers exhibited is what is believed to be the largest ever shown at Radiolympia \ this is of the patented Mono-Plana type and various other sizes of this type of speaker are also shown. Qq Jackson Bros. (London), Ltd., Qq y \J 72, St. Thomas Street, London, S.E.l. J An exhibit of a complete range of VARIABLE CONDENSERS and DRIVES, incorporating all types of single and ganged Condensers, not the least interesting of which is a special Ganged Condenser of very small dimensions to meet modern requirements. An extensive display of Drives and Dials ranging from the Vernier Dial to the latest Arcuate, Baseboard and Full Vision Dials, and to complete the series a Universal Linacore, which is suitable for A.C., D.C., and Battery operation. Qzl British Mechanical Productions, Ltd., QA. y+ 79a, Rochester Row, Westminster, S.W.l. ^ ® VALVEHOLDERS. — Chassis - Mounting types, English, American, Continental and short-wave models. Short-wave Baseboard types, leg supported. TERMINALS, Screw. TERMINALS, Spade, Hook, Ring. WANDER PLUGS. CONNECTORS. VALVE-PINS. CHASSIS-MOUNTING STRIPS. VOLTAGE SELECTOR PLATES. PLUGS AND SOCKETS (Radio). ' PLUGS AND SOCKETS (Electrical). LOUD SPEAKER CONTROL PANELS. 113 E Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

Gordon Elf, Ltd., 17a, Hanover Square, London, W.l. 95 Mayfair 5338 (2 lines). SPENCER CAMEO.—A.C./D.C. Mains Portable Receiver.— Self-contained Aerial, Superheterodyne circuit, Moving coil speaker, A.V.C., etc. £8 18s. 6d. BATTERY SUPERHETERODYNE. — Suitcase Portable, A.V.C., Automatic grid bias, Tone control, Moving coil speaker. Complete with Batteries. £10 10s. Od. ALL-WAVE RECEIVER.—Universal A.C./D.C. Receiver. Self-contained aerial, Moving coil speaker, A.V.C., High Q coils, 10—2,000 metres. 12\ guineas. BOOKCASE RADIOGRAMOPHONE.—Self-contained. A.C./ D.C. mains operated Superheterodyne circuit. Garrard electric motor. Cabinet designed as low bookcase. Various finishes. £25 4s. Od. TABLE RADIO GRAMOPHONE.—Superheterodyne circuit, Energised moving coil speaker, A.V.C., Tone control, Universal A.C./D.C. mains. Self-contained aerial. Fully portable. £15 15s. Od. All the above Receivers manufactured under Marconi Patents and utilising B.V.A. valves.

07 Regentone Products Ltd., 07 S ■ Regentone Works, Worton Road, Isleworth, Middx. " Wireless Receivers. Radiogramophones. Component Parts. Electric Converters. Mains Units.

G.P.O. Exhibit Electrical Interference. An exhibit by the G.P.O. illustrating various types of electrical interference with broadcast reception and the methods adopted for its diagnosis and cure. For full particulars see page 153.

114 Stand No. Grand Halt., Ground Floor. Stand No. Memoranda. Varley 99 (Oliver Pell Control, Limited), 99 Cambridge Place, Burrage Road, Woolwich, S.E.18. A special feature of components displayed is a new Three-band 2-Gang Tuning Coil Unit covering a range of 17—51 metres on the short waves and assembled in a very convenient form for the Amateur Constructor. Additions have been made to the range of Push-Pull Output Transformers. Tuning Coils and I.F. Transformers for the use of manufac­ turers and service engineers form a prominent part of the components on display. Other well-known components displayed are :— TUNING COIL UNITS. DUO-NICORE COILS. I.F. TRANSFORMERS. AIR TUNE I.F. TRANSFORMERS. PERMEABILITY TUNERS. H.F. CHOKES. VOLUME CONTROLS. WIRE WOUND. RESISTANCES. L.F. TRANSFORMERS. L.F. CHOKES. MAINS TRANSFORMERS. PUSH-PULL TRANSFORMERS. POWER POTENTIOMETERS.

1 HO Fuller Accumulator Company 1 Aft AUU (1926), Limited, Woodland Works, Chadwell Heath, Essex. The display of Fuller Low Tension Accumulators contains many points of particular interest, especially on the question of design and construction. The range is very comprehensive, including the well-known “ Mammoth ” series also “ Standard ” and “ De Luxe ” types together with an enlarged range of Free and Jelly-acid Unspillable types. Special exclusive features are embodied in the entire range ; these are :— (a) Patented Double Grease Cup Terminals which prevent corrosion of leads and terminal fittings. (b) Non-interchangeable terminals. (c) Indestructible Separators. (d.) High-capacity hand-pasted plates, etc., etc. Typical examples of the greatly increased range of Special Portable H.T. Dry Batteries are also displayed. This series now contains replacement batteries for every popular Radio Receiver, and in addition there are the usual standard types of H.T. batteries with prices ranging from 6s. per 120 volts upwards. Grid Bias batteries and Special Inert H.T. and L.T. Batteries (the latter specially suitable for tropical use) are also exhibited. 115 e 1 COLLARO AUTOMATIC RECORD CHANCERS

AUTOMATIC RECORD PLAYERS ELECTRIC AND SPRING GRAMOPHONE MOTORS RADIOGRAM UNITS

MAGNETIC AND CRYSTAL PICK-UPS

STAND MAIN NO. HALL 101 V

THE COLLARO AUTOMATIC RECORD CHANGER

sets an entirely new and higher standard in Record Changer per­ formance. It plays 9 inch, IO inch and 12 inch records mixed in any order without adjustment, and has also the following distinctive features :

1. Simplicity of loading. 6. Mechanism stops after last record or at 2. Silent Changing. any time on pressing “stop” knob. 3. Automatic biasing of pick-up, timed to avoid side pressure on 7. Single records may be played. record grooves. 4. Vertical lift to pick-up to obviate 8. All parts are produced to fine limits and undercutting of grooves. rigid specifications and each Changer 5. Any record may be repeated or is thoroughly tested and dependable rejected. for trouble-free service.

Full information and descriptive literature from

COLLARO LIMITED, CULMORE WORKS, CULMORE ROAD, PECKHAM, LONDON, S.E.15. Telephone: Telegrams: NEW CROSS 2050 (3 lines). KORLLARO PECK, LONDON.

116 : Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

| Collaro Limited, 101 Culmore Works, Gulmore Road, Peckham. 101 The COLLARO Automatic Record Changer which plays eight 9-in., 10-in., and 12-in. diameter Records mixed in ! any order without adjustment. The COLLARO Automatic Record Player (Letter-box type) Chassis or fitted into Console and Lowboy cabinets. The COLLARO A.C. 37 Induction Motor for A.C. Mains. The COLLARO U.36 Universal Motor for A.C. and D.C. Mains. The COLLARO Magnetic Pick-up. ' The COLLARO Crystal Pick-up. COLLARO Radiogram Units embodying the A.C. 37 and U. 36 Motors combined with COLLARO Pick-ups on beaded- edged and rectangular unitplates, with automatic start and stop. The COLLARO A. 30 and B. 30 Single and Double Spring Gramophone motors.

1 Geo. Tucker Eyelet Co., Ltd., 1 f)0 X \J hr* Cuckoo Road, Birmingham, 7. A-\J6* An exhibit illustrating a few of the more popular lines from our extensive range of eyelets, solder tags, connections and battery caps. Special attention is drawn to the various finishes, in particular, the hot tinned and silvered finishes. Another feature is the pure nickel valve eyelets which are made from 99.9 per cent, pure de-gassed nickel. We are always anxious to make lines to suit customers’ require­ ments, and shall be glad to quote for any small metal press- wares of any shape.

Ace Radio Ltd., 103 2-5, Dingley Place, City Road, E.C.l. 103 ALL-WAVE SUPERHETERODYNE RECEIVERS. ACE Model AW53B 4-valve three wave-bands Battery Super­ heterodyne. 9 guineas. ACE Model AW53 AC. 6-valve three wave-bands A.C. Mains ■ Superheterodyne, 200-240 volts, 40-100 cycles. 9h guineas. ACE Model AW53 UNI. 6-valve three wave-bands A.C./D.C. mains Superheterodyne, 200-240 volts. 9£ guineas. ACE Model AW73 AC. 7-valve three wave-bands A.C. mains Superheterodyne, 200-240 volts, 40-100 cycles, 12 guineas. ACE Model AW73 UNI. 7-valve three wave-bands A.C./D.C. mains Superheterodyne, 200-240 volts. 12 guineas. ACE Model AW94 AC. 9-valve four wave-bands A.C. mains Superheterodyne, 200-240 volts, 40-100 cycles, 15 guineas. ACE Model AW94 UNI. 9-valve four wave-bands A.C./D.C. mains Superheterodyne, 200-240 volts. 15 guineas. ACE Model RG7 AC. 7-valve three wave-bands A.C. mains Super­ heterodyne Radiogram 200-240 volts, 40-100 cycles. 21 gns. ACE Model RG7 UNI. 7-valve three wave-bands A.C./D.C. mains Superheterodyne Radiogramophone, 200-240 volts. 22 gns. ACE Model RG9 AC. 9-valve four wave-bands A.C. mains Super­ heterodyne Radiogram, 200-240 volts, 40-100 cycles. 25 gns. ACE Model RG9 UNI. 9-valve four wave-bands A.C./D.C. mains Superheterodyne Radiogramophone, 200-240 volts. 26 gns. 117 Stand No. Grand Hall, Ground Floor. Stand No. Memoranda.

1 Q4 Dynatron Radio Ltd., 1 f)A ^ * Perfecta Works, Ray Lea Road, Maidenhead, -A. V/ i Berks. New Range of Dynatron All-Wave High Fidelity Radio Gramo­ phones and Receivers. The ETHER EMPRESS Radio Gramophone, the Supreme Reproducer. 16 valves with 15 watts output. Alternative Model with Voigt Speaker. The ETHER PRINCE ALL-WAVE Radio Gramophone 12 valves, 8 watts output. The ETHER KNIGHT ALL-WAVE Radio Gramophone, faithful reproduction at a reasonable cost. The ALBATROSS ALL-WAVE Console Receiver. The CONDOR ALL-WAVE Console Receiver. 12 valves. All completely new models and featuring the Dynatron Visible Tuning Dial that illuminates the actual station name on tuning. All-wave reception on 5 wavebands from metres to 2,000. True flat topped variable selectivity.

“Radio Pictorial." 105 Television and 105 Short-Wave World.” Bernard Jones Publications Ltd., 37/8, Chancery Lane, London, W.C.2. Telephone : Holbom 6158 (8 lines). Telegrams : Beejapee. “ RADIO PICTORIAL,” every Friday, price threepence. The magazine for every listener, giving all the week’s radio news, gossip and pictures. “ RADIO PICTORIAL ” carries exclusively all the English-spoken programmes from Conti­ nental stations, and contains each week numerous brilliant articles on programme personalities and radio topics of the hour. In addition, several pages each week are devoted to women’s and children’s interests. “ RADIO PICTORIAL ” completes your radio enjoyment. The August 20 and August 27 issues of “ RADIO PIC­ TORIAL ” form a COMPLETE PICTORIAL SOUVENIR of RADIOLYMPIA, containing numerous special articles about the Exhibition, the shows and the broadcasts, all lavishly illustrated. “ TELEVISION AND SHORT-WAVE WORLD.” A monthly journal published on the last Wednesday of each month, price Is. Special Exhibition number on sale. “ TELEVISION AND SHORT-WAVE WORLD ” is the first television journal in the world and the recognised authority. It deals with all the new developments in tele­ vision and caters for both professional and amateur. Home construction of television receivers was first made practicable for the amateur through the medium of its pages. A special section of each issue of “ TELEVISION AND SHORT-WAVE WORLD ” is devoted to the interests of short-wave enthusiasts and embraces both transmission and reception. Complete constructional details of short-wave transmitters and receivers are given in practically every issue and it is the only journal that caters so comprehensively for the short-wave amateur. On view on this Stand will be examples of television and short-wave apparatus and a member of the staff will be in attendance. 118 MANUFACTURERS’ SUPPLIERS’ SECTION.

GRAND HALL: GALLERY. Stand No. Grand Hall, Gallery. Stand No. Memoranda.

R. O. Bridger & Go., Ltd., 4, Shelford Place, Church Street, N.16. Manufacturers of Seamless Moulded Paper Cones for Moving Coil Loud Speakers and Microphones. 151 The Bifurcated & Tubular 151 Rivet Co., Ltd •5 Aylesbury, Bucks. A display of Rivets, Eyelets and Soldering Tags suitable for Radio construction. A display of samples of work which has been riveted on our machines. Illustrations of our various types of machines are available, together with expert advice on all riveting problems.

152 ^teat^te & Porcelain Products ^2 Limited, Stour p ort- on- S evern, W orces ter shire. (Associated with Imperial Chemical Industries. Ltd.) London Office: Thames House, Millbank. S.W.l. FREQUENTITE AND FARADEX (Registered Trade Names). Of interest to all Transmitter, Receiver and Component Manu­ facturers. A visit by all Radio Engineers is recommended. On this Stand can be seen the ceramic low dielectric loss material, FREQUENTITE, and the high permittivity material, FARADEX. The advantages in using these materials will be fully explained by technical representatives, and illustra­ tions of their adaptability to all requirements for High Fre­ quency applications can be seen. A full range of exhibits incorporating these materials are shown, including :— Coils for all applications. Bases—Trimmer, Padder, Fixed, etc. Switches. Valve Bases and Holders. Tubes and Rods. Bushes and Washers. Beads for bare wire insulation. A range of large insulators for Radio transmission. 119 MIGA & MICANITE SUPPLIES LIMITED, MICA HOUSE, BARNSBURY SQUARE, LONDON, N.l.

MICA MERCHANTS AND MANUFACTURERS of Mica, Micanite and Bakelite Parts for every section of the H RADIO AND ELECTRICAL INDUSTRY

t Low Loss Condenser Plates : Valve Bridges Diaphragms Washers Stampings Commutator Sections i Armature Bands ■

Block Mica Mica Splittings Ground Mica J I

BAKELITE MICANITE

Sheet : Stampings Hard Brown : Moulding Coil Formers Pierced Flexible : Commutator and Screwed Formers Heat Resisting : Tubes Tubes Mouldings

QUALITY • PRECISION * SERVICE

Telephones : Telegrams : North 3032-3-4. Micasulim, Nordo, London. A.B.C. 5th BENTLEY’S MARCONI’S INTERNATIONAL.

120 ■ i Stand No. Grand Hall, Gallery. Stand No. Memoranda.

1 British Gentralab Ltd., 1 C"! Canterbury Road, London, N.W.6. -LOO CENTRALAB Volume Controls.

Mica&Micanite Supplies Ltd., ^^4 Barnsbury Square, London, N.l. Block Mica and Mica Splittings. Mica Condenser Plates, Valve Bridges and Stampings. Lamalac (Bakelite) Sheet, Stampings, Coil Formers, Pierced and Screwed Formers. Micanite Sheets, Tubes and Mouldings.

A. H. Hunt Limited, 155 Bendon Valley, Garratt Lane, Wandsworth, 155 S.W.18. Manufacturers of Hunt’s Fixed Condensers, Paper Mica, Wets and Dry Electrolytics, Trimmers. Also special testing gear, including the capacitor analyser and signal generator. Also makers and stockists of exact service replacement condensers for the majority of sets serviced. Suppliers of Fixed Condensers to the majority of British Set Makers and to the principal countries of the world.

| The Scott Insulated Wire Co., Ltd., ^^6 Queensland Works, Holloway, London, N.7. SCOTT Silk Insulated Wires. SCOTT Cotton Insulated Wires. SCOTT Enamel Insulated Wires. Instrument Wires in Copper and Resistance. The Exhibit will include some of the component materials illustrating the world-wide resources necessary in the produc­ tion of SCOTT INSULATED WIRES. Some of its uses will be illustrated by exhibiting a few instruments in which it is used.

|Cy May & Baker Limited, 42/43, St. Paul’s Churchyard, London, E.C.4. RHODOID Scales, Dials and Moulded Component Parts are shown, together with special qualities of this cellulose acetate material for the protective choke and coil covering and insula­ tion purposes. RHODOID is available in a wide range of colours and thick­ nesses, transparent, translucent and opaque.

1 CO British Metal Engraving 1 CQ 100 Company Limited, 100 St. Margarets Works, St. Margarets, Middx. Wireless Scales, Dials and Name Plates, in Metal, Glass, Ivorine and other materials. 121 IN ADDITION TO

CAREFULLY SELECTED

WIRELESS PROGRAMMES THE

WORLD GIVES YOU

THE MOST INTERESTING

NEWS OF THE DAY

ALL THE SPORT

TRY A RESTFUL WEEK-END WITH THE WORLD'S FAVOURITE PAPER

READ IN 4,000,000 HOMES EACH SUNDAY

122 Stand No. Grand Hall, Gallery. Stand No. Memoranda.

1 CQ Rist’s Wires & Cables Ltd., 1 CQ ' Waveney Works, Lowestoft, Suffolk. A.kJ^7

“ Super-Range ” Aerials.

7/25 Aerials.

Twin Flat Extension Cord for Loud Speakers, etc., Art Silk or Glace Cotton.

Wireless Lead-in Wires.

Screened Tubing.

Wireless Flexibles.

Screened Flexible Conductors.

Pushback Connecting Wires.

Mains Leads, Wiring Assemblies, etc., made to specifications and drawings. TUNGSRAM

for long life

and reliability

THERE IS A TUNGSRAM VALVE FOR EVERY

TYPE OF RECEIVER

TUNGSRAM Barium VALVES THE VALVE WITH THE NAME BEHIND IT!

Manufactured in Tottenham, London.

STAND NO. 36—GROUND FLOOR

123 •ra

mMp s*'

A long-felt want has been met by this new RADIO SERVICE MANUAL written by the well-known authority on Radio, Mr. Percy W. Harris, Mem.I.R.E. and published by The Radio Manufacturers’ Association. An idea of its scope and possibilities may be appreciated by this extract from the Preface c< A thorough grasp of the contents of this book, if applied to everyday experience, should help very considerably towards raising the standard of the average Service Marts technique. To all engaged in the Radio Industry this book is strongly recommended as the most authentic up-to-date expose of the requirements of the modern Service Man."

Obtain your copy from the R.M.A. Information Bureau Stand No. 40, or write to The Radio Manufacturers’ Association, Astor House, Aldwych, London, W.C.2 direct, enclosing 3/6 plus 8d. to cover cost of postage and packing. THREE COPIES SENT POST AND PACKING FREE.

124 INSTRUMENT SECTION.

GRAND HALL: GALLERY.

Stan d No. Guano Hall, Gallery. Stand No. Memoranda.:

The Mullard Wireless Service 161 Co., Ltd., 161 225, Tottenham Court Road, W.l.

The range of “ Mitcham Instruments ” displayed on this stand has been specially designed on factory test principles for radio service dealers.

The apparatus includes Valve Test and Receiver Analysis Boards, Oscillators, Measuring Bridges and Cathode-ray Oscillographs.

Practical demonstrations of all instruments can be arranged on request.

Radiometers Ltd •> 162 Eagle House, Jermyn Street, S.W.l. 162

THE ALLVALVE TESTER, TYPE “ UVeT.”—This instru­ ment enables both emission and mutual conductance of British and American valves, including A.C./D.C. and side-contact types, to be checked against standards given in Data book with each instrument. Provision is also made for checking inter-electrode insulation. Data book gives readings for over nine hundred valves. Price £8 8s. Od. nett. 200/250 volts A.C. only. 40-60 cycles. Other voltages on request.

The ADAPTOR PANEL used in conjunction with the ALL­ VALVE TESTER accommodates British and American Octal valves, also British midget valves, and all others. Spare sockets are available for future needs. Complete with separate Data book. Price £2 10s, Od. nett.

THE “FARADOHMETER” RESISTANCE and CAPACITY MEASURING BRIDGE, with visual indication and directly calibrated dial, checks resistances from 50 ohms to 4 megohms, in two ranges, and capacities from .00005 to 25 microfarads. Supplied either as a portable model, with self-contained batteries, or as an accessory to work from the ALLVALVE TESTER thus dispensing with batteries. Price (either model), £5 5s. Od. nett. 125

Stand No. Grand I-Iall, Gallery. Stand No. Memoranda. A. C. Cossor, Ltd., 163 Cossor House, Highbury Grove, London, N.5. = 163 The Cossor exhibit on Stand No. 163 embraces a range of 3 Cossor Cathode Ray Tubes and Instruments, including Oscillographs, Cameras and Amplifiers for Cathode Ray Recording and Test and Aligning Equipment for the compre­ hensive servicing of Radio and Electrical apparatus. OSCILLOSCOPE MODEL 3332.—A complete laboratory equipment in compact portable form for use on Radio and * . Electrical Test work. It uses a 4J-in. diameter Cathode Ray Tube. Its specification includes High Voltage power pack, Signal Amplifier of 26 db. gain covering 20 to 100,000 c.p.s., multi-range Deflector Coils permitting A.C./D.C. measurements of from 1 m.a. to 3 amps., Mumetal shield against electro-magnetic interference, Synchronising, Shift and Calibrating circuits and ruled scale. The sensitivity is 15 m.m./v. A Camera specially designed for use with this Oscilloscope is also shown. GANGING OSCILLATOR MODEL 3343.—An instrument indispensable to Servicemen for the visual alignment of the H.F. and I.F. Circuits in Radio Receivers. A band of from 90 Kcs. to 20 Mcs. is covered in 5 steps. It is both Frequency and Amplitude Modulated (Standard 400 cycle note). OSCILLOGRAPH Model 3363.—The largest instrument of this type constructed ; primarily designed for laboratory use and incorporating a 12-in. diameter Cathode Ray Tube, Power Pack and Hard Valve Type Time Base. TRIPLE TUBE UNIT MODEL 3314.—An equipment designed forjthe simultaneous recording of three distinct correlated phenomena. This unit is displayed with the Film Camera Model 3318 and Drum Camera Model 3317 for use therewith. OSCILLOGRAPH AMPLIFIERS. AUDIO AMPLIFIER MODEL 3319.—Designed for ail A.F. recording. The exhibit is shown complete with Microphone. PARAPHASE D.C. AMPLIFIER MODEL 3355.—This instrument is designed for the recording of a wide frequency range from zero to 100 Kcs., and is eminently suitable for the investigation of pressure problems. The exhibit shows the Amplifier in use with Pressure Unit Model 3305, Bridge Element Model 3358, D.C. Pre-amplifier Model 3326 and a High Vacuum Cathode Ray Tube Unit Model 3313. CATHODE RAY TUBES.—A complete range of Cossor Cathode Ray Tubes of the Gas Focused and High Vacuum Types, Directly Heated Tubes for Oscillography and examples of the new Indirectly Heated Television Tubes are displayed in finished and separate electrode assemblies.

1 64 Everett, Edgcumbe & Co., Ltd., 1 f.A ■ Col indale Works, Hendon, London, N.W.9. -LV-J ■ “ Radiolab” Testing Equipment for Dealer, Factory and Laboratory use. “ All-purpose ” Tester, Set Analysers. “ All Wave ” Oscillators, Output Meters. Audio Frequency Oscillator. “ Visual ” Valve Tester and “ Service ” Valve Tester. “ Radiolab ” Valve Gauge. Ammeters, Voltmeters, Wattmeters for A.C. and D.C. Ohmeters. 127 Stand No. Grand Hall, Gallery. Stand No. Memoranda.

1 Wright & Weaire Limited, 1 740, High Road, Tottenham, London, N.17. Testing Instruments for Radio Service Engineers in convenient units and standard size, consisting of:— Valve Testing Unit. Meter Unit. All-Wave Oscillator Units', Battery and A.C. models. Condenser Analyser Unit. Lamp and Iron Testing Unit. Instrument Dials. Accessories for Radio Service.

The Automatic Coil Winder & 166 Electrical Equipment Co., Ltd., 166 Winder House, Douglas Street, London, S.W.l. Avo Capacity Meter, £23 Os. Od. Model 7 Avometer, £16 16s. Od. Resistance Range Extension Unit for above, 10s. Od. Universal Avometer, £13 13s. Od. Avo Valve Tester, £11 11s. Od. Extra panel for above (if required), £2 2s. Od. Avometer D.C. Model, £9 9s. Od. Avo-Oscillator Universal Avominor, £5 10s. Od. D.C. Avominor, £2 5s. Od. Avo Exposure Meter, £3 3s. Od. I Avo Light Meter, £2 5s. Od. AvoDapter, £1 7s. Od. Smethurst High-Light Exposure Meter, £4 4s. Od. “ AVO ” Testing Accessories, 2s. 6d. “ RADIO SERVICING SIMPLIFIED.”—A comprehensive text book. 6th edition. Revised and enlarged. COIL-WINDING MACHINES. “ Douglas ” Fully Automatic Multi-winder, with paper inserter.

Weston Electrical Instrument 167 Co., Ltd., 167 Kingston By-Pass, Surbiton, Surrey. The Weston Stand will, as usual, consist of an exhibit of instru­ ments designed especially to meet the requirements of the Radio Service Engineer. In addition to the Analyzer and Oscillator as made in other years Weston will exhibit its new Super-Sensitive Analyzer for the first time. The Super-Sensitive Analyzer contains all the features of the well-known Model E.665 Analyzer. A brief summary is as follows :—Voltage ranges 0-2.5 up to 0-1,000, all D.C. ranges 20,000 ohms per volt, all A.C. ranges 1,000 ohms per volt; resistance measurements from 30 megohms to 0.1 ohms all with self-contained battery ; scale nearly twice as long as the Model E.665 ; A.C. current ranges 5, 1, 0.5 amperes ; D.C. current ranges from 0-500 milliamperes to 0-100 microamperes. The new Super-Sensitive Analyzer is described as WESTON MODEL 772. 128 i Stand No. Grand Hall, Gallery. Stand No. Memoranda.

1The Salford Electrical 1 AQ Instruments, Ltd., Peel Works, Silk Street, Salford, 3.

“ Q ” METER.—Direct reading, mains operated, portable for Q and frequency. Q values from 25 to 500, frequency 100 to 6,000 K.C. per second. i i “ L ” METER.—Similar to above. Range 1 to 5,000 U.H.

“ C ” METER.—Similar to above. Range 0 to 100,000 U.U.F.

RADIO CORES.

MINIATURE INSTRUMENTS, including MULTI-RANGE TEST SET.

RECTIFIER INSTRUMENTS FOR RADIO FREQUEN­ CIES.

VALVE VOLTMETERS.

Why not take up WIRELESS as a ‘ Worthwhile ’ Career ? THE BRIGHTEST SPOT IN BRITISH INDUSTRY We train students for all branches of the Wireless Profession : Marine, Aircraft, Broadcasting, Manufacturing, Designing, Experimenting, Sales, Service, etc., etc. Men who foresaw the Broadcasting boom made good— Be trained and prepared for the Television boom which must follow as surely as day follows night. MARCONI’S anticipate requiring, many new wireless operators during the next few years. Training period 8/12 months. APPOINTMENTS GUARANTEED. —— TRAINING FEE CAN BE PAID AFTER APPOINTMENT MANUFACTURERS, IS SECURED. RETAILERS, Students accepted as Boarders. SERVICE PROSPECTUS POST FREE. ORGANISATIONS, THE THE etc., WIRELESS COLLEGE, WIRELESS COLLEGE, COLWYN BAY, CALMORE, Southampton. Estate of 16 acres overlooking1 should apply to us NORTH WALES (On 8oa Front). for staff require­ Southampton Water. ments. We supply Britain’s Largest Wireless Training Centres. highly trained men. Our London Representative at 4, Winton Avenue, N.U, will be No fees. Please state pleased to meet you anywhere in town, without obligation. requirements.

129 tAlffl

Radio Notes

AND

SOLDER TAGS

A wealth of experience in eyelet and solder tag manufacture is behind, every line we make. We specialise in the production of all shapes, sizes and ' finishes, including hot-tinned, and we are organised to give prompt deliveries. Send for Catalogue, samples and prices.

geo. TUCKER EYELET co. ltd. CUCKOO ROAD i STAND : BIRMINGHAM 7 i j 102 ’PHONE: EAST 0441-2-3. ’GRAMS: " EYELETS, B’HAM.” Shaw

130 GENERAL EXHIBITS.

GRAND HALL: GALLERY.

Stand No. Grand Hall, Gallery. Stand No. Memoranda.

Of) 1 Barratt & Robinson Ltd., Of) 1 L*\J ± 288-310, York Road, King’s Cross, N.7. ±-

Will be exhibiting Player Pianos, Miniature Pianos and Music Rolls.

A fine range of modern instruments will be on show, including the Smallest Grand Piano in the world, and the smallest Player Piano.

OHO Crypton Equipment Ltd., 0f)0 North Acton Road, Park Royal, N.W.10. w

CRYPTON BATTERY CHARGING RECTIFIERS.

A complete range of up-to-date models is exhibited, capacities ranging from 1.3 amps, to 15 amps.

CRYPTON CONSTANT VOLTAGE BATTERY CHARGERS.

Modern Battery Chargers for re-charging batteries in an average . of 8/12 hours.

CRYPTON BATTERY SERVICE APPARATUS, including Hydrometers, Thermometers, Cell Testers, Cadmium Testers, Water Distillers, etc.

Wireless Retailers’ Association 203 of Gt. Britain & N. Ireland, 203 10, Ashley Place, Westminster, S.W.l.

Lounge for dealers, with office facilities including telephone.

An executive of the association will be in attendance at all times for those who wish to discuss trade matters. 131 act ever staged! Do you re­ member it .. . and all the interest that centred about the Eavestaff Stand? THIS YEAR / SOMETHING EVEN BETTER! / B Apart from the complete range of fascinating new models, several finished in beautiful rare woods . . . something as revolutionary as the invention of the “ Minipiano” itself . . . the introduction of another Eavestafftriumph—the “Minigrand.” See it on the Eavestaff Stand, graceful and modern in line . . . hear the lovely rich tone, equal in every way to that of a Baby Grand . . . admire its many patent features, particularly the novel method of opening. A musician’s instrument— the new “ Minigrand ”—and a thoroughbred in every line of its beautiful casework.

STAND No. 204

iJk eavestaff fianetie

THE 0RlG/NHL miNIflTURE PlfiNO W.G. EAVESTAFF & S0NS,LTD, ASHFIELD RD, HARR INGA Y, N.4. Car no Wilson. 132 ■

Stand No. Grand Hall, Gallery. Stand No. Memoranda.

204 W. G. Eavestaff & Sons, Ltd., 204 ■ Ashfield Road, Harringay, London, N.4. w w I Once again the Eavestaff “ Minipiano ” provides one of the many attractions of Radiolympia. This fascinating little instrument—the ORIGINAL miniature piano—full and resonant in tone, equally versatile in its rendering of serious or gay music, adapts itself charmingly to the needs of modern music-lovers. Last year the Eavestaff “ Minipiano ” caused a great sensation with an unique stage act in which fifty pianos took part at once. This year an even greater surprise is in store of a totally different nature. Apart from the full range of 6 and 7-octave “ Minipianos ” in every conceivable finish of maple, sycamore, walnut, oak and mahogany, besides the standard black and charming coloured models, an entirely new piano is being introduced—new in appearance, in design and construction—the Eavestaff “ MINIGRAND.” This amazing instrument, with an action and tone equal in every way to the average Baby Grand, is absolutely unique. It combines all the good qualities of the old-fashioned upright model with a grace of line and neat, compactness of design that will delight every eye. Nothing like the Eavestaff “ MINIGRAND ” has ever been shown before and every visitor to Radiolympia should not fail to see it. Altogether, the Eavestaff stand makes a very attractive exhibit, and the pianos themselves a very worthy addition to any modern home. Their superb tone and resonance and delight­ fully easy action have made the name Eavestaff famous in the piano world for over a century, and the fact that in two ! years the “ Minipiano ” became the largest selling piano in the world speaks for itself.

207 Norman Rose (Electrical) Ltd., 207 ■ 94, Tottenham Court Road, London, W.l. f I This exhibit is explained by the slogan of the Company, “ Service to Servicemen.” Comprehensive range of Electro­ i lytic Condensers, Resistors, Volume Controls, Solder Irons, range of Norman Test Equipment, including well-known “ Omnisection ” Valve Emission Tester, Pat. No. 453167, a tester on a new principle, requiring no technical knowledge or valve data, £4 10s. each. Norman 99 Radio Analyser, a unique instrument capable of making every test commonly used in the service room, 14 Gns.

20Q All-Power Transformers Ltd., 209 ' 8a, Gladstone Road, Wimbledon, S.W.9. S A number of new lines have been introduced by this firm, including Vibrator Units, L.T. Chargers and Eliminators. Small Transformers to Crown Agents Specifications will be of special interest, as well as the usual range of Power, Audio, and Line Transformers, Chokes, etc.

210 The 362 Radio Valve Co., Ltd., 210 ” 324/6, Liverpool Road, Highbury, N.7. w X. V7 Radio Valves, especially Transmitting and Public Address types. Also appropriate Circuit Designs for demonstration of correct use of the valves. 133 Specialising in the manufacture of—

DYNAMIC and CARBON MICROPHONES

POWER LOUDSPEAKER UNITS, using unbreakable Balsa Diaphragms

METAL HORNS SOUND RESLO( EQUIPMENT ) LTD. offers the Public Address Industry better products that are guaranteed with­ STAND No. out qualification.

97, Hampstead Road, EUSTON 3558. LONDON, N.W.l.

THE RADIO SOCIETY OF GREAT BRITAIN PRESENT------

A GUIDE TO AMATEUR RADIO” The FIFTH and ENLARGED EDITION of this Annual Handbook is now available from STAND OVER ISO PAGES OF UP-TO-THE-MINUTE SHORT WAVE INFORMATION. 214 EIGHTEEN CHAPTERS : Television—Transmitters—Valves—Receivers—Aerials—Ultra High Frequencies—Measuring Instruments—Fundamental Principles— Power Supplies—Frequency Meters—Selected References—Morse Code—International Prefixes and Abbreviations—Valve Data— Useful Formulae—Artificial Aerials. PRICE COPIOUSLY ILLUSTRATED-WELL PRINTED. Written by and for Radio Amatears. 6d- 45,000 copies of previous editions sold. Post free 8d. ORDER OR COLLECT YOUR COPY TO-DAY. Full details of Membership from the Secretary, RADIO SOCIETY OF GREAT BRITAIN, 53, VICTORIA STREET LONDON, S.W.I

134 Stand No. Grand Hall, Gallery. Stand No. Memoranda.

211 The British Pix Company Ltd., 211 *'*■“*■ 118, Southwark Street, London, S.E.l. wAX PIX Invisible Aerial, 30 ft., 2s. ; 60 ft., 3s. 6d. PIX Glass Lightning Arrestor, with £1,000 Free Insurance. The PIX for Selectivity, 2s. ; with holder, 2s. 6d. PIX Metallised Earth, 2s. GRIPON Self-fitting Aerial, with two Cloche Insulators and 50 ft. Tubular Aerial, 4s. 6d. ; with 70 ft. Tubular Aerial, 5s. 6d. ; with 100 ft. Tubular Aerial, 6s. 6d. MAGNATONE Tubular Aerial, for long distance, 16-strand copper strip, 100 ft., 6s. ; 50 ft., 4s. PIX Valves from 2s. 6d. 212 Radiolympia Museum. 212 This stand has been devoted to the collection and arrangement of a series of exhibits of historic interest in the progress of radio communication, from its early beginnings in the lab­ oratories of the scientists, to its present world-wide develop­ ment as a common factor in the life of Mr. and Mrs. Everyman. Further particulars of the exhibit are given on page 151. 21 'l Davis & Timmins Ltd., 21 3 JL*J Brook Road, Wood Green, N.22. X\J Manufacturers of Metal Thread Screws, both die cut and rolled threads in British Association and Whitworth sizes, including Nuts and Washers, in brass and all metals. Also Electrical Terminals, Cable Sockets, Conduit Bushes to B.S.I. Specifications, Small Wireless Components, Stampings and Presswork. Specialists in Screw Machine Products for the Electrical, Aircraft, Shipbuilding and general engineering industries. Large stocks are carried of all standard sizes of B.A. and Whitworth Screws, Nuts and Washers, in both die cut and rolled threads. On War Office, Admiralty and Air Ministry Lists. 21 A The Incorporated Radio Society 21 4. of Great Britain, 53, Victoria Street, London, S.W.l. Display of amateur-built Short Wave Receivers, Transmitters, Frequency Meters, etc. Fifth edition “ GUIDE TO AMATEUR RADIO,” com­ prising some 150 pages of technical information, including Television, available price 6d. Society literature, including T. & R. Bulletin (Official Journal), Call Books, Handbooks, etc., on sale. Membership particulars and advice free. ! Prominent amateurs in attendance. : 21 ^ Mercantile Credit Co., Ltd., 21 ^ " City-Gate House, 39/45, Finsbury Square, w A London, E.G.2. Mercantile Credit Company, Ltd., through its Associated Com­ panies, Bankers Commercial Security, Ltd, (The B.C.S. Plan) and The Equipment Trust Company, Ltd. (The T.E.T. Plan) offers Hire Purchase facilities for Manufacturers, Whole­ salers and Retailers. Facilities are also available for acquiring motor vehicles, alterations to premises, etc., on terms which make it unnecessary to disturb working capital. TRADE ONLY. 136 r

HIRE PURCHASE

finance & service

With a paid-up Capital of £1,093,750, Bowmaker Ltd. is one of the country’s largest organisations dealing in the modern form of hire purchase transactions and extended consumer credit. The supremacy of the Bowmaker hire purchase service is due to thc'unique Bowmaker branch organisation. The 35 branches cover every important centre of population in the country. Each acts as a Head Office. Each has power to make decisions independently. That is why settlements of approved transactions can be made immediately. When a proposal is submitted, the local branch will forward all the necessary information to the dealer on the same day—in urgent cases within a few hours. If you arc interested in this modern interpretation of hire purchase, you are cordially invited to call at the Bowmaker stand or to get in touch with your local branch (listed below).

Stand 211 ( G allery)

i BOWMAKER LTD. INDUSTRIAL BANKERS

London Office: 26 St. James’s St., S.W.l. Head Office: Bowmaker House, Lansdowne, Bournemouth. Branches at: Luton, Brighton, Croydon, Maidstone, Reading, Birmingham, Bristol, Carlisle, Exeter, Gloucester, Leeds, Leicester, Liverpool, Manchester, Newcastle, Norwich, Nottingham, Oxford, Plymouth, Portsmouth, Sheffield, Southampton, Truro, Edinburgh, Glasgow, Cardiff, Rhyl, Swansea, Belfast, Guernsey, Jersey, Dublin, Cork.

1,36 '

Stand No. Grand Hall, Gallery. Stand No. Memoranda.

21 fk Hillman Brothers, Ltd., 21 ^ Leeds and Sheffield. ^ For particulars of Exhibit see page 145.

217 Bowmaker Ltd. (Bournemouth), 217 " 26, St. James’ Street, London, S.W.l, w X f and Branches. Bowmaker Ltd. and its subsidiary Companies form one of the largest Groups in the United Kingdom, dealing with Hire Purchase Agreements and Industrial Credit in every modern form. Capital (fully paid, £1,093,750) with 36 branches in principal centres of the U.K. and Irish Free State. Each Bowmaker branch is a Head Office in itself and local managers are qualified and authorised to accept and effect IMMEDIATE settlement of approved transactions. Descriptive brochure, post free. 2|® Olds Discount Co. Ltd., 21S Equitable House, Nottingham, and Victoria House, Southampton Row, W.C.l. Hire-purchase finance for the Radio and Electrical trades.

21 Q Assurance Finance Trust Ltd., 21 Q ** *- S Bankers, ** X S Commerce House, 72/86, Oxford Street, London, W.l. Museum 4444 (10 lines). Specialists in Hire Purchase Finance.

220 Armstrong Manufacturing Co., 220 100, King’s Road, Camden Town, N.W.l. ***-*\J Complete range of high-grade Radio Receivers in chassis form are exhibited, ranging from a 6-valve All-Wave Superhetero­ dyne complete with full size Moving Coil Speaker and B.R.V.M.A. valves at £7 10s., to a large 9-valve Multi-wave- band Superheterodyne with push-pull output.

221 The Efficiency Magazine, 221 Kent House, 87, Regent Street, London, W.l. "*"*-*■ The Efficiency Magazine is owned by Mr. Herbert N. Casson. It is the best-known business journal in the British Empire and has four foreign editions. Also publishers of the Casson Business Books. Subjects chiefly dealt with are : Salesman­ ship, Advertising, Staff Training, Management and Manu­ facturing. Special libraries for radio dealers.

222 The Econosign Co., Ltd., 222 92, Victoria Street, London, S.W.l. The Econasign Co., Ltd., 92, Victoria Street, London, S.W.l, are again showing their patent “ Econasign ” Printing Outfits for the production of Showcards, Notices, Price Tickets, etc. Also the “ Econasette ” Titling Outfit for producing screen titles. Amateur Cine Photographers should ask to see this new apparatus. 137 BY APPOINTMENT

THE Mayfair

Window Cleaning Co., Ltd.

OFFICIAL STAND CLEANING CONTRACTORS to this and all important Exhibitions at the

Olympia, Earl’s Court, and the Royal

Agricultural Hall.

SPECIALISTS in all branches of FLOOR POLISHING, VACUUM & GENERAL CLEANING

All work completed by an efficient staff under the supervision of experienced inspectors.

EMPLOYEES FULLY COVERED BY INSURANCE

Head Office: 18, GRANTHAM PLACE, PARK LANE, W.l. Telephone: GROSVENOR 2851 (2 Lines).

And at NOTTINGHAM & LEICESTER. NOTTINGHAM 40886. LEICESTER 58431.

138 y '

TRADE SECTION. Ij

GRAND HALL: GALLERY.

Stand No. Grand Hall, Gallery. Stand No. Memoranda.

XI “The Wireless & Electrical Trader” XI JL JL Proprietors : The Trader Publishing Co., Ltd. Dorset House, Stamford Street, S.E.l. Branch Offices : Birmingham and Manchester.

“THE WIRELESS & ELECTRICAL TRADER.”—The ! pioneer trade journal of the industry. Circulates to 10,000 bona fide traders, keeping them abreast of all developments in the trade, and providing up-to-date news of Radio and Electrical products for resale and service. By subscription, 10s. 6d. a year. Overseas, 15s. 6d. a year. “ THE WIRELESS TRADER ” YEAR BOOK for the Radio i and Electrical Trader. 1938 (14th) Edition ready in Novem­ i ber. Vital trade, technical and buying reference, Trade \ Directory, Quarto Diary, etc. 7s. 6d. post free. To “ Trader ” Subscribers, 4s. 6d. per copy. Overseas, 2s. extra. “ TRADER ” SERVICE SHEETS, AGREEMENT FORMS FOR HIRE PURCHASE, ETC., ETC.

“ The Broadcaster ” T2 Odhams Press Ltd., T2 29, Bedford Street, Strand, London, W.G.2. ! i Published every Saturday, 10s. 6d. yearly, post free, including :—

■' “ Service Engineer ” (8 pages) loosely inset in every issue ; facilities of Service Bureau covering every branch of radio retailing and servicing ; exclusive special supplements, etc. “ Service Man’s Manual ” (four quarterly issues), 5s. yearly, . post free, to “ Broadcaster ” subscribers. “ Broadcaster ” Trade Annual—enquire for details of special terms. “ Part Exchange Allowance Schedule ” and “ Hire-Purchase Schedule,” 6d. each to “ Broadcaster ” subscribers ; “ Practi­ cal ” Electrician’s Pocket Book,” 2s. 6d.; “ Market Survey of Wired Homes,” 3d. “ Electrical Trading ” monthly (7s. 6d. yearly, post free), special rate of 5s. to “ Broadcaster ” subscribers handling domestic electrical appliances. A complete service for radio and electrical dealers. 139 BY APPOINTMENT 9

IE VE FLUID

THE BEST DISINFECTANT AND GERMICIDE

6d., M- AND 1/6 NON-DRIP BOTTLES SAFE — EFFICIENT — ECONOMICAL

THIS EXHIBITION IS DISINFECTED

THROUGHOUT WITH JEYES’ FLUID

JEYES’ ANTISEPTIC DENTAL CREAM IN COLLAPSIBLE TUBES II- EACH

JEYES’ ANTISEPTIC SHAVING CREAM IN COLLAPSIBLE TUBES 11- EACH

JEYES’ PORCELAIN FINISH TOILET BOX VALUE 5/- FREE From your usual Chemist or Store with the purchase of ten 6d. packets of JEYES’ ANTISEPTIC TOILET PAPER

JEYES’ SANITARY COMPOUNDS CO., LTD., 99, Regent Street, London, W.l.

140 F

Stand No. Grand Hale, Gallery. Stand No. Memoranda.

J. J. Eastick & Sons, 118, Bunhill Row, London, E.C.l. In addition to a representative range of well known makes of receivers, speakers, service instruments and radio accessories, etc., we are exhibiting lines of our own manufacture which include short-wave convertors, testing prods, safety switches, and- “ Eelex ” standardised plugs and sockets, lead-in tubes, knife switches, frame aerials, earth bowls, earth tubes, and many other accessories of interest to the wireless enthusiast.

Manufacturers’ Accessories Co. T4(1928) Ltd., T4 85, Great Eastern Street, London, E.G.2.

Radio and Television Sets of all types, Aerials, Masts, Maco Accumulators, Batteries, Earths, Loud Speakers, Chargers, Mains Units, Condensers, Plus-a-Grams, Electric Gramophone Motors, Pick-ups, Resistances, Testing Instruments, Trans­ formers, Wire and Flex, Valves of all makes, Electric Clocks, Electrical Appliances, in fact everything for the Radio and Electrical Trader.

TC Thompson, Diamond A & Butcher, T5 34, Farringdon Road, London, E.C.l. Telephone : Clerkenwell 5492. and at 351, Commercial Road, Portsmouth. Telephone : Portsmouth 73832.

THE QUICK DELIVERY FACTORS. An exhibit intended for the trade only, including the following proprietary lines for the coming season :— PHILIPS, ULTRA, G.E.C., KOLSTER BRANDES, ALBA, BEETHOVEN, R.G.D. Also, for Home Trade and Export, our own manufactured “ NATIONAL BAND ” Gramophones, and an entirely new range of CONVERTOGRAMS of beautiful design, com­ prising the following types, in STANDARD AND DE LUXE FINISHES. Table Models, Cabinet Models for A.C. and Universal Mains and Automatic Record Changer Models, both A.C. and Universal. Also a range of “ NATIONAL BAND ” DRUMS and JAZZ SETS. All London and Provincial Representatives, as well as Technical Assistants will be in attendance. STOCKS OF ALL NEW SEASON’S RADIO AVAILABLE ; prompt despatch and service will again be our big feature this season. 141 Stand No. Grand Hall, Gallery. Stand No. Memoranda. rP< L.E.S. Distributors, Ltd., -1- ^ 15/16, Alfred Place, W.C.l. T6 The Exhibits on this stand are for the Trade only. These will consist of a representative display of Receivers and Radio­ grams by the leading Manufacturers. Dealers will be welcomed, a full staff of Representatives being in attendance.

np7 Flinders (Wholesale) Ltd., T7 ■ 14/20, St. Peters Street, Ipswich. -*■ " Dealers visiting Radiolympia from Eastern Counties will receive a hearty welcome at this stand. Products of leading Receiver Manufacturers will be displayed.

'T'C Horace Dibben Limited, 'T'Q 34, Carlton Crescent, Southampton. ^ We are shewing a complete range of receivers factored by the Company, including Philips, Ultra, G.E.C., K.B., Ever Ready.

R. Cadisch & Sons, T9 5/6, Red Lion Square, London, W.C.l. T9 RADIO RECEIVERS.—Mains and Battery operated, by Ultra, G.E.C., Roister Brandes, R.G.D., Beethoven, Aero­ dyne, Invicta, Ever Ready, Vidor, Alba. RADIOGRAMOPHONES.—-New seasons productions by R.G.D., Ultra, G.E.C., Invicta. CHARGING PLANT.—Westinghouse, Davenset. SERVICE EQUIPMENT.—Valve Testing Units and Oscil­ lators by Radiolab, Avometer, Weston*. PUBLIC ADDRESS EQUIPMENT.—Includes Trix Portable Sound Equipment, Amplifiers, Microphones, Flare and Horn type Speakers. GRAMOPHONE ATTACHMENTS.—Garrard Automatic Record Changers, Radiogram Units, Playing Desks, Gramo­ phone Motors. LOUD SPEAKERS.—Chassis and Cabinet types by Whiteley Electrical, Ltd. COMPONENTS.—Display of Aerial Equipment, Condensers, Pick-ups, Meters, Resistances, Suppressors, Switches. Our Representatives and Salesmen will be on duty throughout the Show. 142 Stand No. Grand Hall, Gallery. Stand No. Memoranda.

HT1A Hobday Brothers Ltd., 21, 23, 25, 27, Great Eastern Street, ^ ^ London, E.G.2, and at Manchester, Sheffield and Wolverhampton. This trade display, in itself comprises an exhibition in miniature, presents in an attractive manner the new Models of Manufac­ turers subscribing to the Fair Trading Agreement. ' Grouped with equal prominence given to each individual display and featuring Radio Gramophones and Consoles as well as i Table Models it enables the Trader to make essential com­ parisons as to the sales value under varying retail conditions in comparative seclusion and complete comfort as there is ample space to move freely between the exhibits. In addition to the London and Home Counties sales staff, Representatives working Northern and Midlands counties will be in attendance to meet trade friends from their terri­ tories so that the visitors anticipated from the North will normally find a familiar face to greet them or can promptly be given information respecting their particular districts including complete details concerning the unique Free Van Delivery Service which is operating in 42 counties from London and Provincial Depots.

HPI 1 J. M. Webber & Go., Ltd., rP1 1 XXX Weblite House, 37/39, Great Eastern Street, London, E.G.2. Telephone : BIShopsgate 1667-8-9. Telegrams : Weblite Finsquare London. A general display of the more popular F.T.A. Receivers and Radiograms, B.V.A. Valves, A.R.B.M. Batteries and Accumu­ lators, Loud Speakers and Electrical Accessories for use with Radio. Our trade friends are at libery to use Stand T11 to meet their own friends. We welcome this opportunity to repeat our invitation to our old friends, as well as new, to visit us to discuss the “ WEBLITE SERVICE.”—DELIVERY BY RETURN—NO WAITING. LARGE STOCKS—PROMPT DELIVER­ IES. ESTABLISHED 1919. THE HOUSE THAT JACK BUILT.

T19 Harris & Russell Ltd., 'T'lO X» 91, Tottenham Court Road, London, W.l, X X^ and 28, Kings Road, Reading, Berks. Telephone, London, Museum 6061-2-3-4. Telephone, Reading, Reading 2076-7. Showing selection of all factored Radio Receivers, Speakers and Components, etc. 143 Memoranda. Stand No. Grand Hall, Gallery. Stand No.

T1 q Selecta Gramophones Ltd., 'T'l ^ “*■ ^ 81, Southwark St., S.E.l. ^ Factors for :—Philips, Alba, Ultra, G.E.C., Beethoven, Decca, Invicta, Aerodyne, Ever Ready, Radio Receivers and Radio­ grams. Leading Stockists of Radio Components. All B.R.V.M.A. Valves in stock, also all types of A.R.B.M. Batteries. Factors for all makes of Records, Makers and Factors of Portable Gramophones. Best delivery service in the Trade. Individual and personal H.P. Scheme available to all dealers. Members of R.W.F. and operators of the A.F.T. & B.C.S. H.P. Plans. Refrigerators and Electrical equipment. I T14 J- Dyson & Co., Ltd., T14 ■ 5/7, Godwin Street, Bradford. JL Comprehensive range of 1937-38 Receivers and Radiograms by Leading Manufacturers. Also range of Loud Speakers and Components. Battery Charging equipment. Allied Electrical and other lines and general requirements of the Radio Dealer.

TIS Lugton & Co., Ltd., TIS 203, Old Street, E.G.l. X Sole Distributors for Ferranti Radio products in London, Beds, Bucks, Herts, Kent, Middlesex, Surrey, Sussex and South Essex. There is displayed a complete range of Ferranti Radio Receivers, Radiograms and Television Receivers. As General Distributors to the Trade and R.W.T.A. Whole­ salers, a representative range of the following products is also exhibited—Alba, Beethoven, Decca, Ever Ready, G.E.C., Invicta, Kolster-Brandes, R.G.D. and Ultra. A special section of this Stand is devoted to Service Equipment for Dealers. There can also be seen ranges of goods produced for the Egyptian market by Messrs. Ferranti, Limited, Britannia Batteries, Ltd., and Garrard Engineering Co., Ltd., to which country Lugton & Co., Ltd., are the Sole Exporters. * T'l A East London Rubber Co., Ltd., T1 fi “** Great Eastern Street, E.C.2, and Branches. *4-^ These well-known Wholesalers will be exhibiting a range of Receivers and Radiograms marketed by Members of the R.W.T.A. A special section is devoted to Test Equipment and Charging Plant. T17 G. Gilbert & Co., Ltd., T1 7 A A f 73/81, Arundel Street, Sheffield. X X f GILBERTS, Sheffield and Branches. THE WISE GUY’S STAND. Of real interest to the Radio Dealer will be displayed :—New lines in Radio Receivers and Radiograms by British Manufac­ turers, also a very comprehensive display of the noted Gilbert small goods will be on view which are always of importance to the wide-awake dealer. The new season’s Gilbert Bulletin will be available free on request at this stand to the trade only. Representatives from the various Branches will be in attendance to greet old and new friends. 144 ■ Stand No. Grand I-Iall, Gallery. Stand No. Memoranda.

T1Q Brown Brothers, Ltd., yiO ^ Great Eastern Street, London, E.G.2, -*■ and Branches. Representative range of Radio Receivers and Radiograms of all leading makes. Special display of Radio Service equipment, with technical staff available for demonstration. Full range of Radio Components, Accumulators, Interference E Devices, Loud Speakers, etc. by prominent makers. I Representative range of Battery Charging Plant, with technical 1 staff available for advice. A full technical and sales staff will be available for dealers, for the selection of stock and for advice on any points that may arise.

T1 Q Houghtons The Wholesalers HP 1 Q (ENSIGN LIMITED), 3- ±. S 88-89, High ITolborn, London, W.C.l ; and at 76-78, York Street, Glasgow; 3, Freeman Street, Moor Street, Birmingham; 18-19, Hill’s Terrace, Cardiff; 38a, Queen Street, Belfast. TRADE ONLY. As distributors for all the principal manufac­ turers Houghtons stand carries a comprehensive selection of the season’s best sellers, including Philips, G.E.C., Ultra, Roister Brandes, Decca, Every Ready, Invicta, W.B., Alba, R.G.D., Beethoven, Burndept, and Aerodyne. It is a con­ venient meeting place for dealers, where only a single order is needed to secure all requirements—with a consequent saving in time, trouble and expense. Houghtons provide an experienced, intelligent and complete service for their customers. nTOO A. J. Dew & Go., Ltd., T90 32/34, Rathbonc Place, W.l. A L*\J Individual displays of new season’s Receivers, Radiograms and Television Apparatus, displayed to facilitate inspection by the Radio Retailer. Side by side comparisons can be made of each manufacturer’s range, or of individual Instruments. A special display of servicing equipment for the Service Engineer including Meters, Valve Testers, Oscillators, Battery Chargers, small Service Tools, etc. Portable Receivers, Extension Speakers, Components and Accessories are comprehensively covered in such manner as to assist easy inspection.

Ol f\ Hillman Brothers, Ltd., 21 f\ 123/5, Albion Street, Leeds, 1. ^XVJ Telephone: Leeds 29574 (3 lines). 30/32, West Bar, Sheffield, 3. Telephone: Sheffield 20788. The Sound Service" Factors for Alba, Bumdept, Decca, Ever-Rcady, G.E.C., K.B., Philips, R.G.D., Ultra and Vidor for Yorks., Notts., Lines, and Derby invite old and new dealer friends to use Hillman’s Stand as their rendezvous and base during their Olympia visit. Valve Stockists’ scheme of special interest to all Dealers. 145 SPECIAL EXHIBITS.

THE RADIOLY MPIA THEATRE.

National Hall.

Memoranda. << ING up the curtain,” and at those words an expectant public will be allowed to share in a unique variety show.

It will be staged in a theatre specially built for it—the only show to have its own theatre. It will conform to all the con­ ventions of the theatre—and yet break them. It will attract a huge crowd, thrice daily, which will be unlike any audience attracted by any other theatre. Into the building of the theatre will have gone months' of work and planning. Three weeks ago where thousands now sit in terraced tiers, their eyes and minds fixed in a focused con- i centration of fascinated interest, on a vast stage filled with famous performers—three weeks ago that space was a flat floor.

In the meantime a theatre that conforms to every L.C.C. requirement imposed on all West End theatres has been erected. A stage, wider than that of most West End theatres, has been built and equipped with a lighting system with which only the most modern theatres of New York and Berlin can compare or compete. Special floors have been laid and nearly 3,000 new seats screwed into position. Promenades accommodating another 1,500 have been provided.

In all physical respects the Radiolympia theatre show will conform to stage traditions ; they will be broken in other ways. Whoever heard of the star of a vaudeville show not being a comedian, a crooner, or a dance-band, but being the composer of serious music ? Whoever heard of a vaudeville show not having a dancing troupe and chorus girls ? Whoever heard of a vaudeville show having the same stage setting for the whole of its first half? In the big ensemble scenes there will be nearly 200 people on the stage. They will wear the costumes of every radio country in the world. Such popular stations as “ Radio Roma ” and “ Deutschlandsender ” will be portrayed. Why ? Because this year’s Radiolympia has a central thematic treatment, and the theme is “ All-World Listening.” “ Radio Round the World ” will be demonstrated in the theatre and in the exhibition. The ever-increasing popularity 146 National Hall. Memoranda.

THE RADIOLYMPIA THEATRE—continued.

of all-wave sets has proved the internationalism of radio and implemented the famous B.B.C. motto “ Nation shall speak peace unto nation.” All aspects of this year’s Radiolympia will combine and conspire to prove how, with radio, everyone can eavesdrop at the keyhole of the world.

TIMES OF PERFORMANCES AND PRICES OF ADMISSION : There will be three performances daily in the Theatre, at 3, 6 and 8 p.m. Admission will be by ticket obtainable in the Radiolympia Theatre Booking Office, situated between the Grand and National Halls, on the Ground Floor. Prices, including tax, 5/9, 3/6, 2/6, 1/3, and 6d. The prices, including tax, at the Matinee Performances on Mondays, Tuesdays and Fridays, will be 3/6, 2/6, 1/3 and 6d.

ARTISTES IN THE PERFORMANCES. The Programme in the Radiolympia Theatre will be varied three times during the course of the show. The artistes appearing are as follows :—

August 25th to August 28th : Paula Green ; Vine, More and Nevard ; Two Leslies ; Beryl Orde ; Sandy Powell and Company ; Royal Master Singers ; Dagenham Girl Pipers ; Bertha Willmot; Donald Thorne and Harry Farmer ; Haver and Lee ; Eric Coates and Orchestra, Jan Van Der Gucht (Vocalist); Sutherland Felce ; Bobby Howell and Orchestra.

August 30th to September lsr : Paula Green ; Stanford and McNaughton ; Phyllis Robins ; Flotsam and Jetsam ; Murray and Mooney ; Royal Master Singers ; Dagenham Girl Pipers ; Bennett and Williams ; Peggy Cochrane; Revnell and West; Louis Levy and Orchestra ; Sutherland Felce; Donald Thorne and Harry Farmer ; Bobby Howell and Orchestra.

September 2nd to September 4th : Paula Green ; Rupert Hazell and Elsie Day ; Mamie Souter ; Three Herons ; Forsythe, Seamon and Farrell; Royal Master Singers ; Dagenham Girl Pipers ; Payne and Hilliard ; Navarre; Leonard Henry; Louis Levy and Orchestra; Sutherland Felce ; Donald Thorne and Harry Farmer ; Bobby Howell and Orchestra. 147 G TELEVISION DEMONSTRATIONS. National Hall.

AST year, the National Radio Exhibition was held before Memoranda. the regular B.B.C. service of television broadcasts from L Alexandra Palace was commenced ; nevertheless, with the co-operation of the B.B.C., who sent out experimental trans­ missions during the period of the Exhibition, the Radio Manu­ facturers’ Association was able to include in the exhibition a demonstration of television reception, the pictures then seen being as close an approximation as possible to what the public might expect to secure on a commercial television receiving set when the television service was in operation.

To-day, the B.B.C. have had many months of experience in television transmission, and the manufacturers have taken the fullest advantage of these transmissions to progress the develop­ ment of television receivers. So, in this year’s exhibition, there is included, in the National Hall, a section in which demon­ strations will be given of the reception of television on receivers suitable for use in the ordinary home, and displayed and avail­ able for purchase on the exhibitors’ stands in the Grand Hall.

The television demonstration section consists of fourteen rooms, in which individual manufacturers will demonstrate, on domestic type receivers, the reception of television trans­ missions actually broadcast from Alexandra Palace, together with the accompanying sound.

In order that as large a number as possible may be able to witness the demonstration, the B.B.C. have arranged special transmission times for the Exhibition period. Nine transmissions will be given by the B.B.C., and received daily in each of the fourteen demonstration rooms.

The times of the demonstrations are as follows :— 11.30 a.m. ; 11.50 a.m. ; 12.10 p.m. ; 4.0 p.m. ; 4.20 p.m. ; 4.40 p.m. ; 9.0 p.m. ; 9.20 p.m. ; 9.40 p.m. The programme at the morning sessions will consist of transmissions of the recently made B.B.C. television film, comprising the most successful items televised during the first six months of the service.

It is understood that a feature of the afternoon programmes, which will consist mostly of outdoor broadcasts, will be a tele­ vision tour of the London Zoo. The B.B.C. Mobile Television Unit will be stationed near Pets’ Corner, so that visitors to Radiolympia may be able to watch the chimpanzees at their tea-party, and children riding the llama and the pony. It is also hoped to televise the feeding of the sea-lions, and other amusing and interesting episodes in the daily routine of the Zoo.

In the evening programmes, a number of carefully contrasted items will be transmitted, but it will be too dark at that time . to televise any outdoor events. us National Hall. Memoranda. TELEVISION DEMONSTRATIONS—Continued. Admission to the demonstration rooms is free, by means of a ticket obtainable at the Box Office at the entrance to the Tele­ vision Demonstration Section. Each ticket will admit only to the particular Demonstration Room indicated, and at the time stated on it. The ticket must be given up at the entrance to the Demonstration Room.

The manufacturers participating in the Television Demon­ strations are as follows :— 4 Room No.

Baird Television, Ltd. 8 i E. K. Cole, Ltd...... 3 A. C. Cossor, Ltd. ... 2 i Edison Swan Electric Co., Ltd. 7 Ferranti, Ltd...... 9 General Electric Co., Ltd...... 10 Halcyon Radio, Ltd...... 13 His Master’s Voice 14 Kolster-Brandes, Ltd...... 11 Marconiphone Co., Ltd...... 5 Philips Lamps, Ltd...... 4 Pye, Ltd...... 6 Radio Gramophone Development Co., Ltd. 1 Ultra Electric, Ltd...... 12

\

UD

I OFFICIAL CONTRACTORS TO THE

R-M-A BROOKS & WHITE

Electrical Engineers

10 Maclise Road, West Kensington,W.I4

AND spffd FFFICTFN C!T 150 RADI OLYMPIA RADIO MUSEUM. Grand Hall, Gallery, Stand 212. Memoranda. ; N the East End of the Gallery will be found a most interest­ i ing exhibit; it is the nucleus of a Radio Museum. Visitors to it will be able to claim being present at the inception of what may become an institution of international importance. Backgrounding the 15 years of British broadcasting is a i century of radio history covering what can be called the Faraday-Fleming period of scientific discovery. This embraces the contributions made by Edison, Hertz, Hughes and Marconi to ■ the development of radio. The second half of the past century ; is rich in the adventure and romance of radio and there is a danger of myth and legend taking the place of history. It is, therefore, a matter of importance that the relics of the past i should be preserved and made available to public scrutiny. : To that end a “ Museum ” has been commenced at Radiolympia this year—a feature that will grow and expand as time adds ! value to achievements of the past. A visit to the “ Museum ” in the Gallery will not only be of interest and informative ; it may easily become an event in the life of the visitor. In years to come, when the National Radio Museum is as prominent a feature of London life as the Science Museum and the War Museum, today’s visitor will proudly boast of being present at its birth. There can be seen items of historic value. One of the chief collections—appropriately enough in this year of mourning— is devoted to museum pieces of Marconi’s work. Some of his experimental equipment, photographs of his earliest radio adventures, apparatus that was used in events that have now assumed historic proportions—these and much more are on view. In addition will be found museum pieces loaned by the fathers of British broadcasting—those amateur experimentalists connected with the first Wireless Club, formed before the in­ ception of the B.B.C. To this first collection men who have grown up with radio have contributed. Relics of the pre-B.B.C. era and other interesting items from early B.B.C. days help to make this “Museum” one of the most valuable adjuncts to this very varied Radiolympia. To all those who have loaned Museum pieces, the 'Organisers tender appreciative thanks. Visitors can express their own appreciation by visiting the “ Museum,” and taking an intelligent interest in the development of this magic, called broadcasting, which gives them so many happy hours daily throughout the years.

r #vi. 151 RIST’S WIRES & GABLES

LIMITED 3 D WAVENEY WORKS, LOWESTOFT. I The Products exhibited on this stand A will be a representative range of P samples of Wires, Flexibles, and Conductors for Radio purposes. " Super-Range " Aerials, 7/25

STAND Aerials, Twin Flat Extension Cord 0 No. ISO for Loudspeakers, etc., Art Silk or Glace cotton. Screened Tubing, M Wireless Lead-in-Wires, Wireless I Flexibles, Screened Flexible Con­ ductors, Pushback Connecting Wires, Mains Leads, Wiring Assem­ blies, etc., made to specifications and Drawings.

SHELFORD PLACE, CHURCH ST. GRAND HALL GALLERY LONDON, N.I6 STAND NO. 159.

ACCRINGTON

Accrington Brick and Machinery Access by Road, Rail and Canal Cotton Weaving and Spinning-Calico Printing Coal, Coke and Gas from Pithead Engineering-Agriculture-Domestic-Textile Electricity, Cheap Light and Power Soap-Paint-Paper Manufactures Sites for Works at £5 per acre p.a.

Abundant Soft Water Amenities Already Provided Cheap Factory Rentals—£150p.a.—54, OOOsq.ft. Commercially Attractive Employees—Skilled-Male and Female Existing Businesses Extending Shopping Centre-" Easy” Rates & Assessments Scenery of Ribble Valley for Leisure

PLANT your WORKS where you CAN WORK your PLANT

Apply for details to Hon. Sec., Industrial Development Committee, ACCRINGTON ENGLAND

152

'I :

GENERAL POST OFFICE EXHIBIT. RADIO INTERFERENCE BUREAU.

Grand Hall, Ground Floor, Stand 98. Memoranda. T seems only yesterday that the great invention wireless was ' born, yet it is now such a sturdy child that the vast majority i I of the public can rightly expect polished broadcast recep­ tion. Unfortunately, the trouble of interference is still prevalent, I and this exhibit has been designed to demonstrate the progress made in the suppression of interference caused by electrical apparatus. Since the introduction of regular television transmissions . on ultra short waves from the Alexandra Palace, the Post Office has extended its Radio Interference Service to cover television. ii It is appropriate that the exhibit should show something of what is being done for television viewers. i - : DEMONSTRATION OF INTERFERENCE WITH TELEVISION. This demonstration is the main feature of the Stand and is intended to show what forms of interference television may experience. The interference caused by an ultra short wave therapy apparatus (such as is used in many hospitals) will be shown on the screen of a standard television receiver. It will be demonstrated how this interference is suppressed by enclosing the therapy apparatus in a screened room. The other source of interference with television is the ignition system of a motor vehicle. This will also be demonstrated, together with the method of suppression.

MODEL WALL OF SCREENED ROOM. The model is displayed showing several ways in which a room / may be screened in order that electrical diathermy therapy or “ violet ray ” apparatus may be used without causing inter­ ference to nearby broadcast listeners or television viewers.

RADIO INTERFERENCE ENQUIRY BUREAU. As in previous years, there is a large bureau staffed by Post Office Radio Interference Enquiry Officers. These men are familiar with all of the interference problems which confront the ordinary listeners, and advice and assistance is given free. Complaints of interference made at this bureau will be dealt with by the Post Office Radio Interference Service. No fewer than 45,000 complaints were received from all over the country and dealt with by the Post Office during the past year. Enough has been said to show that for its part the Post Office ,is continuing and expanding its efforts to assist those listeners who are troubled with interference. The demonstrations will conclusively prove that interference can be cured, and the ordinary listener can assist the Post Office by asking for advice, for which purpose the demonstrators on the Stand are at their service. .

153 D A hlA TIM EC FULL BBC PROGRAMMES A WEEK *}D KAUiU l lm to IN ADVANCE. EVERY FRIDAY &

— ;; & »illl ll 11 / 1II,? a itty

WORLD-RADIO SS 2D

*» I N

.11 B Sc

THE BEST BROADCAST TALKS, THE LISTENER ILLUSTRATED. EVERY WEDNESDAY 3- d

i/f/gl* r /a/s //f I P5S 7M

fisc v.; ii

'Agents A r / © wr «bookjr~-- *** ^£v«vvvH£^

J54 ! f A DESCRIPTION OF ■ ; THE SPEECH-AMPLIFYING EQUIPMENT FOR THE THEATRE I AND FOR PROGRAMME DIFFUSION TO EXHIBITORS’ STANDS.

.Memoranda. S in the past four years, there is again a Theatre in the 1 Olympia building, to which the public will be admitted A and in which performances will be given by broadcasting artists during the whole period of the Exhibition. Some of these performances will be radiated from the B.B.C. transmitters as part of the normal programme, just in the same way as other Outside Broadcasts, and the B.B.C. is responsible for the technical equipment required. The B.B.C. is also responsible for the apparatus which supplies programmes of music and speech to exhibitors for demonstration purposes. These two features involve a con­ siderable amount of equipment which has been designed and : I installed by the B.B.C. J The apparatus is in two distinct sections :— (1) Apparatus in connection with the Theatre, which is j located on and adjacent to the stage, and consists, in the main, of a somewhat elaborate “ Outside Broadcast ” equipment. f (2) Apparatus on the first floor of the Grand Hall, which is concerned purely with supplying programmes to the loudspeaker points on the Exhibition stands. l Although the equipment described above will not be on general view, arrangements may be possible for those specially ! interested to view the equipment by application to the B.B.C. Engineers on duty. These inspections can, of course, only be : arranged when there are staff and time available to show visitors round.

(1) THEATRE EQUIPMENT. The Theatre equipment is divided into two portions, one of which is used solely for Outside Broadcasts while the other feeds the Public Address loudspeakers in the Theatre itself. On the stage are the microphones which are of the ribbon type and are arranged in duplicate, one set being used for the Outside Broadcast programmes and the other for supplying the Public Address system in the Theatre. The outputs from the ; latter are taken to a cubicle situated in the gallery of the Theatre where the outputs from the various microphones arc mixed by means of potentiometers. Any number of microphones up to eight can be handled on the mixing desk installed. From this cubicle the programme is fed to a control room situated adjacent to the stage, where it is passed through a 3-stage resistance-coupled amplifier, termed an “ A ” amplifer. A 155 SPEECH-AMPLIFYING EQUIPMENT—Continued. spare “ A ” amplifier is provided which can be brought into Memoranda. use immediately if required. The “ A ” amplifier has two independent output stages, one feeding the monitoring circuits while the other supplies a mains-operated power amplifier which feeds the Public Address loudspeakers via a main volume control situated in the cubicle. The cubicle is unenclosed to enable both mixing and the control of volume to be judged on the Theatre loudspeakers. The power amplifier employs two stages of triodc amplification with resistance-capacity coupling, feeding into a parallel push-pull stage consisting of six large-power triodes each having an anode dissipation of 25 watts. Two separate output transformers are provided which permit the use of all six or only two of the output valves, according to requirements, the undistorted L.F. output in the former case being of the order of 25 watts. There are separate H.T. supplies for the output stage and for the earlier stages, and the anode current of each output valve can be read on a meter by throwing a key. Five large horn-type moving coil loudspeakers are installed in the Theatre. The two “ A ” amplifiers, a “ programme meter ” amplifier and their associated jackfield are mounted on a rack 5 feet in height. A second rack carries all auxiliary equipment associated with the microphone circuits. The “ programme meter,” calibrated in decibels, indicates the instantaneous level of the speech currents delivered to the outgoing, lines. The apparatus used when the Theatre programmes are being broadcast is situated in a sound-proof cubicle at the side of the stage and consists of standard Outside Broadcast equipment comprising a microphone mixer, a four-stage resistance-coupled amplifier and. a monitoring loudspeaker which is supplied from a separate amplifier. A spare four-stage amplifier is provided, together with a change-over switch which enables it to be brought into use immediately if required. The output from the main amplifier is fed via Post Office lines to the Control Room at Broadcasting House and thus the programme in the Radiolympia Theatre can be distributed to the various transminers. The power supply for all the equipment described above other than the Public Address amplifier is derived entirely from batteries, which are charged through rectifiers from the mains supply.

(2) EXHIBITION DIFFUSION EQUIPMENT. The programmes for diffusion to the exhibitors’ stands are j supplied by equipment which is entirely separate from that described above, and linked with the Control Room only by the j lines already mentioned, to enable programmes originating in j Broadcasting House or at the Radiolympia Theatre to be taken j when desired. 15G SPEECH-AMPLIFYING EQUIPMENT—Continued.

To a large extent the programme matter for the stands is Memoranda. derived from gramophone records, which are reproduced from a studio in Olympia. The facilities thus provided are also used for giving out such public announcements as may be required throughout the day. In the studio is a desk containing two gramophone units and a microphone unit with a 3-way switch for connecting any of these to the amplifier chain as desired. The actual switching is effected by remote control relays in the Power Amplifier Room itself. These relays connect the studio output to a 3-stage amplifier consisting of two high-gain triodes followed by a power triode, all indirectly heated. A potentiometer is included at the grid of the second stage, this being the only volume control in the chain. This amplifier is duplicated and the standby amplifier can be brought into circuit in the event of a breakdown of the first, by means of a simple plug and jack arrangement at the input and output. These amplifiers are mounted together on a rack, and their complete power supply and smoothing equipment is mounted on another similar rack, the power being derived from the A.C. mains. Between the two racks is a small control desk, on which is a meter giving visual indication of the strength of the signal supplied to the lines feeding the various stands. The . power supply units in the second rack are also in duplicate, and there is further provided in this room an emergency gramophone and microphone desk.

THE POWER AMPLIFIER. It is now necessary to develop sufficient power to feed the large number of loudspeakers on the exhibitors’ stands, and for this purpose the power amplifier has been designed to give an undistorted output of 400 watts. The whole amplifier is mounted in a metal-framed unit. The input from the 3-stage ’ «. speech amplifier already referred to is applied via a push-pull ■ transformer to the grids of the first stage. The valves used here are triodes, having an anode dissipation of 30 watts each and grid bias of 120 volts. These are resistance-capacity coupled to the output stage which is arranged as two separate push-pull pairs, each with its own output transformer. Each of the output triodes has an anode dissipation of 700 watts, and the total undistorted output obtainable from the four is 400 watts approximately. Meters are included in all anode circuits and a level-indicating meter connected in series with that on the control desk is fitted on the instrument panel. In the lower part of the amplifier unit is housed the grid-bias supply apparatus for both stages. The programme is distributed to the various loudspeaker points via a number of main feeders, half the feeders being 167 H SPEECH-AMPLIFYING EQVIPMEST-Continucd.

supplied from each output transformer. Each feeder is con­ Memoranda. trolled by a switch, and facilities are provided for determining the power taken by each individual feeder. In the event of an accidental short-circuit being produced across any one feeder, the faulty line can immediately be located and put out of circuit until the fault has been remedied, so that the other lines are not disturbed. As an additional precaution each individual loudspeaker point has a protective! 2,000 ,ohm resistance in

series with it. ln.1r

POWER AMPLIFIER H.T. AND L.T. SUPPLY.

The power supply equipment is housed in a separate unit of the same dimensions as the amplifier unit. A transformer supplies A.C. at 18 volts for the output stage filaments, but the filament supply to the first stage is D.C., obtained from metal rectifiers and is adequately smoothed, it being important to keep the hum in this stage at a very low level. The H.T. supply is obtained from a pair of half-wave mercury-vapour rectifiers arranged as a full-wave rectifier capable of supplying 1 ampere at 3,000 volts. When the main switch on the front of the unit is closed, the A.C. mains are connected to the transformers supplying the filaments of both stages, the grid-bias rectifier, and the transformer for heating the filaments of the mercury vapour rectifiers. It is essential that these latter filaments should be given two or three minutes to heat up and that negative bias should be applied to the grids before the main H.T. is switched on ; there is, therefore, an additional switch for connecting the A.C. mains to the transformer feeding the mercury vapour rectifier anodes. This switch is operated by a relay in a secondary circuit in which are included contacts which are closed by means of doors at the back of the power supply unit and of the power amplifier unit, so that is is impossible to switch on the H.T. when any one of these doors is open.

The final operation of switching on is the closing of a switch in a secondary circuit, located on the front of the unit. In series with the primary winding of the H.T. transformer are two resistors, one graded in steps and the other continuously variable, in order that the H.T. voltage may be brought to its full value gradually, thus avoiding a possible dangerous surge which might damage valves or smoothing condensers. The smoothing provided for the H.T. supply consists of two con­ densers, one of 6 mfd. and one of 8 mfd., and a 9 henry choke. This unit includes a certain amount of heavy apparatus, and it is not surprising to find that the complete power supply unit weighs about 5 cwt. A standby power supply unit is provided.

168 CLASSIFIED DIRECTORY OF EXHIBITS.

STAND NO. STAND NO. Accumulators. Battery Chargers. (See Accumulator Britannia Batteries, Ltd. ... 83 Charging Equipment.) i Chloride Electrical Storage Co., Ltd. 32 Edison Swan Electric Co., Ltd. 57 Cabinets. Ever Ready Radio, Ltd. ... 58 Fuller Accumulator Co. (1926), Ltd. 100 D. M. Davies Woodwork ... 16 Siemens Electric Lamps & Supplies De la Rue & Co., Ltd., Thos. 6 Ltd...... 31 Eddystone Radio 23 Sterling Batteries, Ltd. 5 Stratton & Co., Ltd...... 23 Texaloom Radio, Ltd...... 15 Accumulator Charging Equipment. i All-Power Transformers, Ltd. ... 209 Cathode Ray Oscillographs. i I Crypton Equipment, Ltd. ... 202 Cossor, Ltd., A. C. 61, 163 Edison Swan Electric Co., Ltd. 57 Milliard Wireless Service Co., Ltd. ... 161 Heayberd & Co., F. C. 25 : Milnes Radio Co., Ltd. 88 Partridge Wilson & Co., Ltd. 29 Cathode Ray Tubes. Sound Sales, Ltd...... 89 Telsen Electric Co. (1935), Ltd. ... 90 Baird Television, Ltd...... 87 Westinghouse Brake & Signal Co., Ltd. 77 Cossor, Ltd., A. C...... 61, 163 Edison Swan Electric Co., Ltd ... 57 General Electric Co., Ltd. 54,62 Aerials and Aerial Equipment. Milliard Wireless Service Co., Ltd. ... 72 i: Aerialite, Ltd...... 28 Belling & Lee, Ltd...... 42 Ceramics. British Pix Co., Ltd...... 211 Bulgin & Co., Ltd., A. F. 1 Steatite & Porcelain Products, Ltd. ... 152 Eastick & Sons, J. J...... T3 His Master’s Voice ...... 66,76 New London Electron Works, Ltd. ... 80 Chassis. Radio Gramophone Development Co., Armstrong Mfg. Co...... 220 Ltd...... 67 British Television Supplies, Ltd. ... 47 Rists’ Wires & Cables, Ltd...... 159 Harries Thermionics, Ltd. 3 Telsen Electric Co. (1935), Ltd. ... 90 Haynes Radio, Ltd...... 11

Amplifiers. Chassis Mounting Strips. Ardente (R. H. Dent, Ltd.) ... 2 British Mechanical Productions, Ltd.... 94 British Television Supplies, Ltd. . 47 Cossor, Ltd., A. C...... 61,163 Film Industries, Ltd. ... 4 Chokes. Gambrell Electrical Equipment Co., All-Power Transformers, Ltd. ... 209 Ltd...... 14 Belling & Lee, Ltd...... Shaftesbury Microphones, Ltd. 92 ... 42 89 Bulgin & Co., Ltd., A. F. 1 Sound Sales, Ltd...... Eddystone Radio ...... 23 Tannoy Products (Guy R. Fountain, .. 86 Haynes Radio, Ltd...... 11 Ltd.)...... Heayberd & Co., F. C. 25 Whiteley Electrical Radio Co., Ltd. ... 75 Plessey Co., Ltd...... 22 Sound Sales, Ltd...... 89 Stratton & Co., Ltd...... 23 Associations. Telsen Electric Co. (1935), Ltd. 90 Radio Society of Great Britain ... 214 Varley (Oliver Pell Control, Ltd.) 99 Wireless Retailers’ Association of Great Wingrove & Rogers, Ltd. ... 44 Britain & N. Ireland ... 203 Coils, Tuners, etc. Batteries. Bulgin & Co., Ltd., A. F. 1 Aerialite, Ltd...... 28 Eddystone Radio ... 23 Britannia Batteries, Ltd...... 83 Sound Sales, Ltd. ... 89 British G. W. Z. Battery Co., Ltd. ... 82 Stratton & Co., Ltd...... 23 Chloride Electrical Storage Co., Ltd. 32 Telsen Electric Co. (1935), Ltd. 90 Ever Ready Radio, Ltd. ... 58 Varley (Oliver Pell Control, Ltd.) ... 99 Fuller Accumulator Co. (1926), Ltd. 100 Wingrove & Rogers, Ltd. ... 44 General Electric Co., Ltd. 54,62 Lissen, Ltd...... 73 Siemens Electric Lamps & Supphes, Coil Winding. Ltd. ... 31 Sterling Batteries, Ltd. 5 Automatic Coil Winder & Electrical Vidor, Ltd. ... 33 Equipment Co., Ltd. 30,166 169 (Continued on next page.) DIRECTORY OF EXHIBITS con tinued. CLASSIFIED

stand no. stand: ;no. Eliminators and Mains Equipment. Condensers, Fixed and Variable. Dubilier Condenser Co. (1925), Ltd. ?! ! All-Power Transformers, Ltd. ... 209 Eddystone Radio ...... 23 Cole, Ltd., E. K. ... 69 Hunt, Ltd., A. H. ••••** . 155 Heaybcrd & Co., F. C. 25 Jackson Bros. (London), Ltd. ... . 93 Milnes Radio Co., Ltd...... 88 Norman Rose (Electrical), Ltd. 207 Regentone Products, Ltd. 97 Plessey Co., Ltd...... 22 Telsen Electric Co. (1935), Ltd. ... 90 Stratton & Co., Ltd. ... • •• 23 38 Telegraph Condenser Co., Ltd. Eyelets, Tags, etc. Telsen Electric Co. (1935), Ltd. 90 Wingrove & Rogers, Ltd. ... 44 Bifurcated & Tubular Rivet Co., Ltd. 151 Tucker Eyelet Co., Ltd., Geo. ... 102

Converters, D.C./A.C. Filters. Philips Lamps, Ltd...... 68 Belling & Lee, Ltd. ... 42 Regentone Products, Ltd. ... 97 Finance Companies. Assurance Finance Trust, Ltd. ... 219 Cones for Loud Speakers. Bowmakcr, Ltd...... 217 Bridger & Co., Ltd., R. O. ... 150 Mercantile Credit Co., Ltd...... 215 Olds Discount Co., Ltd. .. 218

Connectors and Cords. Fuses and Fuse Holders. Belling & Lee, Ltd...... 42 Belling & Lee, Ltd. ... 42 British Mechanical Productions, Ltd. 94 Bulgin & Co., Ltd., A. F. 1 Bulgin & Co., Ltd., A. F...... 1 Henley’s Telegraph Works Co., Ltd., W. T...... 20 Gramophone Motors and Chassis. New London Electron Works, Ltd. ... 80 Collaro, Ltd...... 101 Rists’ Wires & Cables, Ltd...... 159 Cosmocord, Ltd. ... 48 Garrard Engg. & Mfg. Co., Ltd. ... 37

Control Units. Gramophone Pick-ups and Arms. Ardente (R. H. Dent, Ltd.) ... 2 Belling & Lee, Ltd. ... 42 Collaro, Ltd...... 101 Cosmocord, Ltd...... 48 Coupling Units & Devices. Edison Swan Electric Co., Ltd. 57 Garrard Engg. & Mfg. Co., Ltd. ... 37 Bulgin & Co., Ltd., A. F. 1 His Master’s Voice ...... 66,76 Telsen Electric Co. (1935), Ltd. ... 90 Deaf Aids. Headphones. Ardente (R. H. Dent, Ltd.) ... 2 Edison Swan Electric Co., Ltd. ... 57

Dials, Knobs, etc. H.T. Supply Units. All-Power Transformers, Ltd...... 209 British Metal Engraving Co., Ltd. ... 158 Cole, Ltd., E. K...... 69 Eddystone Radio .. 23 Heayberd & Co., F. C. ... 25 Jackson Bros. (London), Ltd. 93 Milnes Radio Co., Ltd. ... 88 May & Baker, Ltd. 157 Regentone Products, Ltd. Stratton & Co., Ltd...... 23 Telsen Electric Co. (1925), Ltd. Telsen Electric Co. (1935), Ltd. ... 90 ::: g Wright & Weaire, Ltd. ... 165 Insulating Materials. De la Rue & Co., Ltd., Thos. 6 Diaphragms for Loud Speakers, Mica & Micanite Supplies, Ltd. ... 154 Microphones, etc. ... 150 Bridger & Co., Ltd., R. O. Interference Suppressors. Belling & Lee, Ltd. ... 42 Sound Sales, Ltd. ... 89 Drives for Condensers, etc. Jackson Bros. (London), Ltd ... 93 Lightning Arresters. ... 22 Plessey Co* Ltd. British Pix Co., Ltd. ... Wingrove & Rogers, Ltd. ... 44 ... 211 160 (Continued on next page.j i

i

CLASSIFIED DIRECTORY OF EXHIBITS—continued.

STAND NO. STAND NO. Loud Speakers. Mouldings and Moulding Materials. Ardentc (R. H. Dent, Ltd.) ... 2 De la Rue & Co., Ltd., Thos. 6 Benjamin Electric, Ltd. 17 Mica & Micanite Supplies, Ltd. 154 British Rola Co., Ltd. 41 Whiteley Electrical Radio Co., Ltd. ... 75 British Television Supplies, Ltd 47 Celestion, Ltd...... 26 Edison Swan Electric Co., Ltd. 57 Nameplates. Film Industries, Ltd...... 4 Goodmans Industries, Ltd. 43 British Metal Engraving Co., Ltd. ... 158 Haynes Radio, Ltd...... f. ,.. 11 • His Master’s Voice ...... 66, 76 Philips Lamps, Ltd...... 68 Plessey Co., Ltd...... 22 Oscillators. Pye, Ltd...... 60 Radio Gramophone Development Co. Automatic Coil Winder & Electrical Ltd...... 67 Equipment Co., Ltd. 30, 166 Reslo (Sound Equipment), Ltd. 24 Cossor, Ltd., A. C...... 61, 163 Shaftesbury Microphones, Ltd. 92 Everett, Edgcumbe & Co., Ltd. ... 164 Sound Sales, Ltd...... 89 Milliard Wireless Service Co., Ltd. ... 161 Weston Electrical Instrument Co., Ltd. 167 Tannoy Products (Guy R. Fountain ■ Ltd.)...... 86 Wright & Weaire, Ltd. ... 165 .! Telsen Electric Co. (1935), Ltd. 90 Ultra Electric, Ltd...... 63 Whiteley Electrical Radio Co., Ltd. ... 75 Photo-Electric Cells. Baird Television, Ltd. ... * ... 87 Loud Speaker Units and Chassis. Benjamin Electric, Ltd. ... 17 British Rola Co., Ltd...... 41 Pianos. Celestion, Ltd...... 26 Goodmans Industries, Ltd. 43 Barratt & Robinson, Ltd. ... 201 Edison Swan Electric Co., Ltd 57 Eavestaff & Sons, Ltd., W. G. ... 204 Plessey Co., Ltd. 22 Tannoy Products (Guy R. Fountain, Ltd.) ... . 86 Plugs and Sockets. Whiteley Electrical Radio Co., Ltd. ... 75 Belling & Lee, Ltd. ... 42 British Mechanical Productions, Ltd. 94 Bulgin & Co., Ltd., A. F. 1 Metal Pressings, etc. Eastick & Sons, J. J...... T3 Davis & Timmins, Ltd. ... 213 Goodmans Industries, Ltd. ... 43 Potentiometers. (Sec Volume Controls). Meters and Measuring Instruments. Automatic Coil Winder & Electrical Public Address Equipment. Equipment Co., Ltd. 30, 166 2 ... 164 Ardente (R. H. Dent, Ltd.) ... Everett, Edgcumbe & Co., Ltd British Television Supplies, Ltd. 47 Ferranti, Ltd...... 21 26 Milliard Wireless Service Co., Ltd. ... 161 Celestion, Ltd...... Film Industries, Ltd...... 4 Partridge-Wilson & Co., Ltd. .. 29 54,62 .. 162 General Electric Co., Ltd. Radiometers, Ltd. Goodmans Industries, Ltd. ... 43 Salford Electrical Instruments, Ltd. ... 168 24 Telsen Electric Co. (1935), Ltd. .. 90 Reslo (Sound Equipment), Ltd. Shaftesbury Microphones, Ltd. . 92 Weston Electrical Instrument Co., Ltd. 167 89 Wright & Weaire, Ltd. ... 165 Sound Sales, Ltd...... Tannoy Products (Guy R. Fountain, Ltd.)...... 86 Microphones & Transmitting Apparatus. Whiteley Electrical Radio Co., Ltd. ... 75 Ardente (R. H. Dent, Ltd.) ... 2 Film Industries, Ltd...... 4 Radio Gramophones. General Electric Co., Ltd. 62 Haynes Radio, Ltd...... 11 Ace Radio, Ltd...... 103 Reslo (Sound Equipment), Ltd. 24 Balcombe, Ltd., A. J...... 55 Shaftesbury Microphones, Ltd. 92 Beethoven Radio, Ltd. 34 Sound Sales, Ltd.' .. 89 British Belmont Radio, Ltd. ... 79 Tannoy Products (Guy R. Fountain, British Television Supplies, Ltd. 47 Ltd.)...... 86 Burndept, Ltd...... 85 Telsen Electric Co. (1935), Ltd. 90 Bush Radio, Ltd...... 70 Whiteley Electrical Radio Co., Ltd. ... 75 Cole, Ltd., E. K...... 69 101 (Continued on next page.) CLASSIFIED DIRECTORY OF EXHIBITS—continued.

STAND NO. STAND NO. Radio Gramophones.—Continued. Radio Receivers, Battery Operated.— Cossor, Ltd., A. C...... 61 Continued. Decca ...... 71 Lissen, Ltd. ... 73 Dynatron Radio, Ltd...... 104 Marconiphone Co., Ltd. 53, 64 Elf, Ltd., Gordon ...... 95 McMichael Radio, Ltd. ... 59 Ferranti, Ltd...... 74 Milnes Radio Co., Ltd. 88 General Electric C6., Ltd. 54,62 Mullard Wireless Service Co., Ltd. 72 Halcyon Radio, Ltd...... 35 Pilot Radio, Ltd...... 84 Haynes Radio, Ltd...... 11 Portadyne Radio ...... 18 His Masters Voice ...... 66, 76 Pye, Ltd...... 60 Marconiphone Co., Ltd. 53, 64 Regentone Products, Ltd. 97 McMichael Radio, Ltd. ... 59 Stratton & Co., Ltd...... 23 Philips Lamps, Ltd. 68 Texaloom Radio, Ltd. ... 15 Pilot Radio, Ltd...... 84 Ultra Electric, Ltd. 63 Portadyne Radio ...... 18 Vidor, Ltd...... 33 Pye, Ltd...... 60 Whiteley Electrical Radio Co., Ltd. ... 75 Radio Gramophone Development Co., Ltd...... 67 Regentone Products, Ltd...... 97 Radio Receivers, Mains Operated. Tannoy Products (Guy R. Fountain Ace Radio, Ltd...... 103 Ltd.)...... 86 Aerodyne Radio, Ltd...... 52 Texaloom Radio, Ltd. 15 Balcombe, Ltd., A. J...... 55 Ultra Electric, Ltd. ... 63 Beethoven Radio, Ltd. 34 British Belmont Radio, Ltd. ... 79 British Television Supplies, Ltd. 47 Radio and Other Journals. Bumdept, Ltd...... 85 tcB.B.C. Empire Broadcasting” ... 78 Bush Radio, Ltd...... 70 “Broadcaster” T2 Cole, Ltd., E. K. 69 “ Cyclist ” ...... 10 Cossor, Ltd., A. C...... 61 “Efficiency Magazine” 221 Decca ...... 71 “ Electrical Engineer ” 10 Dynatron Radio, Ltd. ... 104 “ Electrical Trading ” T2 Eddystone Radio 23 “Listener” ...... 78 Elf, Ltd., Gordon 95 “ Popular Wireless & Television Times ” 13 Ever Ready Radio, Ltd. 58 “ Practical & Amateur Wireless ” ... 10 Ferranti, Ltd...... 74 “ Practical Mechanics ” 10 Gambrell Electrical Equipment Co., “ Practical Motorist ”...... 10 Ltd...... 14 R.M.A. “ Radio Service Manual ” ... 40 General Electric Co., Ltd. 54, 62 “ Radio Pictorial ” 105 Halcyon Radio, Ltd...... 35 “Radio Times”...... 78 Haynes Radio, Ltd...... 11 “ Service Engineer ” ...... T2 His Master’s Voice ...... 66,76 “ Service Man’s Manual ” ... T2 Invicta Radio, Ltd...... 56 “Television and Short Wave World” 105 Kolster-Brandes, Ltd. ... 65 “ Wireless & Electrical Trader ” ... T1 Lissen, Ltd...... 73 “ Wireless Engineer ”...... 7 Marconiphone Co., Ltd. 53, 64 “ Wireless Trader ” Year Book T1 McMichael Radio, Ltd. ... 59 “ Wireless World ” ...... 7 Milnes Radio Co., Ltd. 88 “World Radio” ...... 78 Mullard Wireless Service Co., Ltd. 72 Philips Lamps, Ltd...... 68 Pilot Radio, Ltd...... 84 Radio Receivers, Battery Operated. Portadyne Radio ...... 18 Ace Radio, Ltd...... 103 Pye, Ltd...... 60 Aerodyne Radio, Ltd...... 52 Radio Gramophone Development Co., Balcombe, Ltd., A. J...... 55 Ltd...... 67 Beethoven Radio, Ltd. 34 Regentone Products, Ltd...... 97 British Belmont Radio, Ltd. ... 79 Stratton & Co., Ltd...... 23 British Television Supplies, Ltd. 47 Texaloom Radio, Ltd...... 15 Bumdept, Ltd...... 85 Ultra Electric, Ltd. 63 Bush Radio, Ltd. 70 Vidor, Ltd. .. 33 Cole, Ltd., E. K. 69 Whiteley Electrical Radio Co., Ltd. ... 75 Cossor, Ltd., A. C. 61 Decca ...... 71 Radio Receivers, Universal, A.C.-D.C. Eddystone Radio 23 Elf, Ltd., Gordon 95 Ace Radio, Ltd...... 103 Ever Ready Radio, Ltd. 58 Aerodyne Radio, Ltd...... 52 Ferranti, Ltd...... 74 Balcombe, Ltd., A. J...... 55 General Electric Co., Ltd. 54,62 Beethoven Radio, Ltd...... 34 Halcyon Radio, Ltd...... 35 British Belmont Radio, Ltd. ... 79 His Master’s Voice 66, 76 Bumdept, Ltd. ... 85 Invicta Radio, Ltd. ... 56 Bush Radio, Ltd. 70 Kolster-Brandes, Ltd...... 65 Cole, Ltd., E. K...... 69 162 (Continucdjm next page.) CLASSIFIED DIRECTORY OF EXHIBITS—continued.

STAND NO. STAND NO. Radio Receivers, Universal, A.C.-D.C.— Radio Receivers, Superheterodyne.— Continued. Continued. Cossor, Ltd., A. C...... 61 Kolster-Brandes, Ltd...... 65 Elf, Ltd., Gordon ...... 95 Lissen, Ltd...... 73 Ferranti, Ltd...... 74 Marconiphone Co., Ltd. 53,64 General Electric Co., Ltd. 54, 62 McMichael Radio, Ltd. ... 59 Halcyon Radio, Ltd...... 35 Milnes Radio Co., Ltd. ... 8J His Master’s Voice ...... 66, 76 Mullard Wireless Service Co., Ltd. 72 Invicta Radio, Ltd. ... 56 Philips Lamps, Ltd...... 68 Kolster-Brandes, Ltd...... 65 Pilot Radio, Ltd...... 84 Lissen, Ltd. .. 73 Portadyne Radio ...... 18 Marconiphone Co., Ltd. 53, 64 Pye, Ltd...... 60 McMichael Radio, Ltd. ... 59 Radio Gramophone Development Co., Mullard Wireless Service Co., Ltd. 72 Ltd...... 67 Philips Lamps, Ltd...... 68 Regentone Products, Ltd...... 97 Pilot Radio, Ltd...... 84 Stratton & Co., Ltd...... 23 Portadyne Radio ...... 18 Ultra Electric, Ltd...... 63 Pye, Ltd...... 60 Vidor, Ltd. 33 Radio Gramophone Development Co.: Whiteley Electrical Radio Co., Ltd. ... 75 Ltd...... 67 Regentone Products', Ltd. 97 Texaloom Radio, Ltd. ... 15 Ultra Electric, Ltd. 63 Radio Receivers, Short Wave. (See also Vidor, Ltd. ... 33 All Wave.) Eddystone Radio ... 23 McMichael Radio, Ltd. ... 59 Radio Receivers, Portable. Stratton & Co., Ltd...... 23 Aerodyne Radio, Ltd...... 52 Beethoven Radio, Ltd. 34 British Television Supplies, Ltd. 47 Radio Receivers, All Wave. Bumdept, Ltd...... 85 Bush Radio, Ltd...... 70 Ace Radio, Ltd...... 103 Cole, Ltd., E. K...... 69 Aerodyne Radio, Ltd...... 52 Decca ...... 71 Balcombe, Ltd., A. J...... 55 Elf, Ltd., Gordon ...... 95 Beethoven Radio, Ltd...... 34 Ever Ready Radio, Ltd. 58 British Belmont Radio, Ltd. ... 79 Ferranti, Ltd...... 74 British Television Supplies, Ltd 47 General Electric Co., Ltd. 54,62 Bumdept, Ltd...... 85 His Master’s Voice ...... 66, 76 Bush Radio, Ltd...... 70 Lissen, Ltd...... 73 Cole, Ltd., E. K...... 69 Marconiphone Co., Ltd. 53, 64 Cossor, Ltd., A. C...... 61 McMichael Radio, Ltd. ... 59 Decca ...... 71 Portadyne Radio ...... 18 Dynatron Radio, Ltd...... 104 Pye, Ltd...... 60 Eddystone Radio ...... 23 Vidor, Ltd...... 33 Elf, Ltd., Gordon ...... 95 Whiteley Electrical Radio Co., Ltd. 75 Ever Ready Radio, Ltd. 58 Ferranti, Ltd...... 74 Gambrell Electrical Equipment Co., Radio Receivers, Superheterodyne. Ltd...... 14 General Electric Co., Ltd. 54,62 Ace Radio, Ltd...... 103 Halcyon Radio, Ltd...... 35 Aerodyne Radio, Ltd...... 52 His Master’s Voice ...... 66,76 Balcombe, Ltd., A. J...... 55 Invicta Radio, Ltd...... 56 Beethoven Radio, Ltd...... 34 Kolster-Brandes, Ltd...... 65 British Belmont Radio, Ltd. ... 79 Lissen, Ltd...... 73 British Television Supplies, Ltd. 47 Marconiphone Co., Ltd. 53,64 Bumdept, Ltd...... 85 McMichael Radio, Ltd. ... 59 Bush Radio, Ltd...... 70 Milnes Radio Co., Ltd. 88 Cole, Ltd., E. K...... 69 Mullard Wireless Service Co., Ltd. 72 Cossor, Ltd., A. C...... 61 Philips Lamps, Ltd...... 68 Decca ...... 71 Pilot Radio, Ltd...... 84 Dynatron Radio, Ltd...... 104 Portadyne Radio ...... 18 Eddystone Radio ...... 23 Pye, Ltd...... 60 Elf, Ltd., Gordon 95 Radio Gramophone Development Co., Ever Ready Radio, Ltd. 58 Ltd...... 67 - Ferranti, Ltd...... 74 Regentone Products, Ltd ... 97 General Electric Co., Ltd. 54, 62 Stratton & Co., Ltd...... 23 Halcyon Radio, Ltd...... 35 Texaloom Radio, Ltd.... 15 Harries Thermionics, Ltd. 3 Ultra Electric, Ltd. ... 63 His Master’s Voice ...... 66, 76 Vidor, Ltd...... 33 Invicta Radio, Ltd...... 56 Whiteley Electrical Radio Co., Ltd. ... 75 163 (Continued on next •page.) CLASSIFIED DIRECTORY OF EXHIBITS—continued.

STAND NO. STAND NO. Radio Receivers for Motor Cars. Short Wave Converters & Components. Ferranti, Ltd...... 74 Bulgin & Co., Ltd., A. F. 1 Eastick & Sons, J. J...... T3 Eddystone Radio 23 Stratton & Co., Ltd...... 23 Record Changers. Telsen Electric Co. (1935), Ltd. ... 90 Collaro, Ltd...... 101 Garrard Engg. & Mfg. Co., Ltd. ... 37 Signal Lamps. Bulgin & Co., Ltd., A. F. 1 Record-Playing Units. Collaro, Ltd...... 101 Signal Generators. Cosmocord, Ltd. ... 48 Hunt, Ltd., A. H...... 155 Garrard Engg. & Mfg. Co., Ltd. ... 37 Telsen Electric Co. (1935), Ltd. ... 90

Solder, Soldering Irons & Tools, etc. Rectifiers, Metal. Henley’s Telegraph Works Co., Ltd., Westinghouse Brake & Signal Co., Ltd. 77 W. T...... 20 Norman Rose (Electrical), Ltd 207 Rawlplug Co., Ltd. ... 91

Remote Controls. Soldering Tags. Bulgin & Co., Ltd., A. F. 1 Bifurcated & Tubular Rivet Co., Ltd. 151 Pye, Ltd...... 60

Switches. Resistances, Fixed & Variable. Bulgin & Co., Ltd., A. F. 1 Eastick & Sons, J. J...... T3 Bulgin & Co., Ltd., A. F. 1 Milnes Radio Co., Ltd. 88 Dubilier Condenser Co. (1925), Ltd. 81 Plessey Co., Ltd...... 22 Norman Rose (Electrical), Ltd. ...207 Telsen Electric Co. (1935), Ltd. 90 Plessey Co., Ltd...... 22 Whiteley Electrical Radio Co., Ltd. 75 Varley (Oliver Pell Control, Ltd.) 99 ... 44 Wingrove & Rogers, Ltd. ... 44 Wingrove & Rogers, Ltd.

Television Components. Baird Television, Ltd...... 87 Rivets and Riveting Machines. Belling & Lee, Ltd...... 42 Bifurcated & Tubular Rivet Co., Ltd. 151 British Television Supplies, Ltd. 47 Edison Swan Electric Co., Ltd. 57 Haynes Radio, Ltd...... 11 His Master’s Voice ...... 66, 76 Scales. British Metal Engraving Co., Ltd. ... 158 May & Baker, Ltd. ... 157 Television Camera. His Master’s Voice 66, 76

Service Equipment & Service Books. Television Receivers. Automatic Coil Winder & Electrical Equipment Co., Ltd. 30, 166 Baird Television, Ltd...... 87 Cossor, Ltd., A. C...... 61, 163 British Television Supplies, Ltd. 47 Everett Edgcumbe & Co., Ltd. 164 Cole, Ltd., E. K...... 69 Ferranti, Ltd...... 21 Cossor, Ltd., A. C...... 61 Hunt, Ltd., A. H...... 155 Edison Swan Electric Co., Ltd. 57 Mullard Wireless Service Co., Ltd. 161 Ferranti, Ltd...... 74 Norman Rose (Electrical), Ltd. 207 . General Electric Co., Ltd. 54,62 Radio Manufacturers* Association 40 Halcyon Radio, Ltd...... 35 Radiometers, Ltd. 162 Haynes Radio, Ltd...... 11 Salford Electrical Instruments, Ltd. 168 His Master’s Voice ...... 66,76 Telsen Electric Co. (1935), Ltd. 90 Invicta Radio, Ltd...... 56 Weston Electrical Instrument Co., Ltd. 167 Kolster-Brandcs, Ltd. ... 65 Wright & Weaire, Ltd. ... 165 Marconiphone Co., Ltd. 53, 64 164 {Continued on next page.) r CLASSIFIED DIRECTORY OF EXHIBITS—continued.

STAND NO. STAND NO. Television Receivers.—Continued. Valves & Rectifiers. British Pix Co., Ltd...... 211 Philips Lamps, Ltd...... 68 British Tungsram Radio Works, Ltd. 36 Pye, Ltd. ... 60 Cossor, Ltd., A. C...... 61 Radio Gramophone Development Co., Edison Swan Electric Co., Ltd. 57 Ltd...... 67 Ever Ready Radio, Ltd. 58 Ultra Electric, Ltd. ... 63 Ferranti, Ltd...... 74 General Electric Co., Ltd. 54,62 ' Terminals, Screws, etc. Harries Thermionics, Ltd. 3 High Vacuum Valve Co., Ltd. 27 Belling & Lee, Ltd...... 42 Mullard Wireless Service Co., Ltd. ... 72 ! British Mechanical Productions, Ltd. 94 The 362 Radio Valve Co., Ltd. ... 210 Davis & Timmins, Ltd. ... 213 Valve Holders. i Testing Equipment & Instruments. Belling & Lee, Ltd. ... 42 Benjamin Electric, Ltd. ... 17 Automatic Coil Winder & Electrical British Mechanical Productions, Ltd. 94 Equipment Co., Ltd. ... 30, 166 Bulgin & Co., Ltd., A. F. 1 Cossor, Ltd., A. C...... 61, 163 Eddystone Radio 23 Crypton Equipment, Ltd...... 202 Plessey Co., Ltd. 22 Everett Edgcumbe & Co., Ltd. ... 164 Stratton & Co., Ltd. ... 23 Ferranti, Ltd...... 21 Whiteley Electrical Radio Co., Ltd. ... 75 Hunt, Ltd., A. H...... 155 Mullard Wireless Service Co., Ltd. ... 161 Norman Rose (Electrical), Ltd. .. 207 Valve Pins. Radiometers, Ltd...... 162 British Mechanical Productions, Ltd. 94 Salford Electrical Instruments, Ltd. ... 168 Telsen Electric Co. (1935), Ltd. .. 90 Vibrators. Weston Electrical Instrument Co., Ltd. 167 All-Power Transformers, Ltd. ... 209 Wright & Weaire, Ltd. ... 165 Bulgin & Co., Ltd., A. F. 1 . Tools. Volume Controls. {See also Potentiometers.') Rawlplug Co., Ltd. ... 91 British Centralab, Ltd. ... 153 r Bulgin & Co., Ltd., A. F. 1 Norman Rose (Electrical), Ltd. 207 Torches & Torch Batteries. Varley (Oliver Pell Control, Ltd.) 99 Wingrove & Rogers, Ltd. ... 44 Aerialite, Ltd...... 28 : British G.W.Z Battery Co., Ltd. 82 I Ever Ready Radio, Ltd. 58 Wander Plugs. Lissen, Ltd...... 73 Belling & Lee, Ltd. ... 42 1. Siemens Electric Lamps & Supplies, British Mechanical Productions, Ltd. 94 !» Ltd...... 31 Sterling Batteries, Ltd. 5 Wholesale Distributors, General Display. Brown Bros., Ltd. ... T18 T ransfor mer s. Cadisch & Sons, R. ... T9 All-Power Transformers, Ltd. 209 Dew & Co., Ltd., A. J. T20 Bulgin & Co., Ltd., A. F. 1 Dibben, Ltd., Horace ... T8 Ferranti, Ltd...... 74 Dyson & Co., Ltd., J. ... T14 Haynes Radio, Ltd...... 11 Eastick & Sons, J. J. ... T3 Heayberd & Co., F. C. 25 East London Rubber Co., Ltd T16 Plessey Co., Ltd...... 22 Flinders Wholesale, Ltd. T7 Reslo (Sound Equipment), Ltd. 24 Gilbert & Co., C. T17 Sound Sales, Ltd...... 89 Harris & Russell, Ltd. T12 ;• Telsen Electric Co. (1935), Ltd. 90 Hillman Brothers, Ltd. 216 ■ Varley (Oliver Pell Control, Ltd.) 99 Hobday Bros., Ltd. T10 Wingrove & Rogers, Ltd. 44 Houghtons, (Ensign Ltd.) T19 - ■ i L. E. S. Distributors, Ltd. ... T6 i Lugton & Co., Ltd...... T15 ! Transmitting Apparatus. (See Micro­ Manufacturers Accessories Co. (1928), phones.) Ltd...... T4 Selecta Gramophones, Ltd. ... T13 Thompson Diamond & Butcher, Ltd. T5 Tuning Units. (See also Coils.) Webber & Co., Ltd., J. M...... Til Ardentc (R. H. Dent, Ltd.) ... 2 ;]• Wires and Cables. Turntables. Aerialite, Ltd...... 28 Garrard Engg. & Mfg. Co., Ltd. ... 37 Rists* Wires & Cables, Ltd...... 159 ... 62 Scott Insulated Wire Co., Ltd. ... 156 1 General Electric Co., Ltd. ■ 165 STAND Nos.

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THE

Radio Manufacturers’ Association.

LIST OF MEMBERS.

i Aerialite, Ltd. ... Castle Works, Stalybridge, Cheshire. Aerodyne Radio, Ltd. ... Aerodyne Works, Tottenham, N. 17. Aeronautical & General Instru­ ments, Ltd. ... Purley Way, Croydon, Surrey. Automatic Coil Winder & Elec­ trical Equipment Co., Ltd. ... Winder House, Douglas Street, S.W.l.

Baird Television, Ltd. ... Greener House, 66, Haymarket, S.W.l. Balcombe, Ltd., A. J. ... 52-58, Tabernacle Street, E.C.2. Beethoven Radio, Ltd. ... Chase Road, North Acton, N.W.10. Belling & Lee, Ltd. ... Cambridge Arterial Road, Enfield, Middlesex. Benjamin Electric, Ltd...... Brantwood Works, Tariff Road, N.17. Bird & Sons, Ltd., Sydney S. (Cyldon Radio)...... Cyldon Works, Cambridge Arterial Road, Enfield. Bridger & Co., Ltd., R. O. ... 4, Shelford Place, Church Street, N.16. Britannia Batteries, Ltd...... Union Street, Redditch, Worcestershire. British Mechanical Productions, Ltd. ... 79a, Rochester Row, S.W. 1. British N. S. F. Co., Ltd. ... Waddon Factory Estate, Croydon, Surrey. i British Rola Co., Ltd. ... Minerva Road, Park Royal, N.W.10. British Thomson-Houston Co., Ltd. Crown House, Aldwych, W.C.2. Bulgin & Co., Ltd., A. F. ... Abbey Road, Barking, Essex. Burndept, Ltd...... Light Gun Factory, Erith, Kent. Burne-Jones & Co., Ltd...... 309, Borough High Street, S.E.l. Bush Radio, Ltd...... Power Road, Chiswick, W.4.

Carr Fastener Co., Ltd...... Nottingham Road, Stapleford, Nottingham. Carrington Mfg. Co., Ltd. ... “ Cameo ” Works, Sanderstead Road, S. Croydon. Celestion, Ltd...... London Road, Kingston-on-Thames. Chloride Electrical Storage Co., Ltd...... 205-231, Shaftesbury Avenue, W.C.2. City Accumulator Co., Ltd. ... 18-20 Norman’s Buildings, Central Street, E.C.l. 167 (Continued on next page.) List of Members of The Radio Manufacturers' Association—(continued).

Cole, Ltd., E. K...... “ Ekco ” Works, Southend-on-Sea, Essex. Collaro, Ltd. ... Culmore Works, Culmore Road, Peckham, S.E.15. Colvern, Ltd. ... Mawneys Road, Romford, Essex. Cossor, Ltd., A. C...... Cossor House, Highbury Grove, N.5. Cyldon Radio (Sydney S. Bird & Sons, Ltd.) ... Cyldon Works, Cambridge Arterial Road, Enfield.

Darwins, Ltd...... Fitzwilliam Works, Sheffield. Davies (Slough), Ltd., D. M. ... Trading Estate, Slough, Bucks. De la Rue & Co., Ltd., Thos. ... 90, Shemhall Street, Walthamstow, E.17. Dubilier Condenser Co. (1925), Ltd. Ducon Works, Victoria Road, North Acton, W.3. Dynatron Radio, Ltd. ... Perfecta Works, Ray Lea Road, Maidenhead. Dyson & Co. (Works), Ltd., J. ... 5, Godwin Street, Bradford.

Eddystone Radio (Stratton & Co., Ltd.) ... Eddystone Works, Bromsgrove St., Birmingham. Edison Swan Electric Co., Ltd. ... 155, Charing Cross Road, W.C.2. Erie Resistor, Ltd...... Carlisle Road, The Hyde, Hendon, N.W.9. Ever Ready Co. (Gt. Britain), Ltd. Ever Ready Works, Hercules Place, Holloway, N.7.

Faraday Radio-Gramophones, Ltd. 8, Bridewell Place, E.C.4. Ferranti, Ltd. ... Radio Works, Moston, Manchester. Fuller Accumulator Co. (1926), Ltd. Woodland Works, Chadwell Heath, Essex.

Garrard Engineering & Manufac­ turing Co., Ltd. ... Newcastle Street, Swindon, Wilts. General Electric Co., Ltd. ... Magnet House, Kingsway, W.C.2. Goodmans Industries, Ltd. ... Lancelot Road, Wembley, Middlesex. Gramophone Co., Ltd. ... 98-108, Clerkenwell Road, E.C.l. Grampian Reproducers, Ltd. ... Station Avenue, Kew Gardens, Surrey.

Halcyon Radio, Ltd. ... Sterling Works, Dagenham, Essex. Hartley Turner Radio, Ltd. ... Thornbury Road, Isleworth, Middlesex. Heayberd & Co., F. C. ... 10, Finsbury Street, E.C.2.

Igranic Electric Co., Ltd. ... 147, Queen Victoria Street, E.C.4. Invicta Radio, Ltd...... 79a, Parkhurst Road, N.7.

Jackson Brothers (London), Ltd. ... 72, St. Thomas Street, S.E.l.

Kolster-Brandes, Ltd. ... Cray Works, Sidcup, Kent.

Levick & Sons, Ltd., Swift ... Clarence Steel Works, Sheffield. Lissen, Ltd...... Angel Road, Edmonton, N.18. London Electric Wire Co. & Smiths, Ltd. ... Church Road, Leyton, E.10. 168 {Continued on next page.) List of Members of The Radio Manufacturers' Association— (continued). i Mains Radio Gramophones, Ltd. ... Vaughan Street, Bradford. : Marconiphone Co., Ltd...... 210, Tottenham Court Road, W.l. McMichael Radio, Ltd. ... Wexham Road, Slough, Bucks. - I Milnes Radio Co., Ltd. ... Victoria Works, Church Street, Bingley, Yorks. Morgan Crucible Co., Ltd. ... Battersea Works, Church Road, S.W.ll. Muirhead & Co., Ltd. ... Elmers End, Beckenham, Kent. Mullard Radio Valve Co., Ltd. ... Milliard House, 225, Tottenham Court Road, W.l. Multitone Electric Co., Ltd. ... 95, White Lion Street, Islington, N.l.

National Accumulator Co., Ltd. ... 50, Grosvenor Gardens, S.W.l. ! New London Electron Works, Ltd. East Ham, London, E.6.

Oliver Pell Control, Ltd. (Varley) Cambridge Place, Woolwich, S.E.18.

Parmeko, Ltd...... Percy Road, Aylcstone Park, Leicester. Partridge Wilson & Co., Ltd. ... Davenset Works, Evington Valley Road, Leicester. ! Philips Lamps, Ltd...... 145, Charing Cross Road, W.C.2. Plessey Co., Ltd. ... Vicarage Lane, Ilford, Essex. I Pye, Ltd...... Radio Works, Cambridge.

Quadrant Carbon & Metal Pro­ ducts, Ltd. ... Quadrant Works, Cumberland Road, Stanmore, Middlesex.

Radio Gramophone Development Co., Ltd...... Globe Works, Newtown Row, Birmingham, 6. Reproducers & Amplifiers, Ltd. ... Frederick Street, Wolverhampton. Rist’s Wires & Cables, Ltd. ... Waveney Works, Lowestoft.

Scott Insulated Wire Co., Ltd. ... Queensland Works, Holloway, N.7. Siemens Electric Lamps & Supplies, Ltd. ... 39, Upper Thames Street, E.C.4. Smurthwaite, Ltd., F. W...... Harmony Works, Ross Parade, Wellington, Surrey. Standard Telephones & Cables, Ltd. Connaught House, Aldwych, W.C.2. Steatite & Porcelain Products, Ltd. Stourport-on-Sevem, Worcestershire. Stratton & Co., Ltd. (Eddystone

Radio) ...... Eddystone Works, Bromsgrove Street, Birmingham. . ■ ;

Tannoy Products ... Canterbury Grove, West Norwood, S.E.27. Telegraph Condenser Co., Ltd. ... Wales Farm Road, N. Acton, W.3. Telephone Manufacturing Co., Ltd. Hollingsworth Works, West Dulwich, S.E.21. I Telsen Electric Co. (1935), Ltd.... Fitzgeorge Street, Rochdale Road, Manchester, 9.

Ultra Electric, Ltd. ... Western Avenue, Acton, W.3.

Webb Condenser Co., Ltd. ... 42, Hatton Garden, E.C.l. Westinghouse Brake & Signal Co., Ltd. ... 82, York Road, King’s Cross, N.l. : Whiteley Electrical Radio Co., Ltd. Victoria Street, Mansfield, Notts. Wingrove & Rogers, Ltd...... Mill Lane, Old Swan, Liverpool. Wright & Weaire, Ltd. ... 740, High Road, Tottenham, N.17. I 169 i ;• _ MEMORANDA. /

/

i

/

v >

'

\ I

170 / i

! INDEX TO ADVERTISERS. «

Page Page A L Accrington Development Committee ... 152 Lissen, Ltd. ... 94 Aerialite, Ltd. ... 110 Automatic Coil Winder & Electrical M Equipment Co., Ltd. ... 1, 2, 4, 26, 166 McMichael Radio, Ltd...... 68 B Marconiphone Co., Ltd...... 60 Balcombe, Ltd., A. J...... 14 Mather & Crowther, Ltd. ... 28 Bowmaker, Ltd...... 136 Mayfair Window Cleaning Co., Ltd. ... 138 Bridger & Co., Ltd., R. O. ... 152 Mica & Micanite Supplies, Ltd. ... 120 British Broadcasting Corporation ... 154 Milnes Radio Co., Ltd...... 108 British Rola Co., Ltd...... 54 Mullard Wireless Service Co., Ltd. ... 92 British Tungsram Radio Works, Ltd. ... 123 Brooks & White ...... 150 N C Newnes, Ltd., George ... 34 “ News Chronicle ” ... 110 Celestion, Ltd. ... 42 “ News of the World ” ...... 122 Cole, Ltd., E. K. ... Inside Front Cover I Collaro, Ltd. ... 116 O Colwyn Bay Wireless College ... 129 Olympia, Ltd. ... 76 Cook’s Furnishing Stores, Ltd., Charles 106 Cossor, Ltd., A. C. ... 72 P D Perton, A...... 44 Philips Lamps, Ltd. ... Inside Back Cover “ Daily Express ” ... 98 “ Practical Wireless ” ...... 34 I “Daily Herald” ...... 40 * “Daily Mail” ...... 32 R “ Daily Sketch ” ...... 84 Radio Gramophone Development Co., Darwins, Ltd. ... 70 Ltd. ... 86 E Radio Manufacturers’ Associatio ... 124 Radio Service Manual ... 124 Eavestaff & Sons, Ltd., W. G...... 132 Radio Society of Great Britain ... 134 “ Evening Chronicle ” ...... 74 Reslo (Sound Equipment), Ltd. ... 134 “ Evening Standard ” ...... 66 Rists’ Wires & Cables, Ltd. ... 152 F Ferranti, Ltd. 96, 97 S Film Industries, Ltd. ... 112 Sankey & Sons, Ltd., Joseph ... 36 G “ The Star ” ...... 130 Straker Brothers, Ltd...... 46 Garrard Engineering & Mfg. Co., Ltd. ... 52 Strutt & Son, F...... 38 Gee & Co...... 27 “ Sunday Pictorial ” ...... 126 Gramophone Co., Ltd...... 80 H T His Master’s Voice ... 80 “ The Times ” ...... 48 I Tucker Eyelet Co., Ltd., Geo...... 130 Iliffe & Sons, Ltd. ... 16 U j Ultra Electric, Ltd. ...Back Cover3 Spine Jackson Bros. (London), Ltd. . ... 112 Jeyes’ Sanitary Compounds Co., Ltd. ... 140 w K Wireless College, Colwyn Bay ...... 129 Kolster-Brandes, Ltd. ... 12 “ Wireless World ” ...... 16 171 OFFICERS

RADIO MANUFACTURERS’ ASSOCIATION*

PRESIDENT : The Rt. Hon. LORD GAINFORD, P.C. VICE-PRESIDENTS : The Rt. Hon. LORD HIRST of WITTON. \V. W. BURNHAM, F.Inst.R.E. Lt.-Col. j. t. c. moore-brabazon, S. WILDING COLE, O.B.E. M.C., M.P. R. MILWARD ELLIS, M.I.E.E. Col. Sir THOMAS POLSON, K.B.E., LESLIE McMICHAEL, M.I.E.E., C.M.G. F.Inst.R.E. Capt. Sir IAN FRASER, C.B.E. EDWARD E. ROSEN. S. R. MULLARD, M.B.E., M.I.E.E. J. H. WILLIAMS.

CHAIRMAN: M. M. MACQUEEN.

VICE-CHAIRMAN : Major L. H. PETER, M.C., A.F.C., M.I.E.E.

HON. TREASURER : J. JOSEPH, M.I.E.E.

TRUSTEES: W. W. BURNHAM, F.Inst.R.E. J. JOSEPH, M.I.E.E. LESLIE McMICHAEL, M.I.E.E., F.Inst.R.E.

EXECUTIVE COUNCIL: A. J. BALCOMBE, Ltd. KOLSTER-BRANDES, Ltd. BELLING & LEE, Ltd. McMICHAEL RADIO, Ltd. A. F. BULGIN & CO., Ltd. MARCONIPHONE CO., Ltd. CHLORIDE ELECTRICAL STORAGE MULLARD RADIO VALVE CO., Ltd. CO., Ltd. PHILIPS LAMPS, Ltd. E. K. COLE, Ltd. PYE, Ltd. A. C. COSSOR, Ltd. TANNOY PRODUCTS. DUBILIER CONDENSER CO. (1925), Ltd. ULTRA ELECTRIC, Ltd. EDISON SWAN ELECTRIC CO., Ltd. WESTINGHOUSE BRAKE & SIGNAL FERRANTI, Ltd. CO., Ltd. GENERAL ELECTRIC CO., Ltd. WINGROVE & ROGERS, Ltd.

EXHIBITIONS COMMITTEE: M. M. MACQUEEN (Chairman). EDWARD E. ROSEN. (General Electric Co., Ltd.) (IUltra Electric, Ltd.) W. W. BURNHAM, F.Inst.R.E. (Edison Swan Electric Co., Ltd.) H. SLATER. R. MILWARD ELLIS, M.I.E.E. (Philips Lamps, Ltd.) (Eye, Ltd.) J. H. THOMAS. Col. G. D. OZANNE, M.C., M.I.E.E. (A. C. Cossor, Ltd.) (Wingrove & Rogers Ltd.) Major L. H. PETER, M.C., A.F.C., M.I.E.E. J. H. WILLIAMS. (Westinghouse Brake & Signal Co.3 Ltd.) CMarconiphone Co.3 Ltd.)

DIRECTOR: SECRETARY: EXHIBITIONS ORGANISER: D. GRANT STRACHAN. R. P. BROWNE, B.Sc. A. E. MOODY.

OFFICES: Astor House, Aldwych, London, W.C.2. 172 i

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