.111111~~Vol.V1 No.6 June 1977 Monthly except during July and August Price !!5.50 yearly Single Issue 75#

Office Address: 9820 Silver Meadow Drive. Dallas, Texas 75217

THE NEWSPAPER FORTHE HOBBYIST OF VINTAGEELECTRONICS AND SOUND

HE HORN SPRadio News for November, 1921

High Class Workmanship in Amateur Radio ApparatusBy ARTHUR H. LYNCH

P

THERE was a day, not so very longago, when America had to bend herknee in homage to the efficiency of

the foreign worker. Germany, France andEngland were unquestionably our peers, inthe manufacture of all kinds of in-struments which were mechanicallyand scientifically correct.

Today there is a different story totell. The accompanying illustrationsbear witness to the fact that, i

workmanship, design and ease of op-eration and control. not to mentionthe appearance, it is now time forforeign manufacturers of radio ap-paratus to take off their hats toAmerica.

The story of bakelite is a very in-teresting one, for it has changed thewhole color of the insulating indus-try. Most of us remember when itwas introduced and vied with vulcan-ite for supremacy as material for front paneland turned dials and knobs. Today, it isfound moulded in all forms, made to suitthe specific requirements of the unit in whic'i

Opera Singer Heard300 Miles Away

CONCERTS by Radio are now commonthings, and in all the exhibitions of amore or less technical nature, a Radio-

phone station is used to "tell the world" ofthe doings at this particular show.

At the Electrical Show, held in the 71stRegiment Armory in New York City re-cently, such a station was installed andbroadcasted daily some information andnews.

In the evening, a concert was given byRadio to an audience spread over a widearea, and well-known artists, singers ormusicians of the opera company, could beheard quite distinctly, thanks to a perfectmodulation.

On the rightthe photo-graphs show-ing the in-terior of ama-teur receivingsets give anidea of thedegree of per-fection at-tained in themanufactureof such ap-paratus byAmericanfirms. Com-pare theworkmanshipand compact-ness of theseInstrumentswith those ofearlier days.On the leftis a close-upof a vario -meter mount-ed on amoulded com-positionframe.

llllllllll 1111.1.

it is used. It is now cheaper, can be turnedout more rapidly and the finished product ismore pleasing to the eye and more accuratein its dimensions than could previously bemade by the hand of the most skilled worker.

The wave -length range is from 15o to 3,000meters, and it is controlled by three knobs.Telephone jacks permit the use of an ex-ternal detector, if it is desired, the detectortube of the set itself, or one or two stages

of amplification. Posts are providedfor the rJnnection of a "Loud Speak-er," while all the connections for thebatter es for the tubes are made tobinding posts, through apertures inthe rear of the cabinet.

The view of the interior reveals thecharades of workmanship, which isnow putting American amateur radioapparatus ín a class by itself. Aninterior of another receiver is alsoshown, i order to give a more de-tailed explanation of some of the newadr very improved features incorpo-ra ed in modern apparatus. Particu-larly stroking is the new form of va-riometer,, which is of moulded bake-

lite and is made in such a way as to ob-viate the necessity of having the Bakelitecome between the turns of the stator and

(Conftnued on page 410)

This Small Compact Amateur Set Embodies a Tuner anI aTwo -Stage Amplifier Fitted With the Very latest improve-

ments; it Tunea up to 3,000 Metsrs.

Typical of the external appearance of thisgrade of amateur radio apparatus is thecabinet set which is here shown. It will benoticed that it is complete in every detail.

Radio News for November, 1921

In this viewshowing MissAnna Casesinging infront of themicrophone,may be seenthe radio-phone stationinstalled atthe electricalshow in NewYork City,thanks towhich thou-sands of ama-teurs couldhear the con-cert in theirhomes.

Publisher, Jim Cranshaw

214-286-1673

PHONOGRAPH CENTENNIAL1877 - 1977

rotor windings. On the panel, it will beseen that aluminum screens have been pro-vided to cut out the effect of "body capacity"while adjustments are being made.

Vernier attachments have been provided,where any critical adjustment is necessaryand the construction of the verniers is in-teresting in itself. The control knob and thelittle rubber tire, which is air -inflated, aremounted on the same axle and the rubbertire bears against the inner side of the dial.The only portion of the vernier which isvisible from the outside of the cabinet isa small portion of the control knob.

The rheostats which are of the same de-sign are marked in ohms.

DAILY NEWS AND CONCERTS BYRADIO TELEPHONE.

The Westinghouse Co. has opened a radiotelephone broadcasting station at its plantin Newark, N. J., and, with the cooperationof the Newark Sunday Call, is supplyingnews and concerts which can be heard bywireless operators within a radius of 200miles.

Every night, beginning at 8:05 EasternStandard Time, an entertainment consistingof a digest of the day's news, Governmentreports and a musical entertainment aregiven. A special feature of the entertain-ments is a children's hour every Fridaynight at 7 o'clock, when songs and storiesfor the youngsters will be radiophoned.

During the World Series baseball games,every ball, strike and other play was re-ported, as soon as made, from this station,so that thousands were able to enjoy thegames. Similar service will be providedfor the major football games and other im-portant events.

The Westinghouse Newark station operates on a wave -length of 36o meters and itscall letters are WJZ. It should be easilyheard as far south as Baltimore and as farnorth as Albany, while under favorabl;conditions, the messages should be audiblein practically the entire area east of theMississippi River, and as far east as theBermuda Islands.

TIMES OPERATOR GETS PRIZEFOR WINNING CODE CONTEST.Hundreds of amateur radio telephone and

wireless telegraph operators within a radiusof zoo miles of New York a short time agcheard officials of the National AmateurWireless Association present a silver cup toB. G. Seutter, wireless operator of the NewYork Times Transatlantic radio receivingstation. Mr. Seutter received the cup forwinning the American open championship.He received code at forty-four and one-third words a minute with no mistakes.

The presentation was held in connectionwith the New York Electrical Show in theSeventy-first armory. The wireless tele-phone was used to spread the addresses andreception speeches to members of 41-e Asso-ciation. Major Andrew White, President ofthe National Amateur Wireless Associa-tion, in formally awarding the cup, pro-nounced Mr. Seutter's work "a remarkableachievement of one hundred percent per -f ection."

Arthur Williams, General Manager ofthe New York Edison Company, which do-nated the cup, was specially connected withthe armory by wireless telephone at hishome, where he was confined by illness.

Radio News for November, 1921

2The HORN SPEAKER..... 9820 Silver Meadow Drive, Dallas, Texas 75217

LETTERSThere is a new book on the marketentitled "Collecting Old Radios andCrystal sets," by Max Alth, Veryinteresting book for those whocollect and restore.Copies may be obtained for $7.95from Mid America Book Co., Leon,Iowa 50114. This company is thelargest distributor of antiquepublication in the entire midwest.For those interested, other re-ferences are available on a widearea of interests.

Dave McKenzie1200 W. EuclidIndianola, Iowa 50125

Editor...Thank you, Dave.

Dear Sir:As a subscriber to your magazine,

I would like you to take note of thefollowings1. Many of your ads are not answered

as they should be. I have sentseveral SASE's exactly as direct-ed, but have not received any re-plies: (One reply for every 3sent if luckyl)Please ask your readers to have

the courtesy of making replies. Es-pecially if SARK are enclosed:2. It also is very apparent that

when replies are sent, most ifnot all of the better sets, morefair prices, etc. are alreadygone: All that is left is usual-ly junk:As soon as I receive my copy of

The Horn Speaker, I IMMEDIATELY sendmy SASE to those ads Íwish to answerand still, most of it is gºnet

Am I receiving my copy aftereveryone else?:?

Sincerely,L. Prince1506 Argonne Dr.Albany GA 31707

Editor...Mail from Dallas to Georgiahas always seemed slow. I hope thatwe can soon change this condition.

Dear Mr. Cranshaw:Quite by accident, I found out

that many of the old types of tubesare being made again, tubes like1LH1i, 106, 1A7, 19, 214A, 26, 30 etc.

To find out if it was really true,I ordered a 1H5 GT for one of my sets.The tube looks just like the onesbuilt 30 years ago including themetal base only it is brand new andcost little more than the used onesthat we have had to use till now.

They are available from LaFayetteRadio Electronics Corp., 111 JerichoTpke., Syoset N.Y. 11791. You will

a11o1707 1143/2,I11LiklfiII,.1E ! saw teaD°atIDtI7rS or THE litatIll£Su II.II7CIfala7rtQJHt1IB002in-

. Spool

WCZ

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We bet there are alot of urltnown collector items laying around in the junk boxes,complete...just waiting for this rare literature...our reprint services are the largest,in the world...most of the original were taken from our collection...now the GREATSilent Radio Collectors have came out of the woodwork and made available their originals `so we all can benefit and share...we have many more to offer, but selected these onlybecat&of opinions from experts and our correspondence...the process is slow and weneed your support.... much of the following literature does not appear in anytypepublications today...this literature is required for historical significance, restoration,reconstruction projects, appraising, and judging...now you can have all by orderingusing the following designations: SS (service bulletin) IB (instruction book), B (brochure),CB (catalog book), M (miscellaneous).The following AMRAD Service Bulletins are very rare..educational,we have made attemptto list the details...most all contain original part and prices, wiring diagrams etc.CB001 1921 AMRAD CRYSTAL SET: Rare,very First catalog -type -bulletin issued by the

American Radio and Research Corp., to promote and sell to the general publicthis crystal set and their other products, simplified in detail..4p $2.95.

1921 -Feb -Bulletin -V: AMRAD Receiving UNITS, all units made in the first year,Each unit assigned name: LDL Variometer, SW -coupler, Crystal Receiver,Variable Condenser, VT -Detector, 2 -stage -amplifier, B -Box, each unit can becombined to form 15 different combinations..example 2 -Units coupled togetherNamed "The Twinplex", 8 -Units connected "The Pounders" ,,All internal viewsinterconnecting wiring and RARE wiring diagrams of each unit.. if you have these

in your possession...find out the names, if you don't have any you can usethis rare literature to:rebU,ltthem..all with dimensions .8pages $4.95.

SB002 1921 -March -Bulletin -P3: Induction Coil Receiving Sets, 100W system withMurdock Oscillation transformers and condensers -Bunnell Key..2p $0.95.

SB003 1921 -March -Bulletin -Q: Quenched Gaps -Types G-1-1KW, G-2-1-2KW, G-3-1-3KW,and the assigned A-2 systems first used in the U.S. Navy..4p Eí.95.

SB004 1921 -April -Bulletin -W-2: E -Type Wavemeter very rare..first unit to be used asas four functions such as WM, Variometer, Interference, & Preventer..2p $0.95.

SB005 1921 -April -Bulletin -R: All standard parts catalog-type...4 pages $1.95.SB006 1921 -August -Bulletin -Z6: RARE Part listing and Prices of all AMRAD items made

this year all with dimensions of each item where applicable..2p...$0.95.SB007 1921 -Sept. -Bulletin -L: Amrad receiving sets No. 2596, No. 2634, Detector -2 -

Stage Amplifier, well illustrated, contains all tech. information..4pages $1.95.SB008 1921 -Sept -Bulletin -N: Ampliformer No. 2620 Vernier, Variometer No. 245 parts,

rheostats, dials, condensers, tube bases, Grid Leak, etc., 4p $1,95. -SB009 1921 -Sept -Bulletin -O: New Variometer No. 2602, 2607, Variocouplers No. 11-

No.14..like all others very RARE today and well illustrated..2p $0.95.SB010 1921 -Sept. -Bulletin -T: Twin-Syn-motor No. 2551 included in the system along

with the U. S. NAVY MODEL L 1/2 KW 500 cycle Transmitter(1250.00).2p. 0.95SB011 1921 -Oct, -Bulletin -X: Rare long wave tunner-type 2492 Type -F, also listed;

ARCSETS No. 2492, 2309, 2227...profusely illustrated.. .2p $0.95.SB012 1921 AMRAD SERVICE BULLETINS BOOKLET: Save us some time by ordering

CB001, PLUS SB001 through SB011 all in one package for ONLY.....$9.95.

I13001 1925 FRESHMAN MASTERPIECE -5 tube-TRF Radios Instruction Book: By A. W.Franklin, Chief Engineer; MODELS Illustrated: 5-F-1, 5-F-2, 5-F-4, 5-F-5,5-F-6, SF -7, Concert, Masterpiece, also are schematics, tunning charts, sub:panels, Eliminators, all parts, cabinets, complete troubleshooting charts, .iteragerl.adjustments to Grid Leaks ..very interesting..well illustrated 28p...$4.95

I8003

CB002

® for those ho want to emernber.-M

have to ask for their complete tubelisting because these tubes are notlisted in their catalog.

Sincerely yours,John D. MartinP.O. Box 11!

Paloma IL

Editor...Thanks for the info.

Dear Sir:I am enclosing a check for !6.00

BACK ISSUESThe Horn Speaker

All 10 back issues for 1973...$8.00Single issues...$1.00 each

All 10 back issues for 1974...1k6.00Single issues...$.75 each

All 10 back issues for 1975...$5.00Single issues...$.75 each

All 10 back issues for ]976...15.00Single issue...$.75 each

Any single issue of 1977...$.75 eachLater, we should have completevolumes for 1972, first year.

The Horn SpeakerBox 12 Kleberg, Texas

75145

For those who want to learn... elkálw1925 FREED-EISEMANN RADIO INSTRUCTION BOOK: by Joseph D. R. Freedresident and Chief Engineer, Complete Installation and Operations data for

all models made in 1925..Antennas, reception -all types-remedies,batteries,tubes, New and Old, Loud Speakers, list of Broadcasting station -world-widebuilding these radios, memorandums PLUS Rare history of this companyphotos, illustrations varies..rare...32 pages ONLY $4.951925 FREED-EISEMANN MODEL NR7 Neutrodyne Instruction Book,photos, wehave added the schematics to this..plus you get a F-E-Radio-Log...thismaterial will display well with radio..6p..$2.95,With IB002 Both.$5.95 -1925 ELECTRIC SUPPLY AND EQUIPMENT COMPANY CATALOG NO. 14: This is

Rarest and best illustrated RADIO catalog we have ever seen.. Radio was New,the ES & EC were distributors (6 major locations Eastern) to dealers.. this isthe first catalog book published, therefore we will go into detail its contents,note each page will be suitable for framing if you want to pull it apart, here itis: Musicmaster-Ware models: 50,60,100,140,175,215,250,300,400,

460 -(each page for each model) Speakers: V, VIII, XI, XII, XIII, 14" & 21" HornSpeakers, Weston Parts; Kolster Models: 6 -A,6 -B,8 -B,8 -C, BRAN DES:Speakers HORN types -Table Talker, "H", H -type in cabinet, Cone, SuperiorHeadsets, Navy -types; Eagle modelsj, Neutrodyne D, F, Cl, C2, C3,M®ltiaaalk Models: VA, Masterdine : M-50, Tower Products:Headsets -S -T- Horn Spks: 8 1/2", 13", 14",Meistersinger, Midget Horn,

Gold Star Radio Sets: 51, Crystal, C111-1 tubes, C1122 - tuber, C113 -3 -tuber, E R LA Models:. De Luxe,Standard, all major partLoop Antennas, RCA TUBES: WD11 plus 11 others, Phil co: Parts,Batteries, chargers, Bald(i tel.. Chargers, There are many other majormanufacturers and their products listed: From clips to test equipment; Jewell,Universal, Na-ald, Allen-Bradley, Mar -Co, H&H, Dubilier, Keystone,Premier-

Ensemble Kit Radios, Karas, Py/RADIOIin,(Dupont), Raco, Bassett, Hefner,Effarsee and Eveready..75 8 1/2 x 11 pages..very educational, ONLY $9.95.

IB004 1928 CROSLEY SHOWBOX MODEL 706 Instruction Booklet..4page..$l.95.IB005 íL924 RADIOLA INSTRUCTION BROCHURE: Models: Radiola III, III Amp, III -A &

Super-Hetrodyne (second Harmonic) same as VIII only was the first semi -portablefrom,'riginal fold -out with all wiring and tube kook-up..Supplement.6p..$1J.95.

I8006 1921 Q -R -S Redtop-Radio-Tube Sales Brochure w/ all Technical Specs ...$0.95.MC01 RCA COLOR LABEL REPRINTS: These are reprinted in color from the original labels:

Model 100-A, 103 Judspeaker base, and Radiola 64 Super -Heterodyne Labels..Tow you can cut out these labels and glue to the bases of their respective speaker,e64 to cabinet (bonus) cant tell from original all 3 on same artwork...$2.00 .

MCO2 MAGNAVOX CALL LETTER COLOR SHEETS 2 sheets -brown -yellow of 1776 radiostation call letters from CBA-WEAS-WEU-toYNXW reprinted from original sheets,cut out the desired station and add them above the early -push-button radios, eachis 1/4" xl/2" will fit most any radio..a must for complete restoration..$2.00.

M003 DIAL CORD STRING AND BELT GUIDE FOR any 1938-1947 Radio: $1 +.134 StampNOTE: Need a copy of the new 1977 Radio Antiquers Directory and Collector's GUIDE

SERVICES..always changing..everything from A to Z $5.00 COLOR $9.95 .IMPORTANT: 11:1D9D;U5 ®7rB$I£D4117IISIE SIMMERED ALL BOOKS S ,r HIPPED Ddo®DIRATE: For First Class ADD $3 per book,Special Handling to 2lbs .504, some weighover; Insurance extra 404, 80 to $100, Calif. Residents 6% Tax if in doubt leave yourcheck Blank, We Fill -IN n4f'or REFUND Excess, PLEASE any INQUIRY, YOU send Postage.CANADIANS: Same as USA, NO Insurance on Air, Payable in US FUNDS, NO STAMPS, ADD$2.50 for your P. Check exchange rate, SAME FOR OTHER COUNTRIES: US Postal Servicenow requires a week for F/C, BK RATE 3-4 weeks, WE require 10 days to Process andDeliver. ORDERS OVER $30 FREE Bonus, Money -back -Guarantee on all items -15 days,ORDER ALL: Histor#cal.RPdio Services, Box 1537:0 Dept.Fl51,Lopg Peach, Ca. 90815, USA

The HORN SPEAKER..,.. 9820 Silver étesdo*r Drive. Dallas, Texas 771217 .3

to begin subecribing to your news-letter again. I collect phonographsand radio phonographs from 1925-35end need to have many of the magneticpick-ups rebuilt, and orthophonicVictrola reproducers repaired.Would greatly appreciate any helpfinding an expert that can repairthese properly.

Thank you,Ronald Callahan6002 Mentana St.New Carrollton MD 207811

Editor...check the classified ads.

Dear Jim:Enclosed find $5.50 check for an-

other years subscription.I think your magazine is pretty

good. May I make a suggestion?Could you have an article every

month or so on circuit and construct-ion details of some well known homebrew or kit set like Erla Reflex,Browning Drake, etc. I know they arein old magazines, but how many of uscan pay $5.00 or more for an old nag.even if we could locate one we want?

Also info. in Riders on some earlyradios is pretty meager. Some oldradios like Freed-Eisemann NR -5 andsome others don't even show types oftubes used, etc. Could you give morefactual info on some of these old"classics" and a photo of what theylook like?

I may be out of order on this be-cause I think you're already doingsome of this sort of thing.

Regards,Bill Irvine311 Hamilton St.Route 6Gulfport MS 39501

Editor...you are right. We aredoing some of this sort of thing,but not enough.

Dear Jim;Your air mail reminder of the ex-

piration of my subscription to "TheHorn Speaker" came a day or so ago.I will indeed be happy to renewonce again, and I would ask you topencil my subscription in. Regret-fully, I will have to ask you towait a few days for payment untilI or my wife can get to our tradingbank for the issue of a cheque inU. S. funds in your favour. Yousee, I am housebound at the momentwith my right leg in an elevatedposition (bandaged toe to groin)due to a blood clot I collected asthe result of a minor accident onsome stairs 21 weeks ago. Veryannoying and difficult to live with!

I have thoroughly enjoyed re-ceiving the magazine which hashelped to revive a lifetime ofmemories working in radio (+TV &HI FI etc.) a cycle not quite com-pleted yet, I hope.

Shortly you will receive a notefrom me advising a change of ad-dress. My wife & I have just had anew home built in which we hope tohave a few happy retirement years.

,,..1,41.14.41,...:.1.4,,,,,,,.

We should have been there monthsago but for delays and difficultieswith our builder. Hopefully thisphase will soon pass,

Up to the time of my accidentwe were commencing packing ourthings for the shift, and one ofthe big tasks to be undertaken hasbeen the packing in cartons, manyyears accumulation of various tech-nical books and magazines. Besidesthe more weighty tomes of Henney,Glasgow, Terman, Rider and others,there has been a considerablenumber of periodicals. These in-clude Radio News, Radio Craft,Shortwave Craft, Q.S.T., CQ, Wire-less World (U.K.) ElectronicsAustralia etc., particularly ofthe era 1930 - 1950. Some RadioNews go back to 1923 and bear con-tinual re -reading. A lot of thematerial which you place in "TheHorn Speaker" will undoubtedly re-veal itself to me when we resettleand I unpack the books.

It is my hope that I will be ableto catalogue them all before depart-ing this earthly scene! Because Ihate to think that such a goodsource of reference could be lostby those who will look after my es-tate, I have willed them all to ourlocal Museum of Transport and Tech-nology, (MDTAT) where hopefullythey will be kept for latter dayfolk who might be interested in theearlier days of radio. There are ofcourse New Zealand books which havebeen published over the years, andI have alongside me 3 or 4 which dateback to 1928, 1930, 1931, 1932, at atime when I was still at school andan interest in radio Was just awaken-ing within me. (Much to my fathersdisgust as he wanted me to be anarchitect!). In the 1930 issue ofthe "New Zealand Radio Handbook An-n.al" is a very interesting storyof the "Majestic" receiver, themake on which I cut my teeth. WhileI was still at school my fatherbought a Majestic 90, 14RF stages,power detector and push pull audioand mighty powerful and sensitiveit was. In those days it was pro-bably the most successful set onthe N. 2. market. I can still re-member the thrill we all had ofhearing Phil Harris at the CoconutGrove in Los Angeles and Bing Crosbysinging from KFI Los Angeles. In

those days reception of stationsfrom the U.S.A. was like receivinglocals today. KFI, KFOX, KMOI, WLW,KIICA to name just a few, were al-ways available. Not quite factualsometimes static did mar things abit! When WIW was on the very highpower of 500ff(W we would receive itin the daylight from mid -day toclose down (N.Z. time). And the"monkey gland transplant (for longerlife!) station, %EN, which went a-cross the American border used tocome in here like the proverbialload of ashcans. Today we no longerhear many U. S. stations on mediumwave and while I have some theories

often wonder the exact cause. My

log of U.S. stations received totals

close to 600 and added to thePacific and other areas we receivedtotals up towards 1000 stations.Alas, those days are long gone andwith my becoming a "ham" and anualif ied technician the emphasisshifted completely. Thinking backon it all I am sure that as youngpeople we had a lot more fun thanthose of today in respect of theradio world. We made our ownvariable condensers, rectifiers,coils, resistors, complete setsfrom crystal sets upwards ( on a

shoe string too - it was depressiontime.) - today how mach home build-ing of receivers goes on. Not much

I'd say. Why, my nephew aged 5carries around a delightful NationalPanasonic 8 transistor receiver(which Uncle Arthur has to repairwhen he breaks itl) Certain it isthat he and his generation will notknow the joys which we oldies hadwith early radios.

Well Jim, I don't want you tothink that I'm on a sorrowful nos-talgia kick, but just hope that theforegoing is of some interest toyou. Please keep up the good work.Don't forget to keep my issues a-side until my remittance arrives.You will be hearing from me againbefore too long.

With kind regards,Arthur E. Allen35 Fairlands Ave.Avondale, Auckland 7New Zealand

Editor...It is a good feeling torelive the fun of the past.

Club NewsNIAGARA FRONT1.í H WIRELESS

ASSOCIATION SUMMER MEETThe newly formed Niagara Frontier

Wireless Association is planning asummer meet to be held Aug. 13, 1977at the Old Amherst Colony Museum,500 Smith Rd., East Amherst, NewYork 111051. The activities willtake place between 11:00 AM and 5 PM.

The club is planning a programthat will appeal to both the col-lector and the historian. Therewill be a talk and a display onSpark Gap Transmitters by Ken Conrad.Art Albion will have a demonstrationon nickel plating to help you re-store those nickel plated items inyour collection. This will be fol-lowed by a panel question & answersession with the newer enthusiastin mind.

The club is also planning an oldequipment contest and a flea market.The museum is also arranging a "Tourof Williamsburg" program for theladies not interested in the wirelessprogram.

Everyone is welcome to attend,there is a $1 admission to coverthe museum's expenses. If you wouldlike further information just drop anote to Niagara Frontier Wireless

4 The HORN SPEAKER,,,,, 9820 Silver Meadow Drive, Dallas. Texas 75217

Assoc. in care of the museum (aboveaddress). We will send you a flyerwith the program and a map. Thiswould be a fine opportunity for youto see Niagara Falls and attend anAntique Radio Meet too.

IN THE GROOVEThe Michigan Antique Phonograph

Society has an official publicationcalled In The Groove which is ed-ited by 3olil1hitacre.

It contains news such as a largedisplay of antique phonographs atthe Grand Rapids Museum during Mayand June. John Perschbacher is re-sponsible for the display. The

Lansing Public Library on CapitolAvenue has provided exhibit spacefor the month of June. An addressfor the Society is: 2609 Devonshire,Lansing, Michigan 118910.

BUCKEYE ANTIQUE RADIO & PHONO-GRAPH COLLECTORS' CLUB OF OHIOThe next meeting is June 19 at

the home of Don Gfell, 530 NeedhamAve., Kent, Ohio 44240, 216 673-6487. This is also our annualpicnic. Everybody is welcomed foran enjoyable day. The mein courseis hamburgers and hot dogs. Pleasebring side dishes to compliment themain course and every body is re-quested to bring their own placesetting. We could also use a fewextra grills, chairs and tables.Also bring items for show, sale,and other items of interest. Inorder to promote the growth of ourclub, please try to attend thescheduled meetings::

"ACE" Apparatus

Type AVB Regenerative Tuner150-475 Meters. Price $32.00

- Type ATC Detector Cabinet.Price $12.00

Type AVA Regenerative Tuner175-475 Meters. Price $45.00

Type AVC Short Wave Regenerativereceiver, 175-475 Meters, Price, $56.00

Type TTR Regenerative Receiver -150-300oMeters. Price $75.00

A-2 Two -Stage AmplifierPrice $40.00

COLUMBIACHAMPION

1906

Al -R-$59.00This instrument (MagnavoxCombination Set) consists ofMagnavox electro -dynamicReproducer combined with aMagnavox Power Amplifier inone unit.

Disc Graphophones

Type BH$30.00

1924 ad

THE illustration at left shows the interior con-struction of the Magnavox electro -dynamic Radio

Reproducer, a type representing the greatest advanceever made in radio reproducing equipment.

The diaphragm (shown above) is of special inter-est, as explained in the body of this advertisement.

MAGNA VOX-The true Radio Reproducer

THE basis of the operation of a Magnavox Repro-ducer is its diaphragm, the importance of which can

be seen from the fact that it is required to render analmost human service in recreating every tone andquality of instrumental music as well as speech.

This diaphragm (as illustrated above) has been de-signed and constructed in accordance with entirely newprinciples. Its shape, size and special character make itcapable of responding to the widest range of tones.

But even this highly efficient diaphragm might behandicapped by operating restrictions-every diaphragmmust have a vibrating force applied to it, and the inher-ent ability of any diaphragm will be injured if it is affect-ed by mechanical operation or other foreign influences.

The use of the electro -dynamic principle of oper-ation (found only in Magnavox Reproducers) removesall objectionable influences. This principle, utilizing thefamous"movable coil" permits the Magnavox diaphragmto respond in perfect unison to the original tone.

There is a Magnavox for every receiving set: Type Rfor storage battery sets, and M1 for dry battery sets.

THE MAGNAVOX COMPANYOakland, California

New York Office: 370 SEVENTH AVENUEPERKINS ELECTRIC LIMITED, Canadian Distributors

Toronto, Montreal, Winnipeg

Radio News for November, 1921 3R

The HORN SPEAKER 9820 Silver Meadow Drive, Dallas, Texas 752175

I WANTTO GO !

Co

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LFORUMS

CONTESTS

SWAPFEST AND TRADES

EXHIBITS AND BOOTHS

BANQUET AND SPEAKERS

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AND THE BIGGEST SVRPS AUCTION YETI

FOR A PRE -REGISTRATION PACKET AND ACHANCE AT THE GRAND PRIZE WRITE:

CONVENTION ?7P.O. BOX 19406DALLAS, TEXAS 75219

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ELIGIBLE FOR THE DRAWINGS.

9?dh we1'»Waye eWadic and YhdrtairaM Yociely

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The HORN SPEAKER 9820 Silver Meadow Drive, Dallas, Texas 75217

TELEVISION RECEIVER

The Western Television Receiver.

THE Western Television Corp. presentsa new television receiver, incorporating

two sets-one for the reception of pic-tures and the other for the accompany-ing sound transmitted in the broadcastband. A modernistic cabinet, shownabove, together with a neat ground -glassscreen are attractive features.

RADIO -CRAFTfor AUGUST, 1932

RADIO NEWS FOB SEPTEMBER, 1932

Personal interviewswith broadcast artists

and executives

BySamuel Kaufman

RAY PERKINS, one of radio's mostversatile entertainers, recentlylaunched a new NBC series of novelty

programs heard Tuesdays and Thursdaysunder the sponsorship of the Barbasol Com-pany. His programs consist of songs, musicand, humorous chatter. He is supported byPeter van Steeden's Orchestra. Song -writer,singer, pianist and comedian, Perkins hasoften been referred to as the "one-man radioshow." Half of the songs he sings on theair are his own and many of them have notbeen published. Since he first started toentertain at the age of six, Perkins haswritten musical shows, appeared in vaude-ville, made pictures in Hollywood andworked for a magazine, in addition tohis successful radioventures. This pro-gram brings Perkinsunder the samesponsorship as Sing -in' Sam, of theCBS, and the OldSingin' Master ofthe NBC.

EN BERNIE-I) the CBS "OldMaestro"-was bornBenjamin Ancel, theson of a blacksmithwho lived in theshadow of Brook-lyn Bridge. YoungBenjamin took to music at anand at fifteen, it is said wasstructor at a New York music school.His next step was to the duties ofviolin demonstrator in a New York depart-ment store. Given to wisecracks, even atthat early date, Ben always amused on-lookers. A theatrical magnate happenedalong one day and Ben found himself invaudeville as one-half of the team of Bernieand Klass. Ben's act was designed alongmusical lines until he teamed with PhilBaker. The Bernie -Baker vaudeville teamwent in for comedy, the pay checks in-creased and the act became an accepted hit.

BEN BER

RADIO NEWS FOR JULY, 1931

The Chemist's Role

Gaseous rectifiers are developed in the chemicallaboratory at the hands of skilled chemists, aidedby expert glassblowers. Complete pumping equip-ment, tanks with different gases, electrical testinginstruments and other apparatus aid the designerof such devices in carrying out the work. Inalmost every branch of radio the unassuming chem-

ical laboratory plays a vital role

There are ten thousand different grades of paperavailable for loud speaker diaphragms, compli-cating the manufacturer's problems. Here is Bur-tex, an impregnated cloth cone, which is a triumph

of the chemist

T may seem a far cry from the wonderful re-production of a radio program in the de-lightful atmosphere of the modern living -room to the test tubes and beakers and vile

smells of the chemical laboratory. Yet the two are closelyknitted together as the practical basis of the present radioindustry.

At every turn in the design and production of radio equip-ment there are chemical problems to be solved. In fact. thechemist today plays an ever-increasing role in the productionof radio sets, accessories and parts, so that the larger radiomanufacturing organizations are just as insistent on havingthe necessary chemical direction in their efforts as they are onhaving the best electrical and radio talent. From the radiovacuum tubes; based on electronic emission from speciallycoated filament wires, to impregnating compounds for con-densers and sealed -in assemblies, and again to short-wave trans-mitters with extremely high -frequency conductorsto be insu-lated, the chemist is.called upon at every turn to pass judg-ment on the chemical aspects of the case. And so radio is achemist's field, just as it is that of the electrical engineer,mechanical engineer, metallurgist and other technicians, quitein addition to being the supposed exclusive field of the radioengineer.

p'-'--- :he greatest work of the chemist in the field of

split up several yearsaker remain steadfast

,<,enas--each one now a star in his ownright. Ben was seized with the idea of anovelty band with the conductor doingsomething besides waving a baton. The ideaclicked from the start and Bernie found him-self and his band vaudeville headliners. Hewas booked at the Roosevelt Hotel in NewYork for five years. London and Hollywoodsuccesses followed before the band began along Chicago booking. His broadcasts fromthe Windy City over coast -to -coast Colum-bia hook-ups have brought him addedlaurels.

111 iZADIOMost of us think of radio problems as nutsfor the electrical or radio engineers tocrack. But chemistry is playing a surpris-ingly important part behind the scene., inradio development, as this article discloses

By Austin Lescarboura

radio is in connection with insulating problem. Here we aredealing not altogether with high potentials, which necessitateconsiderable electrical strength for the insulators in the case oftransmitting practice, but also with radio -frequency losses thatcome about in radio receivers handling weak radio -frequencyenergy, and particularly in short-wave transmitters handlingpowerful radio -frequency energy.

Originally, hard rubber was thefavorite material for radio insula-tion purposes. In recent years,however, the trend has been awayfrom hard rubber, as chemists havefound new materials. Bakelite, aswell as other synthetic resinouscompounds, has played a very im-portant role in radio, and there ismore bakelite being used in radiotoday than any other insulatingmaterial. Here the chemists havesought to produce various gradesand kinds of bakelite, to meet spe-cific requirements ranging all theway from simple mechanical con-siderations, perhaps involving beau-tiful moulding, to certain high -fre-quency insulation problems.

Interesting developments havebeen made in the field of syntheticceramics, or ceramics made of purechemical ingredients, mixed underlaboratory supervision. Such newmaterials as Isolantite and Crolitehave played a very important role

in radio-in fact, they may be said to be essentially radiomaterials, since in no other electrical applications are theirexcellent insulating properties so fully appreciated. Chemists,specializing in these materials, have been able to develop allmanner of special materials, differing slightly one from theother, so as to meet specific requirements. Thus in the case ofhigh -frequency circuits, the aim has been to reduce the phaseangle difference to a minimum, even exceeding that of hard rubberheretofore considered the standard of excellence. In the caseof transmitting tubes, the aim has been to produce a materialcapable of withstanding severe heat with maximum insulation,together with the severe shock of rapid heating and cooling.

Both Isolantite and Crolite have their origin in a fine powderwhich is treated with a gas catalyst and pressed into variousforms. These may be billets, which are machined to finalshape in subsequent operations; extruded rods and tubes, whichare cut to length and machined if necessary; and flat slabs orsheets. The roughly formed parts are dried, and then placed

DESPITE America's broadcasting suprem-acy, the field of radio drama has been

badly neglected by domestic stations. TheB.B.C., we discovered on our recent Londonvisit, gives far more time and care to thisimportant division of broadcasting than doeseither of the two American networks. But,of late, we have noticed some increased ef-forts on the part of NBC and CBS to ad-vance radio drama. The NBC's Radio Guild,under the direction of Vernon Radcliffe, hasmade some worthy efforts, although manyprograms have been devoted to adaptationsof stage plays rather than the presentationof original radio scripts. The CBS recently

inaugurated a series of half-hour experi-mental dramas, under the direction of DonClark, continuity chief. The series, accord-ing to Mr. Clark, was designed to provethat mature radio drama can be producedto hold and intrigue an audience for halfan hour.

LWELL THOMAS, noted author, travelerand news broadcaster, has signed a long

time contract with his new sponsors, theSun Oil Company, which presents him dailyover the NBC. The author of a score ofbooks and a lecturer who has appeared in

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1977

MART The HORN SPEAKER..... 9820 Silver Meadow Drive, Dallas, Texas 75217

Classified ad rate: 6¢ per word.Photo ads: $2.00 extra.

Deadline: 20th of the preceding month.

"RADIO AGE" a radio magazine de-voted to wireless and early broad-cast eras. Contains interestingarticles written by collectors,articles published in early radiomagazines, lots of reprints offamous radio ads, and a classifiedsection for buying or selling radioand electronic items. Subscribe at$7.50 per year for ten issues.;fail check or money order to RadioAge, 1220 Meigs Street, Augusta,Georgia 309014.

FOR SALE OR TRADEFOR SALE: 1918 Duck Catalog (#11),professional reprint, 240 pages withhundreds of illustrations. A goldmine of information on pre -1920 wire-less equipment. Each article for saleis throughly explained by the catalog.Many bread board loose coupler. re-ceiver/spark gap transmitters shownwith schematics and parts lists.Excellent quality, satisfactionguaranteed, $7.00 post paid (bookrate). Dick & Ann Schamberger,1975 Hertel Ave., Buffalo N.Y. 114214.Also available: Operators manuals andcatalogs for Federal telephone andtelegraph receivers, SASE for details.

FOR SALE: 3 AK Breadboards, excel-lent $300. each. Kennedy XV º225.Marconi Model 55 Fortable X55.Grebe CR -12 $325. Send SASE forlist. Paul Giganti, 2429 San CarlosAve., San Carlos CA 94070.Phone: 415 593-4723.

BLANK BAKELITE PANELS - Cut to size.1/16" to 3/8" thick. Fabricatingand engraving services available.SASE for pricing sheet.Parsons, WB1BV0, 22 Forest St.,Branford CT 06405.

WD11 Adaptors, use UX199, 120, VT2Ii.No wiring changes, Radiola III'sbattery hook-up ir;luded $5.25 pp,2 for X9.25 Keith Parry, 17557Horace St.: Gr .ada Hills CA 91344.

WD11A--$10.--uses old style 864.WD11B--$10.--uses new style 864(now-microphonic)

WD11R--$10.--uses low filament cur-rent tube.ABOVE three tubes are mounted onnew style WD11 Base.X99R or X2OR 15. V99R or V2OR $7.RADIOLA BATTERY SET SERVICEMANUAL 1922-27--$5 35 pages,covers ten Radiolas not coveredin Riders.A FREE copy to the first one whosends a post card offering to senda "Riders Vol. 16 to 23 index," tobe copied and returned.Needed Riders Radio Vols. 20, 21,23. Will pay $10. each or tradeany of above items, or Riders TV

FOR SALE OR TRADEone to twelve or Riders Radio 3,14, 8, 10, 11, 13, 14, 15.Ken Hanson, 3403 E. Broadway,Long Beach CA 90803.

FOR SALE: Have quantity of Victor,Columbia, Cheney, Sonora, Edison andothers in both table and uprightmodel Victrolas. All in excellentworking order. Also have restoredearly 1930's Radios in both Cathedraland Console models. Same batteryradios. Send SASE for list. Will dorestoration work for anyone desiringsame. Philip Guinan, Route 1, PageRoad, Hudson N.H. 03051.Phone: 603 883-8586.

WE ARE COMPILING a catalogue of earlyday radio test equipment. Pictures,catalogues and literature of thisearly day radio test equipment isneeded. Give particulars and pricein first correspondence. Wm. L.Poston, 3212 Peach Tree Ct.,Bakersfield CA 93301.

FOR SALE: A. K, 165 Cath., worksgood, needs refinishing $85.U. S. Gloritone 99A Cath. touchyvolume $65.

Splitdorf R-500 with matching horn,not checked, no tubes 185.10` shipping.WANTED: WD11 tubes. Ross Mason,641 So. Georgia, Mason City, Iowa50401. Phone 515 123-4687.

FOR SALE: Zenith 3R receiver, #565,4 tube, with a Music Master RadioReproducer horn speaker. Tubes andbattery clamps. Tom Flanders,1125 W. 127th Street, Apt. 7-W,Alsip, Illinois 60658.

FOR SALE: Crosley Trirdyn x,38;Metrodyne »23; Radiola 100 speaker$12; Rola speaker (20; plus shippingAlso earphones, tubes. SASE toArthur Harrison, 1021 Falcon Drive,°)lumbia MO 65201.

ING battery radios, speakers,paper, early test equipment, recordcollection, other. Large SASE forlists; state categories of interest.R. W. Claude, 54 Dublin Ave., NashuaNH 03060 or 1-603 889-42511 on Tues-days 9 p.m. to 11 p.m. EST.

FOR SALE OR TRADE: Large list ofearly radios and equipment avail-able for large SASE with 240postage. Glenn Streeter, 26008Crenshaw Blvd., í106D, TorranceCalifornia 90505.

FOR SALE: Send large SASE plus26 cents postage for latest listof radios, tubes and literature.Richard Wolven, 2614 Reno Road,Castleton N.Y. 12033.

FOR SALE: Early model RCA portablemixer; aluminum case, X20.00.C. D. Houston, Jr., 3960 ThreeMile Drive, Detroit, Michigan 48224.313 TU2-1836.

FOR SALE: Victrola Credenza #2508spring drive. Good -excellent, tooheavy to ship P150.00. H. Balmer,

610N 14, Marysville KS 66508.

11

FOR SALE OR TRADEXEROX AWA OTB'S, same format,stapled, 7-1 through 9-14, $12. One

group Xerox Modern Electrice, 12issues 1910-121 300 9x111 pages, $20.(under my cost). Original ModernElectrics 9/12, waterstained, $10.Postpaid. Alan Douglas, Box 225,Pocasset MA 02559.

FOR SALE OR TRADE: Westinghouse RA -DA,Pilot TV, Freshman Masterpiece withbuilt in horn, David Grimes 6 tubein fancy cabinet, Trinity 2-T-6 infancy cabinet, and more. SASE.Richard Cane, 8391 NW 21st. St.,Sunrise Fl 33322.

EDISON COLUMBIA cylinder records.Always in stocks New showroom withmuseum. Phonograph repairs ourspecialty. Send us your want listwith SASE, Olden Year MusicalMuseum, Dept. 6, 2/08 JubileeTrail, Arlington TX 76014.

FOR SALE: Early battery and AC radios,speakers, phones, parts,miscellaneous,new speaker cords $2.00 each. LargeSASE for lists.

WANTED: Base with driver for AK "L"horn, RCA III A panel. Franklin Haas,207 West 30th., Hutchinson, Kansas67501.

HAVE SCARCE OLD RADIO - TV tubes.Also some old radios. SASE forprices. Harold's Radio, 3106 N.3rd., 17110.

WANTEDWANTED TO BUY: Test equipment fromthe 20s and 30s mint condition pre-ferable. Give complete discription,condition and price prepaid and in-

, sured in first correspondence.Picture will be helpful. Wm. L.Poston, 3212 Peach Tree Ct.,Bakersfield CA 93302.

WANTED: Any radio fan magazines.Also, any radio magazine with com-mercial broadcast or star informat-ion. Examples --"Radio Guide, RadioStars, Radio -TV Mirror,"etc. Also"Photoplay" magazines. 1 or a 100.

Fred L. Davis, 5106 Sk_ip2Y Street,Memphis, Tennessee 38116.

WANTED: Scott, McMurdo Silver, Lincoln,and other classic receivers. Also pre -

1930 battery sets, speakers, mikes,etc. J. E. Cunningham, 23W 675Ardmore, Roselle IL 60172.

WANTED: Pre -19110 TVs also will pay$100. for restorable Pilot TV -37.Bill Russell, 64631 Fulton, VanNuys CA 9]J.LO1.

WANTED: Kellogg tubes, radios usingKellogg tubes, anything! Also,Breadboard variometer vernier dialplates. Rosenthal, 507 S. MarylandAve., Wilmington, Delaware 19804.

WANTED: Adams -Morgan RA -6 receiver.Cash or trade. Hoffman, 2570 FalconStreet, E. Meadow N.Y. 11551.

10 The HORN SPEAEEIt..... 0820 Sfher Irtedow Drive. Dallas. Texas ?S217

Wonderfully Perfected

RTS STANDARDDetector Panel

RES

Price

$5.95without

tube

Prepaid byInsured

Parcel Post

Install this efficient R.T.S. Panel andyou possess a correctly designed DetectorPanel capable of producing signal strengthunequalled by any other tested in ourlaboratory. It is guaranteed.

Write for Circular

RADIO TESTING STATIONDept. 4, 25 Sturges SL

Binghamton, New York

COLUMBIASTERLING

JI

1906

COLUMBIAMAJESTIC

1921 ad 1921 ad

.

. \.... \ \ \ \.; ;\\\\\\\\\\\°-,\;\` ;\\\\\\\\\., ., , , ..S

a_\- 1 -\. w: \ : _ \\ ; \

THE A -P VTAMPLIFIER -OSCILLATOR

-the amplifier usedby the U. S. Navy."Use the tube theNavy uses."

Price $6.50

NOTEN E WLOW

PRICESA -P Tubes are licensed bythe Radio Corporation ofAmerica under the DeForestAudion and Fleming patentsfor (amateur and experi-mental use in Radio com-munication.

In addition to being nationaldistributors for the Moor-head Laboratories, Inc.Mfrs. of A -P Tubes, the At-lantic Pacific Radio SupplyCompany are also exclusivePacific Coast distributors forthe following companies andproducts:-Shaw InsulatorCo., Mfrs. of moulded equip-ment, DeForest Radio Tel.& Tel. Co., Mfrs. of radioequipment, Diamond StateFibre Co., Mfrs. of Con-deenaito-Celoron, RedmanolChemical Products Co.,Mfrs. of insulating varnishesand lacquers.

THE A -PELECTRON

RELAY-the most sensitivedetector of spark sig-nals known to theradio -art.

Price $5.00

AT_YOUR_DEALER OR DIRECTIFROM

ATLANTIC PACIFIC RADIO SUPPLIES CO.HENRY M. SHAW, Pr.sident

638 Mission St, San Francisco, Carferia

PAUL F.GODLEY

selects A -P Tubes forsupreme English test.

He wires:-"A-P Tubes selected as most satisfactoryon American market for use in multistage amplifiersbecause of their low capacity and low current con-sumption."

The A. R. R. L. is sending Paul F. Godley, ofMontclair, New Jersey, to England to receive mes-sages from American amateurs. Because the effi-ciency of multistage radio frequency and audio fre-quency amplification depends entirely upon the tubesused in his multistage amplifiers, he has chosen A -PTubes exclusively for this purpose. The A -P Am-plifier Tube is the tube used by the United StatesNavy, the famous Navy Type S.E.-1444.

"Use the tube Paul F. Godley has selected." "Usethe tube the A. R. R. L. will use in the supremetest." "Use the tube the Navy uses." "Use A -PTubes for efficiency."

At your dealer or direct from the factory. Note thenew low prices and order now.

Disc Graphophortes

Type BI$45.00

Disc Graphophones

Type BD$100.00

Hole all waythrough

1977 ad

INSTRUCTION CARD IC -86968

INSTRUCTIONS FOR INSTALLING ANDOPERATING AG -814 RADIOLA LOOP ANTENNA

Hole onlypart waythrough

Glans ball goes here

D 1 C BC

I T

f:7 G

Startwinding

hereo

Fig. 1The loop is made with the following parts:

1 center piece A 4 long dowels E2 base pieces F1 shaft G1 glass ball

1 center piece B8 short dowels C4 semi -circles D

1 coil of wire (113 feet long)

Fig. 2

Endwinding

here

i

For Sale; RCA AG -814 Loop repro. Kit incl;Woven brown braid covered wire,Ltched brasname plate.1924 Inst. card,:':anogariy frame.k50.F0B USA. Satifaction or refund.Antennawire avail. 11.00 for card & wire sample.Glenn Streeter,26008 Crensnaw blvd. #106D,Torrance, Califoria, 90505 (213)541-3279.

i

The HORN SPEAKER.- 9820 Silver Meadow Drive, Dalas, Texas 75217 9

SYMBOLS ADAPTEDDY LR.E

OTHER SYMBOLS NAME

__

VARIABLE CUING

A INDUCTION COUPLING OR AIR CORE

TRANSFORMER

AUTO -TRANSFORMER

AIWIRON CORE TRANSFORMER

AMMETER-OAVOLTMETER-O

WIRES CROSSED JOINED

WIRES CROSSED NOT JOINED-L -F- ANTENNA

GROUND

--65-- TELEPHONE RECEIVER

COIL OR LOOP ANTENNA

LOUD 50020106 TELEPHONE RECEIVER

(() r THREE ELECTRODE VACUUM TUBE

1923

SYMBOLS ADAPTEDDV I.R.E.

OTHER SYMBOLS NAME

HIppJlIiII-- BATTERY

SINGLE CELL-----I1--

--CO-Ir- DIRECT CIRRI' GENERATOR

__,(5_ - MIERIIAINIG CORRENI GFNEMIOR

- RESISTANCE (NON INDUCTIVE)

W VARIABLE RESISTANCE OR RHEOSTAT

CONDENSER FOR AUDIO FREQUENCIES---11-CONDENSER FOR RADIO FREQUENCIES

--IV--

II ,NE VARIABLE CONDENSER en DOT ISON R01ATO1RA1E)

/ 11

-3.10017 INDUCTANCE

)---"l1 IRON CORED INDUCTANCE

p pr-- r VARIABLE INDUCTANCE OR VARIOMETER

E

/O¡G ¡(J

Z/51LV) INDUCTANCE VARIABLE BY TAPS.

I- CRYSTAL DETECTOR

COMMON SYMBOLS USED IN RADIO CIRCUITS

Try This Perfected LoopAT OUR EXPENSE

Selective, directional. Reduces reradiation andinterference. Extremely compact. Entirely en-closed by Bakelite shields. Send a postal, specify-ing the type you want to try. The money youpay the postman may be refunded anytime dunng the to days you try it out.Keep it only if it satisfies. Write thepostal NOW ! !

Type -A-737 0700nal meters) 6 inches square-nom$10.

Type -A-7238 (075 -tono meters) 6 inches square-non-directional _ $12.

Type -B-2537 750 meters) :8 inches square-direc-tionalfA20.Type -EL -2520 (ºoo-r8,o0o meten) with honeycomb coil

mounting. 18 inches square-directional $25.SEND FOR BULLETIN X-702

V=DEtl t .

RJMPG. CO., Dep , ASBURY PARK, N. .

1924 ad

M. LÍON DELOY, OF NICE, FRANCEWho was the first French amateur radio telegrapher to attain two way communicationwith American amateurs.

Occurrence: last months of 1923 Source: Radio Broadcast, 1924, p. 123.

1924 ad

^ O2151,-,=---y - _d" 7oc i 1E \\\," - / n i% _

,ly,iWOOD'SThe Thing!/

MUSIC MASTER is equipped witha wood amplifying bell. Wood, pro-perly shaped as a horn,- furnished onlywith MUSIC MASTER,-is the onematerial that makes possible perfectreproduction of the actual. living tonesthemselves.

Go to your radio dealer and ask tohear MUSIC MASTER. Its clarity,brillance and naturalness of tone willdelight you-and prove to you thatMUSIC MASTER is more than a

name.DEALERS EVERYWHERE

14" Model forthe Home, $3021" Model forConcerts, $35

Comes complete,ready to attachin place of head-phones. No ad-justments. Nobatteries required

MUSIC MASTER CORPORATION(Formerly General Radio Corporation)

Makers and Distributors of High -Grade Radio Apparatus

CHICAGO S.W. Cor. 10th and Cherry Sts., PHILADELPHIA PITTSBURGH

aH. 11.0St *

API,O: REPRODUCERh TilEl'EIE;FI

8 The HORN SPEAKER 9820 Silver Meadnw Drive, Dallas, Texas 75217

Radio News for d ugust, 1925

Resonant \Vood InsuresNatural Tone Quality

MODEL V1 $O14" Wood Bell

MODEL VII $3521" Wood Bell

(Prices of dl models slightlyhigher in Canada)

CanadianPricesSlightlyHigher

Six Models$60 to $400Guaranteed

Unconditionally

1925 ad

-evolutionA series of receivers designed toprovide powers of radio receptionequal to the capacities of MusicMaster Reproducer.

The Musical Instrument of Radio-there IS no substitute

Type 215Six -Tube Special Music MasterCircuit. Built-in Music MasterReproducer. Very selective, longrange, and splendid tone quality.Solid mahogany cabinet inbrown mahogany art sain finish.

Price $215

T LAST -radio reception incorporating the demon-strated results of latest radio research, and combining

in one superb radio ensemble the proved principles ofMusic Master Radio Reproduction.Audition will prove MUSIC MASTER'S outstanding powersof long range and high selectivity, its clarity and volume,and above all, its supreme Tone Quality based on MusicMASTER Reproducer as a vital element of the ensemble.

Sold by authorized distributors and by Registered Dealers everywhere.Call on your MUSIC MASTER dealer-today. See MUSIC MASTER

-hear-compare-before you buy ANY radio set.

C (?usic master CorporationMakers and Distributors of High -Grade Radio Apparatus

128-130 N. Tenth StreetChicago New York PHILADELPHIA Pittsburgh Montreal

Canadian Factory: Kitchener, Ontario

RADIO

1921 ad

Yi OItro.G

yi

rAPPARATUS

and SUPPLIESROSE RADIO SUPPLY604 Gravter St.. NewOrleana. La.Send loe for Latest CataIo

aMerchants of standing de-sirous of profiting byMusic Master prestigeand reputation are invitedto communicate with

Music MasterCorporation

PRODUCTSPart of 1921 ad

1977 ad

Now Available!

womK)IU

STEREO

Here's your secondedition of the1877-1959 phonoclassic, now exten-ded to 1976.

Discover the story of recorded music in30 fascinating chapters. Enjoy photos ofexotic music machines from early cylinderphonographs to stereo. Own THE refer-ence for phonograph enthusiasts. 519.95hardcover, $9.95 soft.

SILVER GHOSTS: 76 beautiful pages ofScott radios, from the earliest 1940's.Puett's classic with pictures, old ads anddiagrams. $10.00.

VINTAGE RADIO, 1887-1929: Pictorialtory of pioneer days, 1,000 photos, 263pages. $10.95 hard -cover, $8.95 soft.

A FLICK OF THE SWITCH, 1930-50:Fun picture reference of home, military,lam, professional radio -TV -electronics,

,.12 pages. $10.95 hard -cover, $8.95 soft.RADIO ENCYCLOPEDIA, Gernsback's1927 classic beautifully recreated, 175pages. $14.95 hard -cover.

RADIO COLLECTOR'S GUIDE, 1921-32:Data book with 50,000 facts on 9,000models by 1,100 makers, 264 pages, $6.95.1926-38 RADIO DIAGRAMS: Beitman'sclassic of 600 models, 240 pages, $7.00.

CIRCUIT DIAGRAMS for any pre -1951radio, just $3.50. Send model number.

SEND TODAY to Vintage Radio, Dept D,Box 2045, Palos Verdes, Ca. 90274.We pay postage. Calif. residents add 6%.

Name

Street

City St ZipFREE! Age Guide with each order. FREE!

TOTAL S

You'll Enjoy It!

G. M. PROUDFOOTDETECTOR AND TWO-STEP

AMPLIFIER

Highest Quality Lowest Prices

Detector and One -Stage Amplifier$25.00

is duplicate of above only one unit less.

The HORN SPEAKER...., 9820 Silver Meadow Drive. Dallase Texas 75217 7

RADIO NEWS FOR JULY, 1931

Huge impregnating vats employed in the production of paper con-densers, one of the many contributions of the chemical laboratoryin condenser manufacture. At the right is C. G. Smith, inventorof the Raytheon gaseous rectifier and an outstanding authority in

the field of gaseous conduction and rectification. He has specializedin gaseous phenomena for many years

in saggers and fired in a gas -heated furnace. After firing the partsare rock -hard, with remarkable mechanical, thermal, electrical andchemical properties.

Imagine an insulator which can be heated to incandescence,plunged into cold oil or water, again heated and plunged, overand over again many dozen times, without developing cracks orbreaks. That is one of the achievements of the chemists workingon these radio insulating materials. Imagine, it you will, a minutetube, about the size of an automatic pencil lead, containing twotiny parallel holes, 11/z thousands of an inch in diameter! Thatis what these chemists have produced for the heater type vacuumtube.

Special forms of glass have been developed, with remarkableinsulating properties particularly at the higher frequencies. Pyrexhas found many important applications in radio. Many of theshort-wave antennas used in transoceanic radio work are Pyrex -insulated.

The extremely high frequencies used in very short-wave radiohave caused no end of research into better insulating materials.Certain compounds of mica and binders have been developed, suchas Micalex, which have proved excellent for the purpose.

There are still endless insulation problems in radio. Aside fromthose already mentioned, many skilled chemists are engaged indeveloping suitable enamel insulation for wire ranging from No.14, which is fairly heavy, down to wire half the diameter of humanhair. There are many problems involved in good enamel insula-tion, not only electrical strength but also ready application; flexi-bility, so as not to crack when bent, and so on.

Impregnating CompoundsClosely allied to insulating problems are the impregnating com-

pounds. These serve to insulate, but must possess additional fea-tures such as sufficiently low melting point, so as not to heat theembedded components unduly; freedom from chemical actionwith the imbedded components; sufficient mechanical strength,permanency and so on.

The story is told in the radio industry how a certain form ofsuperheterodyne assembly, representing the very heart cf a re-markable radio receiver, had to be virtually embalmed in impreg-nating compound as protection against position displacement,moisture and so on. The task seemed simple enough to manu-facturers accustomed to impregnating electrical windings. Hencethe same treatment was given to the superheterodyne assembly.known as the "catacomb" because of the maze of wires. However.for some unknown reason, the catacombs did not stand up. They"went bad" in short order.

practically all English-speaking parts of theworld, Thomas was widely known as a re-porter and traveler before he entered radioin 1930. He was born in a Colorado min-ing town and while still in his early twentiesled two expeditions into the Arctic. Sincethen his explorations have included exten-sive tours into Malaya, Upper Burma andCentral Asia. Thomas was the man whogave the world its first account of ColonelT. E. Lawrence, the mystery man of Arabia.He was one of the first correspondents toenter Germany after the signing of thearmistice. On the new sponsored programseries, Thomas comments on news events inmuch the same manner as on his old LiteraryDigest - series.

xl

Did YOU EverStop to Think ?&That the chemist has had al-most as much to do with per-fection of the radio as has theelectrical and radio engineer?

QThat every single new devel-opment requires some contri-bution from the chemical Lab-oratory?

&That without the chemist'scontribution of improved mate-rials the vacuum tube would helittle beyond the state of devel-opment it had attained in 1910?

A chemist was set to work, and he soon discovered certainchemical action between the compound and certain metalparts imbedded therein. Because the impregnating com-pound was ideal in every other respect. the chemist workedout the solution in the form of a certain lacquer protectivecoating for the metal parts causing the trouble. The cata-combs thereafter were entirely satisfactory.

Much audio transformer trouble has been traced to im-pregnating compounds. The wire in the secondary windingof the usual audio transformer is exceedingly fine and itdoes not take much corrosion to destroy the winding. Hencethe chemist has been enlisted in this work. so as to providetransformers that really last.

A Study in Rare AlloysMuch of the present-day radio work falls in the class of

metallurgy, which is perhaps just (Continued on page 75)

SUPERScreenGrid

E4911Comp§ et.1... tube.

rRV 1T30 DAYS FREE

BEFORE YOU BUYFaaorytoyoo..Satoto50%. ("datesSwan Grid Electric or BatteryRadio. Get 'Send No H oney' OBw.

RadioAmazing bargains direct frombig, old reliable factory. Don'tbuy unless 30 days' use provesentire outfit unbeatable at up totwice our price for tone, seler-

.tvtAe.uoJtivity.distance,power. 1 yr. guar.

SPIICIALcabinets FREE! OPP=Sand No obligation.MidwestrtRasd1oo Corporation

001 -DJ. Mine. §7 pt.. Ciselo.atl, Obis

Both ads: July 1931

The ROOSEVELTSuper -Heterodyne

Uses new Pentode powertubes in push-pull. also

new type variable -muscreen grid. 9 tubesin all. to KC. sepa-ration. wonderfultone and distance.The most perfect ra-dio ever built.

New CUBMidget

Uses new Pentodeewer tube and vari-able -mu screen grid.Fine tone. selectivityand distance. Coa-plete with tubes.$49.75.

COMMONWEALTH RADIO MFG. CO.1157 W. Harebell It.. Cable: RADCOM. CHICAGO

next door to strictly chemistry. In the de-velopment of audio transformers, it hasbeen necessary to develop alloys of de-sirable magnetic characteristics. Fromcommon grades of iron, in laminatedform, radio manufacturers have gone tosilicon iron, nickel iron, and other alloys,some of them quite costly, in quest of de-sirable characteristics so as to providetrue tone response over the entire musicalfrequency scale. Certain patent consider-ations, particularly covering nickel steel,have caused some transformer manufac-turers to search and search for suitablealloys that might circumvent the patents.A remarkable opportunity has been offeredto the metallurgist in this field.

Even in the familiar dynamic loudspeaker, metallurgy plays an importantpart. The grade of iron used for the coreof the electromagnet is most important,for it determines just how much magneticflux shall be obtained from a given bulk ofiron, and this bulk, in turn, determinesjust how efficient the loud speaker shallbe. The less the bulk for a given fluxdensity, the better the loud speaker.

The Chemist and Vacuum Tubes

Consider the vacuum tube. To thelayman, it is simply a piece of wire calledthe filament, which is heated by means ofcurrent; a lattice member, called the grid,which handles the control energy; a cylin-der, called the plate, which handles theoutput energy; and a glass envelope toprovide a means of placing these elementsin a good vacuum. Simple enough. Yetthere is a world of chemistry involved inthe vacuum tube-a sad truth whichvacuum tube manufacturers have learned.

First of all, there is the filament. Thetrend today is decidedly towards theoxide -coated filament, and away from thetungsten and thoriated tungsten types,thereby multiplying the chemical prob-lems just about a thousand times. Spe-cial alloys are being sought for the wire,and, in many instances, found by chemistsspecializing in vacuum tube problems.Nickel, heretofore used mainly for fila-ment, is being abandoned, because of itschemical interaction with the carbonatesused as the coating. In fact, it was achemist who first told vacuum tube man-ufacturers why certain low -current types"went west" after a few hours of use.

Oxide -coated filaments require manythings. First, there must be the wire,chemically immune to the carbonateseven at high temperature. The wire mustoffer the necessary high electrical resis-tance. so as to be economical in operation.The best wires are those with a cold re-sistance several times that of nickel, andwith the resistance rising rapidly as theywarm up, so as to provide some measureof automatic current regulation. Thewire must not stretch unduly when heated,to sag and "short" with the near -by grid.A high melting point is necessary, for thecarbonates require about 750 deg. C. toprovide the necessary emission.

And then there is the oxide coating,usually made up of strontium and bariumcarbonates, prepared with utmost careand then applied to the wire by meansof successive dippings and bakings in acontinuous operation, and by means ofan air brush in the case of the a.c. heatercathodes. Utmost precautions are takento guard against impurities in the oxidecoating. The larger vacuum tube manu-facturers maintain chemical laboratoriesjust for wire and cathode coating, incharge of trained chemists.

The greatest obstacle encountered inthe production of good vacuum tubes isgas. Utmost precautions must be takento be sure that all the gas is removedfrom the tube before sealing. To this endthe pumping' is carried out as far aspossible within the economic time limit,followed by the flashing of a chemical or"getter" to clean up the remaining gases.The metal parts are frequently baked ina hydrogen atmosphere, so as to removeoxygen in the pores of the metal. Evenso, with nickel for the support wires, plateand grid, there is considerable imbeddedgas which is certain to be exuded whenthe tube is in use, resulting in gassy tubes.For this reason, molybdenum or "molly"plates are frequently used, also molybde-