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JI F()IU 112~ A\ IL Vol Ctil:>S ()fficial JI f()IU 112~ A\ IL Vol. 4 No. I March 1979 Philo T. Farnsworth • Those Wild Hams of the '20's Protectina Broadcastinas Past • Collector SPotliaht: Jim Enaland Maiestic Radio Restoration • The Flemina Valve C:til!S ()fficial JI f()IU 112~A\ IL Uol. 4 No. 1 March 1979 THE SOCIETY: The California CONTENTS Historical Radio Society is a non- profit corporation char­ tered, in 1974, to pror.iote the Those Wild Hams restoration and preservation of early radio and radio broad­ of the '20's. 1 casting. CHRS provides a me­ dium for members to exchange Beautifying That Old Radio. 5 information on the history of January Swap Meet . 6 radio, particularly in the west, with emphasis in areas Protecting Broadcasting's Past. 9 such as collecting, cataloging and restoration of equipment, FEATURE: Horn Speakers. .11 literature and programs. Reg­ ular swap meets are scheduled Philo T. Farnsworth .20 at least four times a year, in Novelty Nook. .23 the San Jose area. PRES I DENT: No rman Berge Spotlight Collector: SECRETARY: Dave Brodie Jim England . 24 LEGAL COUNSEL: Eugene Rippen TREASURER: James Cirner Majestic 20/23 Restoration. 25 JOURNAL ED ITOR : Allan Bryant PUBL ISHER AND PRINTER : Don Tube Column . 28 Stoll PHOTOGRAPHER: George Durfey Collectors' Ads inside back TUBE EDITOR: Russ Winenow TECHNIC/1.L EDITOR : Floyd Paul CIRCULATION MANAGER: Larry LaDuc, Jr. MUSEUM DIRECTOR AND COORDINA­ Graphic material "borrowed" TOR: To Be Announced, 1979 liberally from Radio News (pub­ DR. CHARLES 0. HARROLD AWARD lished by Experimenter-Publish­ RECIPIENT: Bruce Kelley, ing Company, Hugo Gernsbach , (AWA) (19 78 ) President) and Radio Retailing HONORARY LIFETIME MEMBER: (McGraw-Hill, Inc.). Paul Courtland Smith (1978) THE OFFICIAL JOURNAL of CHRS is published quarterly a nd furnished free to all members. The first issue (published in CHRS Official Journal is pub­ Sept. 1975) is still avail­ lished by California Histori­ able ($2.00) , other early is­ cal Radio Society , Box 114 7, sues are $1 . 00 each. Articles Moun tain View, CA 94040. Ar­ for the Journal are solicited ticles and non-commercial ads from all members. Appropriate for the Journal should be sub­ subjects include restoration mitted to Allan Bryant, Editor, hints, information on early 38262 Ballard Drive, Fremont, radio broadcasts and personali­ CA 94536. Historical data ties, anecdotes about the pio­ for copying or dona ti on should neers, etc. Anyone interested also be sen t to the Editor. in assisting in producing the Journal should con tact the Contents © 1979, CHRS, Inc. 0 Editor. Those Wild Hams of the ·2o·s by Charles C. Hay, W¢LCE (now called capacitor) went for $15. So, most of us were It was a glorious time to forced to build our own equip­ live -- back in the 1920's, ment. when radio communication was The usual receiver consis­ just beginning to emerge. Only ted of a coil of wire wound a­ a very few top scientists knew round an empty oatmeal box; anything about this new medium another coil inside the box -- and most of the things they was rotated by a lead pencil "knew" were incorrect. But pushed through the box and that didn't deter them from b~th coils. This pair of displaying their errors -- coils was connected to a fine what thev thouqht were "facts" wire sharpened to a point. -- in the public press. The point made contact with One of the notable "facts" the surface of a galena crys­ that qot around was the state~ tal. The body of the crys­ ment that radio communication tal was connected to one lead was impossible below a wave­ of a pair of headphones, and length of 200 meters. (for the other lead of the phones those of you familiar with was connected to ground. With only hertz, 200 meters is a long-enough length of wire 1500 kHz.) So, Congress for the antenna, this contri­ dreamed up a radio law that vance could receive radio sig­ confined all amateur communi­ nals from as far away as 1000 cation to the bands below 200 miles. It needed no outside meters -- or above 1500 kHz. power since all the power was The law also specified that furnished by the radio waves all radio stations had to be themselves. licensed. Little problem While vacuum tubes were that, since a license was known in the early 1920's (they granted upon request and with­ were used in World War I) , they out the applicant having to weren't available, except to a submit to an examination. very few lucky individuals. Another part of the law Everyone used a tubeless spark stipulated that only in the transmitter, anyway. big cities were licenses to A spark transmitter was easy be granted. Needless to say , to build. It required simple since many experimenters materials, like a spark coil lived a long way from the big from a Model T Ford, a pair of cities, a lot of transmitters sharpened zinc strips (to act were on the air without the as the spark gap), a telegraph benefit of licenses. What­ key, and an antenna. By con­ ever call letters were used necting the spark coil through were self-assigned. the telegraph key to an auto­ We Built Our Own Equipment: mobile battery, and the secon­ All-Of the eq\iTpment we early dary of the coil through the hams used was homemade. There spark gap to the antenna, a guy were only two companies in the entire United States that sold radio parts, and their prices Reprinted from Popular were quite steep. For example Electronics Magazine, Copy­ $20 would buy a link coupler. right ® 1973. Ziff-Davis while a variable condenser Publishing Co. was in business. When he pres­ sed the key, he drew a lovely spark from the gap . The spark could be received clear across town, if the town wasn't too big, that is. Although the receiving sta­ tion had a tuner, it wasn't necessary. Those spark trans­ mitters were the original all­ band transmitters. When they came on the air, any nearby re­ ceiver, no matter where tuned, would pick them up . Along Came Tubes : Late in the 1920's;-Yacuum tubes be­ came available. About the same time, commercial broad­ YOU ARE INVITED casting reared its head. Peo­ to join CHRS and enjoy : ple with money could buy broad­ 4 quarterly issues of this cast receivers, precipitating Journal the unpopularity of the neigh­ 4 quarterly swap meets borhood experimenter, with his Free ads in every issue of all-wave spark transmitter . the Journal Technical advice on your res­ Government regulations, toration problems, etc. which instituted "silent hours" for Sunday mornings and until Annual membership -- $9.00 10 o'clock each evening, came Seniors (over 62) -- $6.00 into effect. Not that this For applications contact: did much to the experimenter. Dave Brodie He usually didn't read gov ern­ 315 Cotton Street ment publications, so he knew Menlo Park, CA 94025 nothing of the regulations . or call the nearest represen­ tative: At the time the new regula­ tions came into effect, radio SACRAMENTO communication was administered Jim England by the Department of Commerce, 6875 Escallonia Drive which had other things to do Orangevale, CA 95602 (9 16 ) 725-6625 besides supply money for radio enforcement. With the absence MOD ESTO of enforcement , the young ra­ Eddie Enriques dio experimenter wasn't much 1824 Wy lie Drive troubled . But there were neigh­ Modesto, CA 95355 borhood relations to consider, (209) 529- 7596 and if interference was over­ RODEO done, the neighbor with his Ronald DeLucchi high-priced broadcast set was 1028 Seascape Circle likely to take the matter up Rodeo, CA 94572 with the offender's parents . (4 15) 799- 2270 This usually resulted in the GLENDALE enforcement of "quiet hours" Floyd A. Paul -- if it didn't terminate ex­ 1545 Raymond perimentation altogether. Glendale, CA 91201 (213 ) 242- 8961 I was one of the experimen­ SAN DIEGO ters in the early days of ama­ C. Alan Smith teur radio. The fact that I 6368 Charing Street could hear broadcasts on my San Diego, CA 92117 cry stal-detector tuner intri­ (7 14 ) 268-3620 gued my parents to the point where they shelled-out enough money for a v acuum tube, a Crosley book-condenser and a v ariable tuner. With these treasures on hand, I was able 2 to build a new-fangled super­ than the inner diameter of the regenerative receiver. copper cylinder, soldered to A by -product of my new re­ it a length of wire, and slip­ ceiver was the fact that the ped the new assembly into the copper cylinder. When I was superregen was itse~f a trans­ mitter. It interfered mightily finished with this step, the with our neighbor's neutrodyne wires from both assemblies pro­ receiver. But that was a prob­ truded from opposite ends of lem between my parents and the the glass tube. neighbor. Recovering a length of fila­ The superregen would pick ment wire from a light bulb, I up commercial broad~asts. It slipped this down the center was also adept at picking up of the coiled wire. After us­ amateur transmissions (after ing rubber stoppers to seal my parents had gone to bed, of both ends of the glass tube course). By this time, ama­ (with the wires protruding, of teur operators had acquired course), I applied sealing wax vacuum tubes. Some of them to assure an airtight seal. were even communicating via Later, at school, I attached voice ('phone) ! a rubber hose to the 1/ 4" glass tube and used a vacuum pump to My desire for a tube trans­ evacuate the air until the rub­ mitter could be described as a "consuming passion." But ber tubing went flat.
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