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From Coherer to Spacistor-'L'

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From Coherer to Spacistor-'L' APRIL, 1958 ! Formerly RADIO-CRAFT Incorporating SHORT WAVE CRAFT TELEVISION NEWS RADIO & TELEVISION SPECIAL FEATURE 45 From Coherer to Spacistor-'l'. R. Kennedy Jr. ON THE COVER-, I EDITORIAL (story on page 68) Some final soldered con- 31 Fifty Years Hence-Hugo Gernsback nections on the plug-in assembly of the Digitoir- AUDIO-HIGH FIDELITY an airborne digital com- V 32 Five New Audio Circuits-Robert F. Scott puter-are made by Cath- 36 WWV Offers Additional Services erine Bochat at the Hughes V 37 Playback Preamp for Stereo Tape-A. C. Moller Jr. Aircraft El Segundo, Calif. 38 News for the Audiophile-Herman Burstein plant. 40 High-Fidelity Amplifier Design and Performance-Mannie Horowitz Color original by 43 New Records-Reviewed by Chester Santon Hughes Aircraft Co. L I TEST INSTRUMENTS V 60 Synchronized Electronic Switch-Tom Jaski 64 Fix Your Scope-Rhys Samuel 67 Utility Voltmeter-Albert Stratmoen 69 Signal Takeoff For YOL~Audio VTVM-Frank Woods, Jr. Hugo Gernsbark"R RADIO ..............Ed11 tor and Publlshl M , Harvey Gernslback V 70 Servicing Oscillation and Regeneration in Transistor Radios ....................Edltorlal Direct% -Tames A. McRoberts Fred Shunaman ... Manaalnl- -- Edit 88 The Transistom-Mohammed Ulysses Fips Robert F. Scott 90 Uncommon Difficulties-A. R. Cla\vson ......WZPWG, Technical Edit rry Steckler ......................Assistant Edit1 WHAT'S NEW uueen ..................E dltorial Associate 93 Pictorial Report of New Developments ~bertG. Middleton ............ Telelrlslon Consultant EI izabeth Staltt~ TELEVISION !ductlonManager 94 Taming the Horizontal Oscillator-Wayne E. Lemons C? Llslng ProductlcIn 96 TV Service Clinic-Conducted by Robert G. Middleton W in. Lyon McLat tghlin 102 New TV Tube Does Three Jobs-Fmnk Hadrick ....Tech. Ill1ustratlon Dlrecior 104 Apostrophe to an Intermittent-Jack Darr 51>I Ehrllch 106 Closed Circuit TV at Penn State ................... .........Art Director Fr ed Neinast V 115 Color Selection with the Chromatron Tube-Lloyd W. Allen .............................. Staff Artist Le !e Robinson ELECTRONICS ....................General Manager Ja thn J. Lamson .....Sales Manager 68 Digital Computer Guicles Jets (Cover Feature) ................... G. Aliquo . V 120 The Industrial Servo Amplifier-Forrest H. Fmntz, Sr. ..............Clr culatlon ManaaIer 122 Tone Modulator for R-C-E. L. Safford, Jr. Aaam.. J. pmlrn.. ... .... Director, Newsstand Sales 126 Transformer Shielding-A. V. J. Martin Robert Fallath ................PI romotlon Manager 154 Books 137 Patents 148 Business and People 1:39 Radio-Electronic Circuits 18 Correspondence 151 Technical Literature 145 New Devices 134 Technicians' News 132 New Tubes ancl Semiconcluctors 128 Tcchnotes 6 News Bricfs 142 Try This One Average Paid Circulation Over 195,000 11-111...... - Associate Member RADIO-ELECTRONICS is Indexed in Applied Science C Technology Index (Formerly Industrial Arts Index) 5 Institute of High Fidelity Mfrs., Inc. RADIO-ELECTRONICS. .\vril 195s Yol. SXlX. Sn. 4. IB~~blisl~e~l111ont11iy at 311. ninrris. 111.. 11)- (:(;r~lslmc~<1,11I,li(.itli011<, IIIC. S<,COIIII-CIII-~S nli~ilnrivilrb'es nr~fl~orized .\It. Ilol.ris 111. (.nv).rixl~t is'8 1;; c:ernsl)xrli I'l~l)lin~tions.Lnc. .\I1 richrs r~'s~rv<'cI-111~1vt. IJnirrrsal 1ntel.nntiunnl anrl I';ln-.\t~~r,ri<xn('orl~rigltt ('onre.ntion*. SUBSCRIPTION RATES: Ti. S: U. S. vosessions and Canada. $4.00 for one year: $l.(l0 for trvo yrn1.s. $n.no for three years: slncle copies ::5c. I'a11-.4nlc~rican countries 84.50 for one Yr3nr: $8.00 for two years: $10.50 for three ypara. .\I1 other countries $5.00 a pt-ar: $9.00 for twb years. $12.00 for three years. SUBSCRIPTIONS: ,\,i(lr~sg ct~rrc~svonclmceto Radio-l~lcctro~~ics,Snbscrivtion Dept.. 404 N. Wesley Ave., llt. ikorrie, Ill..or 154 Wrst 14th St.. Krw Tork 11. N. y. men r~llllrstill!2a cl1'1nae of n(1rirPss Dleasr f~~rllisllan addrrss 1~1hr1frnm x rwmt is.;^^?. .\llow ollp lllontll for cllanar of address. GERNSBACK PUBLICATIONS. INC. Executive. Editorial ind ~dvertisingORices. 164 \\.[,st 14ti1 st.. s,.,v York 11. N. T. 'r,.~,~vl~ot~c~.\I~un~tr~in 3-iiS3. Hut10 Gernshack. ( I~:III~I~I;IIIof tllr 13narrl: M. Harvey Gernshack. President: G. Allquo. Secretary. BRANCH ADVERTISING OFFICES :anrl FOREIGN AGENTS list,,rl on u:~~~t.169. POSTMASTER: 11 ~ttlrl~~!iri~r;tlrlc~..vnd IJortll ::>;!I to: ~:.\~~O-ICT.I?~TI~O~"I('S,164 West 14th St.. New York 11. N. Y. Trademark rpglsterrd U. S. Pat. Offlee. 4 RADIO-ELECTRONICS 50 years ago this month the world's first radio maga- zine was launched. It---and those that came after it- played an important part in the half century of elec- tronic progress that followed. The first issue--Modern Electrics for April 1908. By T. R. KENNEDY, Jr. HALF-CENTURY ago-April, 1908-Mod- So much explanatory material was needed in those days ern Electrics, the world's first publication to tell about what the Electro Importing Co. had to sell to designed to explain and popularize "wire- electrical experimenters and wireless enthusiasts that the less," was published. Its editor and founder, company's voluminous catalog often contained long explan- Hugo Gernsback, was a Luxembourgian who atory articles. Gernsback found himself already a publisher had come here in 1904 as a south of 19, to of electrical and wireless information, and it was but a market his first invention, a layer-built dry-cell battery: step to a regular monthly periodical. With his new battery-which he had patented in Europe Though he used the conservative Modern Electrics as a -the young inventor brought many new ideas and devices title (a "radio" magazine pure and simple could hardly with him. It was not long, therefore, before a new company have survived in 1908) the very first article of that original to import, manufacture and market devices for the electrical April issue was entitled "Wireless Telegraphy." Another and the new group of "wireless" experimenters, made its article "by our Brussels correspondent" described a wireless- appearance. Called the Electyo Importing Go., it occupied equipped automobile. There was also a piece about long- a small loft at 32 Park Place, later a larger one at 87 War- distance records established by the United States fleet, ren St. and still later at 84-86 West Broadway, in lower whose transmissions from the west coast of Mexico had Manhattan; a little later, there was added a retail store at been received at San Francisco and at Pensacola, Fla. 68 West Broadway, the world's first radio store. The first issue contained 40 pages. Price was announced Among other items, the E.I.Co. began marketing the as 10 cents a copy-$1 per year. first home or private radio ever offered the public. Called In the very next issue of Modern Electrics (May, 1908), . the Telimco (from The E.I.Co. name) wireless telegraph Gernsback elaborated on his Telimco dot-and-dash wireless outfit, it was advertised in Scientific American in January, with an invention he called the Dynamophone, in ,which the 1906. Sales were slow at first-the new company had to human voice, through a microphone, coupled to a spark convince not only the public but the police that the device coil, transmitted to a distant receiver enough energy to would send signals through the air without wires-but it operate a relay and start an electric motor. This might be soon became the most important product of the E.I.Co. called the great-granddaddy of today's numerous voice- The original Telimco model is now in the Ford Museum at operated systems now used in oceanic radio and elsewhere. Dearborn, Mich. In subsequent issues he commented on the electric tubes Early picture of the Electro Importing Co.'s first retail store -the world's first radio store-and the type of equipment that was sold before 1910. APRIL, 1958 45 An early E.I.Co. scene. Not only was manufac- turing and shipping carried on here, but Modern Electrics was edited on the premises too. I<eplica of "the fit-st raclio set ever solcl to the l~ul~lic,"a slnall spark transmitter ant1 t.eceiver, now rests in Ford M~IS<.UIIIat Dearborn. This set was demonstratetl at the IRE convention in 1954, the last time spark transmission was a~t:.horizedby the FCC. then in existence, based on the Geissler and Crookes bulbs. July's Modern Electrics carried an article by V. H. Laughter on "Speaking Arc Lamp," forerunner of the high-power arc transmitters, the arc flame of which was "modulated" printing of the proposed Burke Wireless Bill, which was by stepped-up voice frequencies. About a year later, Valde- devised to "regulate and control the use of wireless tele- mar Poulsen developed and announced an arc transmitter graphy and wireless telephony." This Was one of the first that covered 150 miles on first test. Laughter, incidentally, actions in the struggle against Federal attempts to "reg- has continued as an author in these magazines to present ulate" the amateur into oblivion or ineffectiveness, in which times. One of his latest articles (June, 1950) was on the Gernsback publications were to take so active a part. "Making Large Electrets." In Modern Electrics of May, 1910, it was learned that A "loud-speaking telephone," which could be heard with- Bellini and Tosi, two Italian experimenters at Boulogne, out pressing the device against the ear, was offered by the whose work had been reported on in the March and May, Modern Electrics Berlin correspondent in the September, 1909, issues, had devised a system of directing wireless 1908, issue. Actual contact with the ear, and thus the waves in space. The process could be reversed-incoming possibility of picking up germs from the device, was said waves could reveal the direction from which they arrived.
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