Radio broadcast .. (1922-30)

254 RADIO BROADCAST ADVERTISER Would You Like To Earn More Money-inWork That '5 Almost Romance? 1 J. E. SMITH President If you're earning a penny less than $50 a week, clip coupon below. Get my big Free book telling about op- portunities for big money in Radio. Television, trans- Atlantic Radio telephony, many other wonderful inventions and developments constantly crea- ting big new Radio opportunities. Heres work that s almost romance, a NEW, speedy growing, live-wire profession. And Radio needs trained mm! Salaries from £50 all the way up to $250 a week are not unusual. You can easily learn Radio for bigger pay by my tested, practical methods. Hundreds of men have already done it You learn quickly in your spare hours AT HOME—it's all so interesting to you that it's easy! Extra Dollars For You Almost At Once Think of making £15, $ 2 o. £30 extra every week "on the side, without interfering with your regular job' I'll teach you to do it almost at once after you start your Radio training with me, by using spare time that you're wasting now. And all the while you'll be getting ready for the big- ger Radio jobs ahead I You can easily pay for your course and put money in the bank while learning, when you learn by my prac- tical methods. And you don't need to leave home, or inter- fere with the job you have now, while you're doing it! Fill out and maii the coupon below for the big book of Facts and Proof. Six' Big Out fits of Practice Ma te - rial Given Free of Extra Cost With your training you get free of extra cost 6 great outfits of real Radio practice material. With the=e 6 outfits you can build looreal Radio circuits. This is the practical kind of home-training. You learn to hold a job —not on paper — O N THE PAY-ROLL. Send coupon below lor ietails of this offer. 64-Page Book Sent Free When I receive your coupon I'll mail you my big 64-page Book immediately. It's filled with photos and facts about the opportunities in Radio, and tells how vou can prepare, quickly and easily in your spare time at home, to be an expert in this field. Noprevious Radio experience needed to take advantage of this offer. No special school- ingrequired. Mailcouponnow —address J. E. Smith, Pres. J. E. SMITH, President, National Radio Institute, Dept. H-94, Washington, D. C. Dear Mr. Smith: Kindly send me your 64-page Free Book which tells about learning Radio for bitter pay. Also send information on your offer of 6 outfits of material free of extra cost. I understand this places me under no obligation. Name., Address , ....«« Town State.. What Kit Shall I Buy? HE list of kits herewith is printed as an exten- sion of the scope of the Service Department of RADIO BROADCAST. // is our purpose to list here the technical data about kits on which information is available. In some cases, the kit can he pur- chased from your dealer complete; in others, the descriptive booklet is supplied for a small charge and the parts can be purchased as the buyer likes. The Service Department will not undertake to handle cash remittances for parts, but when the coupon on page 255 is filled out, all the informa- tion requested will be forwarded. 201. SC FOUR-TUBE RECEIVER — Single control. One stage of tuned radio frequency, regenerative detector, and two stages of transformer-coupled audio amplification. Regeneration control is accomplished by means of a variable resistor across the tickler coil. Standard parts; cost approxi- mately $58.85. 202. SC-II FIVE-TUBE RECEIVER— Two stages of tuned radio frequency, detector, and two stages of trans- former-coupled audio. Two tuning controls. Volume control consists of potentiometer grid bias on r.f. tubes. Standard parts cost approximately $60.35. 203. "HI-Q" KIT — A five-tube tuned radio-frequency set having two radio stages, a detector, and two transformer- coupled audio stages. A special method of coupling in the r.f. stages tends to make the amplification more nearly equal over the entire band. Price $63. 05 without cabinet. 204. R. G. S. KIT — A four-tube inverse reflex circuit, having the equivalent of two tuned radio-frequency stages, detector, and three audio stages. Two controls. Price §69.70 without cabinet. 205. PIERCE AIRO KIT — -A six-tube single-dial receiver; two stages of radio-frequency amplification, detector, and three stages of resistance-coupled audio. Vojume control accomplished by variation of filament brilliancy of r.f. tubes or by adjusting compensating condensers. Complete chassis assembled but not wired costs $42.50. 206. H & H-T. R. F. ASSEMBLY — A five-tube set; three tuning dials, two steps of radio frequency, detector, and 2 transformer-coupled audio stages. Complete except for base- board, panel, screws, wires, and accessories. Price $35.00. 207. PREMIER FIVE-TUBE ENSEMBLE — Two stages of tuned radio frequency, detector, and two steps of trans- former-coupled audio. Three dials. Parts assembled but not wired. Price complete, except for cabinet, $35.00. 208. "QUADRAFORMER VI" — A six-tube set with two tun- ing controls. Two stages of tuned radio frequency using specially designed shielded coils, a detector, one stage of transformer-coupled audio, and two stages of resistance- coupled audio. Gain control by means of tapped primaries on the r.f. transformers. Essential kit consists of three shielded double-range "Quadraformer" coils, a selectivity control, and an "Ampitrol," price $17.50. Complete parts $70.15. 209. GEN-RAL FIVE-TUBE SET — Two stages of tuned radio frequency, detector, and two transformer-coupled audio stages. Volume is controlled by a resistor in the plate circuit of the r.f. tubes. Uses a special r.f. coil ("Duo- Former") with figure eight winding. Parts mounted but not wired, price $37.50. 210. BREMER-TULLY POWER-SIX — A six-tube, dual- control set; three stages of neutralized tuned radio frequency, detector, and two transformer-coupled audio stages. Re- sistances in the grid circuit together with a phase shifting arrangement are used to prevent oscillation. Volume control accomplished by variation of B potential on r.f. tube. Essential kit consists of four r.f. transformers, two dual condensers, three small condensers, three choke coils, one 5oo,ooo-ohm lesistor, three i 500-0 hm resistors, and a set of color charts and diagrams. Price $41.50. 21 1. BRUNO DRUM CONTROL RECEIVERS — How to apply a drum tuning unit to such circuits as the three-tube regen- erative receiver, four-tube Browning-Drake, five-tube Diamond-of-the-Air, and the "Grand" 6. 212. INFRADYNE AMPLIFIER — A three-tube intermediate- frequency amplifier for the super-heterodyne and other special receivers, tuned to 3490 kc. (86 meters). Price $25.00. 213. RADIO BROADCAST "LAB" RECEIVER — A four-tube dual-control receiver with one stage of Rice neutralized tuned-radio frequency, regenerative detector (capacity controlled), and two stages of transformer-coupled audio. Approximate price, $78.15. 214. LC-27 — A five-tube set with two stages of tuned- radio frequency, a detector, and two stages of transformer- coupled audio. Special coils and special means of neutralizing are employed. Output device. Price $85. 20 without cabinet. 215. LOFTIN-WHITE — A five-tube set with two stages of radio frequency, especially designed to give equal amplifica- tion at all frequencies, a detector, and two stages of trans- former-coupled audio. Two controls. Output device. Price $85.10. 216. K.H.-27 — A six-tube receiver with two stages of neutralized tuned radio frequency, a detector, three stages of choke-coupled audio, and an output device. Two controls. Price $86.00 without cabinet. 217. AERO SHORT- WAVE KIT — Three plug-in coils de- signed to operate with a regenerative detector circuit and havinga frequency rangeof from 19, 990 to 2306 kc. (i5to 130 meters). Coils and plug only, price $12.50. 218. DIAMOND-OF-THE-AIR — A five-tube set having one stage of tuned-radio frequency, a regenerative detector, one stage of transformer-coupled audio, and two stages of resistance-coupled audio. Volume control through regenera- tion. Two tuning dials. 219. NORDEN-HAUCK SUPER 10 — Ten tubes; five stages of tuned radio frequency, detector, and four stages of choke- and transformer-coupled audio frequency. Two controls. Price $291.40. $10 $10 ASTOUNDING! **The only word that describes the repro- duction of the 'ENSCO' 3 foot Cone or Roll type Speaker." The statement of one of the foremost Acoustic Engineers. Kit GENUINE Kit "ENSCO" Why has "ENSCO" been endorsed by all leading magazines and the foremost newspapers? Because— it is the most highly developed big cone assembly now offered to the public, it reproduces all frequencies. The "ENSCO" unit is the only direct-drive unit for large cone speakers. Manufactured under U. S. Patent No. 1630119; "ENSCO" Cushion Drive Patent No. 1163854; Cone Diaphragm Patent No, 1003655, and other patents pending. Assemble the "ENSCO" speaker in less than an hour. It works on any set with any power. No fil- ters or chokes necessary, 90 to 250 volts without pro- tection or 500 volts with transformer. Six different types to choose from. Cones beauti- fully decorated and marked for assembly. Wall, pedestal, or console; all fully described in illustrated instruction book. Sold under absolute (money back) guarantee. ENGINEERS SERVICE COMPANY 25 Church St. New York City 73 Cornhill Boston 28 E. Jackson Blvd. Chicago Ask your dealer or mail order to nearest office. Send money order, check, or cash, or we will ship C.O.D. We pay shipping charges. Learn the Code at Home With the Omnigraph Morse and Wireless—taught at home in half usual time and at trifling cost. Omni- graph Automatic Transmitter will send, on Sounder or Buzzer, unlimited messages, any speed, just as expert operator would. Adopted hy U. S. Govt. and used by lead' ing Universities, Colleges, Technical and Telegraph Schools thro ughout U. S. Send 6c for Catalog. OMNIGRAPH MFG. CO., 13K, Hudson St., New York (RESISTORS L JL ARTHUR H. LYNCH, Inc. 1776 Broadway General Motors Building New York City RADIO FANS, a one-year's subscription to Radio Broadcast will cost you four dollars, two years six dollars. Consider this expenditure as beine a necessary investment on your part for the future develop- ment of your own knowledge of Radio. AMSCO ORTHOPHONE Connects instantly between radio set and loudspeaker. Permits volume without distortion. Protects the loudspeaker. Essential where power tubes are used. AMSCO PRODUCTS, INC. Broome and Lafayette Streets New York City