Radio Broadcast (May 1928-Apr 1929)

RADIO BROADCAST ADVERTISER 235 A manufacturer can have no greater faith in his products than to guararv tee faithful operation and with such a guarantee all TOBE PRODUCTS are sold. Write for pamphlet on TOBE PRODUCTS TOBE DEUTSCHMANN CO. S CAMBRIDGE, MASS. A EROVOX Filter Condenser Blocks and Resistors are Built Better. They will ENDURE! The Aerovox Research Worker is a free monthly publication that will keep you abreast of the latest developments in Radio. A postcard will put your name on the mailing list. EROVM. "Built Better" 78 Washington St., Brooklyn, N. Y. RADIO PANELS BAKELITE— HARD RUBBER Cut, drilled and engraved to order. Send rough sketch for estimate. Our complete Cataloe on Pnnels, Tubes and Rods— all of genuine Bakelite or Hard Rubber — mailed on request. STARRETT MFG. CO. 521 S. Green Street Chicago, 111. ROBERT S. KRUSE Consultant and Technical Writer 103 Meadowbrook Road, West Hartford, Conn. Telephone Hartford 45327 An Attractive Subscription Offer FOR READERS OF RADIO BROADCAST Don't miss this Special Offer to subscribe to Radio Broadcast — for the next 8 months. If you buy or build, make or sell, anything in radio you need to read RADIO BROADCAST Eight months for $2.00 RADIO BROADCAST Garden City, N. Y. Enclosed is Two Dollars for the next eight issues to commence with Name Address City . State Type 585 Amplifier Transformers THE General Radio Company announces a new group of high quality transformers at a direct to the consumer price. This new group consists of two instruments, the type 585-D and the type 585-H, the amplification characteristics of which are shown below. Type 585-D Ratio 1 :2 Pri. Inductance 79 H. Type 585-H Ratio 1:3.5 Pri. Inductance 71 H. Price, either type $7.00 New Prices. Write for new catalog No. 930 listing new low prices on all General Radio parts on a direct from the factory basis. GENERAL RADIO COMPANY BO State Street, Cambridge, Mass. 274 Brannan Street, San Francisco, Calif. Commercial Radio Institute (FOUNDED 1920) Resident School Only. All Branches Taught. Laboratory. Workshop. School Thoroughly Equipped. Graduate Certificates Day and Evening Classes. FALL CLASSES SEPTEMBER 24th. Literature. 10 East Centre Street, Baltimore, Md. FOR SALE Western Electric Tyre one naught six a one thousand Watt Transmitter complete, with remote control, studio and speech inputs. Antenna system with eighty foot towers. Spare parts, etc. Less than year old. Inventory upon request. Box 2, Radio Broadcast, Garden City, L. I. Fahnestock Clips RADIO'S GREATEST CONVENIENCE Used by Manufacturers of Standard Sets and Parts — and by Manufacturers of High Grade Wet and Dry Batteries. ALL GENUINE FAHNESTOCK CLIPS bear our imprint on the thumb piece of the clip. WORLD'S LARGEST MAKER OF CLIP TERMINALS 48 different sizes and styles to meet all requirements. Send for Catalog and Samples FAHNESTOCK ELECTRIC CO. L. I. City New York I r"\ r A CI A handy manual of I I—/ L.MO . 36 pages and cover —88 illustrations— over 20.000 wordspractical — concise — understandable — prepared by Austin C, Lescarboura and our engineering staff. That's "The Gateway to Better Radio" — yours for 25c, from your dealer or direct from us. American Mechanical Labs., Inc. Specialists in Variable Resistors 385-7 N. Sixth St.. Brooklyn, N. Y. the Code Al hi'M Only the code gi' th the Teleplex ( ode Instrnc No experience necessary. Provides practice when, where and how you ,ntit Reproduces actual sending of expert operators Sends messages, radiograms, etc. — regular code traffic. No better method of self-instruction exists. Endorsed by U. S. Navy and leading schools. Complete course of instruction!! (Wireless or Morse) furnished. Learn what's going on below the broadcasting line, you the thrill of real DX. Write now for book let BR 5, TELEPLEX CO., T*> C'ortlandt St., New York. RADIO FANS, a one-year's subscription to Radio Broadcast will c<"»st you four dollars, two years six dollars. Consider this expenditure as being a necessary investment on your part for the future development of your own knowledge of Radio. Asklor if bvNAME v j / a-m-p-e-r-i-t-eA ,/ the only eelf-adjustingY / control that maintains V / constant filament volt \& ' age, despite variations in "A" supply. Essential with elii inators. Ask for AMPKKITE by name and accept nothing else. Entirely unlike fixed resistors. A type for every tube— battery or A.C. RADIALL CO. 50 Franklin St.,INewYork FREE "Atnperite Blue Booh" of popular circuits and latest construction data Write Dept. R.B.-8 RIT1 7he "SELF-ADJUSTING" Rheostat