Radio Broadcast (May 1928-Apr 1929)

RADIO BROADCAST ADVERTISER 75 Look for the m on top of all i/itnningnafn JlC RADIO ^TUBES> HEN you look inside of your radio, be sure you see the monogram "C" smiling up at you on the top of each radio tube. Thirteen years of experience and tireless research combined with a guarantee against mechanical and electrical defect stand behind this simple monogram. Cunningham Tube quality has resulted in national leadership and public approval, two assets we zealously guard and is your assurance of faultless modern reception. k Never use old tubes with new ones — use new tubes throughout 1 E. T. CUNNINGHAM, INC. New York Chicago San Francisco Manufactured and sold under rights, patents and inventions owned and/or controlled by Radio Corporation of America. J IQUALITY PRODUCTS If It's Sponsored by Dongan It's O. K. As an exclusive specialist in parts then runs the gauntlet of Dongan's engineering and manufacturing, Don laboratory experiments; those merit gan, for years, has occupied a key ing further trial are subjected to every position in the industry. New test. Only when finally approved tubes, new hook-ups — new ideas by by the chief engineer is a new design the hundred — come to Dongan for offered to the market — a finished consideration. Every single idea product. One of the most successful Developments of 1928 Power Amplifiers built around UX 250 Tubes The following are Approved Dongan Parts for use with UX 250 tubes LIST No. 7568 — Transformer for full wave rectification using 2 UX 28I tubes to supply B and C power to receiver and power for 2 UX 250 tubes $13.50 No. 8529 — Transformer similar to No. 7568 with the addition of 2 low voltage windings, one for 226 tubes and the other for 227 tubes so that you can build a power amplifier for either radio receiver or phonograph pick-up 16.50 No. 6551 — Double Choke, for use with above transformers 15.00 D-600 — Power Amplifier Condenser Unit 16.50 D-307 — A Condenser Block, used in connection with D-600 . . . 10.00 No. 1 177 — Straight Power Amplifier Output Transformer 12.00 No. 1 176 — Same as No. 1177, but of Push Pull type 12.00 Custom Set Guilders can secure any of these items direct from factory at trade discounts. Set Manufacturers are offered the full cooperation of Dongan engineering department for their individual requirements. DONGAN ELECTRIC MANUFACTURING CO. 2991-3001 Franklin Street Detroit RADIO FANS, a one-year's subscription to Radio Broadcast will cost you four dollars, two years six dollars. Consider this expenditure as being a necessary investment on your part for the future development of your own knowledge of Radio. WRITE TODAY Send for large, new, illustrated Catalog "A-2," showing the latest of everything in radio at wholesale prices. ChaigingBatteriesj ]$tartsYou ; Let me show you how to make big moneyright from the start. I've prepared a FREE , book explaining all details. First week's profit pays for all equipment. You can get all the battery charging business in your community with my Service Station Charger — it's years ahead of ordinary chargers — handles 50% to 70% more batteries. I explain everything — start you in a business of your own and put you on the way t big money. Write for FREE BOOK. C. F. HOLMES. Chief Engineer, Dept R B Independent Electric Works S116 Ravenswood Ave. Chicago, ttj. Allied Radio CORPORATION til W LAKE STREET, CHICAGO ■