Radio Broadcast (May 1929-Apr 1930)

.RADIO BROADCAST ADVERTISER. 3T NABLE PRIDE Set Manufacturers in the QUALITY, SERVICE and DEPENDABILITY of POLVMET PRODUCTS FADA 'We use Polymet Products because a specialized part is needed to complete the high quality of Fada sets". "We use Polymet Products because they are definitely superior specialized parts". "We specify Polymet Partsin the Console 35 and other Stewart-Warnersets because we know that Quality radios can be made only with Quality parts". STEWART" WARNER KING "We want King sets to give complete satisfaction; with Polymet specialized parts we know that perfect service is assured". Is it any wonder then that Polymet supplies over 80% of the large set manufacturers with radio essentials? POLYMET MANUFACTURING CORPORATION 837 East 134th St., New York City CONDENSERS ■ RESISTANCES ■ COILS ■ TRANSFORMERS An Accurate Resistor 5 OHMS TO 5,000,000 OHMS THE Super Akra-Ohm Resistor, wire wound, has been designed with the primary thought of commercial acceptability. In order to insure an accuracy of i% and permanency of calibration, it is manufactured by a special process, (patent pending). BULLETIN NO. 62 which fully describes the use of the Super Akra-Ohm Resistor as a Voltage Multiplier, also contains the first complete chart for the employment of accurate resistors with microammeters and milliammeters. The Super Akra-Ohm Resistor is also especially recommended for use as Laboratory Standards, High Voltage Regulators, Telephone Equipment and Television Amplifiers, and Grid and Plate Resi tors, etc. Send Now for your copy of this useful Bulletin ti-Ec ELECTRICAL SPECIALTIES Ctollingdale, Pa.' A NEW Edition Thoroughly revised — greatly enlarged and offering a wealth of new up-to-the-minute information THE RADIO MANUAL Revised Edition Complete new chapters on aircraft radio equipment; Practical Television and Radiomovies with instructions for building a complete outfit; radio interference; 100% modulation; latest equipment of the Western Electric Co.; the Marconi AutoAlarm System ; and many other developments of the past year. All this information is added in the new edition and, besides, the entire book has been brought right up to date with much new material. The Radio Manual continues to be the one complete and up-to-the-minute handbook covering the entire radio field. A Complete Course in a Single Volume 20 big chapters cover: Elementary Electricity and Magnetism ; Motors and Generators ; Storage Batteries and Charging Circuits; the Vacuum Tube; Circuits Employed in Vacuum Tube Transmitters; Modulating Systems and 100% Modulation; Wave-Meters; Piezo-Electric Oscillators; Wave Traps; Marine Vacuum Tube Transmitters; Radio Broadcasting Equipment; Arc Transmitters; Spark Transmitters; Commercial Radio Receivers; Marconi AutoAlarm; Radio Beacons and Direction Finders; Aircraft Radio Equipment; Practical Television and Radiomovies; Eliminating Radio Interference; Radio Laws and Regulations; Handling and Abstracting Traffic. New Information Never Before Available including detailed descriptions of standard equipment is presented, such as a complete description of the Marconi AutoAlarm System ; the R. C. A. Direction Finders; the Western Electric 5-C Transmitter including all the newest equipment ; description and circuit diagram of Western Electric Superheterodyne Radio Receiving Outfit type 6004-C ; Navy Standard 2-Kilowatt Spark Transmitter; etc., etc. Every detail up to the minute. Prepared by Official Examining Officer The author, G. E. STERLING, is Radio Inspector and Examining Officer, Radio Division, U. S. Dept. of Commerce. The book has been edited in detail by ROBERT S. KRUSE, for five years Technical Editor of QST, the Magazine of the American Radio Relay League. Many other experts assisted them. FREE EXAMINATION The Revised Edition of "The Radio Manual" has just been published. Nearly 900 pages. 369 illustrations. Bound in Flexible Fabrikoid. The coupon brings the volume for free examination. If you do not agree that it is the best Radio book you have seen, return it and owe nothing, If you keep it, send the price of $6.00 within ten days. Clip and Mail This Approval Order Form D. VAN NOSTRAND CO., Inc., (Radio Broadcast 10-29) as* Fourth Ave., New York Send me the Revised Edition of THE RADIO MANUAL for examination. Within ten days after receipt I will either return the volume or send you $6.00 — the price in full. Name . St. and No. City and State. • OCTOBER 3929 • J • 369