Radio Broadcast (May 1929-Apr 1930)

-z. RADIO BROADCAST IN THE RADIO MARKETPLACE (Continued from page 277) up district offices in each territory and the district sales managers are now busily engaged in conducting jobber and dealer meetings throughout their respective districts, cementing closer contacts between the manufacturer and the dealers and getting the field in order for a record year. The five district managers are R. C. Hopkins, C. H. Griffith, J. G. Baquie, C. A. LindevaU, and J. A. Ramsey. R. C. Hopkins is at the head of the Eastern District, with an office at 39 Broadway, New York. His territory includes such distributing points as New York, Boston, New Haven, Albany, Rochester, Philadelphia, Baltimore, Syracuse, Scranton, Nashville, Atlanta, Miami, and New Orleans. The Eastern Central District with headquarters at 547 Leader Building, Sixth and Superior Streets, Cleveland, Ohio, has C. H. Griffith in charge. His distributing points include Cleveland, Cincinnati, Columbus, Toledo, Detroit, Muskegon, Pittsburgh, and Buffalo. Chicago is the headquarters of the Central District, with J. G. Baquie in charge. Jobber headquarters in this district include Chicago, Milwaukee, St. Louis, Peoria, Indianapolis, and Elkhart. Central District offices are now located at 702 London Guaranty Building, 360 North Michigan Boulevard, Chicago, Illinois. C. A. Lindevall is at the head of the Western Central District with offices at 550 Gates Building, Kansas City, Missouri. In his territory are Minneapolis, Mitchell, Omaha, Kansas City, Oklahoma City, Dallas, Houston, and Memphis. The Western District, with J. A. Ramsey in charge, includes San Francisco, Los Angeles, Portland, Seattle, Spokane, Boise, Butte, Salt Lake City, and Denver. Headquarters are located at 625 Market Street, San Francisco. HAZELTINE PATENTS UPHELD The decision of the Federal Court of Brooklyn in upholding the Hazeltine Corporation patents for eliminating undesirable generative effects in radio was affirmed July 2nd by the Circuit Court of Appeals. The Corporation, as a test case, sued E. A. Wildermuth, a wholesale dealer in Atwater-Kent models, which, it was alleged, infringed on the corporation's patents, applied for in 1920, and issued a year later. It was indicated that an appeal might be taken to the United States Supreme Court as all the Atwater-Kent models of that type are involved. The new Atwater-Kent screen-grid tube set is not involved, in the suit, however, although a Hazeltine representative is quoted as saying that a move against that type of set may be taken later. effective retail advertising B. B. Jolley, Atwater-Kent dealer in Morristown, N. J., is going far and wide to advertise and promote his sales. This progressive dealer's latest stunt is to take full back-cover space in local motionpicture theatre programs. "People who frequent movie theatres," says Mr. Jolley, "are red-hot prospects for the modern radio. That a definite part of their leisure time is devoted to entertainment— the more varied the better — is proved by their more or less regular movie attendance. I have found that this method of advertising is particularly effective, especially from a cost-versus coverage standpoint. The majority of the average local motion pictures programs are two or four page leaflets — easily and quickly read. Your radio message, covering one entire page at an extremely low cost, possesses immediate force and direct appeal." SPARKS-WITHINGTON INCREASES CAPITAL STOCK With business in hand to justify the promise of an unprecedented output of Sparton radios for 1929-30, and with the past season, a record year in profits the stockholders of the company authorized an increase in the capital stock from 400,000 shares to 2,000,000. At present there are outstanding 166,498 shares of common stock, and 7884 shares of prefferred stock. Captain William Sparks, president of the company, states that booked orders starting after July 1 amount to double the business prospect of a year ago. MAKERS TO EXHIBIT RAW MATERIALS Fdtty manufacturers of parts and raw materials have indicated their purpose to exhibit to the public at the forthcoming national radio expositions, the Radio World's Fair, in New York in September, and the Chicago Radio Show, in Chicago, in October. G. Clayton Irwin, Jr., general manager of the two shows, has completed details for a "Parts and Raw Materials Section" in the shows, and a "Parts and Raw Materials Directory" to be made available to all. Such a directory will fill a definite need. There is no single source to which radio manufacturers may turn for information regarding parts or raw materials which enter into set, speaker, tube, or apparatus construction. ADVANTAGES OF PRESELECTION (Continued from page 296) tor." This detector utilizes an ordinary heater-type tube such as is used in the amplifier. Suitable choice of operating voltages enable as high as 15 volts of modulated r.f. to be applied to the detector input without overloading. In practice, the volume control is usually adjusted to provide sufficient amplification for raising the voltage of the received signal to a value of about 10 volts. The amplified signal is impressed directly upon the detector which is in the same container as the radio-frequency amplifier. The output of this detector when a 10-volt signal is impressed upon the input is sufficient to operate directly the largest power tubes employed to-day. Power Supply Apparatus The single stage of audio-amplification employed in the Equase system has a gain of about 4S of the conventional two-stage audio amplifier. The demands upon the filter are reduced in like proportion. In fact, the resistance of the field coil in the dynamic loud speaker may be used in place of the choke coils usually employed, and but two filter condensers are needed; and the residual hum is inaudible! The saving in weight and size of power unit and the minimization of service troubles brought about by this simplicity, results in a great economy indeed. THE TUBE BUSINESS (Continued from page 278) OF interest to wire exporters Will manufacturers who desire to export tungsten-filament wire, oxidecoated wire, molybdanum wire, nickel ribbon, and wire net write to V. Hirota, managing proprietor, The Sun Denchi Seisakujo, No. 18 Zengenjicho, Nichome, Osaka, Japan. On June 10 this company desired names of manufacturers who sold such material for the construction of radio tubes. SYLVANIA HAS NEW LAB A "sales engineering laboratory" has been established at the Sylvania plant to aid in "rendering the utmost in service to the user of Sylvania tubes." This laboratory, housed in a neat brick building some distance from the main factory, and equipped with modern measurement instruments, life-test racks, etc., is under the charge of Walter R. Jones. The main purpose of the laboratory is to maintain a "control" on the quality of Sylvania tubes; to maintain close contact with the field, and lend assistance in technical problems in regard to sales. In maintaining control on Sylvania output, tubes made at Emporium as well as at other tube plants will undergo constant life tests. REGARDING TUBE LIFE Arcturus engineers believe that radio tubes receiving proper care in the average sets of to-day will last two years. If tubes need to be replaced at short intervals the A, B, and C voltages are probably wrong or fluctuate due to linevoltage variation. It would be interesting to have the experiences of a sufficient number of servicemen to answer the question, "in actual service how long do present-day a.c. tubes last?" KEEPING ABREAST OF THE TIMES "A radio plant is no stronger than its engineering personnel," says Ernest Kauer of CeCo. "No institution can keep moving forward unless it maintains the vigor and imagination of its engineering department. Frequently the engineer's tests demand a rejection of from 25 to 50 per cent, of the day's output. This is an awful blow for the head of a plant to have to accept — but there is no way out. High standards are more important than ever this year, for many institutions are seeking volume to such an extent that there is apt to be a careless attitude toward technical standards." new filament preparation A new process of coating the filament of a.c. tubes has been developed by Triad engineers. A non-oxide preparation is used which has proven highly effective in prolonging the life of the tubes. The Triad company, to quote Harry H. Stienle, sales manager, is a "new organization of old manufacturers." The company has floor space totalling something over five acres; has a daily capacity at present of 50,000 tubes which can be almost doubled when, and if, necessary or desirable; will spend more than a half-million dollars in advertising; will appoint only a limited number of jobbers. The Executive Officers are George Coby, president, Ely Egnatoff, treasurer, Harry Steinle, vice-president and general sales manager, and William Cepek, secretary. Its engineering staff includes S. U. Marie. Ph.D., Boger Williams, Ph.B., A. S. Friedman, Sc.B., and George Rylsky, E.E. M.E. • SEPTEMBER 1929 • 30 3