Radio Broadcast (May 1928-Apr 1929)

THE MARCH Oh KMSD Nb.W.S AND INIimWIAnON QEXEEEEKI KADIO KVKNTSTT The Laboratories Grapple with Aircraft Radio AIRCRAFT radio, during the last few Z_\ weeks, has performed with such spec■*■ tacular effectiveness that any aviator who now attempts a long distance flight without its aid is flaunting providence. Since the July March of Radio editorial, scoring aviation for neglecting radio, was written, the world has been able to trace, through frequent radio bulletins, the progress of several amazing long distance flights. Three aviators flew from San Francisco to Brisbane in three tremendous jumps, with the whole world rooting for their success as they fought through wind and storm. The first transatlantic flight with a woman passenger was similarly applauded. Nobile and his companions were found in the Arctic drift only through the effectiveness of radio directions. Radio has covered itself with glory as the faithful companion of the aeronaut, guiding him through storm to distant airport, reporting his progress to the world and, finally, performing incredible missions of rescue. Spectacular feats are the vehicle by which the world is informed of the progress of science. The real advances are made in scientific laboratories where a few geniuses, aided by a staff of assistants, grapple with the problems which carefully tabulated study of known performance reveals as the need of the times. The world is startled into consciousness by its Lindberghs and Nobiles because technicians are not salesmen. Recent technical literature records victories of the laboratory as significant and important as the performances which make headline material for the press. Two papers were presented before the New York section of the Institute of Radio Engineers on June 6, which set forth the present development of aircraft radio equipment in a comprehensive and authoritative manner. One of these, " Development of Radio Aids to Navigation," by Dr. J. H. Dellingerand Haraden Pratt, traces the history of aircraft beacons from their war service to the present. The interlocking type of directive beacon, which automatically gives visual indication to the pilot as he flies along any well equipped airway, is the culmination of years of practical development work by the Bureau of Standards. No bearings need be taken either by goniometric stations on the ground or by the aviator in flight, a dial in the plane's instrument board serving to show whether the plane is on its course or to the right or left of its course. Dr. Dellinger's beacon system will save more lives in the next ten years than the parachute. Assisting Dr. Dellingerwas F. W. Dunmore, who contributed basic ideas to the modulation type of beacon and did much of the laboratory work. Harry Diamond is credited with valuable contributions in the design and construction of airplane receiving sets and research incident to the practical operation of the beacon and its modulating arrangements. Dr. E. Z. Stowell is mentioned by Dr. Dellinger for his work with earlier circuit arrangements and studies of field intensity diagrams. The second paper, delivered at the same meeting of the Institute, is entitled "Aircraft Radio Installations," by Malcolm P. Hanson of the Naval Research Laboratory at Anacostia. It describes the various transmitters installed aboard the dirigible Shenandoah, including the 2-kw. i. c. w. transmitter which gave good night reception on one occasion for a distance of 5000 miles. Mr. Hanson also describes the 1 50-watt transmitter aboard Byrd's plane, the America, those aboard the Old Glory, the American Legion, Wilkins' short-wave set and several transmitters developed by the Navy and the Burgess Laboratories. This comprehensive review indicates that aircraft radio equipment is in a high state of development and it is to be hoped that the radio industry follows up the advantage which it has gained by the recent practical demonstrations of radio's service to long distance flights. A nationwide net of radio communication to support commercial aviation is radio's newest mission which should be pursued with the utmost vigor. Only with such cooperation will radio demonstrate its true value as an adjunct to air navigation. A MODERN AIRCRAFT INSTALLATION Guggenheim Fund Shows the Way to 'Frisco THE Daniel Guggenheim Fund for the Promotion of Aeronautics has announced that it will install, along the Los Angeles-San Francisco airway, a complete aeronautic weather reporting service. Cooperating with the fund are the Aero Service of the Weather Bureau and the Pacific Telephone & Telegraph Company Two terminal stations are to be erected at the ends of the route, supported by twenty-two observation stations. The total time for the collection of reports at both terminals and the exchange of complete data between them will be less than twenty minutes. The reports are to be made three times daily a~d are to be communicated by telephone and radio to trained meteorologists who will forecast flight conditions and advise departing pilots which of five alternate routes should be followed. At the N EM A Convention DURING its session in Chicago, the Radio Division of the National Electrical Manufacturers' Association adopted a number of resolutions which were based on sound commonsense, making a pleasing contrast to the stand taken by some of the radio industry's representatives last April, before the Federal Radio Commission, in practically opposing the Engineers' Plan of Allocations. The Association recommended that "greater consideration be given to those stations which broadcast programs satisfying a wide variety of interests or groups," and it condemned those which " now act purely as house organs in selling merchandise for one firm or which exclusively broadcast programs devoted to furthering the interests of some particular group, creed or class." This is a direct fling at stations acting as advertising mediums for one advertiser and those owned by a single political party, church or sectarian group. The Association directly approved the Engineer's Plan of radio broadcasting channel allocation. DURING the convention, NEMA announced the publication of The Radio Market, which is a valuable analysis of how radio is distributed, the stocks of all classes of radio goods in the hands of dealers, classified both by geographical distribution and by cities of different sizes. A study of the analysis shows that there are too many radio outlets in cities of a million and larger and that the dealers in cities of from 500,000 to a million appear to be in the most favorable position with regard to size of stocks and turnover. The dealers in the smaller communities usually combine associated lines in a manner which counterbalances their smaller radio turnover. The number This radio telephone and telegraph transmitter and receiver is installed on a British commercial air liner. The transmitter is rated at 150 watts. The instrument box below the table contains at the top the receiving unit. Below it are the transmitting tubes, and at the bottom the tuning controls for the transmitter. The reel at the left unwinds the trailing antenna 253