Radio broadcast .. (1922-30)

Radio Broadcast When it comes to the supports for the aerial, the ideal mast is one made of insulating material. Wooden structures are an approximation of the ideal, although they are unsatisfactory for use in the tropics. Steel structures, on the other hand, are parasitic — they take away from the useful radiation of the station, although much of the parasitic loss can be overcome by insulating various portions of the mast and placing the mast on an insulating base. The conditions for receiving have also received considerable study, and experiments have been conducted with a view to developing suitable directive systems which would reduce interference to a minimum. It is suggested that each station should have as many receiving units as the number of stations with which it is to communicate. The receiving units should be grouped together at a distance of 20 to 40 miles from the transmitting station. Static — that bugbear of long-distance radio communication — comes in for its share of attention. Experience recently gained in England and Egypt is reported to indicate that atmospheric interference may be appreciably reduced by each of three distinct methods as follows: (i) Atmospheric balancing, in which an ingenious system of tuning causes the more or less complete cancellation of the undesired static. (2) Limiting the strength of the received signals, and therefore the strength of the atmospheric disturbances at the same time, since increasing the sensitiveness of the detector and the degree of amplification generally increases the static noises to such a degree that even the amplified signals are not clearly heard. It is better to receive weaker signals through very slight static. (3) Barraging, which is an elaborate tuning system for reducing static. All of which gives John Bull's radio men plenty to do, for the present. SUPPLEMENTAL LIST OF BROADCASTING STATIONS IN THE UNITED STATES FROM JUNE 16 TO AUGUST 10 INCLUSIVE CALL SIGNAL OWNER OF STATION LOCATION OF STATION WAVE LENGTH AGI Signal Corps School San Francisco, Calif. KDPM Westinghouse Elect. & Mfg. Co . Cleveland, Ohio. . KDZT Seattle Radio Assn Seattle, Wash. . . KFAC Glendale Daily Press Glendale, Calif.. . KFAD McArthur Bros. Mercantile Co Phoenix, Ariz. . KFAE State College of Washington Pullman, Washington KFAJ University of Colorado Boulder, Colorado KFAN Electric Shop Moscow, Idaho . KFAP Standard Publishing Co Butte, Montana. . KFAQ City of San Jose San Jose, Calif. . . KFAR Olesen, O. K Hollywood, Calif. . KFAS Reno Motor Supply Co Reno, Nevada . . KFAT Donohue, Dr. S. T Eugene, Oregon . KFAU Independent School District of Boise City Boise, Idaho. KFAV Cooke & Chapman ... Venice, Calif. KFAW Radio Den, The Santa Ana, Calif. KFBA Ramey & Bryant Radio Co Lewiston, Idaho KFBB Buttrey & Co., F. A Havre, Mont. . KFBC Azbill, W. K San Diego, Calif. . KFBD Welsh, Clarence V Hanford, Calif. . . KFBE Horn, Reuben H San Luis Obispo, Calif. KFBF Smith, F. H. . . . • Butte, Mont. . KFBG First Presbyterian Church Tacoma, Wash.. WAAB Jensen, Valdemar New Orleans, La. WFAU Lewis, Edwin C. Inc Boston, Mass. . WFAV University of Nebraska Lincoln, Nebr. . . WFAW Miami Daily Metropolis Miami, Fla. ... WFAX Kent, Arthur L Binghamton, N. Y.. WFAY Daniels Radio Supply Co Independence, Kansas WFAZ South Carolina Radio Shop Charleston, S. C. . WGAC Orpheum Radio Stores Co. Brooklyn, N. Y. . WGAD Spanish American School of Radio Telegraphy Ensenada, Porto Rico WGAF Goller Radio Service Tulsa, Okla.. . . WGAH New Haven Elect. Co New Haven, Conn.. WGAJ Gass, W. H Shenandoah, Iowa . WGAL Lancaster Electric Supply & Const. Co Lancaster, Pa. . . WGAM Orangeburg Radio Equipment Co Orangeburg, S. C. . . WGAN Lloyd, Cecil E Pensacola, Fla. . . . 360 360 360 360 360 360 360 360 360 360 360 360 360 360 360 360 360 360 360 360 360 }(X> 360 360,485 $60 360 360 360 360 360 360 360 360 360