Radio broadcast .. (1922-30)

348 Radio Broadcast WOAH Palmetto Radio Corp Charleston, S. C. WOAK Collins Hardware Co Frankfort, Ky. WOAL William E. Woods Webster Grove, Mo. WOAN James D. Vaughan Lawrenceburg, Tenn. WOAP Kalamazoo College Kalamazoo, Michigan WOAQ Portsmouth Radio Ass'n Portsmouth, Va. WOAR Henry P. Lundskow Kenosha, Wisconsin WOAS Bailey's Radio Shop Middletown, Conn. WOAT Boyd Martell Hamp Wilmington, Delaware WOAU Sowder Boiling Piano Company Evansville, Indiana WOAW Woodmen of the World Omaha, Nebraska WOAX Franklyn J. Wolff Trenton, New Jersey WOAY John M. Wilder ..-.-' Birmingham, Ala. WOAZ Penick Hughes Co Stanford, Texas WPAC Donaldson Radio Co Okmulgee, Okla. WPAG Central Radio Co., Inc Independence, Mo. WPAH Wisconsin Dept. of Markets Waupaca, Wisconsin WPAJ Doolittle Radio Corporation New Haven, Conn. WPAK North. Dakota Agricultural College North Dakota WPAP Theodore S. Phillips Winchester, Ky. WPAQ General Sales & Engr. Co Frostburg, Md. WPAR R. A. Ward Beloit, Kansas WPAT Saint Patrick's Cathedral El Paso, Texas WPAU Concordia College Moorhead, Minn. WQAB Southwest Missouri State Teachers' College . Springfield, Mo. WQAK Appel-Higley Electric Co Dubuque, Iowa WQAL Cole County Tel. & Tel Co Mattoon, 111. WRAA Rice Institute Houston, Texas WRAN Black Hawk Electric Company Waterloo, Iowa WSAJ Grove City College Grove City, Pa. WTAC Penn Traffic Co . Johnstown, Pa. WTAU Ruegy Battery & Elect. Co. " . . Tecumseh, Neb. WWAD Wright & Wright, Inc Philadelphia, Pa. The Grid QUESTIONS AND ANSWERS The Grid is a Question and Answer Department maintained especially for the radio amateurs. Full answers will be given wherever possible. In answering questions, those of a like nature will be grouped together and answered by one article. Every effort will be made to keep the answers simple and direct, yet fully self-explanatory. Questions should be addressed to Editor, ''The Grid," Radio Broadcast, Garden City, N. Y. The letter containing the questions should have the full name and address of the writer and also his station call letter, if he has one. Names, however, will not be published. LOOSE COUPLERS How does a loose coupler work without any connection between tbe primary and secondary? I have a set consisting of a loose coupler, variable condenser, crystal detector, fixed condenser and Turney )ooo-ohm phones. I get no results at all. Could you help locate my trouble? My antenna is of the T type; one end is about fifty feet high and the other end sixty feet high. I enclose my hookup. — J. B., NEW YORK CITY. IN a general way, electricity is transferred from the primary of a loose coupler to the secondary by means of a phenomenon called induction. Whenever electricity traverses a circuit, such as from the antenna, through the coupler primary to the ground, magnetic lines of force, similar to those surrounding the poles of a horseshoe magnet, spread out from the conductor, and reproduce magnetically every fluctuation of the current. When these lines of force cut an adjacent conductor, such as the secondary of the coupler, they "generate" another current which exactly follows the variations of the magncctic field, and therefore duplicates, excepting in strength (there is a small loss) the antenna current. Large generators in power houses operate on this principle, and are nothing more than machines which pass a dense flux, at a high speed, through windings from which the current is drawn. However, in a loose coupler, induction alone does not explain the transference of energy from primary to secondary, for it is doubtful that with the low inductance (due to the few turns of wire and the absence of an iron core), and the comparatively great distance that often separates the