The principles underlying radio communication (1922)
United States. National Bureau of Standards, Ould, Richard Sheldon, 1889-, United States. Army. Signal Corps · Washington, Govt. Print. Off. · leaf 152
struments this distance is about 0.003inch. The permanent magnet pulls the diaphragm toward thepole pieces a certain distance, which depends upon the flexi-bility of the diaphragm. The variations in the current in thereceiver windings, corresponding to the sound vibrations ofthe voice spoken into… … Fig. 93b.—Watch case telephone receiver. It is possible to use a telephone receiver as a transmitter.With a circuit containing only two identical sensitive telephonereceivers and no battery, the same instrument can be usedalternately as receiver and transmitter by the person at eachend of the line,…
Telegraph, Wireless · Radio
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