Wireless Telephony
Since wireless telegraphy has become so successful, it is but natural that wireless telephony should follow, just as the telephone followed the telegraph. In the ordinary wire telephone a transmitter is employed which varies the intensity of the electric current in the wire in direct ratio to the changes in the intensity of the sound waves set up by the human voice. All the undulations and tones of the voice are, therefore, transformed into complicated electric currents which, in passing through the telephone receiver, cause the diaphragm of the receiver to vibrate in unison with these complex currents, thereby reproducing articulate speech.
The high-frequency oscillations employed in wireless telegraphy are so rapid that the human ear cannot detect their presence in a telephone receiver. Therefore it is plain that if means be employed to vary the intensity of these high-frequency oscillations by a telephone transmitter actuated by the human voice, the received waves may be made to so operate a telephone receiver connected to a regular wireless detector, that articulate speech may be reproduced in the telephone receiver.
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