The practical telephone handbook and guide to the telephonic exchange (1906)
Poole, Joseph · New York, Macmillan Co. · leaf 83
DBOOK diaphragm vibrates, its polished surface curves, and so causesthe amount of light which falls on the selenium cell to cor-respondingly vary, and its resistance to vary proportionately,the sound being thus reproduced in the receiver. Fig. 44gives a sketch of the arrangement. In Tainters… … iRROft Fig. 44.—Arrangement of Photophone These are instances of Wireless Telephony, of which muchhas been heard lately,- but of which no very practicableapplication has yet been made. The later systems are similarto the Photophone, but more elaborated. Dolbear in 1880 invented a Condenser receiver…
Telephone
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