Radio, miracle of the 20th century ... a story of human achievement that stands unrivalled in the history of humanity, together with a colorful portrayal, giving a broad, general view of the whole subject of wireless telegraph and telephone and its marvelous development (1922)
Drinker, Frederick E. [from old catalog], Lewis, James G., [from old catalog] joint author · [Philadelphia, Printed by National publishing co.] · leaf 232
ct on the telephone receiver as alow frequency alternating current. This low frequencycurrent corresponds exactly to the impulses sent out bythe transmitting station and the audible signals are copiedas the message. They may, of course, be in code or radio-telephone conversations. The foregoing… … NO CONNECTIONCOUPLED COlIN-VARIABLE COUPLINGDETECTORGALVANOMETE GAP. PLAIN —• #_ GAP. QUENCHED ||||||||L_ GROUND -^j=F nouctor ORFttRRl. mD^o^^07^ INDUCTOKEY. RESISTOR VARIABLERESISTOR
Radio
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