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 334
307 is varied so that the variation in amplitude follows iden-tically the amplitude and frequency of the sound wave.This is shown by the heavy line in B of figure 46. Thisline, together with lower inclosing line, is called theenvelop of the radio wave. Note that the upper andlower inclosing lines… … 7b source_ of UndampedO Haves n rectified current is similar to the heavy line of the en-velop. This is necessarily so as the rectified telephonecurrent does not follow the change in each individualradio frequency oscillation, but follows the change in theamplitude of these oscillations. This…
Radio
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