Telephone transceiver with amplified microphone and speaker
作者： Andre Deluegue
DOI:
关键词:
摘要: An amplified loudspeaker and microphone are connected to a telephone transmission network by coupling including induction coil having center-tapped primary winding. The output of superimposed modulation amplifier associated with the is applied center-tap winding input differential across secondary
lens.org 参考文章(3)
Rudolf Streit, Telephone sub-stations including transistors ,(1962)
Kaelin Pierre, Substation circuit with loudspeaker ,(1950)
Gabriele F Cerofolini, Loudspeaking telephone employing transistors ,(1957)