Noise muting switch for television receiver audio amplifier

摘要

An audio amplifier (10) comprises a decoupling capacitor (14) at one output (13) for separating a DC voltage (UDC) superimposed to the output signal (UO). To the audio signal output (15) is connected a parallel semiconductor charge carrier channel, whose conductivity is varied by a control voltage (US) for preventing interference voltages during switching-on and off. The charge carrier channel is formed by a collector-emitter path (C1-E1) of a first bipolar transistor (18), whose emitter (E1) is coupled to earth and whose base (B1) is coupled to control voltage via the emitter-collector path (E2-C2) of a second bipolar transistor (20) of complementary zone sequence w.r.t. the first transistor.