- Published in issue 7/1996 on page 99
Signal-controlled switch II
This circuit is another variant of the switch described elsewhere in this issue. Its function is to switch off an audio system if there has been no audio input for five minutes. Its signal input is simply connected to the line output of the preamplifier or ahead of the volume control in the power amplifier. Its output energizes a relay with single contact to switch off the mains to the audio system.