This interesting multi-channel circuit was found in the August 1988 issue of Radio Electronics magazine. It monitors the signal from 4 sound channels simultaneously.
This circuit, when triggered, locks, and remains so until the source is switched off for a moment or...
With the values of the components indicated, this timer controls intervals from a few seconds to a...
This circuit with a few watts of power was found in the April 1995 issue of Electronics Now...