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 trips when a negative pulse is applied to its input or when the voltage drops below a...
This is an old 1988 circuit consisting of a timer or time control for exposing silk-screen arrays. The...
This circuit was taken from an old American documentation. It can be built with modern op amps. The...