The circuit shown, with the printed circuit board, was found in an article in the June 1990 issue of Radio Electronics magazine. Integrated circuits must be equipped with heat sinks.
This version of the circuit is from 2000, using a source of negative voltage that allows to obtain...
This somewhat complex circuit was found in the May 1984 issue of Radio Electronics magazine. The...
This basic circuit is from an old documentation. The relay must be 50 mA maximum and must have a...