This two-year-80s circuit consists of a solution for a small portable recorder powered by cells, as it was used at the time. The circuit can serve as a reference for the recovery of old equipment.
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...