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 4-function, high-pass, low-pass, band-pass and rejector filter was found in French...
Passing between a light source and the sensor will trigger on the relay by a time interval...
This circuit was obtained in the publication 101 Electronics Projects of 1979. The circuit can be...