This circuit was obtained in an old documentation, but it is still current by the used components. The circuit must be powered by a 12 V regulated power source.
We found this circuit on Radio Electronics from July 1990. It triggers a relay with a touch of the...
These three circuits have different treble responses. We found them in the February 1970 issue of...
This photoelectric cell light relay was found in Radio Electronics magazine from April 1958. The...