This 1967 Ferranti circuit uses company components. These transistors can be replaced by modern equivalents. The sensor is an LDR.
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...