This circuit was found in an American 1980s documentation. The transistorized step is the receiver's last IF and the diode is the receiver's existing detector.
Found in Popular Electronics from the 90's, this circuit makes use of components from the time. |...
This circuit for the logic control of the 555 in a power supply was found in the October 1989...
In this circuit, a light-sensitive SCR or Light Activated SCR determines the operation of an...