This circuit controls an external light that turns on at dusk and off in the morning. The circuit is from a Radio Electronics from October 1987.
We found this zener regulator in a 1978 radio amateur documentation. The operational can be...
This sensitive circuit was found in old documentation. The SCR can be any of the 106 series and...
This simple receiver was found in a book on transistors from 1954. The coil determines the...