We found this circuit in a 1991s PE Hobbyst Handbook. The circuit fires 10 LEDs that can control incandescent lamps according to their maximum current.
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...