This circuit, suggested by an Electronics World of 1969, keeps a blinking LED for a while when a power outage occurs. Time depends on capacitor C1.
This circuit was found in a 1964 documentation. It shows how to achieve automatic gain control for...
We found this circuit in the June 1991 issue of Radio Electronics magazine. The circuit can be...
This circuit drives an old tape recorder when an audio signal is received. The circuit is...