Approved by the FCC, this circuit was found in documentation from the 1980s. The circuit uses an unusual component today.
This ultra-simple meter uses an output transformer and a small speaker as a microphone. The...
The circuit presented was found in a 1988 documentation. It consists of an alarm siren that it...
This RS flip-flop uses two type 4N26 optical couplers and is characterized by the very high...