This circuit uses a transistor to trigger the alarm from a low quiescent current sensor. The relay is 12 V. The circuit is from Radio Electronics magazine, April 1975.
This circuit was used to reinforce radio signals for listening on the phone, making it possible to listen...
This synthesizer circuit was found in a Radio Electronics magazine from May 1983. The circuit uses...
The circuit that gave rise to this configuration was found in a magazine of the 1980s with the...