This car alarm was obtained in a Signetics documentation from the 1980s. The circuit uses the 555 and has a pulsed output to activate a relay that controls the horn. The sensors are parallel connected.
This simple very low power circuit can be used in a battery powered infrared tone trigger. We...
This circuit came out in a Modern Electronics from June 1990. In it we have a low frequency...
This article is from an old publication by A. Fanzeres. With the advent of the Nuclear Era for...