This circuit was found in the December 1976 issue of Radio Electronics magazine. The circuit includes a powerful pulsating siren. It is activated by courtesy light switches and other sensors.
This circuit was found in a 1980s US publication. There may be some difficulty in obtaining the...
The circuit shown is from the Motorola Linear Databook of 1990. In the example, the components are for the...
Ideal for benchtop use, this dual-band circuit was obtained from the 1995 Electronics Now...