This circuit is intended to detect when current flows through the opening of a car door. The circuit fires the horn for 90 seconds. The FET can be the BF245 and the NPN transistors can be the BD135.
This circuit is intended to increase the width of a pulse. The circuit is TTL and can be used as a...
The first circuit, shown in the figure, generates a stepped signal whose frequency depends on the...
This circuit is from a 1968 documentation using one of the first integrated circuits available at the...