This circuit turns off a relay after a time determined by C1. The circuit was found in the December 1974 Radio Electronics magazine. The relay is rated according to the supply voltage.
Found in Mullard's 1960s transistor manual, this circuit has components that depend on the...
This signal injector uses a single integrated circuit as an oscillator, producing rectangular...
This second amplifier is based on the integrated LM108 and has a differential input. The resistor...