We found this circuit in the May 1996 Electronics Now magazine. The relay must have a voltage according to the circuit power supply and a trigger current of no more than 50 mA.
January 2017 - Mouser Electronics is announcing the availability of the new OptoMOS® CPC1010N...
This circuit is from the Motorola Linear Databook of 1990 and can be implemented with other...
The gated oscillator in the figure bellow tums on when a “0" Iogic Ievel is applied to its input....