This circuit was found in a publication in the 1980s. Modern equivalent components can be used. The source must be isolated. The circuit includes an oscillator.
We found this circuit in the October 1992 Radio Electronics magazine. The frequency is given by C1...
This conventional LED flasher circuit has a configurable multivibrator configuration with PNP...
This extremely slow circuit produces one pulse per month and can be used in a timer. We found it...