In the figure we have the typical circuit of a Baxandall tone control applied to an operational amplifier. The operational can be of any type.
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...