This circuit for very low frequencies was found in an American documentation from the 90's. Transistors are for general use and the frequency depends on C1 and C2.
This circuit acts on the dynamic range of an audio signal, which can be useful for recording,...
This is the conventional application of the UCN4202 to control a 12 V stepper motor with current...
Described in the December 1969 Radio Electronics magazine, this circuit is intended to supply the...