This circuit was found in a 90’s Electronic Engineering. The signal is sinusoidal with the frequency given by the non-value components that form the resonant network.
This circuit is from a 1976 Motorola CMOS manual. It can be implemented with modern Darlingtons like...
In the figure we have the way of modulating or controlling the frequency of a relaxation...
The purpose of this circuit is to monitor the operation of an alternator in cars with a 12 V...