This circuit was found in a 1980s American documentation. The circuit is based on integrated CMOS 4001 that are common today. The load is a relay according to the power supply from 6 to 12 V.
This circuit for audio signals was found in the March 1990 Radio Electronics magazine. The circuit...
In the figure we have the way to implement a sinusoidal oscillator with the 4093 IC. The component...
Equivalent transistors, like the BC548 and BC558 pair can be used in this circuit that we find in an...