In the figure we have a stereo decoder from the 70's with pilot lamp for signal indication. The circuit employs a component of the time, which is uncommon today.
This configuration from a 1976 technical documentation shows how to use a varicap in a direct...
This circuit is from Radio Electronics. The magazine no more exists, but the circuit can be...
The purpose of this circuit is to cut the peaks of a sinusoidal signal so that it is close to a...