This circuit is from the time when cars used contact breakers. This 80's version measures the dwell angle of the contact breaker for dwell adjustment using an era integrated circuit, the LM3917.
This circuit is from old documentation but can be applied to modern equivalent components. The...
In the figure we have a simple signal tracer circuit to be coupled to the volume control of an AM...
This signal amplifier for ATV in the 427 to 439 MHz band was found in a magazine 73 for radio...