With this circuit it is possible to tune an AM signal using a 5k potentiometer (4k7). The circuit was found in a publication from the 1980s and the PLL can be replaced by an equivalent one, with tests.
In the figure we have a simple signal tracer circuit to be coupled to the volume control of an AM...
This circuit was found in documentation from the 90s, using components from that time. The...
This circuit, obtained from old documentation, allows the recovery of sulfated batteries. The...