This sophisticated remote field strength meter circuit was found in a 73 magazine for radio amateurs from the1990s. The circuit measures signals in the 1650 kHz range.
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...