For signals up to about 500 kHz modulated in amplitude and transmitted by the power network, the figure shows the receiver. The circuit is from a Radio Electronics from February 1989.
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...