Found in American documentation from the 90s, this circuit uses a high voltage relay and has no grid isolation. The high values of R1 and R2 prevent the shock when it touches the sensors.
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...