We found this circuit in a 1963 Radio Electronics. It can be used for remote control. The frequency depends on the coil and the power is supplied by a single battery.
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...