This 6-transistor radio was sold in Japan in the 1960s. The super-heterodyne circuit for the OM band was powered by ordinary batteries.
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...