This is a diagram of a 1970s reel or tape recorder. It is an Italian Geloso recorder, quite popular at the time. The circuit is a reference for equipment recovery.
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...