We found this circuit in a 1977 documentation. The National Semiconductor's LM380 is no longer easily found, but if used on this amplifier it provides excellent reproduction quality.
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...