We found this 6-tube amplifier in a 1947 publication. It is a Public Address amplifier with excellent performance using triodes on the output.
This small commercial radio for the MW band with germanium transistors was found in Japanese...
This circuit is from 1992 documentation. The transistor can be a TIP42 with a good heat sink for...
This speaker overload protection circuit was found in Radio Electronics from the 1980s. The...