This commercial signal follower was found in a 1967 Japanese magazine. It uses germanium transistors and provides a speaker output without the need for a transformer.
MCP19124/5 Contains Independent Voltage and Current Control Loops Plus a Full Suite of...
This circuit is designed to control static loads fed by direct voltage. The circuit is from...
This circuit is from an American 1964 documentation. Transistors of the time are used, but modern...