We found this sophisticated meter circuit in an article in Radio Electronics magazine from June 1959. The article taught how to assemble it. Transistors are common types at the time.
To a 16-0hm load, this amplifier provides a power of 10 W. We found this circuit in a Motorola...
This distortion circuit was found in an American publication from 1970. It can be assembled with...
This configuration was found in an English magazine from 1965. It is valid for any junction FET. The...