This old 1 W audio amplifier transistor circuit is from a 1967 Japanese magazine. The transistors are germanium of the time and the type transformers found in similar equipment of the time.
This circuit works as a useful field meter for radio amateurs. We found it in documentation from...
The circuits below were found in amarican publication of the year 1958. The transistors are...
This circuit was found in a 1975 documentation. Current general-purpose transistors can be used,...