This 4-transistor amplifier can work from 4.5 or 6 V power supplies. We found it in a Mullard transistors manual from 1960. The transistors are from the time.
This elementary receiver with only one germanium transistor was found in a Japanese publication from the...
The National Semiconductor LM377 integrated circuit consists of a low power audio amplifier. This...
This astable multivibrator has an emitter coupling between the transistors. The circuit is from...