This small 1W turntable amplifier was found in the 1975 RCA tube manual. It is a commercial circuit at the time.
This circuit was found in a RCA documentation from 1977. The integrated circuit is uncommon today. It is...
This circuit is from 1990 documentation. It can be implemented with BC548 transistors instead of...
This circuit triggers a load that depends on the characteristics of the transistor when we touch...