This 5-tube hi-fi amplifier was found in an American publication from 1947; The output is in class B and the circuit uses a source with transformer.
This circuit, with adjusted sensitivity, can use common general-purpose transistors. The circuit is...
This circuit was found in a 1967 RCA documentation. The semiconductor components are from the...
This is the traditional configuration of na Astable Multivibrator using two NPN ttransistor....