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 is intended to reinforce old car radios, having been found in 1997. At that time,...
This oscillator found in Electronics Now of the 90s is of the Normally-Off type, being triggered...
This circuit was found in a Popular Electronics of the 90s. The operational amplifier admits...