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.
Found in a 1965 General Electric Hobby Manual, this timer was originally created to operate with...
Found in a 90’s Radio Electronics magazine, this circuit uses a component from the time, difficult...
Only one LED is turned on when S1 and S2 are pressed. The LED that will be on is just the...