This power control was found in a 1968 power circuit manual. The SCRs are according to the power of the controlled load.
This circuit was found in the used integrated circuit manufacturer's manual. The table beside the...
This circuit is from a 1973 documentation, using germanium transistors common at the time. The...
This simple tester was found in a Popular Electronics from the 90s. The circuit is powered by two 9 V...