This old automotive circuit was found in an August 1971 Radio Electronics magazine article. The transistor is a Darlington transistor rated for the wattage of the bulb.
This well-known configuration that appears elsewhere on the site is from an English documentation. In it,...
We found this simple operating tester 741 in a European publication in 1991. The circuit...
Found in Radio Electronics, this circuit doubles the voltage of the 117V power grid to activate...