This 1-transistor circuit for currents up to 50 mA was found in the August 1974 Radio Electronics magazine. The transformer is 50 to 200 mA.
September 2017 - The new LDOs of STMIcroelectrinics LDLN025 for currents up to 250 mA and 1.5 to...
We found this circuit, which should only be used with incandescent lamps. In the Motorola Linear...
This version operates in the opposite way to the previous one, triggering when light falls on the...