This circuit uses a photocell as sensor and a sensitive relay according the power supply voltage. Sensivity is adjusted by the trimmer potentiometer and the transistors are germanium types since the project was found in an old 1958´s magazine.
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This circuit uses a photocell as sensor and a sensitive relay according the power supply voltage. Sensivity is adjusted by the trimmer potentiometer and the transistors are germanium types since the project was found in an old 1958´s magazine.