Motion Detector Light Alarm Circuit Diagram

This is the simple Motion Detector Light Alarm Circuit Diagram. This circuit is very sensitive and can be placed in a room to detect the movement of a person up to 2 metres from the unit.The circuit is basically a high-gain amplifier (made up of the first three transistors) that is turned on by the LDR or photo Darlington transistor. The  third transistor charges the 100u via a diode and this delivers turn-on voltage for the oscillator.  The LDR has equal sensitivity to the photo transistor in this circuit.

Motion Detector Light Alarm Circuit Diagram