DESIGN CONSTRUCTION AND TESTING OF A RAPID LIGHT CHANGE PROXIMITY DETECTOR SWITCH

Abstract

This project work concentrates on the desig n. construction and testing of a rapid light change proximity detector switch. The switch uses a photocell as its sensor. The sensed signal is sent to an amplifier. The resultant signal from this circuit is rectified. The rectified version of this signal is used to bias a transistor. This causes a relay contact to make. Hence triggering the appropriate circuit into conduction. The circuit could be used in intruder alarm systems or in certain other application where proximity detection is required. VI