DESIGN AND CONSTRUCTION OF AN INTRUDER DETECTION AND SECURITY SYSTEM

Abstract

The intruder detection and security system here designed and constructed is essentially a three (3) trigger zone and a five (5) circuit module electronic system with the primary objective of securing life and property by detecting the operation of an intruder and achieving apprehension before the intruder is aware of being lJlonitored. This security system can find use in any ... . enclosed area or building. The first zone is sound or vibratibn triggered, this is triggered when the intruder tries to break in through an entrance. The second is triggered by depressing switches embedded in an electric mat; this happens immediately:.the intruder steps into the building. The third is triggered when the intruder in an attempt to proceed further into other sections of the house interrupts an infrared beam. According to design, the triggering of the first, second and third zones ;s indicated by three (3)light emitting diodes-(LED), radiating yellow, green and red pilot lights respectively. In addition, the triggering of these zones generates a tone that is amplified and transmitted by an audio- radio frequency transmitter system that transmits the tone at a modulated frequency. Hence, the alarm can be received remotely by security officers with receivers tuned to that frequency and within the range of transmission. After testing, the triggering of the individual zones was indicated by a lighting of each of the LED's sequentially as expected. Also, after powering the transmitter, with a pure DC source, a power of about 3.45W was found to be generated in the transmitter by calculation and a signal of 96MHz was received clearly over a range of about 150meters.