Burglar Alarm System using TSOP IR Sensor, NE555 and LM311
Burglar alarm system using IR is a simple project which can be easily completed in 3 or 4 hours. System will have a transmitter as well as a sensor. Transmitter will transmit infra red rays continuously at a particular frequency. Frequency of generated rays can be easily adjusted by adjusting the potentiometer. System will also have a sensor which will sense IR rays. If the sensor is receiving IR rays, buzzer in the sensor system will not produce sound. Otherwise, buzzer will produce sound. Transmitter and receiver should be arranged in such a way that sensor will always receive IR rays and hence buzzer will not produce sound. If anyone block IR rays, sensor will not receive IR rays and hence buzzer will produce sound. Thus, we could sense the presence of thieves in the room.
Video demonstration of the same is shown below.