burglar alarm

Table of Contents

List of tables 3
List of Figures 4
1Introduction 5
2 Circuit diagram 6
3 Circuit components 7
3.1 LDR 7
3.2 Resistors 8
3.2.1 Color code 8
3.3 IR LED 9
3.4 LED 11
3.5 OP-AMP 12
3.5.1 OP AMP LM 324 13
3.6 Transistor 15
3.6.1 Transistor 2N2222 15
3.7 SCR 16
3.7.1 SCR C106MG 18
C106MG 19
3.8V Battery 19
3.9 Photo diode 20
Principle of operation 21
3.9.1 IR Photo diode 21
3.10 Switches 22
3.11 Buzzer 23
3.11.1Mechanical buzzer 24
3.11.2 Electromechanical buzzer 24
3.11.3 Piezo buzzer 24
Uses 25
4 Working of circuit 26
5 Result 27
6 Applications 28
7 Advantages 28
8 Disadvantages 28
9 Conclusion 29
10 Future scope 29
Bibliography 30

List of tables

Table 1 Pin Description 14

List of Figures

Figure 1Intruder Alarm 6
Figure 2 Diode 7
Figure 3 Resistor 8
Figure 4IR LED 10
Figure 5 LED 11
Figure 6LM 324 13
Figure 7 Pin diagram 14
Figure 8 Transistor 16
Figure 9 SCR C106MG 18
Figure 10 9V Battery 20

1Introduction

Burglar alarm systems/Intruder alarm systems monitor the designated area or areas to detect the presence or suspicious elements and plays a crucial role in theft protection. It is one of the most reliable means to secure a house or a work place. The intruder alarm system consists of an array of sensors, a control panel, alerting system and interconnections. Sensors detect the intruders by many methods such as monitoring door and window contacts, by passive infrared motion detectors, ultrasound vibration, electric or magnetic fields or may communicate wirelessly. Intrusion alarm systems may also be combined with closed-circuit television surveillance systems to automatically record the activities of intruders and may interface to access control systems for electrically locked doors. An alarm is designed to alert the user to an intrusion. The work of the home security system begins with the sensors and motion detectors.
Alarm circuits are spread wide over the internet and some of them are