In this blog we have given a simplified, more economical and easily understandable circuit of Burglar Alarm. This circuit comprises an electromagnet, reed switch and LDR. The circuit formed is very less complex and is easily understood by higher secondary school students. The main purpose of this work is that if these type of simpler circuits are made then engineering projects could reach school students and the standard of education will be improved.
The first burglar alarm was invented by Augustus Russell Pope. He issued the patent for the same on June 21, 1853. The circuit consisted of a tripwire that electrically powered a solenoid that struck a gong when it was set off. In 1905, the American Telephone and Telegraph Company purchased the Holmes business. Starting in the 1970s, a number of alarm systems came equipped with motion sensors. The twentieth century also saw major developments in alarm technology. These devices and improvements have lead to strength in home security technologies which can be trusted by all. Home security is a rapidly growing field, and there are new and improved burglar alarms popping up all the time. For the most part, these systems are all built around the same basic structure. A central control box monitors several motion detectors and perimeter guards and sounds an alarm when any of them are triggered.
Burglar alarms are automatic home monitoring devices to monitor and alert in case of a burglary attempt at residential, commercial and industrial. Burglar alarms are kept at such a place that when thief enters the house then a shadow will fall on the circuit. A small beam of light source is also needed to supply continuous signal to circuit. For best Light source, Laser is used.
There are several things a burglar alarm might do when it detects an intruder. In an advanced system, the control box will be wired to several different components. Typically, it will activate: a siren or other loud alarm noise, flashing outdoor lights, a telephone auto-dialer. Functions of the siren and lights: alert occupants and neighbors that someone has broken into the house, drive the intruder away, signal to police which house has been broken into. The telephone auto-dialer can dial the police directly, and play a pre-recorded message giving the address of the house and any other relevant information. This message will usually play over and over so that the police will still hear it even if the call is put on hold for some time. It can also dial the security company that installed the equipment. In this case, the control box can feed specific information about the intrusion — which circuits or motion detectors were activated, etc. The security company then relays this information to the police.
