Project report in design and construction of pull pin security alarm system incorporated with led lights for signaling

Abstract

Technology is a blessing to our modern life and has become part and parcel to our day to day life. It has made our life easier and comfortable by introducing better security systems than in the old traditional society. We cannot even think of a single day without safety, because it has a great impact in our socio-economic life. Besides this, an important issue has been risen throughout the whole world and that is the insecurity of portable devices. Therefore our main concern be-hind this project is to develop a security system for such devices using the 555 timer and condenser microphone intended for consumer applications. This project introduces a pull pin security alarm incorporated with LED lights which is affordable and user friendly. The system turns ON and OFF automatically when the pin is out of contact from the circuit and when it is in contact with the same circuit respectively. It makes an alarm inform of sound and gives LED lights which increases its sensitivity and adaptability. The user can make use of this circuit by attaching it to the potable device to be protected. All the circuit components involved in coming up with the system have been clearly discussed and these include; the 555 timers,BC547 transistors, capacitors, resistors, condenser MIC, loudspeaker and light emitting diode. The working of the circuit was tested and involved two steps ;Putting the contact pin in touch with the circuit and no sound and light was given off, secondly, removing the contact pin from the circuit and a loud sound was produced together with LED lights on the other hand. Hence the circuit which produces sound as an alarm and at the same time LED lights has been developed.