More than a mobile phone

PROUD DISPLAY: B. Kalaivani demonstrating her invention. Photo: R. Ashok  

M. Balaganessin

Pudukottai student invents burglar alarm

PUDUKOTTAI: A wide range of features are now part of the mobile phone technology. Short messaging service, chat, call register, mobile camera and video come on the big list.

But, a student of The Raniar Government Girls' Higher Secondary School, Pudukottai, has culled out yet another use of the instrument - converting her cell phone into a burglar alarm. It is a simple circuit working on the principles of magnetic theory.

The accessories required are a mobile phone, a piece of wire and a couple of small bar magnets.

A Plus Two student, B. Kalaivani, took a cue for her device from a plastic alarm her father S. Babu bought at a local market.

"A telephone number is saved on the mobile phone which is connected to one of the magnets. When the door remains closed, the magnetic induction between the two bar magnets is active and the mobile phone is at rest. On the other hand, when the door is opened, the induction is disconnected and the phone gets activated, calling the number saved," explains Ms. Kalaivani. At a given time, four numbers can be saved, so that the alarm signals could be sent to four persons.

When the inmates are asleep or away from their houses, the signals are sure to alert them.

The device was the cynosure of all eyes at an exhibition organised at her school recently.