Cellular burglar alarm? Schematics anywhere?

[nonzero]

I would like to know if it is possible to create a portable burglar alarm. Something along the lines of a device that will dial a phone number once it is triggered.

The dialout could be via a cellular or landline and the detector could be an IR sensor or reed switch/magnet setup.

Does anyone have an idea on how to make this or a schematic.


Thanks

 

[panic mode]

Get manual for PC modem (must be *external* modem) and check it out.
It is easily programed with anything that has serial port. It can store number to be dialed etc. and the size is portable enough.
It should not be big deal to connect sensor directly to it but of course
much nicer solution is to use MCU for brain power.

 

[samcheetah]

why do u want the burglar alarm to be portable. usually burgular alarms are fixed in one place. if u want to have a small solution use a microcontroller. there is a burgular alarm project in the April 2002 issue of EPE. it uses a PIC16F877 microcontroller. u can connect it to a dialer, and when there is an intrusion the dialer will be activated.

if u live in the UK and have to follow the regulations strictly u would also like to see the project in the April 2001 issue of EPE

 

[Electronic Prototype]

For a wireless connection, you can use a GSM product such as Siemens TC35i. To report an alarm to another handphone, you will need to read and familiarize yourself with the AT command sets from the manual.

 

[tansis]

For a no frills and simple solution to this problem...

Take one old pre-paid mobile phone (with some credit on), enter the number you wish to call to raise an alarm and assign it to a specific digit key for "speed-dial" mode , then just connect a pair of wires from the keypad to the sensor switch / relay. As long as the recipient does not answer the call the credit is never used.

One of the uk electronics magazines did an article last year on GSM modules with a remote control project, EPE or Elektor i think.


Portable burglar alarms may seem a bit strange to some, however they are an incredibly common item in the military, thousands of them were dropped along the Laos / Vietnam border for instance.