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Think of it as a DIY home security system: if something distrubs a chosen location, you will know because your mobile phone will be rung.
Thanks again to our sister site Design News for this Gadget Freak, which involves an intrusion detection system.
Basically, it is a home alarm system that calls you whenever an event is triggered, whether a door or window is opened, or a panic button is pressed, etc.
The construction cost for the security circuit should be less than £20, but you will also need a PIC programmer to load the program into the microcontroller.Thanks again to our sister site Design News for this Gadget Freak, which involves an intrusion detection system.
Basically, it is a home alarm system that calls you whenever an event is triggered, whether a door or window is opened, or a panic button is pressed, etc.
You can set it up to indicate intrusion into a door, window, office or pool. It can also connect to a panic button. The circuit includes a small PIC microcontroller, an assembly program and a handful of other parts that can be designed to detect the interruption of a switch closure or the connection of a panic button. When the circuit is tripped, the gadget dials your number and indicates what device has been triggered.
Describing the circuit operation, Bill writes:
In operation, the switch closure is detected on pin 7 of the processor which activates the reed relay and takes the line off-hook for 3 seconds to establish the dial tone. The processor then dials the number by opening and closing the relay a number of times for each digit. When dialing is complete, the processor waits 3 seconds and then transmits a steady tone of about 300Hz for 30 seconds through the modem transformer. The call is then terminated and the processor waits for the switch to open before resetting.Get the full Build Instructions
Parts List
| Amt | Part Description | |
| 1 | PIC 16F628 Microcontroller | |
| 1 | 5V Reed Relay | |
| 1 | 470O Resistor | |
| 1 | 680O Resistor | |
| 2 | 330O Resistor | |
| 2 | 10K Resistors | |
| 1 | Small Signal Diode | |
| 1 | Red LED | |
| Additional parts required: | ||
| 1 Modem Transformer | ||
| 1 5V Wall Transformer | ||
Apparently, you can download a free Integrated Development Environment - a free assember for PIC micros - from www.microchip.com
Check out, too, Bill's own web page.
Comments (1)
Nice idea, but the legality of connecting it to the POTS in the UK would be suspect.....
Interfacing it to a mobile phone would solve that but would be another project in its own right!
Posted by Chris | June 24, 2009 1:13 PM
Posted on June 24, 2009 13:13