Welcome to this simple page on how to detect your phone line being cut and with the help of the GSM network Notifying you of the problem.
If you would like to see the unit in operational mode then click here
Why I designed and built this unit is down to the amount of crime around the world also the amount of phone line cutting that goes on before a crime is committed you could look at the unit as a early warning system.
In most countries around the world criminals cut your phone line to stop any form of communications like auto dialers communicating with a base station or your self before they break in to your premises.
Now I wanted to build a simple but portable PSTN (public switched telephone network) line cut detector unit that can be taken and connected to any phone line also I want to be notified of the line being cut by a GSM signal on my cell phone.
Now unlike a professional unit my simple idea would not upset people with a loud sounding bell or siren going off it will only send a cell phone signal to you even a criminal would not know a silent alarm was activated you don't even need a security system.
Most criminals cut phone lines long before they try and get in to your home, shop, factory or what ever they may cut the lines and wait for some time to see if the police or security guards turn up to investigate this is giving you time to get your home, shop, factory or organization checked before any damage is done.
The reason criminals cut your phone line is if they see an alarm system on your premises you may have a silent alarm that will send a signal when they enter into your premises or if you don't have an alarm system they will just cut the phone lines just incase some one reports them by using the PTSN phone network.
On this idea you will need some basic electronic skills, Also I have uploaded the finished unit on to my You Tube account to let you see the unit working.
Now the top circuit board is very simple you will have to build your self and the diagram for the first circuit is below.
Please note all if not most of the components used in this design can be got from www.bitbox.co.uk
To order the IFR510 in the United States of America Click here for radio shack.
To order the IFR 510 in the United Kingdom Click here and go down the list till you see it.
Now if you want the DATA sheet for the IFR 510 Click here.
The photo above is by Bill Bowden I used this idea in my own design as it is simple to follow and the drawing has been done as I don't have CAD on my computer CAD stands for (Computer Aided Design).
You may like to try the circuit above before buying the timer below after you finish building the top circuit connect it to your phone line and phone your home and see if the unit switches the relay with the hand set on hook.
If the unit switches the rely when the hand set is on hook then you can build or buy the ready built unit below
The good thing about using a simple timer is in case the power just dropped out for a short time and came back on again before the timer ran out and activated the cell phone.
Now the little circuit below is of a simple timer circuit by quasar electronics at time of writing you can visit there site here to order the timer circuit in kit form or ready built just click on the photo below..
Now if your green circuit is working ok then click the link below.
On the next page we will look at connecting every thing up and modifying the cell phone.