How to self install DSL if you have an alarm [Guide]

This question comes up constantly so I have written this guide and attached diagram to use the simplest tools and equipment available to the average DIYer. I am an alarm engineer ex Phonewatch infact and have modified lots of lines for DSL and while this isn't the way I would do it professionally nor is it the way eircom would do it either it is basically the same. But it allows the average joe who doesn't have specialist tools or the proper network termination unit that an engineer would use for this task to get up and running and save themselves some money.

There is an attached jpeg showing a standard no alarm connected setup followed by a diagram showing you how phonewatch and other alarm companies connect your alarm to your phone to give you an idea how your alarm interacts / affects your phoneline as you can see there is no great science to it.

The last diagram might look scary at first but take the time to study it and see how everything connects together, it's really not that hard and I think should be within the grasp of most people here.

The diagram it'self show the parts "blown out" (for clarity) from one another but you can install everything neatly side by side or even better enclose everything in a small project box like you can get from maplins.
Before you do this modification have a good long think about where to put everything remembering you can do the modification at any point along the phoneline before it reaches the alarm connections for instance if you have a newer house with an external white phone junction box then the eircom master junction box is located in there making it the ideal place to neatly conceal your work.
One final point when you get your self install kit try it out before doing this mod as alot of people find that DSL works fine through their alarm anyway.

Now down to Business/

The modifaction is really straight forward, your phoneline works on a single pair of wires from the exchange what you need to do is cut this pair before the junction box and install a small phone socket on each cut end, the small ones with the stick pad on the bottom and the pry off lid are perfect for this.

You should have two phone sockets and each end of the phone line that you cut one end of the phone wire has your dial tone the other is still connected to your house phones. Now strip each end of the phone wire and pick out the pair eircom are using for your line you can check which colours they are by opening the eircom juction box and looking at the colours of the two wires that are connected in there.

Open up both of your new phone sockets and you will see four screw terminals you only need two of these and it's almost always the terminals with the red and green wires attached. Now with your phoneline pair of wires with the conductor exposed attach one wire to each terminal in the socket (it doesn't matter which way around they are) Now do the same with the other end of the cut phoneline using the same colour wires as before. you should now have the phoneline which you cut with a phone socket on each cut end.

Before going any further plug a phone into the socket on the wire coming from the street you should have a clear dial tone on this, the other socket will still be dead since it's only connected to your house, next step connect both sockets together using a normal phone lead with a jack on both ends now make sure all your house phones are working again. If not proceed no further and check your connections against the diagram. When you have your phones working again you can go ahead and plug in your DSL splitter into your new master socket and then plug the other socket going to your house phones into the phone side of the splitter, again verify your phones are working corectly if so you can go ahead and plug your modem into the DSL side of the splitter which hopefully should sync up. The DSL splitter may be some distance from your computer so you may need a long extension lead to go between your modem and the splitter, how you do this is up to you.

Remember to take your time and plan everything out first if you are a novice in this area it might be an idea to photograph or sketch the existing connections before you start incase you cant get it working and need to put it back the way it was also it's worth noting that if your phone rings when you are working on the line you might experience a very small electric shock don't worry it's not enough to harm you I get them all the time, but if you want you can divert all incoming calls before you start.

Lastly although this is a really simple job neither myself or boards.ie will take any resonsablity if you fuxer yourself or anything up although I am happy to help anyone who needs it via PM or email.

Warning: Make sure your alarm is still capable of dialing out afterward either by getting it serviced or by just setting it off after contacting your monitoring company first.

One of the mods might Sticky this.