Making telephone wire / adsl wire.

  rastaman25 11:03 22 Jul 2010

Hi all,

I need to run a cable from my main BT box outside, to the upper floor of my house. When it is there, I would like it to return to a secondary BT Box.

However, I do not want to intrude on any wiring that BT themselves have done in the main box, and as such, I wish the extension to begin with a normal telephone plug.

This would then run up the wire, and end in the secondary BT box.

The hole that will be put through the wall will only just be wide enough for the cable, without the attachments on the end, which means that I must manufacture the cable myself.

Obviously I will need the bt telephone style plug, the extension cable, bt telephone secondary socket, and a pair of crimpers.

Could anyone please advise me on where in the UK I could buy these items, and how to go about connecting them?

I failed to mention earlier in my post that this line will be used primarily for my ADSL conection, but telephone connectivity being retained is desirable. Therefore, I think I need at least a CAT5 standard cable?

Thanks in advance,

  onthelimit 11:13 22 Jul 2010

CAT5 cable is for the ethernet connection - ordinary telephone cable will be suitable for this extension. Maplins a good source for plugs and cable click here

  rastaman25 11:15 22 Jul 2010

Hi, thanks for the quick response.

I'm after the best quality connection that can be acheived without hard wiring into the BT main box, so could you recommend which cable I could use?

Thanks again.

  rastaman25 11:29 22 Jul 2010


I've just had a quick conversation with my Dad, and we've decided that in reality, as our phones are wireless and will continue to be so, an actual telephone socket will not be required.

In this case, would it be possible to run the cable in this order:

BT Master Socket -> Microfilter -> use the "computer" output, and run this style cable outside and in -> end in a socket?

I'm not sure if this is the best way of doing it, nor what the type of cable I would require is called!

Sorry to change my mind, but in reality, telephones nowadays are nearly all cordless!


  onthelimit 12:06 22 Jul 2010

Yes, that would be much better than a long run of telephone extension. Maplins a good source of Cat5 cable and the RJ45 plugs. You will need a proper crimping tool forthese, though. Some tips click here

  rastaman25 12:23 22 Jul 2010


RJ45 plugs? These are ethernet plugs?

I only need a plug at one end of the cable to connect to a normal ADSL microfilter, so that will be an RJ11 plug, and at the other end, it will connect directly to an RJ11 faceplate.

The home Router will then connect to this faceplate, and in turn, to the PC via the ethernet cable, which is an RJ45.

Forgive me for not understanding, but I don't think I need RJ45?

So, I would start the cable with this : click here

and end with this at the other end:
click here

What sort of cable will I need? 4 wire?

Thanks again,


  onthelimit 12:43 22 Jul 2010

No, the router will have to go next to the master socket with a filter, RJ45 (Ethernet) cable to the upstairs. It can be terminated at a wall socket click here then the PC plugs into that

  rastaman25 12:51 22 Jul 2010

A diagram of my phone system is here :

click here

The right hand side is the current setup, as I previously had issues with noise on the setup. It is working over a 15/20m telephone extension, and acheiving speeds of over 5mb, so this clearly works well.

The reason I need the router upstairs is due to the house - the walls are thick, and the signal will not reach the far ends of the house (the house is extremley tall and wide).


  onthelimit 13:10 22 Jul 2010

If you want the router upstairs, then your layout will have to be as discussed originally and as shown in your diagram. I.E, telephone extension from master socket, through the wall, up to the upper story, to a socket, then microfilter and router. An alternative in difficult houses is to use home plugs - click here as an example

  rastaman25 13:26 22 Jul 2010


I don't understand how this wouldn't work. All I am doing is literally extending the RJ11 cable that is already coming from the Router to downstairs.

The only difference is, is that instead of going through a telephone cable, it would go through an RJ11 cable instead, as shown here:

click here

Could you please explain exactly why this wouldn't work? I simply cannot see any reason it wouldnt?


  onthelimit 13:40 22 Jul 2010

'instead of going througha telephone cable, it would go through an RJ11 cable instead'

I think you are getting confused - RJ 11 is for telephone. CAT 5 is for Ethernet. Therefore you can't use RJ 11 to plug into the ADSL socket on a microfilter, but you can do as shown in your latest diagram if you use Ethernet and RJ 45 plugs/socket.

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