Extending BT Master Socket to RJ11 data only

memoriafuturi · Aug 21, 2021

Something simple, I think.... my understanding is that the BT master socket extension is unfiltered. Does this mean that I can run it to a RJ11 plate and plug my wifi router directly into the Rj11 socket? I think this is the case. I don't use any landline phones, so have no need for phone socket. Also, the master socket extension is labelled A&B. What Rj11 pins would I connect these to for the router? I've been told it should be 3&4.

Thanks for any tips/confirmation.

UNG · Aug 21, 2021

What type of BT master socket do you have as some do have the ADSL built in

For an extension you should connect to the plug in extension plate on 2 & 5 and on the RJ11 it would be 2 & 5

memoriafuturi · Aug 21, 2021

UNG said:
What type of BT master socket do you have as some do have the ADSL built in

For an extension you should connect to the plug in extension plate on 2 & 5 and on the RJ11 it would be 2 & 5

Hiya - thanks for the reply. I'm planning to change to a new one as mine is kind of old. Going to swap to 2019 BT Openreach Telephone Master Socket NTE5c MK2 & VDSL/ADSL Faceplate MK4. I was under the impressing that the master socket extension for ADSL was a&b? Though this description seems to say a&b but the image has 2&5. So you're saying just match the 2&5 on the master socket with the 2&5 on the RJ11 (I assume it wont work if you have the wrong way around?) and then I can plug my wifi router straight into the RJ11 without anything else and should be fine? Thanks again

freddo · Aug 22, 2021

memoriafuturi said:
I was under the impressing that the master socket extension for ADSL was a&b? Though this description seems to say a&b but the image has 2&5. So you're saying just match the 2&5 on the master socket with the 2&5 on the RJ11 (I assume it wont work if you have the wrong way around?) and then I can plug my wifi router straight into the RJ11 without anything else and should be fine? Thanks again

The outgoing ADSL terminals are marked A+B and are not shown on that website. The terminals 235 are filtered and for connecting telephones only. Connect to terminals 3&4 on the RJll socket

memoriafuturi · Aug 22, 2021

freddo said:
The outgoing ADSL terminals are marked A+B and are not shown on that website. The terminals 235 are filtered and for connecting telephones only. Connect to terminals 3&4 on the RJll socket

Thanks for this. This was what I thought was the case A->3 and B->4 but I've seen so much different information floating around??

freddo · Aug 22, 2021

A->4 (0V) B->3 (-48V) would be conventional but most modern phone stuff doesn't seem to care about polarity now.

memoriafuturi · Aug 26, 2021

freddo said:
A->4 (0V) B->3 (-48V) would be conventional but most modern phone stuff doesn't seem to care about polarity now.

So I've kind of done this but not working...

So, I have 2 extension cables that come out behind my master socket. One goes to each bedroom - but I'm not sure which goes to which, so I just connected both to the master socket extension A&B.

In the bedroom where I want to move the router there are also 2 extension cables where I'm trying to attach (one is from the master socket and the other goes to another location in the bedroom) and again I'm not sure which is which - So I attached both to the back of the RJ11 plate.

I did originally plan to test which cable went from the master socket to my new location and just attach this, but wasn't sure how I could check this. Most of the advice is to use a multimeter but the ends are a long way apart so can't get the multimeter to both ends.

I'm curious whether doing double wires connecting in both locations could be causing the problem? Would also be ideal, I guess, to check the cable isn't damaged, however, I don't think this is the case.

Thanks again for the help on this. Will be very happy if can get it resolved....

freddo · Aug 26, 2021

memoriafuturi said:
I did originally plan to test which cable went from the master socket to my new location and just attach this, but wasn't sure how I could check this. Most of the advice is to use a multimeter but the ends are a long way apart so can't get the multimeter to both ends.

Yes you need to test and should only have the 1 cable connected, having cables going all over the place can reduce broadband speeds.

To test you can disconnect the wires, then with the cable you want to find, connect 2 cores together. Use your multimeter set to continuity at the other end to find the cable with the 2 cores connected together. There are other ways to find a cable but this is one simple way.

When you have found the correct cable, connect it up and reassemble the master point. Remember when the front phone part of the master socket is removed it also disconnects the A & B terminals in the part still attached to the wall. Plug it all back in and give the router 5 or so minutes to connect. If it is still not working go to the RJ11 , with your meter set to DC volts you should be able to measure ~48V at terminals 3&4.

memoriafuturi · Aug 28, 2021

freddo said:
Yes you need to test and should only have the 1 cable connected, having cables going all over the place can reduce broadband speeds.

To test you can disconnect the wires, then with the cable you want to find, connect 2 cores together. Use your multimeter set to continuity at the other end to find the cable with the 2 cores connected together. There are other ways to find a cable but this is one simple way.

When you have found the correct cable, connect it up and reassemble the master point. Remember when the front phone part of the master socket is removed it also disconnects the A & B terminals in the part still attached to the wall. Plug it all back in and give the router 5 or so minutes to connect. If it is still not working go to the RJ11 , with your meter set to DC volts you should be able to measure ~48V at terminals 3&4.

Thanks. Really good idea re connecting the wires at one end and measuring the other. Don't know why didn't think of this!!

So, I'm not having any luck finding the active wire. I guess I must have a break somewhere. Will keep testing until I find it, just trying not to cut too much wire away or wont have any left. Little strange as wire doesn't appear to be broken, but seems quite easy to snap, so guess need to just keep trying until find a good connection. At least this feels like a plan to work through....

memoriafuturi · Aug 28, 2021

I think I might have to admit defeat on this project. I've done a lot of continuity testing on the different wires and can't get any connection at all. I've tried pulling the ends of the wires quite hard to see if broken, and they don't appear to be. But I just can't seem to get any success on the continuity at all. Kind of at a loss. I guess maybe the wires have been damages somewhere inside the wall? Seems a little surprising, but can't think of another explanation for no continuity at all....