Strange phone wiring

[JoeJoe]

Wanted to move one the phone socket extensions today.

I remove the faceplate, and the wiring inside looked a bit strange.

In the house there is one master socket where the phone cable from the outside is connected with 3 further extensions hard wired to it. All the sockets around the house work fine. Photo of master socket is here:

Two of the extensions are wired on both ends as per usual - i.e. pins and wire colours, but the third one - the one I was looking at today is wired as follows:

At the master socket end: Pin2: White with Blue Pin5: Blue with White All other wires are cut.

On the extension socket end the wiring is as per this photo:

that this is also the socket used for ADSL and phone.

Is this right (I assume it is, as it works...)?

If I want to use a different face plate, will I have to connect all 4 cables as per the usual way?

[JoeJoe]

Oops! Master socket photos is here:

[Dave Liquorice]

See the thread entitled "Any experts on telephone wiring?" to save everyone saying the same things again. That extension faceplate with just the two wires presumably has bothe a normal telephone socket and ADSL socket on the face?

These days all you need is the pair with the line on connected at each socket the orange wiring can be left disconnected. Some older phones might not ring but will work otherwise.

[The Natural Philosopher]

Use of a master faceplate at each extension solves the ring problem.

Although too many is not strictly kosher as it loads the line up.

[JoeJoe]

Cheers, missed that one - and very helpful it is too!

Mine extension use a star topology, and it is going to be very difficult to change that without major work, so I am happy to continue to leave with it. The ADSL filter is connected to one of the extensions.

As advised there I now disconnected pins 3 and 4 on all sockets. Unfortunately I haven't noticed any change to the broadband speed as a result... (I used one of the online speed tests).

Thanks anyway.

[JoeJoe]

I assume that you refer to the socket connected at the end of the extension in question?

I am planning to replace it with a standard (i.e. on master) one.

[Peter Crosland]

You need to get BT/Openreach to fit a correct NTE5 master socket. That would enable you to isolate the interior wiring. This link tells you more.

Peter Crosland

[Andy Burns]

It looks he *has* one, but someone has swapped one of the extension sockets with the master one.

Since the wiring is only using pins 2/5 now (no problem so long as all phones still ring) it could be improved and put back closer to normal but undoing the swapping, leaving the extensions wired only as 2/5 on the blue pair from the back of the faceplate, and using the orange pair for a dedicated ADSL extension to wherever the master socket is currently ... use an 'RJ11' socket and one of the modified NTE2000 style faceplates from e.g. clarity.

That'll mean only one master socket, unlike the two currently in use, and one ADSL splitter unlike the several currently in use, so stands a decent chance of improving broadband speed.

[Dave Liquorice]

Nothing wrong with star provided the star is on the POTS side of the ADSL filter. I'd stick the (singular) ADSL filter at the center point of the POTS star and if it wasn't practical to have the ADSL modem plugged in there have a single pair from the unfiltered side of the filter to the modem.

You really need to look at what the sync speed is between your modem and the echange. This is probably available somewhere in the modems web interface, possibly under diagnostics.

An online speed test may well be limited by the BRAS rate (maximum rate at which BT will let your ISP feed your line). This BRAS is dynamic but can take a long time (up to 3 days) to increase after when the sync rate has increased. It'll get knocked back PDQ though!.

[JoeJoe]

Not sure I am following you...

Do you suggest replacing the current master socket (the centre of the star) with one of those socket with a built-in filter, and then use the orange/white pair to propagate the filtered signal to the extensions?

Also, what is the point of replacing the current (non-standard) master socket with one of those official BT master socket with NTE5 faceplate (apart from making it more legit)? I seem to remember a couple of years ago a branch fell on the wire in the street, and the BT guy who replaced it simply connected the new wire into the house into the (non-standard) master socket...

I am planning to remove the 2nd master socket - the one at the end of the extension in the photo, and replace with a standard socket.

[Andy Burns]

yes, remove the non-official master at the centre of the star (presume that's where the drop cable comes in)

put the NTE5 back there (presume it was originally there at one time)

Fit a faceplate ADSL filter to the NTE5, one of these modified versions makes it simpler and allows you to have a remote ADSL socket

from the 2/5 pins on the ADSL faceplate (using the blue pair) to all your extensions, leave pin3 disconnected, most phones don't need the separate ring signal, and it leaves you a spare pair for the ADSL extension.

Connect from the A/B pins on the ADSL faceplate (using the now spare orange pair) to an RJ11 socket for the router.

Precisely to make it more legit, you never know when you might get an arsey BT engineer turn up if you log a fault, might as well fix it up now, rather than later.

They won't all turn a blind eye.

All I can say is, that having used a single central ADSL faceplate on about a dozen friends/family installs, it ALWAYS improves the speed over a hotchpoth of master socket, extensions and microfilters that most people seem to accumulate.

[JoeJoe]

Right, I think I am with you now. Not a problem - I'll put the BT master socket where it should be then.

What if I want to have ADSL RJ11 socket for all the extensions? just in case I'll want to move the modem around the house? Can I replace the faceplate of all the extension sockets with one of those

, connect pins 2 and 5 as suggested to the master socket, and the the A & B to the A &B of the faceplates?

[Dave Liquorice]

The simple answer is you can't, at least not in a plug 'n play sense unless you are wililng to sacrifice some of your ADSL speed.

[JoeJoe]

What about using a single gang with 2 modules - one RJ45, one RJ11, for each extension socket?

[Andy Burns]

Can't see that it'd drop much speed, the ADSL side is a straight connection to the line, you've already got x,000 feet of cable between your house and the exchange, another few feet shouldn't hurt much

Should be ok, if you lose speed just disconnect the unused ones until you move stuff around again, presume you won't do it very often?

[JoeJoe]

Not at all. It is just that with the work involved in running the cables I would rather leave my options open in the future.

[JoeJoe]

I like this idea.

I intend to use Clarity's single gang, double faceplate with an RJ11 and an RJ45 modules. As I am already wiring for Ethernet to the same location, is it worth running another CAT5e cable for the RJ11 socket? Only reason for doing it is if it stands a chance of improving ADSL speed.

[Dave Liquorice]

sense

The trouble is that the POTS side needs to be filtered and the ADSL side unfiltered. So for each point you need to feed filtered and unfiltered. With your star topography each arm of the star that is unterminated will produce reflections and introduce noise onto the ADSL pair. If you just had a single pair to each extension you would need multiple filters. Both of these are not good for ADSL. You can shift things about by moving the ADSL faceplate and adjusting the wiring.

Not sure why you want an RJ11 and RJ45 faceplate, BT telephone plugs aren't RJ45.

[JoeJoe]

Makes sense. As the chance of moving the modem around in the future is pretty small I'll stick with your suggestion.

My mistake - I meant phone socket.

[JoeJoe]

Pressed send to early...

If I do choose to utilise one pair of the phone cable for ADSL to the modem, how do I go about terminating it, considering that I also need to use the phone pair? Use a BT phone socket module and a RJ11 module in the same face plate (e.g. from Clarity)?

Also, is there anything special about the Clarity master face plate, or is this

identical in terms of performance (at half the price)?