Old house telephone wiring

[dutts]

Hi,

Moved into a 40s/50s house with some interesting phone wiring I'm trying to unpick.

The main phone wire comes in through the front door into an old PTO labelled junction box (screw-down terminals with metal bars connecting them together) above the door.

From this one cable runs down the door and along the skirting to a "master socket" (BT Openreach branded with dedicated filtered ADSL socket).

Another cable runs from the junction box straight up through the ceiling to a socket in the bedroom, where a further cable runs up a door frame through the ceiling into the loft to drop down in a cavity wall which is wired into *another* Bt Openreach branded twin master socket in the study.

Crude diagram:

--- Junction box -- Hall master socket
|
Bedroom socket
|
Study master socket

There is only a single pair of wires connected throughout; the Blue and Orange as they appear in the junction box.

I've got our ADSL router plugged into the socket in the study so I can have a wired connection to my computer for working from home. As expected with all the wiring I am not getting the best ADSL signal I could but out of the three sockets, this is the best location for house wifi coverage.

I would like to retain the sockets in the hall and study but happy to lose the one in the bedroom what would be the best way to try to improve / modernise this?

Am I right in saying that modern installs have BT wiring up to a proper master socket, with any secondary sockets wired from the removable front plate of that master socket allowing you to isolate the house extension wiring from the BT service? If that's the case should my old PTO junction box be a master socket? (despite beiing above my front door)?

I was thinking that replacing the PTO junction box with a modern punch down junction box would be a good start.

Rich

 

[rsgaz]

Am I right in saying that modern installs have BT wiring up to a proper master socket, with any secondary sockets wired from the removable front plate of that master socket allowing you to isolate the house extension wiring from the BT service?

Yes.

If that's the case should my old PTO junction box be a master socket?

No, the hall socket is the master.

what would be the best way to try to improve / modernise this?

Unfortunately it all sounds pretty standard, so there won't be much you can do. Check that all the cables are solid copper cores, twisted pair and not stranded wire.

replacing the PTO junction box with a modern punch down junction box would be a good start.

Incoming lines aren't always the correct thickness for IDC, you need to check. If they are older thicker ones, then you best you can do is a screw terminal to IDC box, such as Block Terminal No. 80A. I'm not sure it will improve anything.

 

[dutts]

No, the hall socket is the master.
Unfortunately, it all sounds pretty standard, so there won't be much you can do. Check that all the cables are solid copper cores, twisted pair and not stranded wire.

Even though the extensions are from the junction box and not from the master socket?

Incoming lines aren't always the correct thickness for IDC, you need to check. If they are older thicker ones, then you best you can do is a screw terminal to IDC box, such as Block Terminal No. 80A. I'm not sure it will improve anything.

From the photos I took they look the same thickness as the ones they're connected to but I'll double-check, thanks. On the potential improvement, I assumed that removing a pair of joints in the decades-old junction box with an IDC junction might help?

 

[rsgaz]

Even though the extensions are from the junction box and not from the master socket?

Oh, sorry, I misread your ASCII art. Yeah, that's not ideal.

I assumed that removing a pair of joints in the decades-old junction box with an IDC junction might help?

It's still two joins though. If you incoming line is very old, it won't even be twisted pair. Getting BT in to replace that would be the best bet at improving speed. Have you got a picture of that? You say it's blue and orange, which isn't standard dropwire colours.

 

[dutts]

Oh, sorry, I misread your ASCII art. Yeah, that's not ideal.
It's still two joins though. If you incoming line is very old, it won't even be twisted pair. Getting BT in to replace that would be the best bet at improving speed. Have you got a picture of that? You say it's blue and orange, which isn't standard dropwire colours.

Yes I have, here's the junction box:

The bottom left wire comes in from outside, where it runs around the house as a thick black cable and drops down into my driveway, the orange and blue wires from that are the only ones connected.
The top left wire goes upstairs to the socket in my bedroom, which also has connected to it a further extension up through the loft into the study (where my current ADSL router is).
The right hand wire goes to the socket in the hallway (incoming blue to brown and incoming orange to green).

It looks like it's been well used over the years, there are bits of wire under most of the terminals. It appears that some other colour convention has been used for the internal wiring; incoming blue to brown and incoming orange to green for the onward connections.

 

[rsgaz]

The bottom left wire comes in from outside, where it runs around the house as a thick black cable

Where does that black cable turn into the white cable shown? Another junction box? Outside maybe?

It looks like cheaply manufactured cable, the colours are wrong and it's very hard to tell if they are twisted pairs at all. They shouldn't have been untwisted like that.

 

[Diver Fred]

The internal wiring is done in the 'old' 4 wire (used 1960's thru 1990's). The incoming cable is also internal 4 wire - it looks like you have another junction with external (Underground >UG<) cable. The 'active' pair of wires in that UG cable would be green and black. think whoever did your wiring tried to copy that convention with the internal wire hence the use of green & brown. Internal colour convention in that era is Aleg - Blue, Bleg - orange, 3rd wire green (earth for shared service or bell extention), 4th wire - brown (bell on shared service). The 'pairs' are not twisted.

So to improve your existing Broadband service the first step is to swop the 'distant' Master socket for an extention socket - that will remove the 2nd capacitor and resistor for the bell circuit.
The next step is re-wire your internal wiring with modern BT1302 cable as follows: blue/white - Aleg, white/blue - Bleg, orange/white - Bell.

 

[dutts]

Thank you both, I'll track down the other junction box between here and the outside. it wasn't until I studied my own pictures that I realised that the "outside" cable coming into this has white insulation, whereas the cable running around my house is black so they must be joined somewhere, I suspect in the back of the cupboards in my porch.

So just to confirm when I find this other junction I should expect to find green and black wires in there? And just so I don't confuse anyone in future which is the A leg and which is the B leg on those?

 

[rsgaz]

I should expect to find green and black wires in there?

Hopefully you will find normal "dropwire". Which has two twisted pairs and 3 yellow steel strength members. Don't touch the strength members, they are very sharp.

The first pair is actually orange and white, the spare pair is green and black.

The A leg is white (or black in the other pair).