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Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

Mipblip — Sun, 30 Aug 2026 07:05:00 GMT

I'm trying to wire up my broadband connection and have run into an old GPO Terminal 52A junction box that I'd like to reconnect to a modern master socket (NTE5).

The incoming cable has solid-coloured wires, and I have a standard modern cable running from the master socket (with the blue/white, orange/white, and green/white ).

I'm trying to reconnect for broadband, as some idiot didn’t take a photo before dismantling. I'm unsure which incoming wire matches which internal wire on this old terminal block.

I've attached photos of the current setup and my attempt so far. Any advice on the correct pairing or cleanest way to wire this up would be greatly appreciated!

Thanks!

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

Colin_London — Sun, 30 Aug 2026 11:57:10 GMT

Can’t really give advice other than you should not be tampering with this wiring. Anything the exchange side of the NTE5 is only for Openreach to touch.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

WSH — Sun, 30 Aug 2026 12:09:35 GMT

@Colin_London True, but Openreach don't care unless you cause them a problem.

@Mipblip I would suggest a much bigger picture of that junction box would be useful, as that picture doesn't really show any detail.

@Colin_London By the way, I don't know whether you went back to that thread or not, but I did answer your query as to what a Smart Hub Pro was.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

imjolly — Sun, 30 Aug 2026 13:01:04 GMT

where are the 2 cables exiting the wall coming from? 1 incoming openreach and other connecting to an extension socket somewhere? is the other end of lose cable connected to the NTE5 ? there are 2 terminals with 2 wires connected blue and orange suggesting they are the live connection

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

Mipblip — Sun, 30 Aug 2026 20:00:43 GMT

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

Mipblip — Sun, 30 Aug 2026 20:12:29 GMT

I can only follow one cable which goes into the roof and then presumably overhead across the road to pole. As for the second cable I’ve no idea.

thanks Michael

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

imjolly — Sun, 30 Aug 2026 21:16:37 GMT

Are there any other phone boxes in the home in other rooms? Is the lose cable connected to the NTE5 possibly the main connections A and B?

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

pddco — Mon, 31 Aug 2026 00:01:16 GMT

Have you still got an analogue phone service? If so you could temporarily connect a pair of wires to the NTE5. Plug a phone into the test socket of the NTE 5. And then listen for dial tone while you connect/ touch the bared copper ends of the pair of wires to the terminal block to identify the incoming line. It’ll probably be the blue and orange wires.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

Mipblip — Mon, 31 Aug 2026 05:14:12 GMT

No other sockets or cables.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

Mipblip — Mon, 31 Aug 2026 05:16:51 GMT

Unfortunately no phone, as far as I can see this the only cable that enters the house.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

36ULW — Mon, 31 Aug 2026 07:26:03 GMT

Blue/Orange is Pair One and Green/Brown is Pair Two.

Pair One is normally the default pair to put the line on but it could be on Pair Two.

Also looks like it’s Star Wired, that’ll affect your Sync Speed.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

pddco — Mon, 31 Aug 2026 09:46:34 GMT

If you’ve got a broadband service you could try temporarily connecting the wires from your NTE5 to the Blue and Orange pair and see if the hub gets connected. If not then try the Green/ Brown pair. At least then you’ve identified which pair the service is on. You’d then need to find out which cable is the incoming one. So if it was the blue/orange pair you’d need to separate the wires and connect to each pair separately and see if you get service. Trouble is though as @36ULW has said there may be other star wired connections which’ll mess up your Sync speed. So before making the connection permanent you really need to trace the route of the incoming cable ( which’ll be black or perhaps grey) from the pole to another Block terminal where it changes to the internal cream coloured cable and see where it goes from there.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

WSH — Mon, 31 Aug 2026 13:26:08 GMT

@Mipblip Let me clarify a couple of points before I make any suggestions.

You already had an NTE5 in place, but you disconnected it and now don’t know which wires to reconnect. If that is the case the NTE5 only has two connections for the incoming line, A & B. Is it those two you are trying to reconnect to that junction box? (The wires at the bottom of the picture show 4 bare wires. There should only be 2 if you are using that to connect an incoming line to the NTE5).
Those lines coming through the wall, (or at least one of them), is the incoming line?

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

pddco — Mon, 31 Aug 2026 17:14:08 GMT

It’s likely that the incoming cable will have the blue and orange connected to the outer two terminals, with its green and brown spare wrapped in a loop.

While the outgoing ( extension) wiring will have its blue, orange and green ( bell wire) terminated.

But of course as @WSH says, more detail would be most welcome..

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

WSH — Mon, 31 Aug 2026 17:52:24 GMT

Assuming I've understood what the OP is doing correctly, I was going to recommend this website:

https://telephonesuk.org.uk/wiring-info/

I’d look particularly at the second paragraph under “NTE5 Line-box wiring instructions”, about a quarter of the page down. If you refer back to the table at the top of the page, you'll see that pin 2 is the B leg and pin 5 is the A leg on the NTE5.

Re: Help reconnecting legacy GPO Terminal 52A box to modern master socket (NTE5).

Mipblip — Mon, 31 Aug 2026 19:29:28 GMT

I’m getting connected tomorrow, so will give it a go.