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

[36ULW]

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.

[pddco]

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. 

[WSH]

@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?

[pddco]

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..

[WSH]

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.

[Mipblip]

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