Gpo bt20/4

Maliplex · 12-10-2009, 14:20

Hi
I would appreciate some advice about my current BT wiring. We have what I believe is called a General Post Office BT20/4 junction box which was screwed to the inside of our front door frame, next to where the thick black cable arrives into the house (It is currently off the wall while we decorate). A very thin wire (see photo) then runs several feet into the hall where the NTE5 socket is located. This wire is pretty old and mangled with several layers of paint.

I rang BT and explained that our junction box dates back to 1950s and asked if we were entitiled to an upgrade. They said that it would cost me Â£140 unless I could show that the line is faulty. They ran a line test and said that it is fine. However, I'm not convinced that the broadband speed we're getting is as good as it might be.

So, my questions are:

Is it worth pushing for a newer junction box or is that just aesthetics?
Is the cable between the junction box and the main socket of acceptable standard?
Is there anything I can do to improve this for myself e.g replacing the thin cable with something with better shielding?

(I am testing the broadband speeds from the test socket, thus eliminating any extension cables)

Any advice/help much appreciated.

Maliplex · 12-10-2009, 14:24

Sorry, forgot the photo

Graham M · 12-10-2009, 14:40

By the looks of it it's simply aesthetics, all you've got there is the equivalent of a choc bloc connector in a plastic case, there doesn't appear to be anything clever going on there, simply the connection between 2 wires

Maliplex · 12-10-2009, 15:50

Hi Graham
Thanks for your reassurance abou the junction box - not pretty, but doing its job.

How about the cable between the junction box and the main socket? It is just like an ordinary extension cable, so could this be causing problems? If so, what could I replace it with?

Thanks

Matthew · 12-10-2009, 18:33

You cant touch any of the wiring that comes into the house up to the master socket, thats all BT's responsability.

Graham M · 12-10-2009, 18:50

What speed are you getting and how far away from the exchange are you?

Maliplex · 13-10-2009, 00:31

Quote:

Originally Posted by Graham M

What speed are you getting and how far away from the exchange are you?

Hi Graham
We're 1.8km from the exchange and the speed this morning was 3267Kbps using www.speedtester.bt.com.

Thanks

**Chris** · 13-10-2009, 00:36

Quote:

Originally Posted by Matthew

You cant touch any of the wiring that comes into the house up to the master socket, thats all BT's responsability.

Quite correct, although asking subscribers for Â£140 to come and do non-fault work on it is kind of asking the subscribers to say "stuff you then, I'll do it myself", isn't it ...

danielf · 13-10-2009, 00:49

Quote:

Originally Posted by Maliplex

Hi Graham
We're 1.8km from the exchange and the speed this morning was 3267Kbps using www.speedtester.bt.com.

Thanks

Distance from the exchange is not a very good way of assessing this. Ideally, you should log into your modem to find out what your line attenuation and Signal to Noise Ratio (SNR) are. Unfortunately, since I've never used BT for broadband, I don't know what the login details for the home hub are.

Also, it rather depends on what package you are on. Presumably, the maximum speed for your package is 8mbps?

Maliplex · 13-10-2009, 17:18

Quote:

Originally Posted by danielf

Distance from the exchange is not a very good way of assessing this. Ideally, you should log into your modem to find out what your line attenuation and Signal to Noise Ratio (SNR) are. Unfortunately, since I've never used BT for broadband, I don't know what the login details for the home hub are.

Also, it rather depends on what package you are on. Presumably, the maximum speed for your package is 8mbps?

Sorry, took a while to find out how to do this on a BT HomeHub. You have to go into Settings/Advanced Settings/Broadband/ADSL...

Noise margin (Down/Up) 16.1 dB / 11.3 dB
Line attenuation (Down/Up) 40.4 dB / 19.4 dB
Output power (Down/Up) 6.2 dBm / 1.3 dBm

The Download speed today has dropped to 1144Kbps, which is worrying because I fitted a BT Broadband Accelerator yesterday. Perhaps I should remove it again?

danielf · 13-10-2009, 18:00

It's been a while since I've been on ADSL max (which I presume you are on), so I don't really recall what realistic speeds are.

There's a speed calculator based on attenuation here:

http://www.kitz.co.uk/adsl/max_speed_calc.php

My impression however is that it is somewhat optimistic. But, you should definitely get faster speeds than the 1mb plus a bit you are getting now. I'd see what happens when you remove that 'accelerator'.

What is your sync speed btw?