New to IDNet & BT Wiring Query

[AlanM]

Just migrated from F2S last Friday and the migration could not have been easier or have gone better. I signed up on the Monday evening and on Tuesday morning got an e-mail saying I should be migrated by 6PM on the Friday. As it happened, the migration was completed around 03:15 (not that I was around at that time to notice!)

Now that I'm on a MAX service, I've been reading the FAQ's and various posts etc. to try to ensure that all my cabling is up to scratch as I have a long / poor quality line.
I've ordered an NTE5 Filtered Faceplate and a shielded RJ11 cable and they should arrive this week hopefully.
One thing that I'm not sure about though, is the BT cabling between where the underground cable comes up and my NTE5 Master Socket.
Hopefully you can view the attached pics and see what I mean.

The cable between the BT66B Box and the Master Socket is a thick, grey, 2-Core Flat cable. It's crimped onto the thin cores in the underground cable. You can see the Orange "Gel-Filled?" crimps at the top of the picture. The cable then enters the house through an air brick, runs under the floors and pops up under the stairs where it connects to the Master Socket on terminals A & B.
Given the frequencies ADSL uses, is this not acting like a large aerial?
Should this not really consist of twisted-pairs to help reduce interference from the ring-main etc.?

As this cable belongs to BT, I can't touch it, but does anyone else think this may be causing me problems?

Sorry for the long post.

Regards,

Al...

[attachment deleted by admin]

[Lance]

Welcome to the forum!

I guess it's quite possible that it will be picking up noise, but apart from paying Bt what will undoubtably be a large sum, i'm not sure what can be done about it. If you think it is causing a fault on your line then support can get the line tested. It might be an idea to speak to them and see what they say.

[Rik]

Hi Alan

Welcome to the forum.

Your wiring follows fairly standard BT practice, undoubtedly it was put in without thought to ADSL, probably before ADSL had been thought of.

I think the first thing to establish is whether you have a problem, the biggest source of noise pickup is usually from internal wiring, in particular the ring wire. Get everything you can deal with sorted, and see what your figures are like, particularly the d/s sync speed and noise margin. If it looks like they are causing you problems, then follow Lance's advice and contact support to get the line tested. Bear in mind that BT are not obliged to provide ADSL, so they are unlikely to spend a lot of money re-wiring the house for marginal gain - it's much more likely that they will do the work if you have a major problem.

Keep us posted.

[AlanM]

Lance, Rik,
Thanks for the replies. I really just wanted an idea as to whether or not this 2-core flat cable was a typical BT install. It's been like that since we bought the house in '88 and I hadn't really given it that much thought before the recent switch to Max.

I'm running RouterStats and monitoring the Noise margin etc. Before Max, it was anything from 1 to about 12dB. Since migrating, it's been pretty well fixed at 6dB but with quite a few instances where it drops. This morning was the worst yet where it basically sat between 0 and 1 for about 3 hours before jumping back up to 6dB. A couple more blips since then as well but mostly a solid 6dB since.

I've done the "quiet test" and heard nothing on the line but I must try it again if I can catch it when the noise margin is down.

I'll hopefully get the filtered faceplate and shielded RJ11 cable in this weekend and see if that makes any difference. Fingers crossed.