yarwell, yes, you have described it correctly.

RobertoS, thanks, I will do as you suggest; will be tomorrow morning.

Just switched on after several hours away - thinkbroadband speedtest = 61 Kbps (yes, really!), BT produced 490 Kbps. Don't think I'll be doing much surfing tonight.

OK, I did as RobertoS suggested.

TB speedtest result before doing anything = 0.7 Mbps. It's usually better morning than evening.
Router =
ADSL Link Downstream Upstream
Connection Speed 1792 kbps 448 kbps
Line Attenuation 63.5 db 31.5 db
Noise Margin 10.4 db 10.0 db

I unplugged everything.

Discovered I had forgotten one socket from the list posted above. It's first in line on (1) so this bit should read
1) cable (via outside of house) to downstairs socket; then to upstairs socket (the one connected to router); and on to an extension from this one.
This wiring was installed for me a few years ago by a friendly telecomms engineer (not employed by BT). All three sockets had no T3 connection. All three have a small cylindrical object inside at the top (as in my master but smaller).

The wiring to the junction box, master and extension (2 above) is older; I guess original (house built 1982). 2a does look like a master. Both had T3 connected; I have now removed these.

Rebooted router, reconnected ADSL cable + filter, restarted pc.
Router =
ADSL Link Downstream Upstream
Connection Speed 2368 kbps 448 kbps
Line Attenuation 63.5 db 31.5 db
Noise Margin 9.3 db 11.0 db

TB = 1.43 Mbps. I have see this level just twice before in the last 6 weeks, both morning.
BT = 1.48

Plugged 3 things (2 sky boxes + 1 phone with 3 digital cordless handsets) back in and took a router reading after each one. Router stats exactly the same after each one.

What do I conclude?

I would conclude that the wiring was dropping the speed from

Connection Speed 2368 kbps 448 kbps

to

Connection Speed 1792 kbps 448 kbps

The former will give you a 2M IP profile. Did you restart the router or its ADSL modem after each change - you only see the full effect of a wiring change if the modem reconnects to the DSLAM under the new conditions.

ETA: I wasn't clear if you removed the excess master sockets and wiring or just took the wire off T3 ?

Edited by yarwell (Thu 10-Jan-13 11:09:36)

In reply to a post by veryslow:

This wiring was installed for me a few years ago by a friendly telecomms engineer (not employed by BT). All three sockets had no T3 connection. All three have a small cylindrical object inside at the top (as in my master but smaller).

What do I conclude?

I will leave Roberto to comment on the stats &c but have one comment to make.

COWBOY ...

In reply to a post by MHC:

In reply to a post by veryslow:

This wiring was installed for me a few years ago by a friendly telecomms engineer (not employed by BT). All three sockets had no T3 connection. All three have a small cylindrical object inside at the top (as in my master but smaller).

What do I conclude?

I will leave Roberto to comment on the stats &c but have one comment to make.

COWBOY ...

RobertoS hasn't time to think about the stats right now, though wouldn't disagree with yarwell's post.

Your final word there is exactly what I would say about the chap who did the wiring. There's only one way to go with that, and that's replace the lot. I wouldn't even guarantee the wires themselves are suitable.

Dare we ask for the colours of the wire and which ones are connected to which terminals!

Well we could ask veryslow .

OK, back for a minute.

I misread your latest post at first. I think we have a good result there.

Re my approval of yarwell's post and my previous one, I don't think I do quite agree about rebooting the router after each item was reconnected. That might trigger a noise margin rise by the DLM unless the reboots had a decent time gap between them. IT might have been best when you did it, but I wouldn't bother redoing it, seeing as the noise margin didn't change.

The wiring certainly is a mess, but how much improvement you could get by having it all redone is debatable. Probably not enough to justify the expense for the moment.

I think we should leave it as is for now and see if that noise margin is lowered by the system in 10-14 days time. So unless anything goes downhill before then I recommend leaving the router on until the end of that.

If the DLM does lower it, it normally causes a re-sync anyway, often overnight.

If you find that has happened, a single daytime reboot with stats taken immediately before and after like you just did is what to do. (No need to disconnect anything).

I would be wary of the Sky boxes. Particularly if they are old ones. They can cause trouble. A few recommendations.

Do a quiet line test now. 17070, option 2. It should be effectively silent. If not, unplug the Sky boxes and try again. (I'm ssuming they are powered up).

If they are off, check the stats before and after switching them on for the first time after now.

Thanks again for all the helpful comments.

On the wiring, it was/is not practical to run the new cabling from the BT master socket. May I ask, out of ignorance again, what causes the concern? RobertoS said that the T3 connection was redundant nowadays, so T3 would not have been connected? I will happily identify colours and terminal connections tomorrow and post again.

RobertoS said

I think we should leave it as is for now and see if that noise margin is lowered by the system in 10-14 days time. So unless anything goes downhill before then I recommend leaving the router on until the end of that.

I will certainly do that and let you know.

I don't understand

Do a quiet line test now. 17070, option 2. It should be effectively silent.

. The sky boxes are 14 months and 2 months old respectively. And they were on at the time of testing.

I've just done speedtests. TB = 0.23. BT = 1.05. 2 minute video clip on BBC news website stops to reload every 15 seconds - so no improvement in real performance.

In reply to a post by veryslow:

On the wiring, it was/is not practical to run the new cabling from the BT master socket. May I ask, out of ignorance again, what causes the concern? RobertoS said that the T3 connection was redundant nowadays, so T3 would not have been connected? I will happily identify colours and terminal connections tomorrow and post again.

From your description of capacitors in every location, it suggests that they are all masters. Every master has a 1.8 uF capacitor and 470k resistor in series across A to B legs. That can put additional loading on both voice and ADSL/VDSL signals. If the installer did not understand the need to have just one master then it is likely he did not understand the need to use the right cable. Telephony cable is made up of 2 or 3 twisted pairs (with different twists) and that help in the rejection of electrical noise. Unfortunately some installers use Burglar Alarm cable because it is cheaper - not twisted and also finer. That results in possible intermittent connections and noise pick up. The noise may not be an issue on the voice side (but it can be) however it will almost certainly have an effect on ADSL/VDSL. Just by the colours it is possible to tell the type of cable and if it is telephony grade that a pair has been used.