ADSL Sync problems

Hi,

My line seems to be having some stability issues lately which I have reported to Eclipse and they are sending a BT engineer round tomorrow but I just wanted to see if there was anything else I can test to make sure I do not get charged.

The line gets a different sync speed every time it reconnects, between 1000-2700kpbs. I've disconnected all the extensions and the phone, replaced the router (DG834G) and also the filter.

It only seems to happen during the day - Eclipse can see that, so it may only happen under load.

From the router:

System Up Time 2 days 03:17:34
Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN PPPoA 5839 7065 0 1164 11018 00:10:10
LAN 100M/Full 986154 1140796 0 1334 886 2 days 03:17:13
WLAN 11M/54M 330190 153903 0 1853 42 2 days 03:17:34


ADSL Link Downstream Upstream
Connection Speed 1216 kbps 448 kbps
Line Attenuation 55.0 db 31.5 db
Noise Margin 21.0 db 21 db

At the moment, the phone is disconnected as I say but if I start downloading something and call the line from my mobile, a lot of the time the line will lose sync.

Any advice would be greatly received.

some kind of noisy joint on the line I suspect. If you had rebooted the speed would go up and the margin down and at 55 dB attenuation 2M should easily be possible.

So the router is connected to the master socket with no extensions present ?

After a reboot:
System Up Time 00:02:17
Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN PPPoA 322 301 0 407 777 00:01:37
LAN 100M/Full 578 659 0 1580 818 00:01:56
WLAN 11M/54M 82 0 0 130 0 00:02:17


ADSL Link Downstream Upstream
Connection Speed 2144 kbps 448 kbps
Line Attenuation 55.0 db 31.5 db
Noise Margin 14.0 db 21 db


Yes that is correct, the DG834G is connected to the master socket and there are no extensions attached either inside or outside the socket. I've also unplugged the phone, changed the router and the filter so the only thing plugged in at the moment is this router.

EDIT:
After posting this, I carried out the same test as before and started off a couple of downloads and called the line from my mobile.
The noise margin changed as follows (Downstream/Upstream):

13/21
6/21
15.5/21
-7/21

Then the router lost sync and after about a minute, it reconnected with the following stats:

System Up Time 00:11:12
Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN PPPoA 660 583 0 577 1184 00:02:38
LAN 100M/Full 7447 7463 0 8817 1501 00:10:51
WLAN 11M/54M 522 0 0 214 0 00:11:12


ADSL Link Downstream Upstream
Connection Speed 2048 kbps 448 kbps
Line Attenuation 55.0 db 31.5 db
Noise Margin 15.0 db 21 db

Edited by deleted (Mon 19-Jul-10 13:46:26)

as expected

Cheers for the reply.

So you agree this looks like a physical problem with the line rather than my equipment?

The most likely cause will be a high resistance fault on the line. The engineer should be running a 'pair quality test' using their Hawk, or possibly an Exfo or JDSU tester. The results *should* highlight a disparity in the ohms reading between the A and the B legs. Use of the TRD function should help them locate, and fix the fault.
Don't forget to tell the engineer about the use of the phone causing a drop in sync. They should be able to duplicate this using there test equipment. If you are lucky, and the engineer has enough time, ask them to ring BT wholesale and get the target snr rest to 6 or 9.

Good luck.