What's going on here

D-Dan · Apr 21, 2009, 19:14:40

DSL Connection

   Link Information

Uptime:   0 days, 19:25:39
Modulation:   G.992.1 annex A
Bandwidth (Up/Down) [kbps/kbps]:   448 / 7.200
Data Transferred (Sent/Received) [MB/MB]:   14,53 / 143,63
Output Power (Up/Down) [dBm]:   12,5 / 19,5
Line Attenuation (Up/Down) [dB]:   24,5 / 45,0
SN Margin (Up/Down) [dB]:   6,0 / 6,0
Vendor ID (Local/Remote):   TMMB / TSTC
Loss of Framing (Local/Remote):   0 / 0
Loss of Signal (Local/Remote):   1 / 0
Loss of Power (Local/Remote):   0 / 0
Loss of Link (Remote):   0
Error Seconds (Local/Remote):   4 / 0
FEC Errors (Up/Down):   0 / 70.500
CRC Errors (Up/Down):   0 / 173
HEC Errors (Up/Down):   0 / 163

Highlighted entries are relevant. I'm supposed to have 880 upstream and that upstream SNR is decidedly low. What would cause it?

Steve

Glenn · Apr 21, 2009, 19:17:29

No idea Steve, have you tried a reboot of the router to see if it connects at the correct rate?

D-Dan · Apr 21, 2009, 19:38:27

Was trying to avoid an evening reboot if I could with such good downstream stats, but I think I'll have to. Gonna try now.

Steve

D-Dan · Apr 21, 2009, 19:42:41

OK - rebooting got my upstream back to 832, though upstream SNR is still only 8. It's usually around 16 - 19. Why would there be so much upstream noise? I've never encountered this before.

Steve

Sebby · Apr 21, 2009, 23:09:34

I've seen this before, Steve. It's noise on the frequencies used by upstream. It's more rare as it's the downstream frequencies that are susceptible to noise to a greater extent, but it does happen from time to time.

g7pkf · Apr 22, 2009, 11:48:45

Ah i can possibly help on this one i had this problem for a short while.

turned out to be flourescent bulb (you know the ones that you replace a standard light bulb for to save electric)

It was new but a cheap "weve just made 3Billion profit" one.

replaced for normal bulb problem gone away, replaced with an osram flourescent problem still gone away.

found it by accident as it only caused a problem/ My snr went down dramatically when i was in workshop.

This is the sort of thing you need to be looking at i think.

Simon · Apr 22, 2009, 13:24:49

Wow, that's a good tip, Dean.

Rik · Apr 22, 2009, 14:46:42

I know ours can play havoc with the remote control for my Bose iPod dock. I feel that the Govt has been way too hasty in a rush to force us into using low-energy bulbs.

Tacitus · Apr 22, 2009, 15:47:17

I've been looking at re-routing some of my cables whilst I have some work done in the roof space - I'm in a bungalow. I had thought of running some of them through aluminium tube for additional shielding, although they are all twisted pair including the ADSL connection.

Rik · Apr 22, 2009, 15:56:22

I'm all for belt and braces, Tac.

Tacitus · Apr 22, 2009, 17:32:03

Quote from: Rik on Apr 22, 2009, 15:56:22
I'm all for belt and braces, Tac.

TBH Rik I was surprised how far the radiation from fluorescent bulbs extends.

Rik · Apr 22, 2009, 17:44:46

Me too, I'd not really experienced it with tubes, due to where they were used, it was the bulbs that really opened my eyes.

D-Dan · Apr 22, 2009, 20:35:53

As much as I'd like to be able to say "That's it", I got home tonight to find the power had been off today. Checked my stats and still have upstream SNR 8.0, with no lighting turned on at all. It's odd, since whatever it is doesn't affect downstream. I guess it is just frequencies, and probably external.

As long as the connection remains stable I won't be too concerned.

Steve

Baz · Apr 22, 2009, 20:49:54

when you say fluorescent bulb do you mean the strip ones, 5/6ft in length, or these new energy-saving-use-lesspower-last-forever jobbies

Rik · Apr 23, 2009, 08:14:28

Either, Baz.