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Unstable noise today!

bigben
Grafter
Posts: 55
Thanks: 1
Registered: 04-01-2009

Unstable noise today!

all tho my target SNR is 14 to 15 it is normally rock solid though out the day.Until today.
 
Does anyone know what could be causing this.
My exchange is currently RED but surely that wouldn't cause this? 
11 REPLIES
James
Grafter
Posts: 21,036
Registered: 04-04-2007

Re: Unstable noise today!

Nope, it won't be your exchange contention.
It's going to be actual line conditions.  Do you hear static when you pick up your telephone?  Any work going on at your exchange that you're aware of?
bigben
Grafter
Posts: 55
Thanks: 1
Registered: 04-01-2009

Re: Unstable noise today!

I couldn't hear any noise on the line ,i am  now plugged into the test socket to see if that make any difference  .
its been stable  for the last 45mins in that socket.
scootie
Grafter
Posts: 4,799
Registered: 03-11-2007

Re: Unstable noise today!

any phone extension wiring coming out your master socket?
bigben
Grafter
Posts: 55
Thanks: 1
Registered: 04-01-2009

Re: Unstable noise today!

jim:quote
yes there is an extension but nothing is used on it.
Even being plugged into the master socket the connection has just   dropped again .noise went from 15db 8db 0db then re synced at  previous SNR and speed.(460Cool
James
Grafter
Posts: 21,036
Registered: 04-04-2007

Re: Unstable noise today!

Might be worth asking your telephony supplier to run a check on your l;ine and see if they are able to identify any issues on your line.
bigben
Grafter
Posts: 55
Thanks: 1
Registered: 04-01-2009

Re: Unstable noise today!

jim:quote
Have just spoken to BT and they have done two line test.
They say as the condition is not affecting the quality of the telephone (there tests showed no fault) i should go back to my ISP. 
James
Grafter
Posts: 21,036
Registered: 04-04-2007

Re: Unstable noise today!

They say that a lot Smiley
I'm hopeful that it's just over a brief period of time.  Would you mind giving it 24-48 hours and see if the line automatically stabilises?
There's a chance it could be your router or filter too.
bigben
Grafter
Posts: 55
Thanks: 1
Registered: 04-01-2009

Re: Unstable noise today!

[jim:quote]
My router is Dlink 2640b which i have found to be very good .
Router is plugged into main socket with one phone .(Dlink filter)
Sure i will keep routerstats running for a day or so to see whats happening .
bigben
Grafter
Posts: 55
Thanks: 1
Registered: 04-01-2009

Re: Unstable noise today!

Every thing had seemed to have been steady with 150 hours up time(all tho routerstats never dropped below 14db SNR sync 4000)
But today (12/2/09)the router  had rebooted  with a SNR margin of 22db! and sync 2500..
Why is my target SNR getting higher ,not to long ago it was 11db
Sad
Community Veteran
Posts: 19,100
Thanks: 437
Fixes: 21
Registered: 31-08-2007

Re: Unstable noise today!

It could be one of any number of things. The trick is to methodically (something not everyone appreciates) eliminate things, especially your own bits of kit.
You are likely to have an intermittent fault (the engineer's nightmare) it could be - your internal wiring, internal connections, your filter, your router, your line to the exchange, the BB line card.
Quote from: bigben
I couldn't hear any noise on the line ,i am  now plugged into the test socket to see if that make any difference  .
its been stable  for the last 45mins in that socket.

That's nothing I'm afraid. Intermittent line problems come and go, you could wait days before hearing anything. Such problems can disappear (sometimes for a long period) after an incoming call, the ringing current temporarily cleans the bad connection, othertimes just picking up the phone can clear it. This is one reason why you should not use any automated tests when you hear noise like that, talk straight to an adviser and get them to confirm they can hear the noise, log it, and log it as intermittent.
Quote from: bigben
Have just spoken to BT and they have done two line test.
They say as the condition is not affecting the quality of the telephone (there tests showed no fault) i should go back to my ISP. 

This is the reason why you NEVER mention Broadband when talking to your phone service provider, you get the run around. If you can't hear any noise on the line, it's pointless phoning, although at that instant, running an automated test won't harm.
The reason you plug into the test socket, the one behind the removeable front plate, is that this disconnects your internal wiring, if wired correctly, which should be connected to the back of this removeable plate. If it is not a health and safety issue, ie equipment and wires trailing across a hallway, you should stay plugged into the test socket until the fault is pinpointed.
In view of your last post you should reboot your router in the daytime mid-dayish, if you've got some good routerstats results there may be a pattern as to when your SNRM tends to be highest, the best time to reboot.
Caution - do not disconnect/reboot more than 5 times in any hour, if you do the exchange DLM thinks you have a problem. If you need to disconnect you modem/router, switch it off first, wait about a minute then unplug it all. Ideally wait a minimum of about 15 minutes before reconnecting, but if it's only a once off in say a day, don't worry.
You can determine your target SNRM by looking at the stats immediately after a reboot. The SNRM thereafter varies according to the noise on/picked up on your line.
Can you post a complete set of DSL stats, that's Downstream & Upstream sync, attenuation and Noise Margin immediately after reboot.
From your last partial figures it would appear as though your current target is 15dB. The DLM targets are in steps of 3dB from 6dB to 15dB.
Whilst conducting testing/monitoring you should use a corded phone only. Unplug and switch off any cordless phones/faxes etc. Whilst the problem is exhibiting itself, you should try a substitute filter to eliminate that as a possibility, noting previous cautions about disconnecting. You should leave the substitue in place for long enough to be sure either way. Similar procedure in due course for the router.
HTH.
bigben
Grafter
Posts: 55
Thanks: 1
Registered: 04-01-2009

Re: Unstable noise today!

SNR and Attn haven't changed since rebooted over 40 hours ago.
I thought the list of errors might be useful to understanding my issue.
adsl info --stats
adsl: ADSL driver and PHY status
Status: Showtime  Channel: FAST, Upstream rate = 448 Kbps, Downstream rate = 4032 Kbps
Link Power State: L0
Mode:                  G.DMT
Channel:                Fast
Trellis:                ON
Line Status:            No Defect
Training Status:        Showtime
                Down            Up
SNR (dB):      15.2            24.0
Attn(dB):      45.0            25.0
Pwr(dBm):      19.7            11.9
Max(Kbps):      4064            1100
Rate (Kbps):    4032            448
                        G.dmt framing
K:              127(0)          15
R:              0              0
S:              1              1
D:              1              1
                        ADSL2 framing
MSGc:          1              1
B:              127            15
M:              1              1
T:              1              1
R:              0              0
S:              1.0000          1.0000
L:              1024            128
D:              1              1
                        Counters
SF:            8766691        8766689
SFErr:          3015            10
RS:            0              0
RSCorr:        0              0
RSUnCorr:      0              0
HEC:            2119            6
OCD:            3              0
LCD:            0              0
Total Cells:    1417221459              0
Data Cells:    8091480        0
Drop Cells:    0
Bit Errors:    0              0
ES:            1603            0
SES:            21              0
UAS:            18              0
Total time = 1 days 17 hours 24 min 23 sec
SF  = 8766691
CRC = 3015
LOS = 0
LOF = 0
ES  = 1603
Latest 1 day time = 17 hours 24 min 23 sec
SF  = 3686025
CRC = 1474
LOS = 0
LOF = 0
ES  = 707
Latest 15 minutes time = 9 min 23 sec
SF  = 33099
CRC = 26
LOS = 0
LOF = 0
ES  = 23
Previous 15 minutes time = 15 min 0 sec
SF  = 52923
CRC = 28
LOS = 0
LOF = 0
ES  = 27
Previous 1 day time = 24 hours 0 sec
SF  = 5080666
CRC = 1541
LOS = 0
LOF = 0
ES  = 896
15 minutes interval [-30 min to -15 min] time = 15 min 0 sec
SF  = 52982
CRC = 26
LOS = 0
LOF = 0
ES  = 25
15 minutes interval [-45 min to -30 min] time = 15 min 0 sec
SF  = 52923
CRC = 13
LOS = 0
LOF = 0
ES  = 13
15 minutes interval [-60 min to -45 min] time = 15 min 0 sec
SF  = 52923
CRC = 18
LOS = 0
LOF = 0
ES  = 14
This lot is from the router..
Mode: G.DMT
Type: Fast
Line Coding: Trellis On
Status: No Defect

  Downstream Upstream
Rate (Kbps): 4032  448

SNR Margin (dB): 15.3  24.0
Attenuation (dB): 45.0  25.0
Output Power (dBm): 11.9  19.7

Super Frames: 8856666  8856664
Super Frame Errors: 3046  10
RS Words: 0  0
RS Correctable Errors: 0  0
RS Uncorrectable Errors: 0  N/A

HEC Errors: 2136  6
OCD Errors: 3  0
LCD Errors: 0  0
Total Cells: 1431766830  0
Data Cells: 8374101  0
Bit Errors: 0  0

Total ES: 1633  0
Total SES: 21  0
Total UAS: 18  0