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Standard User badnoisemargin
(newbie) Tue 16-Apr-13 20:13:22
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Advice on extremely low noise margin


[link to this post]
 
Router is plugged directly into master socket, there are no phones or other equipment on the line.

Line attenuation is 12db down 0.5db up

Noise margin up is 7db, but noise margin down hovers around 6db-4db and dips to -2db.

The router is losing sync every 2-3 minutes. Restarting usually re-establishes sync but it usually loses it again within 10 minutes or so. There have been sync problems on the line for around the last 5 days, and they've steadily been getting worse.

What steps do I take in fixing this? ADSL and phone service are through TalkTalk, do I call them? Or do I call BT because it looks like a line problem?

There have been high winds in my area over the last few days. The line looks clear up to the nearest telegraph pole, but lots of other lines in the area hit tree branches etc. and I noticed there are a couple of lose lines swinging from the pole.

Really need to get this sorted ASAP, any help appreciated. Thanks.
Administrator MrSaffron
(staff) Tue 16-Apr-13 21:01:53
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Re: Advice on extremely low noise margin


[re: badnoisemargin] [link to this post]
 
You call TalkTalk who handle all customer interaction and they fault find and arrange an Openreach engineer to look at the line if they feel there is a fault.

The 12dB down and 0.5dB attenuation up look odd too.

Andrew Ferguson, andrew@thinkbroadband.com
www.thinkbroadband.com - formerly known as ADSLguide.org.uk
The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User MHC
(sensei) Tue 16-Apr-13 21:34:30
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Re: Advice on extremely low noise margin


[re: badnoisemargin] [link to this post]
 
Avery strange set of figures ...

0.5 dB - even next to the exchange would normally get 2dB or more. Then with the noise margins - I would expect to see the UP figure being way more than 7dB and similarly with the down figures unless you are in a really "electronically" noisy area.

Can you check them again ...

Do you know how far you are from the exchange - straight line and by road?


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

M H C


taurus excreta cerebrum vincit


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Standard User badnoisemargin
(newbie) Wed 17-Apr-13 11:52:52
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Re: Advice on extremely low noise margin


[re: MHC] [link to this post]
 
Thank you both for your replies.

Here are the stats this morning.

http://i.imgur.com/jBsRtB3.png


Connection seems to be a bit more stable this morning, sync is holding with 6db noise margin.

Is it possible the problem is my router/modem? I've been using it for four or five years. Its awlays worked fine but these stats do look odd to me too.
Standard User MHC
(sensei) Wed 17-Apr-13 12:13:03
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Re: Advice on extremely low noise margin


[re: badnoisemargin] [link to this post]
 
Still a little odd.

Can you confirm how far from the exchange you are - a good approximation.


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M H C


taurus excreta cerebrum vincit
Standard User badnoisemargin
(newbie) Wed 17-Apr-13 12:33:06
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Re: Advice on extremely low noise margin


[re: MHC] [link to this post]
 
Very close - well under 1 mile.

Edit: google maps says 0.3 miles

Edited by badnoisemargin (Wed 17-Apr-13 12:35:28)

Standard User MHC
(sensei) Wed 17-Apr-13 12:43:10
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Re: Advice on extremely low noise margin


[re: badnoisemargin] [link to this post]
 
So 0.3 mile - that immediately tells me that the Upstream attenuation is wrong.

Is that straight line or an approximation of "by road"?

Maybe you need to record all your settings and do a full reset. Leave everything disconnected for 30 minutes if you do, three minutes is normally enough but I prefer a longer period so the DSLAM will start afresh when you restart.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

M H C


taurus excreta cerebrum vincit
Standard User badnoisemargin
(newbie) Wed 17-Apr-13 13:05:58
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Re: Advice on extremely low noise margin


[re: MHC] [link to this post]
 
0.3 miles is by road.

By a "full reset", do you mean a software reset of the router, restoring back to factory settings?

Or just turning it off and leaving it off for 30 minutes?

Thanks!
Administrator MrSaffron
(staff) Wed 17-Apr-13 13:19:27
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Re: Advice on extremely low noise margin


[re: badnoisemargin] [link to this post]
 
For full ADSL stats, switching off and a short wait to make sure exchange end has forgotten all about the connection.

Andrew Ferguson, andrew@thinkbroadband.com
www.thinkbroadband.com - formerly known as ADSLguide.org.uk
The author of the above post is a thinkbroadband staff member. It may not constitute an official statement on behalf of thinkbroadband.
Standard User MHC
(sensei) Wed 17-Apr-13 13:20:44
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Re: Advice on extremely low noise margin


[re: badnoisemargin] [link to this post]
 
A full factory reset and leave everything off.


I would expect to see the Upstream attenuation somewhere between 4dB and 8dB for that distance.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

M H C


taurus excreta cerebrum vincit
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