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Standard User broadbandjockey
(member) Wed 11-Jun-14 08:12:12
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Drop of Sync Speed from 20 Mb/s to 288 k !!


[link to this post]
 
My mother in law moved ten months ago into a flat, next door to the local telephone exchange

Not surprisingly she had a sync speed of about 20 Mb/s.

About ten days ago the downstream speed started to slow, yesterday it had dropped to 576k. The noise margin has reciprocally increased, and was about 31dB.

Suspecting her router, I swapped it yesterday, for a spare one of mine. That kicked off at 576k
too, hoping that perhaps the the original router had been faulty, I was rather hoping the speed
would creep back up to 20 megs over the next few days, however within three hours the sync speed
dropped even further, it's now down to 288k.

Upstream has been unaffected throughout, about 1.1 to 1.2 Megs at 6dB margin.

What on earth is going on ? I've raised a ticket with PlusNet, no response yet.
Administrator MrSaffron
(staff) Wed 11-Jun-14 10:24:43
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Re: Drop of Sync Speed from 20 Mb/s to 288 k !!


[re: broadbandjockey] [link to this post]
 
If downstream noise margin is high and the sync speed still slow just after router has been rebooted, then suggests that the BT Wholesale DLM system has forced banding onto the connection in a very drastic manner in your case.

Does the router, show error stats too?

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 11-Jun-14 10:38:53
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Re: Drop of Sync Speed from 20 Mb/s to 288 k !!


[re: broadbandjockey] [link to this post]
 
When you say "Next door ..." how close do you mean?

Can you get full stats including attenuation and errors. And an estimate of line length.

I dealt with one like this a few years back - basic ADSL or ADSLmax and it was the ultra short line causing problems.


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M H C


taurus excreta cerebrum vincit


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Standard User broadbandjockey
(member) Wed 11-Jun-14 11:04:56
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Re: Drop of Sync Speed from 20 Mb/s to 288 k !!


[re: MHC] [link to this post]
 
In reply to a post by MHC:
When you say "Next door ..." how close do you mean?

Can you get full stats including attenuation and errors. And an estimate of line length.

I dealt with one like this a few years back - basic ADSL or ADSLmax and it was the ultra short line causing problems.


Distance as the crow flies about 200 metres

Router Stats:-


DSL Status: UP
DSL Modulation Mode: Auto
DSL Path Mode: INTERLEAVED
Downstream Rate: 284 Kbps
Upstream Rate: 1100 Kbps
Downstream Margin: 31 db
Upstream Margin: 6 db
Downstream Line Attenuation: 17
Upstream Line Attenuation: 15
Downstream Transmit Power: 15
Upstream Transmit Power: 11
LOS Errors: 0

PVC Connection

PVC Status: UP
Encapsulation: RFC 2364 PPPoA
Multiplexing: VC
Autodetect: Disable
VPI: 0
VCI: 38
Standard User RobertoS
(sensei) Wed 11-Jun-14 11:08:40
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Re: Drop of Sync Speed from 20 Mb/s to 288 k !!


[re: broadbandjockey] [link to this post]
 
Does her phone work?

My broadband basic info/help site - www.robertos.me.uk | Domains,site and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 58.7/14.6Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
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Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
Standard User broadbandjockey
(member) Wed 11-Jun-14 11:11:33
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Re: Drop of Sync Speed from 20 Mb/s to 288 k !!


[re: RobertoS] [link to this post]
 
In reply to a post by RobertoS:
Does her phone work?


Yep, clear audio and no audible noise on the line

If it was a noisy line problem, I'd expect a noise margin of 6dB (or lower) ?

Edited by broadbandjockey (Wed 11-Jun-14 11:17:13)

Standard User MHC
(sensei) Wed 11-Jun-14 11:26:24
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Re: Drop of Sync Speed from 20 Mb/s to 288 k !!


[re: broadbandjockey] [link to this post]
 
That rules out my thoughts - the one I dealt with had a line length of under 20 metres. At over 200m it would not be relevant.


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

M H C


taurus excreta cerebrum vincit
Standard User RobertoS
(sensei) Wed 11-Jun-14 11:51:52
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Re: Drop of Sync Speed from 20 Mb/s to 288 k !!


[re: broadbandjockey] [link to this post]
 
I was thinking of one wire off.

My broadband basic info/help site - www.robertos.me.uk | Domains,site and mail hosting - Tsohost.
Connection - Plusnet UnLim Fibre (FTTC). Sync ~ 58.7/14.6Mbps @ 600m. - BQM

"Where talent is a dwarf, self-esteem is a giant." - Jean-Antoine Petit-Senn.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Allergy information: This post was manufactured in an environment where nuts are present. It may include traces of understatement, litotes and humour.
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