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Standard User RepairExpert
(knowledge is power) Tue 03-Jan-12 16:20:23
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BT line repaired but half the download speed


[link to this post]
 
Long story but try and condense it.
Dec 11 phone went dead but one leg still connected so got nearly 2Mb download speed.
Phone fixed on 12th Dec; engineer said wire off in cabinet up road (their fault; they had been playing in there, saw them).
Phone and ADSL restored, came back at about 2Mb but ramped up to 4Mb in a couple of days. Couple of weeks later, still stuck on IP profile of 4Mb.
Phoned Virgin Media to see if they could poke DSLAM into action and get back to 6.5MB IP Profile. No joy, said your line capable of between 3.5 and 7.5 and can't report as fault to BT as I'm getting 4Mb.
Tried rebooting router and made things worse; then got (a week ago) 3Mb IP Profile. Appears stuck on that now.Phoned VM again and got nowhere; said contact BT for test.
Phoned BT and got a line test; 99% on voice and they won't even discuss ADSL noise etc.as I'm with VM as an ISP.
Just gone round in circles as nobody wishes to help. Is it a coincidence that my speed halved after line was repaired? I think not!
Have just got 3com router stats from router page; just how bad are they and what speed would you expect? I'm not very good at interpreting them.
I'm only 1 mile from exchange and have been getting 6MB off peak for more than 5 years.
Found a copy of old stats from 2007 for comparison...
Receive att=23dB, Receive margin 10dB, RX output power 0dBm, Send att 11dB, Send margin 26dB.

New readings from 3com below. Can someone interpret them please.

http://i42.tinypic.com/wi8t8x.jpg

Thanks in advance,
Mike.

______________________________________________________________________________
Mike (Retired Radio & Electronics Engineer)
VirginMedia ADSLmax, up to 8Mb.

Edited by RepairExpert (Tue 03-Jan-12 16:21:13)

Standard User huwwatkins
(member) Tue 03-Jan-12 16:49:23
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Re: BT line repaired but half the download speed


[re: RepairExpert] [link to this post]
 
You are only syncing at 4000kbps - this is why your IP profile has dropped. More like a line fault than an IP profile issue.

Edited by huwwatkins (Tue 03-Jan-12 16:51:24)

Standard User RepairExpert
(knowledge is power) Tue 03-Jan-12 17:11:06
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Re: BT line repaired but half the download speed


[re: huwwatkins] [link to this post]
 
Thanks Huw; that's what I thought but BT don't want to know; as long as the phone works that's all they worry about. As long as I'm with an ISP other than them they don't want to know.
Mike.

______________________________________________________________________________
Mike (Retired Radio & Electronics Engineer)
VirginMedia ADSLmax, up to 8Mb.


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Standard User XRaySpeX
(eat-sleep-adslguide) Tue 03-Jan-12 17:40:14
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Re: BT line repaired but half the download speed


[re: RepairExpert] [link to this post]
 
In reply to a post by RepairExpert:
BT don't want to know
No reason for them to do so; they don't supply your BB. It's VM's responsibility.

1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 19 Meg WBC
Administrator MrSaffron
(staff) Tue 03-Jan-12 18:15:46
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Re: BT line repaired but half the download speed


[re: XRaySpeX] [link to this post]
 
Agreed, it is down to VM to liase with the right part of BT to deal with the fault.

40dB attenuation, a big increase it seems, but not uncommon after a repair, as they may use a different pair, i.e. its longer.

4000 is it always that value? i.e. if you restart modem?
4000 at 40dB attenuation is about half what should be possible, so does indicate an issue somewhere. Alas most ISP staff and BT staff have little idea of the correlation between dB attenuation and sync speeds.

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 RepairExpert
(knowledge is power) Tue 03-Jan-12 19:15:28
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Re: BT line repaired but half the download speed


[re: MrSaffron] [link to this post]
 
Thanks Andrew; rebooting the router always comes back with the same figures.
I think you may be right about them using another pair; quicker than finding the wire that someone pulled off. Pity they just didn't reconnect that one; all would have been well again. Guess I had a better pair for all those years.

I agree that it's not BT's concern as long as I get a usable phone line, and I doubt they'd bother to find a better one for me even if I changed my ISP over to them.

Guess I'll have to live with it until I loose the line again and have the chance to get yet another pair.

Mike.

______________________________________________________________________________
Mike (Retired Radio & Electronics Engineer)
VirginMedia ADSLmax, up to 8Mb.
Standard User b4dger
(knowledge is power) Wed 04-Jan-12 12:00:01
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Re: BT line repaired but half the download speed


[re: RepairExpert] [link to this post]
 
As MrSaffron was suggesting/asking - Strange if it always connects at exactly 4000Kbps.

Are VM able to cap/band someone's sync?

Edited by b4dger (Wed 04-Jan-12 12:01:00)

Standard User InQ
(member) Wed 04-Jan-12 13:24:13
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Re: BT line repaired but half the download speed


[re: RepairExpert] [link to this post]
 
Line attenuation increase of 23dB to a 40dB.....thats some re-route.
I'd be seriously annoyed.

Whats your location in relation to the exchange?
Sometimes (like mine) you know the route of the cables from the exchange and that they wouldnt go anywhere but straight to the cabinet down the road but there is of coruse some situations where they potentially could do a circuit somewhere out the way from your house especially if its a heavily built up area.

Dont rule out BT messing something up and you not being re-routed onto another line around god knows where.
Standard User RepairExpert
(knowledge is power) Wed 04-Jan-12 14:22:12
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Re: BT line repaired but half the download speed


[re: InQ] [link to this post]
 
Hi all,

When I said it always rebooted at 4000 I meant around that figure (at the moment it's 3936); although at one stage it got to around 4100 which allowed an IP Profile of 4000; since that time it's always been a bit lower, hence it's dropped my Profile to 3000 (can't see why it doesn't allow 3500, always used to go up in 500's didn't it?).

I'm almost exactly 1 mile from the exchange and the route is pretty straight; can't think how they managed a different route as there are no other options I can see; but how do you account for such an increase in attenuation, unless it's just a [censored] line?

I can't see them changing it however much I moan as the voice line test comes back at 99% (think they said 85-100% were the limits for a good voice line. They couldn't care less about the ADSL problem as I'm not with them as an ISP.

I have a friend who works on the lines in this area who may be able to find out what they did, but doubt he'll be able to reconnect a better line for me. Will let you know what he says if he can find out.

Mike.

______________________________________________________________________________
Mike (Retired Radio & Electronics Engineer)
VirginMedia ADSLmax, up to 8Mb.

Edited by RepairExpert (Wed 04-Jan-12 14:23:29)

Administrator MrSaffron
(staff) Wed 04-Jan-12 16:54:11
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Re: BT line repaired but half the download speed


[re: RepairExpert] [link to this post]
 
Precision is important, thankfully spotted this post.

The small variations tell us that you are probably not being banded, which on IPStream should only apply at 0.5/1 and 2, but with WBC more bands that can give a near fixed speed are available.

To be honest VM ADSL is one of the bad ones, they sell it only so they can say they have a national presence. You are likely to do better from moving to a different provider, and one where people with problems are seen to be having them fixed.

Without actual access to the line records and physical cabling it is impossible to tell if your old line could have been reused - generally BT engineers don't re-route unless there is no other option.

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.
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