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Standard User mikegg
(newbie) Sat 30-Mar-13 11:37:01
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Line Length Issue

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Long history that I won't go in to but had lots of speed problems since FTTC installation in November. Estimated was 32 and I got 37 on the first day - progressively drops to around 16 -18. Six engineer visits and still the same. After the last visit its now only ever at max 18.

BT now saying that I have 'excessive' line length, specifically that tests show that its between 350 and 600 m from the DP (note NOT the PCP) to my Socket when I know that the pole is outside my house and its a total of 32m !!! Their estimates of the exchange to PCP length and the PCP to the DP length (600m) are about right.

I can't seem to get them to understand - any thoughts on a theory of whats going on ?

Standard User yarwell
(sensei) Sat 30-Mar-13 11:53:15
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Re: Line Length Issue

[re: mikegg] [link to this post]
I don't see how they can remotely determine the DP to NTE distance.

If it's dropped from over 30 to under 20 it's a fault and their's to fix.



MaxDSL - goes as fast as it can and doesn't read the line checker first.

MaxDSL diagnostics
Standard User panda
(committed) Sat 30-Mar-13 11:59:12
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Re: Line Length Issue

[re: mikegg] [link to this post]
It is not always the case that the DP is the last pole before the property.
although more common in rural locations, but it is quite possible for the DP to be some distance away, with the lines extended to the pole outside your house - usually by either an aerial cable (which carries multiple lines) or a drop wire.

Eats shoots and leaves.

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Standard User Bald_Eagle1
(experienced) Sat 30-Mar-13 12:10:50
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Re: Line Length Issue

[re: mikegg] [link to this post]
DP = Distribution Point.

Not all poles have the actual distribution point which could actually be located a few poles away from the one you mention, or even possibly somewhere underground (e.g. in a chamber).

Having seen BT's Network Records for my connection & physically measuring the known route with a trundle wheel, I do know for certain that my connection is a little over 1000m to the DP from the FTTC cabinet plus around 40m from the DP to my master socket.

I do suspect that your connection is actually quite a bit more than 600m in total length from the cabinet, perhaps around 900m or so (or it does have a 'fault').

When DLM has been reset (following a number of engineer visits until physical line problems were eventually permanently fixed), my connection can sync at up to 35Mb, reducing to 27Mb or so after DLM eventually applies Interleaving etc.

Your 18Mb does seem quite low from the initial 37Mb, but you may be be suffering from poor condition cabling/joints etc.

If you are using a Huawei HG612 modem & are a Windows user, you could 'unlock' the modem to allow access to its stats & use the HG612 Modem Stats 1.0 suite of programs (available for free download here:- HG612 Modem Stats 1.0) to monitor your connection stats as both snapshot current conditions and/or monitor ongoing stats 24/7.

That may highlight where the problem lies.

HG612 modems, both locked & already unlocked regularly appear on ebay, so if you wished to keep your existing HG612 in 'as installed' condition, you could use the spare one just for dtats gathering purposes.

If you were provided with an ECI modem (not impossible, but quite difficult to unlock & its stats are currently rather unreliable), an unlocked HG612 will still work on your connection.

Are your speeds checked wirelessly?
For a true reflection of your connection's performance, you would need to connect to the router/hub via ethernet cable.

Also, which Operating System are you using on the PC you use for speed testing?

It may help if you posted the results from the BT speed test at (including the Further Diagnostics data that will also report your current IP Profile).

Edited by Bald_Eagle1 (Sat 30-Mar-13 12:14:10)

Standard User mikegg
(newbie) Sat 30-Mar-13 18:54:22
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Re: Line Length Issue

[re: Bald_Eagle1] [link to this post]

Speeds check via ethernet cable direct to Router, using Win XP

Extract from BT email - DP 411 is the pole outside my property, 32m from the socket.

Line loss calculator shows:-
exchange to PCP 9 1882 metres
PCP 9 to dp411 596 metres
line test 2.85km
Suggests DP to EU 372 meters of unpredicted line length.

Another test system shows Estimated length 1212m PCP to EU also confirming the line is longer than estimated.
Possibly 616 metres DP to EU.
Standard User asbokid
(member) Sat 30-Mar-13 21:24:49
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Re: Line Length Issue

[re: mikegg] [link to this post]
Happy Easter, MikEgg!

A "line loss calculator" sounds like it's using attenuation measurements to estimate loop length.
Maybe beg, borrow or steal a Time Domain Reflectometer, and measure the lengths yourself. The measurements using TDR will be within a few per cent, and even better for shorter lengths. With the meter configured with the correct cable parameters (and a competent operator!) it should be able to measure the distance from NTE to DP to a precision of a few centimetres.
Can you see the DP at the top of that pole? Does the line follow the obvious path from thereon to your home?
Such a dramatic drop in your data rates suggests a line fault has developed. If so, hopefully it will get rapidly worse to the point of total failure!
cheers, a
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