In reply to a post by Bald_Eagle1:

When FTTC was installed last June (8c profile, but prior to access to unlocking firmware), sync speed must have been around 35Mb or so as I was actually downloading at up to 33Mb for almost a full month before everything started to go pear-shaped.

Shame - that suggests you should be getting well over 40 on 17a, or at least bang-on 40 on capped.

DLM was reset during a fairly recent engineer's visit (9th March). Sync speed was 35322 k for a short while before starting the usual downward journey.

That's odd - going from 8c to 17a should have made a significant difference.

I thought SRA was in place, hence "on the fly" resyncs that are so quick (16 seconds or so) that they do NOT initiate a new PPP session & therefore do NOT update the BT IP Profile/BRAS Rate.

Well, that depends what router you use - I've set mine to a custom PPP timeout of 60 seconds so I can manage a full modem reboot and still not initiate a new PPP session (primarily to keep my IP address for the TBB monitor).

A 16-second resync isn't SRA - with SRA in place, it doesn't go down to resync at all. It just seamlessly reduces your rate from one second to the next, hence the name. Course, that would totally break BTw's IP profiling system which is only why the rare LLU provider on ADSL2+ has tried it.

Yep, I have looked into that.
However, as spare pairs are available in the existing D-Side bundle, they would simply use those.
I have already had the D-Side pairs swapped in an effort to eliminate a single faulty pair.
My belief is that dodgy joints/connections are the root cause of my issues, perhaps only being noticed as my connection speed NEVER reaches the maximum for the capped 40Mb service, therfore my connection is already in a "delicate" condition.

It appears I may be the very last house on my STD code & have the option of a new line from a different exchange.
However, the closest fibre cab from that exchange is over 2km from my home!!!!!!

Shame then. As mentioned I'd expect if you were getting 35mbps on profile 8c then you should be hitting the 40mbps cap all the time on 17a. Have you got a full modem stats pic somewhere I can see?

Only other thing I can think of, if BT can't/won't fix your line - get a second line installed to someone else's home, whom you know has a good line, and pipe it over to yours via Ethernet?

I used to get 32-35mbs upload and about 6-7mbs download. Since upgrade I get a a variable 55- 65mbs upload never less than 50mbs (so far) and a almost constant 10mbs up load.

Edited by elevator (Mon 07-May-12 16:07:15)

In reply to a post by qasdfdsaq:

Shame then. As mentioned I'd expect if you were getting 35mbps on profile 8c then you should be hitting the 40mbps cap all the time on 17a. Have you got a full modem stats pic somewhere I can see?

I thought that too (at first). Almost everyone else saw increases in DS speeds when 17a was introduced.

However, I think that attenuation is simply too high on my connection (due to distance and/or condition of the cables/joints) to achieve the full fat 40 Mb.


8c profile:-

Discovery Phase (Initial) Band Plan
US: (0,95) (696,1183)
DS: (32,687) (1192,1627)
Medley Phase (Final) Band Plan
US: (0,95) (696,1183)
DS: (32,687) (1192,1627)

17a profile:-
Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)

My bit-loading cuts off at around tone 1750, usually lower, so the increase in DS tones from 1627 (8c) to 1963 (17a) is pretty much wasted for my connection.


Which full modem stats pic do you mean?
I have some graphs from my 8c connection & thousands from my 17a connection, if that's what you meant.

In reply to a post by Bald_Eagle1:

Which full modem stats pic do you mean?
I have some graphs from my 8c connection & thousands from my 17a connection, if that's what you meant.

One of the "combo" ones like the one I posted. I'd like to see noise and attenuation across the spectrum.

Here's one from this morning, just after the connection resynced "on the fly"

Current_Stats

How long is your line? Or rather what's your distance to cabinet if you know? And what does BT estimate your speed should be?

Engineers have reported it as various lengths, between 820m & 1100m.

I physically measured what I believe to be the route at just less than 1000m (using a trundle wheel).
It could be possibly between 900m & 950m depending on exactly where/how it crosses the main road & up the road to the cabinet itself.

When FTTC was installed, my estimate was 14.6Mb & I achieved 35Mb sync speed.

Shortly after 17a was introduced my estimate went up to 24Mb.

Currently my estimate is 30Mb.

FWIW, here's a graph of my IP Profiles (not sync speeds):-

IP Profiles

Some of the data from the first month is a bit vague.
My connection was that good back then that I didn't need to monitor it every day.

All the really low profiles are from the intermittent issues that have needed engineer visits.
Faults were found & supposedly fixed at every visit!!!

Edited by Bald_Eagle1 (Mon 07-May-12 16:53:19)

In reply to a post by qasdfdsaq:

I also used a shorter modem lead and wired it straight into the socket (the filtered IDCs behind the bottom plate) which also cut off about 0.3-0.5dB.

?????
Pardon?

Do you mean the un-filtered?

In reply to a post by RobertoS:

In reply to a post by qasdfdsaq:

I also used a shorter modem lead and wired it straight into the socket (the filtered IDCs behind the bottom plate) which also cut off about 0.3-0.5dB.

?????
Pardon?

Do you mean the un-filtered?

Nope, I meant the filtered ones.

You have me thinking I've thrown a complete wobbly!

There should be no VDSL2 signal on filtered terminals. The filter is supposed to removed anything outside audible frequencies from the output, as otherwise you wouldn't be able to use the phone because of the racket. xDSL connections are unfiltered.

I don't think I've gone mad. So either I have, or you are not correct in what you say you have done, or you need to see what happens if you connect the modem with a standard ADSL cable into the DSL socket on the front of the faceplate.

Edited by RobertoS (Mon 07-May-12 17:48:16)