In reply to a post by WWWombat:

If a line is working OK, then the most significant impact is crosstalk from other subscribers. As take-up increases, crosstalk only tends to increase, so speeds only tend to go down.

Yes, I seem to have a good line. My max attainable when I first changed to Infinity 2 was around 101/34, it has now fallen to around 90/34. Unfortunately I do not know how full my cab is so it may fall further. (though I hope not).

Better than the predicted and sync around 21000

WBC FTTC Up to 14.3 Up to 1 -- Available
WBC ADSL 2+ Up to 1 -- 1 to 3.5 Available
ADSL Max Up to 1 -- 0.75 to 2.5 Available
WBC Fixed Rate 0.5 -- -- Available
Fixed Rate 0.5 -- -- Available
Other Offerings
Fibre Multicast -- -- -- Available
BET Up to 2 -- -- Available


http://www.thinkbroadband.com/speedtest/button/13686...

Estimate: 26.3DS 5.6US

First Sync 36DS 6US

Now 25.8DS 5.2US

BT estimate is 66 down 20 up.

Was getting 80/20 until local power problems with HT cables saw big drop in speed and erratic changes of interleave due to frequent power outages.

Put modem/router onto battery backed UPS and hey presto back to 80/20 and back on fastpath with <10,000 FEC errors a day.

the moral of the tale is that a dirty power supply can affect electrical equipment big time as well as line quality.

more likely to go down than up I am afraid, you might get lucky and openreach fix a fault somewhere which helps you, but more likely will go down with crosstalk.

I actually started on full sync but now get significantly lower.

My neighbour who managed to get a better pair now has crosstalk again, so his fix didnt last that long.

In reply to a post by Chrysalis:

My neighbour who managed to get a better pair now has crosstalk again, so his fix didnt last that long.

That's interesting.

Do you or your neighbour have any stats/graphs that demonstrate the changes between no crosstalk & then with crosstalk?

The QLN/SNR graphs are possibly the most likely to show something changing.

yes and I have posted mine before, but I cant do that animation thing you did.

Basically the difference is the QLN goes up, on my line it went up on D1 a lot, D2 a little and barely at all on D3 but of course D3 is the weakest part of the frequency. SNR went down a lot, most of the loss of SNR on D1, a bit on D2 and D3 not affected much. My SNR on D1 isnt much higher than D2 now, D1 has taken a battering.

Hlog stays the same as well as attenuation.

ok here is some I made, the SNR has 3 stages as it seems I have had further loss since the first time I got hit with crosstalk. So actually D2 was also badly affected although not so apparent on the snr.

qln crosstalk
snr crosstalk

Edited by Chrysalis (Fri 17-May-13 10:04:46)

Quite dramatic changes shown there (a bit too quick to view clearly for my eyes though)

Do you have any idea if that was caused by just one new user or by a batch of new users?

unfreez is brilliant for creating animated gifs. Small, stand alone, free. Also has a delay setting.

I was bored so here you go BE:

QLN-CT.gif
SNR-CT.gif