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Borderline attenuation level


Borderline attenuation level

Hi all,

I wonder if you could give me some advice. I was connected to Premier 2Mbps last week as a new customer, but have been put on a 1Mbps connection. I didn't receive any emails from PN warning me that this was the maximum achievable; indeed I still have the emails saying my line has passed the BT tests. According to samknows I am only 1.01km away from CMSUT exchange as the crow flies.

PN have done a whoosh test today, and the results were:

Upstream xDSL Link Info
Loop Loss 25.5 dB
Cell Count 160
Downstream xDSL Link Info
Loop Loss 43.5 dB
Cell Count 173

Obviously 43.5 dB is on the 43-45ish borderline for attenuation, and according to my router (a new Linksys WAG354G) the connection details are:

Downstream Rate: 1152 Kbps
Upstream Rate: 288 Kbps
Downstream Margin: 27 db
Upstream Margin: 28 db
Downstream Line Attenuation: 43
Upstream Line Attenuation: 25

This therefore agrees over the line attenuation level, but PN's test doesn't seem to have tested the SNR margin, and I'd have thought at 27 dB I should be OK for 2Mbps.

The SNR ratio does seem to fluctuate a bit, but the lowest I've seen is 19 dB, highest 30 dB, and usually around 27 dB for most of the time.

So, the question is, do I ask PN to regrade to 2Mbps? I'm tempted to go for it, as from other posts people seem to have had acceptable quality with higher attenuation and lower SNR margin. Do people think I should be OK, or is loss of sync likely to be a significant risk? If so, how long does it usually take to regain sync? Oh, and what does the Cell Count mean? Is higher or lower a Good Thing? Smiley


Borderline attenuation level

Just to let you know - I have an attentuation level of 41, signal to noise 30db (confirmed on whoosh test too) but BT seem very reluctant to upgrade my 1mb connection to 2mb (twice now I might add).

I think its because bt's database shows that 1mb is max for my area. Sad

So even if you think/are within limits, theres still sometimes a fight on to get that elusive 2mb link. Sad
Posts: 2,886
Registered: 30-07-2007

Borderline attenuation level

Bt are sticking tightly to their limits at present, as the rash of upgrades to 2Mb has given them a lot of connection problems to sort out.
So if their records show you can only get 1Mb, then 1Mb it is.

On some occasions where BT's database is obviously wrong, people have contacted Mr Saffron at ADSL Guide and he has got BT to change it. Why him and how he does it I don't know.

But if your figures are borderline over 43dB attenuation, then I'd expect BT to turn you down.