SNR differences between my std ADSL and MAXDSL

Morning all,

Looking for some understanding of SNR differences.

I have two Zen Office ADSL products at my office.

1 Office (20-1) 512K with a DrayTek 2600VG reporting SNR of 33.5 Loop Attn of 44.5

1 Office Max 8MB ADSL with DrayTek 2800VG reporting SNR 6.5-7.0 Loop Attn of 44.5

Now both lines should be about the same distance fro the Exchange, so how comes the SNR is so low on the MaxDSL is this normal on a MaxDSL.

The router shows a sync of 832K Up and 6.9M Down.

They are both running on filtered master faceplates from Solwise and there is nothing else connected to the Max Line.

I get ocasional ping losses on my VPN tunnels into the Max as well as lost pings to it's external address from my home ADSL.

Do I have a line issue ? or is Max just still too leading edge ?

Paul

the available margin decreases as the sync rate goes up. Max will try to attain the highest sync rates until either it gets to the max rate or it all goes pair shaped.

So as I understand it, that means that it will ramp up the sync rate until the SNR gets too low for a reliable link ?

It actually did it the other way round for me, started with a high sync speed, then dropped it (and, eventually, increased margin) until I had a stable line.

it starts with a target 6 dB SNR margin. If that is too wobbly it should step it up, reducing speed as it does so.

What it actually does of course is sync at the speed which gives a 6dB noise margin (initially). If this proves to be very unstable then the target noise margin will be increased in 3dB steps up to a maximum of 15dB (I think), which will result in progressively lower sync speeds. Interleaving might be switched on if the errors are of the kind which can be improved by interleaving.

Eric

Thanks all, that makes the differenes in my SNR levels clear.

Have a good Weekend all.

Paul