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[g3uiss]

Suddenly over last 36hrs been getting jittery SNRM DS (US was always a bit) I know its always a bit bumpy, but this is quite pronounced. Other stats seem normal and quite line test fine.

Thoughts appreciated.

Plot attached, or view as g3uiss on MYDWS

Tony

[NewtronStar]

Looks a bit like Kitz's SNRM with oscillations on both DS & US and your both on ECI cabinets dont think we have found out why this is happening as of yet anything from a dodgy line card to external noise 

[g3uiss]

Thanks that's useful. Hadn't noticed Kitzs stats, although had tried to find one similar.

Looks like wait and see

Tony

[PhilipD]

Hi

See my last few posts on this subject here
http://forum.kitz.co.uk/index.php/topic,18830.75.html

In my case they had put a generator for traffic lights near the cabinet, this was causing electrical noise, when they went the noise went. 

VDSL is quite sensitive, so anything could be going on anywhere near the cabinet or bundle of telephone lines introducing noise, in my case I was lucky and found out what was causing it and it was only temporary. 

Have you checked roadworks.org to see if anything is going on locally?

Regards

Phil

[g3uiss]

Hi Phil

I walk past the Cab every day, and nothing obvious. However on thinking about it more, there is a building development across the Rd about 100yds from the Cab. Its been on going for some months, but its nearing completion, they may have a generator or other equipment running. Its interesting it started on the 27th about 1757, and had a break from 0540-1200 the next day and has been consistent ever since.

Surprised my CRC/ES hasn't changed much really, would have expected and error rate increase with electrical noise. The line card is a strong contender I think

Tony

[PhilipD]

Hi

Don't forget that the SNR we look at is a margin over and above what is required for that sync speed, it is there for just these sort of reasons, so whilst it is up and down at the minute, it's only decreasing the margin so still allows the line to work more or less just as well in this case.

Regards

Phil

[g3uiss]

Phil

Thanks for the comment. Yes and on a way, it's the change that puzzles me. It's never been a flat line very few are as there are so many external effects on the noise margin.

It was about the sudden change that made me curious. As you say little change in the overall line performance.

Tony