>>> after all still there is hight SNM
Yes... but No
Your
SNRM although related is not quite the same thing as
'real' SNR. The SNRM includes a margin for errors, but your 'real' SNR must be low.
This is obvious from the DMT bit loading graph which is showing only a few bits loaded across the whole range. If you say look at at tone 60 which is around 258kHz, you can see there is only 5 bits loaded into that frequency bin. Normally on a good line Id expect to see 14-15 bits loaded in that tone. This is telling me that theres something wrong with your real SNR and infers that you are getting a lot of noise and/or interference from somewhere. Its also a bit too spikey
Your SNRM can be kept artificially high by the
target SNR, which is why on first glance your SNR Margin looks ok.
However the DMT graph - in particular the bit loading - tells a totally different story.
When you look at the whole picture its pretty obvious that you are suffering badly from noise.
Unfortunately I dont have a DMT graph of a 27dB atten line to show you for comparision, but during the early stages those blue lines should be 2 or 3 times higher than they are... and it should be smooth. The SNR Monitor is juttering all over the place which is another indicator of noise.
If you have checked all your internal wiring and equipment then you should contact your ISP to arrange an engineers visit to look at that line.
That line is behaving more like one that is about 4km from the dslam, rather than 1.5 km from the cab.
Is the voice side of your telephone ok - When using the telephone does it seem crackly or noisy?
Poll
