Could someone have a look at my line stats please?

[dav333]

Here are the other graphs.

Graph 1 is the noise margin of the router plugged into the the test socket this morning (sync 8128)
Graph 2 is the bits and tone graph of the router that i took a short while before disconnecting from the test socket (not sure if should have left this running for more time...)

Graph 3 is the noise margin of the router plugged into the the regular computer room socket straight afterwards (sync 6944)
Graph 4 is the bits and tone graph of the router plugged into the the regular computer room socket straight afterwards


Could someone analyze these graphs please?

(I made another post with more graphs and questions at the bottom of the previous page just in case anyone misses it )

[waltergmw]

Hi Dav,

The Netgear DG834 v3 uses the Texas Instruments AR 7 Chipset which is known to have a bug in it so it would be a very good idea to upgrade the firmware if necessary.

Kind regards,
Walter

[jeffbb]

Hi

The second set of graphs show that there is a lot more noise . This almost certainly due to some problem with your internal wiring
The SNR margin graph is very noisy. You can also see the effect on the bit loading from about tone 160 to 254 .

Have followed the  2 Links  contained  Roseways posts ?? regarding sockets and trouble shooting.

http://forum.kitz.co.uk/index.php/topic,6763.msg144989.html#msg144989
http://forum.kitz.co.uk/index.php/topic,6763.msg146342.html#msg146342

Regards Jeff

[dav333]

Thanks for all the help you have provided in this thread.
I have followed some of the advice in this thread and website and have now a) updated the routers firmware and b) installed a filtered adslnation faceplate. The router is now directly plugged into the faceplate without needing the telephone extensions and filters it previously had. All the cables are new.
The result is that I am now always syncing at 8128 with an increased IP profile of 7150. I seem to have a slightly higher ping when running various ping tests although i am guessing this is coincidental?  The noise margin is slightly more stable and higher (average about 6db) although I am still experiencing a lot of fluctuation with some big drops or rises (e.g from 9db to 2db) although without a loss of sync.

I assume the noise margin fluctuations are therefore due to either a) as yet unknown sources of interference outside my house b) as yet unknown sources of interference inside my house or c) the router (less likely?)

Also, in an effort to tidy up some of my cables trailing around the room I tied a power cable to the routers ethernet cable at various points along its length. However when i checked routerstats my noise margin was fluctuating all over the place.  As soon as I untied them and moved them away from each other the fluctuations were reduced. Can something as simple as cables touching or crossing each other cause big fluctuations in noise margin?

[jeffbb]

Hi
quote : Can something as simple as cables touching or crossing each other cause big fluctuations in noise margin?

The short answer is yes .Normally  not wise to have data cables running close to mains cables .

Glad to see that your connection seems to be much better now 

quote I assume the noise margin fluctuations are therefore due to either a) as yet unknown sources of interference outside my house b) as yet unknown sources of interference inside my house or c) the router (less likely?)

yes you have covered most scenarios .
Some SNR margin fluctuation is normal say during evening/busy periods where a gradual decrease of a few db is common . Generally there is also a gradual recovery form this situation.

SNR margin fault conditions are those where
1: there is a sudden drop of a few dbs ,indicating a sudden new noise level on the  line . This can also recover very quickly as the source is switched off.
2: there is lots of very spiky changes of say +-2 to 3db or more continuously or sometimes for short unpredictable duration (REIN)

Regards Jeff