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[wrs589]

i used the DMT tool on my DG834GT and it shows me these results.



Anyone have any idea what causes the sharp drops around 270, 656, and 760?
Any ideas how to increase stability, other than the usual master socket ring wire etc
Once my exchange is activated for Be (should be this month), ill be switching to them from ADSL24, anyone know how I can improve my line to get more of the potential 24Mbps.

[mr_chris]

The 'usual' master socket ring wire tricks are the usual ones because they are pretty much all you can do to increase the stability of the connection! I take it there's nothing new on http://www.kitz.co.uk/adsl/lowSNR.htm that you haven't tried already?

In fact, until I read what you'd written below the graph I was just thinking how good your graph was looking!!

I'm presuming from reading perhaps too much into that graph, that you aren't having any stability issues at present? I'd be interested to see the line stats too, specifically your error counts.

The sharp drop at 270-ish is the 300kHz "pilot tone", which is present on all ADSL1 connections. The other significant drop is around 400kHz, I don't know what that could be caused by - perhaps tuning a long wave radio into ~400kHz and trying to trace the source of that interference might help, but I don't know. And on the SNR graph it doesn't drop at the same place, so perhaps a red herring of sorts! There certainly doesn't look like there's anything to worry about on that graph, or indeed much that can be done to improve matters at all!

The overall shape of the graph is very good, and shows a nice clean line.

Due to the nature of the beast, it is totally impractical to expect to be able to get rid of all the imperfections and interference on your line - the SNR per tone graph looks like it bodes well for a reasonable increase in speed when you go to ADSL2+, since the high frequencies don't appear to be tailing off too much.

Your line is in much better condition than mine is, and I'm syncing at 9.6Mb on Be. Perhaps someone else will come up with something I've not thought of

[wrs589]

Thanks Mr Chris im surprised how helpful people are!

Later today that 400ish drop is still present.

I can get these stats
Connection Speed     7616 kbps     448 kbps
Line Attenuation    37.0 db    25.0 db
Noise Margin    8.3 db    21.0 db

and these from DMT
Counters        Down            Up

SF:             501971          501969
SFErr:          2               1
RS:             34134074                4265733
RSCorr:         438             8
RSUnCorr:       24              0

HEC:            2               0
OCD:            0               0
LCD:            0               0
Total Cells:    153281699           
Data Cells:     738540     
Drop Cells:     0
Bit Errors:     0               0

ES:             2               0
SES:            0               0
UAS:            76              0
AS:             8533

INP:            0.53            1.00
PER:            1.86            1.96
delay:          4.26            4.50
OR:             30.00           28.44

Bitswap:        0               0


Total time = 2hours 24min 26sec
SF  = 501971   CRC = 2
LOS = 0   LOF = 0   ES = 2

Latest 1 day time = 2hours 24min 26sec
SF  = 501971   CRC = 2
LOS = 0   LOF = 0   ES = 2

Previous 1 day time = 0sec
SF  = 0   CRC = 0
LOS = 0   LOF = 0   ES = 0


How do i get the error stats from netgear dg834gt?

[wrs589]

By moving an AM radio antenae around I found out the source of the interference at 747 is my PC monitor, turning it off makes the interference dissapear, but its not an ideal solution! 

Also, what do the little green lump of frequencys at the left of the top graph refer to? upstream?

[roseway]

Yes, that's what the green section is.

[mr_chris]

*edit* roseway was quicker to post than me

Yep, the green lumps are upstream - which looks like you have plenty of headroom for Be's 1.3Mb upstream too Not sure what to do about the monitor, I guess making sure the router is as far away from it as possible is your best bet.

Not sure off the top of my head how to get error stats from the GT, but you've got them anyway from the DMT info you pasted. Your line is in very good condition, with virtually no errors - 2 CRC, 2 ES (errored seconds), etc... very low figures and certainly nothing to worry about at all.

Like I said before, if you've done all the usual master socket and ringwire tricks, then there's very little else you can do really. But by the look of it, there's very little else that could be done to make that line better anyhow. When you get on ADSL2+, because it stresses the line more, it will show up any imperfections a lot clearer, so it might be worth waiting till you've got Be, then revisiting the DMT graph and looking to see what could be improved then.

Good luck when you get ADSL2+ - I have a feeling you'll be pleasantly surprised with your sync speed - I reckon it should be about 12Mb or close to, anyhow (that's just my personal guesstimate, don't quote me on that!)

[wrs589]

Im actually using an extension sky put in for the sky digibox. Over a few months it seems to be just as stable, and ive checked SNR Attenuation etc and get no impovements on master socket. I tried the ring wire solution but found out behind the faceplate there are no wires connecting it to the socket, my connection is going via the test socket conneciton on the NTE5 faceplate, i think, so I cannot cut the ring wire

Where abouts on that graph would the annex M (upload+) be?

[wrs589]

With interleaving off I now get these stats
Any opinions?

[Ezzer]

Sorry but my laptop isn't diplaying the latest stats

as far as your monitor is concerned on possible solution if a lead is producing the noise would be to try a clip-on ferrite ring

http://www.maplin.co.uk/Search.aspx?criteria=ferrite&source=15&SD=Y

Or check if your current leads have a cylindrical attachment somewhere on them or it hasn't fallen off

[roseway]

You're getting some more errors now, which isn't surprising, but generally that's a very good result if it holds up. If it proves to be a bit unstable (apart from the monitor problem) it might be worth going back to interleaving.

[J.Man]

hmm not trying to be funny but you wanna buy one of my magic filters ??

[mr_chris]

32 CRCs in 1.5 hours isn't anything at all to worry about, IMO...

As long as I'm reading those stats correctly... SF is just a COUNT of superframes - not errors, right?

[Ezzer]

Hang on a Mo' just re-read a post and.....

You have an extention/s yet there's no wiring coming from the back of the face plate ?

Then that means your star wired (you don't live on a new estate not that far from Brundall by any chance ?).

What star wiring in bt speak means is that you have extentions and or a bell connected before the nte.

 the idea of an nte front plate is first it gives you an easy point to connect your own extention wiring,

and if you were to get a problem on normal telephony or now a days broad band, then by removing the plate you disconected all your wiring so you can see if the problem is up to the nte or with your wiring (and so avoid a possible call out charge)

If you've been star wired then removing the front plate will make no difference. what you can do is have a look at the back of the nte. there will be 2 screw terminals marked a & b. each of these should only have one wire each (unless you have a redcare alarm, if so you should have a redcare block terminal nearby)

If there is more than one wire on each terminal then chances are the socket it's running to with have a capacitor within so in effect another master socket and unlike a microfilter set up this could be causing a capacitance inbalance which is afecting your broad band.

You will need an engineer to come and sort this, if it's 3rd party star wiring then it is chargeable, but if it was sky who did this then spring the bill on them as they should know better.

[wrs589]

The extension I'm using now comes from the front of the NTE5 through the socket which is what Sky put in.
There is another extension that was put in a while back when 512Kbps was superfast.

[Ezzer]

I take it the non sky extention is also a plug-in extention as is the sky ?