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[dene2496]

I got a DG834GT to try and improve my targe SNR situation.  The speedtouch cant quite lower it far enough for my liking plus it seems to randomly reboot at least once a day recently.

However the netgear syncs a lot lower than the speedtouch.   So i ran DMT for both routers and noticed there seems to be a problem with bitloading on the netgear.

 
heres dmt on the Speedtouch 585 v6  (target snr slider set to minimum)...


and the Netgear DG834GT running DGteam firmware....


That looks a bit odd to me.  How is it that the bitloading graph just stops rather than taper out as on the speedtouch?

can someone explain this,  is the router faulty?

thanks

[kitz]

I'm taking it as for granted that this can be repeated and its not a time of the day thing?

Looking at the graph it would appear that the Netgear is not displaying any info about the bins its not actually using, whilst the ST is still continuing to record the SNR for bins even if they arent in use and are too low to actually utilise.  I can think of no other reason why it would just stop like that.

Whilst its hard to see from the graphs for sure, it does appear that the 'actual SNR' readings per bin is slightly higher with the ST even at the lower frequencies which has enabled more bits to be loaded into those particular bins which is what will have given you the additional sync. The ST has also been able to just scrape by and load minimal bits into some of the higher frequencies.

Whilst many people swear by the Netgears (which are good) - on my own line I find that the ST585v6 works best...  I am however very surprised at just how much difference it has made on your own line.  A difference of 1Mb is quite a lot.

[orainsear]

Have you tried the comparison using the standard netgear firmware rather DGTeam?

[dene2496]

Ive reflashed the netgear gt with the latest firmware from netgear.co.uk

though it now seems that DMT will not work with it.   "Can not identify modem type"

ive done a setup.cgi?todo=debug with it before hand. 

Is there a certain official firmware that will work with the GT and DMT?

[dene2496]

ok got it to work by ticking use special login.


Heres the Speedtouch with firmware 6.1.4.3 at 3:05pm...


and the Netgear with firmware 1.02.16 at 3:25pm


Looks like your right about it only displaying SNR for tones it actually uses.  Still seems a big difference in sync rate though.
I think the bst thing for this netgear is to go back on ebay and ill get a spare 585 while i still can. 
It would be so much simpler if i could just get my default target SNR back but i think thats just a dream even though i just want a 3db drop
 
so am i wrong to expect the slider on DMT where it states 10% to actually be 10% or my default SNR (15db) ?

[roseway]

so am i wrong to expect the slider on DMT where it states 10% to actually be 10% or my default SNR (15db) ?

It doesn't work like that. In fact I'm not really sure what the % scale means at all. If you put it right down to the bottom at 1% you will get about 5.5 to 6 dB reduction in the target noise margin.

[kitz]

When I 'played' with DMTv8 I did so with a Voyager 2100, and this is what I discovered on my line (which at the time had the default 6dB Target SNR)

Taken from the main site DMTv8 guide - http://www.kitz.co.uk/routers/DMTv8.htm

Code: [Select]

The slider is not entirely accurate, and because each line is different then you will have to experiment. But as a guide:-

Default New Slider
Target SNR   Target SNR  value % 
     
6dB 3dB 50
6dB 9dB 150
6dB 12dB 200


[dene2496]

ah,around 5db is about right for what its doing.  at least i know its not faulty so back on fleebay she goes.

maybe i'll go sneaking down the exchange tonight with a crowbar...seems to be my only chance of getting my target snr rduced now.

thanks