7800DXL/DX/VDOX SNR Tweak Table

[billion_fan]

Attached is table with new SNR values for our 7800DXL/DX/VDOX (thanks to our fourms users that helped to confirm the values)

If more values are needed, let me know and I can add them to the table.

Some values may need to confirmed depending on default SNR values.

[swatboy79]

good table

[BadMelonFarmer]

Thanks for posting this!

Totally different from how I "read" the explanation on the GUI, to me it implied that setting a value of 6 would try to sync at 6db, setting a value of 4 would try to sync at 4db.

This table clears up a lot of things and proves my interoperation was wrong.

thanks again.

[Philip_L]

Hi

So is this completely different to the 7800N which is a percentage, i.e. with a 6db profile entering 50 sets it 3db.

Regards

Phil

[billion_fan]

Hi

So is this completely different to the 7800N which is a percentage, i.e. with a 6db profile entering 50 sets it 3db.

Regards

Phil

Yep

[Philip_L]

Hi

Is there a reason for this being different? Using a percentage was much easier to get a handle on . If you wanted to half the set target SNR you entered 50 for 50%, if you wanted to increase it by 50% you entered 150 for 150%.



Regards

Phil

[billion_fan]

Hi

Is there a reason for this being different? Using a percentage was much easier to get a handle on . If you wanted to half the set target SNR you entered 50 for 50%, if you wanted to increase it by 50% you entered 150 for 150%.



Regards

Phil

The 7800N SNR tweak was never based off percentage, check the following link for snr tweaks for the 7800N broadcom solution (http://www.increasebroadbandspeed.co.uk/billion-7800n)

Our engineers stated they changed the SNR tweak to make the standard tweaking feature more easy for non techy people.

[Philip_L]

Hi

The old method works out as a percentage based on a limited range, then seems to go all over the place, as does the new numbers.

I'm not sure the new method is any easier. The ideal would be if we want an SNR of 6db, we enter 6, if we want 10.5db we enter 10.5db. What sense does it make to enter 4092 for 10.5db but 1 for 5db, how is that easier to understand That is even if that table is correct, it is only someone coming up with those figures by trial and error.

Which brings me to another question, why is it that regardless of the old or the new magic numbers, these seem to have never come from Billion directly but have to be experimented with by users to guess at the formula? One of the main selling point of these routers is the SNR tweak options, but it hasn't had any time given to it. At the very least why don't Billion add the magic numbers as an HTML table to the page the settings are made, would take just a few minutes to do and make the world of difference to any one that uses it?

Regards

Phil

[BadMelonFarmer]

Not sure if there is a problem with my line, the way BT do their automatic profile, the ISP, the router...no idea...but....

It seems that what ever I set the SNR tweak to to lower it to a target of say 3, over time (a few weeks I would say) the SNR seems to creep back up to 6 ..... so I have had to increase the amount that the tweak subtracts.

Once my line was fixed due to a connection fault by BT recently, i was getting a SNR reading of about 9, so I subtracted 6 to get a target of 3....all good.

Then over a couple of weeks I noticed the sync rate had dropped and the SNR was back up to 6.... without an SNR tweak it was now 12.... so I subtracted 9 to achieve a target of 3 ... all good

Again a couple of weeks pass and again the sync rate dropped and the SNR was back up to 6 ... without the SNR tweak it was now 15.

Now i understand that SNR can and will fluctuate over time, but it seems a little bit suspicious that it seems to follow this pattern.

for the few weeks when I tweak the line i get rock solid IP Profile and throughput of 4.5 - 5 Mbps, now I am getting 2.5 - 3 Mbps

I have now left the SNR tweak off to see what happens.

[billion_fan]

Not sure if there is a problem with my line, the way BT do their automatic profile, the ISP, the router...no idea...but....

It seems that what ever I set the SNR tweak to to lower it to a target of say 3, over time (a few weeks I would say) the SNR seems to creep back up to 6 ..... so I have had to increase the amount that the tweak subtracts.

Once my line was fixed due to a connection fault by BT recently, i was getting a SNR reading of about 9, so I subtracted 6 to get a target of 3....all good.

Then over a couple of weeks I noticed the sync rate had dropped and the SNR was back up to 6.... without an SNR tweak it was now 12.... so I subtracted 9 to achieve a target of 3 ... all good

Again a couple of weeks pass and again the sync rate dropped and the SNR was back up to 6 ... without the SNR tweak it was now 15.

Now i understand that SNR can and will fluctuate over time, but it seems a little bit suspicious that it seems to follow this pattern.

for the few weeks when I tweak the line i get rock solid IP Profile and throughput of 4.5 - 5 Mbps, now I am getting 2.5 - 3 Mbps

I have now left the SNR tweak off to see what happens.

It seems the BT profiling is kicking in on your line, and keeps trying to achieve a minimum of 6db, you should speak to your ISP about this as the default SNR keep rising (when no tweak is applied)

Ask your ISP to reset your line profile, this should bring the default SNR back to 6db, also ask if a minimum target SNR has been set to your line, and if the BT profiling can be turned off.