7800NL SNR Tweaking doesn't work?

Discussion in 'Networking, Telephony & Internet' started by dualmassager, Jan 22, 2011.

  1. dualmassager

    dualmassager Member

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    Just upgraded to the Billion 7800NL from an iConnect 621 and Netgear WGR614 combo.
    Started to do a bit of SNR tweaking with the hidden SNR page as my sync speeds are incredibly slow on my ADSL2+ connection.

    Stats at default SNR settings (set at -1)

    Down Up
    SNR Margin 24.3 24.0
    Attenuation 56.0 31.5
    Output Power 17.4 11.6
    Attainable Rate 3104 624
    Rate (Kbps) 1472 256

    Then I tried to get my SNR margin down and try to increase my sync speeds.

    Set at 50 (-3 dB)

    SNR Margin 24.1 25.0
    Attenuation 56.0 31.5
    Output Power 17.3 11.8
    Attainable Rate 3552 660
    Rate (Kbps) 1472 256

    Hmm, change in Attainable rate, but not in the actual rate and barely any change to the SNR Margin.

    So maybe I need to be a bit more drastic.

    Set at 1 (-5.5 dB)

    SNR Margin 24.2 24.0
    Attenuation 56.0 31.5
    Output Power 17.3 11.7
    Attainable Rate 4160 628
    Rate (Kbps) 1472 256

    Again, change in the attainable rate, but not the actual. But more importantly, the SNR margin remains unchanged :confused:

    On my last shot, I went all out by testing out -12 dB

    SNR Margin 23.3 25.0
    Attenuation 56.0 31.5
    Output Power 16.9 11.8
    Attainable Rate 5344 652
    Rate (Kbps) 1472 256

    WTF am I doing wrong? I also tested out sync speeds on http://www.ozspeedtest.com/

    All the same. 154-157 kb/s.

    Am I missing something? I'm new to all this networking stuff (old router much more n00b friendly)
     
  2. fredhoon

    fredhoon Member

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    If I'm not mistaken, the ISP sets the target SNR at the DSLAM. Therefore setting the SNR on your modem has no effect on your sync as the DSLAM won't go as low as your modem, which is backed up by your results - sync speed stays the same.
     
  3. dualmassager

    dualmassager Member

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    Thanks for clearing that up. Just wondering how others have done so though. Based on the super-reliable Whirlpool forums, many have gotten results from these tweaks (up to 200 kb/s faster). Maybe it's just TPG.

    EDIT: Think the issue might lie with the mode its running. For some reason it's on ADSL_G.dmt, and IIRC, that's ADSL1. Also, a bit more googlin' as found that TPG set their SNR at 6 dB. Might contact TPG helpdesk (god help me :wired: ).

    EDIT 2: Tried disallowing G.dmt. No signal :(
     
    Last edited: Jan 22, 2011
  4. fredhoon

    fredhoon Member

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    When I was last with TPG, I emailed the tech support to change the target SNR at their end. I asked them to increase it from ~ 6 to 10 as I was having stability issues, changed my sync from 21-18mbit.

    I haven't tried changing the SNR to increase speed, however from what i've reaed in other threads, it's entirely dependant on how the ISP configures their DSLAM. Other people should be able to correct me and give you a better answer.
     
  5. thetron

    thetron Member

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    Your speed is locked to 1.5mbit for some reason

    I use to change the ADSL profile on Optus port to a similar speed
     
    Last edited: Jan 22, 2011
  6. dualmassager

    dualmassager Member

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    Hmm, I think might be connected to a RIM sub-exchange. Although the last few times I emailed TPG about the speed, they just told me to do an isolation test. Useless. I've tried the modem at every phone outlet I have. And when I first connected with TPG in '08, I recall speeds slightly faster at 170kb/s. I also doubt it's peak/off peak because these speeds are consistent throughout the day.
     
  7. thetron

    thetron Member

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    You would have to be on Telstra gear rather than TPG owned gear
     
  8. dualmassager

    dualmassager Member

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    Hmm. So if I am connected directly to my DSLAM, it could be because of the super long cable length (est. 3.1 km with 2.3 km sight). Although with the high SNR, I doubt this is the issue.
     
  9. thetron

    thetron Member

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    I don't know your cable length. Something your ISP would have an estimate off or close estimate is ADSL2exchanges.com.au
     
  10. dualmassager

    dualmassager Member

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    That was where I got the figures of 3.1 km. I'll probably send an email to TPG. Could be an issue at their end.
     
  11. hvalac

    hvalac Member

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    I have the same modem and with the tweak I was able to gain around 2.5-3 mbps but as of recent, someone has done something to my exchange (looking at telstra here) and I lost 4mbps (connect at around 10mbps now) which is fucking retarded, I do get the very odd occasion where my net drops and reconnects at 13mbps but so far i've seen that 2 times in 3 weeks.
     
  12. dualmassager

    dualmassager Member

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    HELL YEAH! Sent TPG and email and they must have seen a fault on their side.

    Now:

    SNR Margin 9.1 16.5
    Attenuation 55.5 33.9
    Output Power 0 12.7
    Attainable Rate 4196 792
    Rate (Kbps) 3844 508

    And more importantly,

    Mode ADSL_G.dmt.bis
    :)
     
  13. thetron

    thetron Member

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    Did they say something interesting rather "oh we fixed it for you"
     
  14. evilasdeath

    evilasdeath Member

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    This looking at the fact you were stuck on g.dmt and the speeds was 1472/256 it woudl suggest that you where on a 1500/256k profile as such SNR doesn't determine speed because its set by the dslam.

    Wrong line profile on the line
     
  15. dualmassager

    dualmassager Member

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    Nah, they just told me to do an isolation test (again). I think they don't want to admit the mistake.
     
  16. thetron

    thetron Member

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    Ask them did they change the ADSL profile or not
     
  17. dualmassager

    dualmassager Member

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    Just sent them an email. I'll post back when I get a reply. Gonna try and get them to admit a mistake on their side. It is incredible that I was receiving those speeds just because of a small setting on their end. Two years of this and only now (after a few times ringing up and emailing about the speed) do they see the problem.

    Shame on TPG :thumbdn:
     
  18. thetron

    thetron Member

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    Please don't email them blaming them. Just find out what was the technical explanation
     
  19. dualmassager

    dualmassager Member

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    I didn't directly imply it was their fault, I just want to see why this even happened in the first place. I pay for ADSL2+, therefore, believe it or not, I expect ADSL2+ in return. I know, I sounds crazy. I hope for everyone's sake there is a valid reason for this. I would hate for this to happen to other people.
     
  20. dualmassager

    dualmassager Member

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    Managed to force my connection from ADSL_G.dmt.bis to ADSL_2plus. Gonna see if its reliable or not. It seems to sustain high speed better.
     

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