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CraigP's avatar
CraigP
New Contributor III

Uncorrected and corrected errors

I have Internet Ultimate service with an ARRIS SB6183 modem. I am having errors on only two channels, 74 and 75. Internet speeds are averaging 280Mbps down, 30Mbps up, so it doesn't appear to affecting my service. My signal strength and S/N ratio are on the weak side. Is there an inline amp in my path or a bandpass filter that may be affecting my results? Channel Lock Status Modulation Channel ID Frequency Power SNR Corrected Uncorrectables 1 Locked QAM256 78 759000000 Hz -8.4 dBmV 37.5 dB 0 0 2 Locked QAM256 74 735000000 Hz -7.8 dBmV 35.3 dB 457022 0 3 Locked QAM256 75 741000000 Hz -8.2 dBmV 35.0 dB 3119052 2721 4 Locked QAM256 76 747000000 Hz -8.5 dBmV 37.5 dB 0 0 5 Locked QAM256 77 753000000 Hz -8.2 dBmV 37.6 dB 0 0 6 Locked QAM256 73 729000000 Hz -7.8 dBmV 37.9 dB 0 0 7 Locked QAM256 79 765000000 Hz -9.0 dBmV 37.3 dB 0 0 8 Locked QAM256 80 771000000 Hz -9.0 dBmV 37.4 dB 0 0 9 Locked QAM256 89 825000000 Hz -10.1 dBmV 36.8 dB 0 0 10 Locked QAM256 90 831000000 Hz -9.8 dBmV 36.8 dB 0 0 11 Locked QAM256 91 837000000 Hz -10.1 dBmV 36.7 dB 0 0 12 Locked QAM256 92 843000000 Hz -10.3 dBmV 36.5 dB 0 0 13 Locked QAM256 93 849000000 Hz -10.6 dBmV 36.4 dB 0 0 14 Locked QAM256 94 855000000 Hz -10.9 dBmV 36.2 dB 0 0 15 Locked QAM256 95 861000000 Hz -10.6 dBmV 36.2 dB 0 0 16 Locked QAM256 96 867000000 Hz -10.7 dBmV 35.4 dB 0 0

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  • Tecknowhelp's avatar
    Tecknowhelp
    Valued Contributor II

    It doesn't look like a amp or filter to me. Looks like a bad splitter to me but thats just a guess. The main issue is the downstream SNR is dropping below 36, which is causing the uncorrectables. Don't worry so much about the correctables, you get a lot of those just because of how TCP works. 

    Can you describe how the coaxial gets from the pole/street to the modem?

  • Becky's avatar
    Becky
    Moderator
    Hi CraigP,

    Are there any splitters on the coax connection to the SB6183 modem?

  • CraigP's avatar
    CraigP
    New Contributor III

    There is only one two way splitter (5 MHz to 3GHz)  on the outside of the house where the line comes from the pole and enters my house.  I gained 3db in signal strength by replacing the 3 way splitter that was originally there (lost cable access to my bedroom by doing this). The results are in the post above are AFTER replacing the splitter to the two way splitter. There are no other splitters in line.
    Would it cost extra to have a dedicated line run from the pole to my house just for the Internet? It looks like the tap on the pole has unused ports. Then I could use the existing line for cable access and hook my bedroom back up, and just use a barrel connector ground block to connect the dedicated line to my internet line?

  • CraigP's avatar
    CraigP
    New Contributor III

    Line comes from a tap on the pole, to a two way splitter on the outside of the house. One line runs from the splitter to the modem in my home office, the other line runs to the cable box in my living room. My house at the end of my subdivision, so I wonder if that might be contributing to the lower signal strength and s/n ratio. Everything is functioning except Channel 75 and to a much lower extent Channel 74, it's just that being a geek, I like to see everything in optimal ranges.

  • Tecknowhelp's avatar
    Tecknowhelp
    Valued Contributor II

    CraigP said:
    My house at the end of my subdivision,

    A standard 2 way splitter will lower the signal by 3.5dB. Assuming there isn't too much loss between the tap and the first splitter, then the signal coming from the tap is on the low side. Would it be possible to swap the modem and the cable box and see how the signal changes? Other then that, I think your issue could indeed be related to being at the end of the street. A seperate drop will help, but I think having a technician look at the tap first would be prudent. 

    PS. When buying splitters, 5-1000Mhz is fine. A wider signal pass doesn't get you more signal and can actually let in more noise, which can (but usually don't) cause problems. The most important thing is it has a circuit board interior and a weather durable body. I don't think the splitter is the issue, but FYI.