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bigbopper's avatar
bigbopper
New Contributor
5 years ago

Modem and RF ingress Interference on ISM band (902-928 MHZ) from smart power meter ?

Anyone else getting thousands of correctibles AND uncorrectiblles on download frequencies between 902 and 928 MHZ?  Like half a million correctibles and 3 million uncorrectibles in 12 hours? 

Our new smart (?) power meter is 2 feet from where the cable drop enters the house.  The power meter transmits completely across the ISM band every few seconds.

I believe it is responsible for all the FEC corrections and errors on the download frequencies that are part of the ISM band being used by our 32 x 8 modem.  No other download frequencies are getting more than a few corrections.

5 Replies

  • Hello. While it is normal to have some fluctuations now and then, you should not be getting that many uncorrectables. Are there any splitters or signals amps on the cable line going to the modem? -Allan Cox Support Forums Moderator
    • bigbopper's avatar
      bigbopper
      New Contributor

      Thanks Allan.  Here's an subset showing the numbers after about 24 hours.  Note the channels above and below the 902-928 range.  There are no amps anywhere.  The cable drop goes from the outside up to the attic where there is a splitter that has at least 3 outputs going to each of three locations in the house.  I have not gone up in the attic to look.  I believe RF interference is more likely right where the smart power meter and the outside cable drop are co-located.  I know the downstream power levels are low, but that is not a problem.  Many of the other 32 downstream channels have much better signals. To the right of the SNR numbers are correctables and uncorrectables in that order.

      18 Locked QAM256 885000000 Hz -9.3 dBmV 36.4 dB 1 0
      19 Locked QAM256 891000000 Hz -9.5 dBmV 36.2 dB 2 0
      20 Locked QAM256 897000000 Hz -9.7 dBmV 35.7 dB 7 0
      21 Locked QAM256 903000000 Hz -9.8 dBmV 35.8 dB 980417 3989287
      22 Locked QAM256 909000000 Hz -10.0 dBmV 35.6 dB 754675 3717438
      25 Locked QAM256 927000000 Hz -11.0 dBmV 35.3 dB 346930 1801558
      26 Locked QAM256 933000000 Hz -11.7 dBmV 34.9 dB 10 0
      27 Locked QAM256 939000000 Hz -12.6 dBmV 34.2 dB 11 0
      • KevinM2's avatar
        KevinM2
        Former Moderator
        Hi Bigbopper, can you please include a link to this forum thread and send us an email at cox.help@cox.com, for further troubleshooting? I would also recommend performing a hard-wired speed test using the Cox website, http://bit.ly/2VsdGbX. Additionally, here's an article which discusses ways to improve your internet experience, http://bit.ly/2Kq4uR5. -Kevin M. Cox Support Forum Moderator