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Forum Discussion
AP747
Jan 17, 2025Aspirant
Re: Signal Level Check for Xfinity Connected CM1200
Hi can someone advise on whether the downstream signals look acceptable? Ive had occasional drops (few times per month) tied to SYNC Timing Synchronization Failure errors. I read that +/- 7 is the range but Im a littler higher on the channels output and not sure what the difference between the “Downstream OFDA Channels” at the bottom section vs the top section that is labeled “Downstream Bonded Channels” means. Bonded I assume are channels that the modem has locked and actively threading signals. Appreciate any guidance on the outputs respectively.
7 Replies
- FURRYe38Guru - Experienced User
Power levels are too high:
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router
You have too many Correctables that should be zeros like the Uncorrectables.
Please post a copy and paste of the modems event log page.
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-modem-router- AP747Aspirant
Thanks, Please see Attached is a snapshot of the log file
- FURRYe38Guru - Experienced User
Any Criticals, Errors or Warnings seen in the event logs needs to be reviewed and resolved by the ISP. Indicates a signal issue on the ISP line up to the modem.
Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended.Find you a -6dbm coax line attenuator to help reduce the power.
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box.
Be sure your using good quality RG6 coax cable up to the modem.
Start with removing any amplifiers, or splitters from the coax.
From there check the line for kinks, damage, moisture in the line.
Check the connectors for improperly made ends, foil touching the copper coax line, loose connections, bad/old/cheap connectors, or corroded connections. Replace them if you do.
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
https://highspeed.tips/docsis-events/
- plemansGuru - Experienced User
For only having an uptime of 12 hours, that's a lot of errors.
Check all your connections. If you've got a double splitter, try putting that in the line and ensure the barrels are tight.