My modem upstream power levels are high.
Can someone tell me how I can lower them?
The average of my downstream power levels is -3.38 dBm V.
The average of my upstream power levels is 52.9 dBm V.
I have a 6db attenuator installed.
Comcast Xfinity 1 gb cable plan
NETGEAR Nighthawk Modem Router Combo (CAX30) DOCSIS 3.1 Cable Modem and WiFi 6 Router - AX2700 2.7 Gbps
To diagnose and lower high upstream power, follow these steps:
Check Wiring and Splitters: The most common cause is poor home wiring. Remove unnecessary splitters, especially low-quality ones, and ensure all coaxial connections are tight and free of corrosion. Connect the modem directly to the first cable entry point in your home to test if the issue is internal.
Inspect Cables: Replace any coaxial cables that are damaged, sharply bent, or old. A technician can check for resistance buildup or water intrusion in the line, which often causes power levels to fluctuate or rise over time.
Use Attenuators (If Appropriate): If your downstream power is too high and upstream is also elevated, a Forward Path Attenuator can lower downstream levels without affecting upstream. However, if upstream is the only issue, standard attenuators will worsen it; in cases of low downstream/high upstream, an active return amplifier or return path attenuator may be required, though this often necessitates ISP intervention.
Contact Your ISP: If levels remain high after eliminating internal splitters and bad cables, the issue is likely outside your home (e.g., node imbalance, damaged street lines, or faulty amplifiers). Provide your modem’s signal log to the ISP, noting that upstream power exceeds 50 dBmV, which is generally considered the threshold for connection instability.
Is this causing issues, or is it out of spec? If so, you need to get Comcast to figure it out.
A Xfinity tech came by today. He removed the atenuator and both the upstream and down stream power levels are now within docsis 3.1 specs.
Hmmm…
My attenuator was for both up and down.