Poor signal with Motorola Surfboard Modem

April 2018

I had Comcast (local cable internet supplier) service my exterior line today.
The serviceman used my browser to display the Motorola modem readings at the end of my house line.
  • Enter in your browser address line and hit enter
  • Click on Signal on the left side.

The Downstream Power Level is the most important reading (just remember that -4.0 is better than -10.0). You might still be able to use the internet with a -13 reading but it should be above -10.

SNR (signal to noise ratio) is also important it should be above 33dB.

Readings outside this working range can be caused by a poor signal from the cable supplier or from bad connections (too many splitters) or too long a cable run in your house. Each splitter cuts your Power Level in half. 50 feet of marginal quality or poor connection on the cable might drop the signal by 4 dBmV.

Motorola Surfboard SB5120 QAM 256 (Working range)
Down Power (between -10 and +10 dBmV)
SNR (higher than 33dB)
Up Power (between 30 and 55dBmV)

Thanks to xpcman for this tip on the forum.
Published by aakai1056. Latest update on March 12, 2010 at 10:11 AM by aakai1056.
This document, titled "Poor signal with Motorola Surfboard Modem," is available under the Creative Commons license. Any copy, reuse, or modification of the content should be sufficiently credited to CCM (https://ccm.net/).
Reconfiguring Speedtouch 530 router modem
ZTE ZXDSL 831 - set in router mode