09-15-2011 12:22 PM
After moving in to a new apartment in Chicago I signed up for Comcast cable internet. The tech came out and attempted to hook up a new Motorola SURFboard® SB6121 that I purchased from Radio Shack.
The modem continuously rebooted itself, only connecting for a quick moment before restarting in a loop. The tech said that this problem was rampant recently and told me to use a Comcast provided modem while I waited to replace the Motorola. The Motorola modem comes highly recommended by others who have comcast here in Chicago, so I decided to get another off Amazon.
Yesterday I attempted to connect the new Motorola SURFboard® SB6121 to no avail, as it suffered from the same "reboot" problem as the first. I know the cable hook up is good as it works with the comcast modem. Is it possible I have been given 2 duds on a modem that is widely reviews 5 out of 5 stars? Is there another explanation?
09-15-2011 07:08 PM
What are your signal levels? http://192.168.100.1
09-16-2011 02:13 PM
thanks for replying!
i reconnected the motorola, and inbetween restarts it offered anywhere from 0-10 seconds of connectivity, enough time to get some readings:
Here's everything from "signal":
Downstream--Bonding Channel Level
Signal to Noise Ratio34 dB
Power Level11 dBmV
Upstream--bonding channel level
Ranging ServiceID n/a
Symbol Rate5.120 Msym/sec
Power Level24 dBmV
Upstream Modulation QPSK
Signal status (codewords)Bonding Channel Codewords
Total Unerrored Codewords367082
Total Correctable Codewords0
Total Uncorrectable Codewords 509
Is this helpful? thanks for your time.
09-16-2011 02:38 PM
Your signal levels are way out of whack. You need to call for a tech, it's not something you can fix.
09-16-2011 03:30 PM
k. thanks. it's clearly the modem though, 'cause the comcast one they provided works fine. i just don't want to pay the rental fee.
should i bother trying a motorola again? i've heard they have the best speeds, but i'm 0 for 2 now and running out of time.
09-16-2011 06:18 PM - edited 09-16-2011 06:20 PM
Be advised that the upstream power level figure (Power Level 24 dBmV) is not accurate and un-useable as the modem was still in ranging mode when the figure was obtained.
This data ("Ranging Status Other") should say "complete" or "locked" if the modem indeed had sync.
I do agree however that it may be an RF signal/connection quality issue. What do the signal stats look like with the other modem ?
09-16-2011 07:15 PM
thanks for replying.
the provided cisco modem, which is functional, does not offer the same information. when i go to nture/Drama - http://192.168.100.1/ and click either "signal" "status" or "log" it says "This feature has not been enabled in your cable modem." The only information available is under "system" and shows the modem info, MAC address, and:
Software Versionq dpc2100R2-v2.0.2r1256-100817as
Receive Power Level 7.2 dBmV
Signal to Noise Ratio 36.0 dB
Transmit Power Level 44.9 dBmV
Cable Modem StatusOperational
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