# [SOLVED] Intermittent connectivity drop out COMCAST - Mot SB6121



## Raylo (Feb 12, 2006)

Setup: Motorola SB6121 DOCSIS 3, COMCAST cable out of the ground connected via a butt connector to my CPE cable dedicated to modem, no splitters anywhere (I don't have TV service with COMCAST).

Issue: Few weeks ago I started losing Internet connectivity every day or 2 requiring me to disconnect the coax connection to the modem and power cycle the modem. The little "world" light on the modem is out when connectivity is lost and comes back on after the power cycle and coax disco/reco. All is good for a day or 2, then repeat.

Signal info is as follows:

Downstream snr for bonding channel 2, 6, 7 ,8: 36, 37, 37, 37 dB
Downstream power: 2, 0, 1, 1 dBmV
Upstream power for bonding channel 9, 8, 7: 48, 51, 50 dBmV

Speedtest results ~ typically 18mbps down, 2.75 mbps up (seems slow, a couple months ago would typically get 26/4)

Actions so far: replaced the cable ends on my both ends of my CPE cable.

Anyone have any ideas what might be going on here? Are these readings OK? I am close to calling COMCAST to come out and check their cable. My end looks good but not sure about the box end. COMCAST cable is original to house from 1996.


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## Wand3r3r (Sep 17, 2010)

*Re: Intermittent connectivity drop out COMCAST - Mot SB6121*

You should have nothing between the comcast cable and the modem connection unless its a rg59 patch cable.

a simple call to comcast and they will test to the modem.
have them look at the modem log while in the modem.


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## Raylo (Feb 12, 2006)

*Re: Intermittent connectivity drop out COMCAST - Mot SB6121*

Just wanted to close the loop on this one. I incrementally tried a new connector and then another modem and the modem would still drop offline every day or so. Finally called Comcast... the tech came out and tested the signal parameters and determined that the Comcast cable from their box to my house needed replacement. With the new cable my upstream power levels have dropped dramatically from a variable 42-52ish to 37 plus or minus 1.5. Haven't lost connection since the work was done a week ago. Call this one solved....


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