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mdempsky's profile

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2 Messages

Mon, Jul 14, 2014 11:00 AM

Recurring outages late at night

Last night around 3AM (PDT) my Internet service abruptly went out.  I tried rebooting my modem and router and no effect: the "US" LED on the modem just kept blinking.  I could ping my router and the local network side of the modem, but not  This is a recurring problem I'm experiencing: very frequently when I'm working late, my Internet service goes out for hours, and then returns by morning.


How do I track down the cause and stop the disruptions?  Could it be from scheduled maintenance or something?  If so, am I able to have Comcast notify of these maintenance periods in advance and let me ask to have them rescheduled to a more convenient time?


Accepted Solution

New Member


2 Messages

6 years ago

Sorry for the late response. Where would I find the log entries? I have an SMC3DG cable modem, and I can't find anything related to logs in the admin menu. Included below are the downstream/upstream signal stats.


Downstream Channel

Downstream Frequency626.998047 MHz639.000610 MHz645.001831 MHz650.998535 MHz
Lock StatusLockedLockedLockedLocked
Modulation256 QAM256 QAM256 QAM256 QAM
Symbol Rate5.360537Msym/sec5.360537Msym/sec5.360537Msym/sec5.360537Msym/sec
Downstream Power4.077757 dBmV3.158454 dBmV2.840363 dBmV2.815800 dBmV
SNR37.355988 dB37.355988 dB37.355988 dB37.935909 dB


Upstream Channel

Upstream Frequency23699556 Hz30599522 Hz36999405 Hz
Lock StatusLockedLockedLocked
Symbol Rate5120 KSym/sec5120 KSym/sec5120 KSym/sec
Upstream Power39.0000 dBmV39.7500 dBmV40.7500 dBmV
Channel ID747576

Gold Problem solver


610 Messages

7 years ago

yeah, the "US" light continuing to blink means that the modem isn't receiving a signal well enough to start connecting. This generally indicates some line quality issues at your home/business, or on the poles around it. Or, it could indicate a failing modem. It could potentially be because of some scheduled maintenance, though probably not if this keeps happening regularly.


Could you possibly post your modem signals and log entries? You can find those generally at,, or They may help us track down the cause.