For the past few days our cable connection has gone out starting around 10am. It is unable to get any upstream channel locks. Around 3pm or so the connection returns. I've been monitoring the connection and notice that in the early mornings the upstream power is around 52 dbmv, and then slowly begins to climb. At the time of this post all 5 upstream channels are around 58 dbmv and have been rising. I expect the connection will drop soon, and when it reconnects later they'll be back to the lower 50s.
I have tried new cables and my spare cable modem and the same thing happens. Any reason these levels would be rising around the same time of day and disconnecting me?
Some stuff to try;
In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test
If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.
i have a single bi-directional 5-1000 mhz splitter coming off the drop with one output going to my cable card tuner (hd homerun prime) and the other to my modem. No coax surge protector on the line, grounding block where line comes in is good. All connections tight, using good quality cables. all other levels and SNRs to the cable card box and modem are good (around 40 snr, 0 dbmv for the 32 downstream data and -7dbmv for digital cable channels.
Looks like I might have to get a tech out to investigate. Seems weird that the power flucuates so much based on time of day. Maybe I'll ask my neighbors if they've had any issues. Thanks for your help!
So this afternoon the connection was still working but I had dropped down to just 1 locked upstream channel and it was at 58 dbmv. I called comcast to get a tech sent out, and she said there's an outage in your area and we can't dispatch a tech until the outage is resolved. I checked a little while later and all five channels are locked and sitting at 52 dbmv. seems like they might have made an adjustment.