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Intermittent downstream signal-to-noise ratio problems

New Poster

Intermittent downstream signal-to-noise ratio problems

So for the second day in a row, about 1PM est, my connectivity goes straight to the crapper.  I see packet loss to everywhere, and my downstream signal to noise via my modem's page is at or sub-30dB for most channels.  Interestingly, when I am NOT having this problem, my SNR is 40dB or better..  The comcast 'chat tech' just asked me a question about my home equipment.  Really?  I see a hard sudden drop in SNR and you are asking me questions about my home equipment?

 

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Expert

Re: Intermittent downstream signal-to-noise ratio problems

The downstream power and the SNR are way out of spec. As a result, no other downstream channels are being bonded.

 

In a self troubleshooting effort to try to obtain better connectivity , 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.


New Poster

Re: Intermittent downstream signal-to-noise ratio problems

There is exactly one splitter that was replaced by Comcast the last time (6 months ago?) i had similiar problems.  Which turned out to be one of the comcast techs installed a bad splitter at my pole to hook up another house... nice self-inflicted injury there.  By the way, I know you are trying to help and most people that come to this forum probably aren't very tech savvy, but copy/paste replies aren't usually that helpful.

New Poster

Re: Intermittent downstream signal-to-noise ratio problems

And right at 5PM, for the second day in a row, it magically starts to clear up.  It's not 100% yet but slowly SNR will climb...image.png

New Poster

Re: Intermittent downstream signal-to-noise ratio problems

And now, for the first time since 1pm, the snr levels cross back over into at least OK levels.  But they'll go back down tomorrow, don't worry.  Node overloaded?image.png

Expert

Re: Intermittent downstream signal-to-noise ratio problems


wrote:

By the way, I know you are trying to help and most people that come to this forum probably aren't very tech savvy, but copy/paste replies aren't usually that helpful.


For realz ???

 

It's still in the crapper !! The amount of customers on your node has nothing to do with the RF signal strength. 

 

So if none of those tips apply, then book a tech visit as I stated. Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home.

 

Good luck.