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Arris SB8200 Channel Values

Contributor

Arris SB8200 Channel Values

Hello.

 

My area seems to be getting bad again.  The upstream channel power is creeping up:

Screen Shot 2018-08-07 at 3.37.42 PM.png

Since my prior attempts at getting help from Comcast on this have not worked, does anyone have a good strategy on how to get them to fix?

 

Thanks.

Expert

Re: Arris SB8200 Channel Values

Your picture seems to be broken.
Contributor

Re: Arris SB8200 Channel Values

No one can see it?  I see it here in the post.

Contributor

Re: Arris SB8200 Channel Values

Screen Shot 2018-08-07 at 3.37.42 PM.png

Screen Shot 2018-08-07 at 3.37.42 PM.png
Expert

Re: Arris SB8200 Channel Values

All I can see right now are your Upstream levels which are borderline in the first one and too high on the others. If you have any splitters, try temporarily bypassing them to see how it goes.
Expert

Re: Arris SB8200 Channel Values


@Stangeek wrote:

No one can see it?  I see it here in the post.


Some images need to be manualy approved before they will show up publicly. You didn't do aynthing wrong.  I asked someone to apporve the image(s}. Smiley Happy

 

Start here: troubleshooting guide. If you still need help, please post your equipment details (make/model of your modem/gateway/router) and a screenshot of your signal levels and your error/event log.  (If you haven't already) Thank you!


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Expert

Re: Arris SB8200 Channel Values

 

Yeah, I can only see the Upstream levels as well.

 

The upstream power levels on my SB8200 used to be like that until I moved it to a different location, bypassing what turned out to be a problematic stretch of internal wiring.

 

You could try connecting the modem to the demarcation point where your cable enters your home and see if the problems persist. 

 


"The one thing that you have that nobody else has is you. Your voice, your mind, your story, your vision. So write and draw and build and play and dance and live as only you can." - Neil Gaiman
Contributor

Re: Arris SB8200 Channel Values

Thanks!

 

The cable was put in from the street to the point it enters my house in July 2017 by a Comcast technician.  It has one splitter only that splits the signal into 4 outlets.  The cable modem is only 5 feet of cable from the splitter.

 

Of course, if I remove the splitter, the upstream signals will improve, but what practical solution is that?  I would not have any TV signal to the cable boxes, if the splitter is removed.

 

I used to have an amplifier (put in by Comcast).  But with that in place, the downstream power levels get out of spec ---- close to 15 dB!

 

The upstream power levels seem to be below 50 dB for a while, but something happens (maybe the comcast amp at the curb?)

Contributor

Re: Arris SB8200 Channel Values

These are the downstream levels....all seem good.  And the current log.

 

Screen Shot 2018-08-08 at 8.55.08 AM.png
Screen Shot 2018-08-08 at 8.55.49 AM.png
Expert

Re: Arris SB8200 Channel Values

Just out of curiosity, how long has it been online? The uncorrectables seem quite excessive as well. The T3 errors prove an issue. If you can see the line from the splitter to the modem, what condtiondoes the line look? If it looks ok, at that point I would think you might need a technician visit to rectify the upstream problem.

Expert

Re: Arris SB8200 Channel Values

@Stangeek

Your power levels are all well within specification, even your upstream (+54dBmV is the upper limit.) Your modem will actually perform fine beyond that as long as you have a clean signal. And that is your problem, the error correction reporting and error log are indicating a noise issue. This could be something as simple as a bad connector or a bad line to your house. If everything looks physically fine to you, you'll probably need a tech to sort it out. 

 

 

I've asked a Comcast employee to help you. You should expect a reply in this thread. 



 


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Contributor

Re: Arris SB8200 Channel Values

Thank you all for your responses.  I decided to replace the cable from the splitter to the modem with one of the cables that has come with my Xfinity cable boxes.  I think the upstream levels have improved a lot!

 

 

Screen Shot 2018-08-08 at 10.09.45 AM.png
Expert

Re: Arris SB8200 Channel Values

Those are better. Did you happen to reboot it after that?

Contributor

Re: Arris SB8200 Channel Values

Yes.  The modem did get unplugged from power for about 2 minutes and the plugged back in.

Official Employee

Re: Arris SB8200 Channel Values

Hi Stangeek, I can help review signals on my side with you. Could you please send me a private message with your full name and phone number?

 

Thank you 

Contributor

Re: Arris SB8200 Channel Values

Thank you, comcastPhill.  After 5 minutes of looking around this site on how to send a PM, I gave up.  If you have some guidance on that, I welcome it.

 

After a week, the upstream power levels all went back into the low 50s, so now I am not really sure the change of cable did anything.  It seems the levels just creep up and when the modem is power cycled, the "test" returns lower upstream levels.

 

So, maybe I just need to unplug the modem every week.  :-)

Silver Problem Solver

Re: Arris SB8200 Channel Values

Send a message-2.jpg

Do you see "Send a message" when you click on the poster's name? 


I am not a Comcast employee; I am just a customer, volunteering my time to help other customers here in the Forums.
Diamond Problem Solver

Re: Arris SB8200 Channel Values


@Stangeek wrote:

After 5 minutes of looking around this site on how to send a PM, I gave up.  


Here's a direct link to his PM inbox;

 

https://forums.xfinity.com/t5/notes/composepage/note-to-user-id/5932396

Contributor

Re: Arris SB8200 Channel Values

Well, maybe I am just not allowed to send PMs.  That link took me to a page with only a label of "Private Messages", and it seemed to be for my PMs.  :-)

 

 

Contributor

Re: Arris SB8200 Channel Values

@RobertWy No, I do not see that button to send a message to ComastPhill.


@RobertWy wrote:

Send a message-2.jpg

Do you see "Send a message" when you click on the poster's name? 


 

Silver Problem Solver

Re: Arris SB8200 Channel Values

It may be hidden by a contrast setting in your browser.  I installed a Chrome extension for High Contrast.


I am not a Comcast employee; I am just a customer, volunteering my time to help other customers here in the Forums.
Diamond Problem Solver

Re: Arris SB8200 Channel Values

From what I understand, he may have to allow you to send him. Perhaps he forgot to enable it ?

Silver Problem Solver

Re: Arris SB8200 Channel Values

It is enabled for everyone.


I am not a Comcast employee; I am just a customer, volunteering my time to help other customers here in the Forums.