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Arris SB8200 Channel Values

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Regular 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.


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I am just a customer, volunteering my time to help other customers here in the Forums.
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Regular Contributor

Re: Arris SB8200 Channel Values

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

Regular 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.


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I am just a customer, volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

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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 an employee.
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. 

 


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Regular 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?)

Regular 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.



I am not a Comcast Employee.
I am just a customer, volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark the post as best answer!
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 an employee.
Regular 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?



I am not a Comcast Employee.
I am just a customer, volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

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Regular 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 

Regular 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.  :-)

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

Regular 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.  :-)

 

 

Regular Contributor

Re: Arris SB8200 Channel Values

I guess this does not sound good:

 

8-19-2018, 17:51:6 Warning(5) "Dynamic Range Window violation"
Diamond Problem Solver

Re: Arris SB8200 Channel Values


@Stangeek wrote:

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.  :-) 


Do you not see this page when clicking on the link ";

 

Screenshot.png

From what I understand, they do need to enable / allow you to send them a PM. Perhaps it was overlooked ?

Official Employee

Re: Arris SB8200 Channel Values

Hi Stangeek, thank you for  working with me through private message and glad you hear your services are now back to normal.  Please reach out if you have any questions in the future.

 

Thank you