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ctgreybeard
Old dogs can learn new tricks
Premium
join:2001-11-13
Bethel, CT
Reviews:
·Comcast

[Praise] Short outage this afternoon, big improvement!

Click for full size
I had noticed that my correctable and uncorrectable counts were higher than they should be but hadn't noticed any specific problems. I was keeping an eye on them though.

This afternoon, though, the router spontaneously rebooted and when it came back it was much worse. Downstream was too high (10dbm) and the error counts were cranking up quite a bit. After about five minutes, though, the router went offline and rebooted. After that things have been pristine. See the screenshot (9 1/2 hours up time) and notice the errors. They have not changed by one since the modem came back online.

I suspect someone with sharp eyes was watching my router or, probably, many routers on our circuit and decided to do a little preventative maintenance. If so, THANKS!
--
Old dogs can learn new tricks!

andyross
Premium,MVM
join:2003-05-04
Schaumburg, IL
I think you mean modem, not router. Most likely some local maintenance, and they may have taken out an amp or something for a bit.


ctgreybeard
Old dogs can learn new tricks
Premium
join:2001-11-13
Bethel, CT
Yup, modem. And I also suspect they swapped out an amp.
--
Old dogs can learn new tricks!


Streetlight

join:2005-11-07
Colorado Springs, CO
reply to ctgreybeard
Your upstream power level is kinda' high. It's not out of spec, but could get there with environmental changes. When my US power got to higher than 51.5 dBmV, I lost connection. Replacement of the underground coax cable brought it down to a steady 42.5 - 43 dBmV on three bonded upstream channels and absolutely no connection problems have occurred for over six months. Why your US power level is so high may be different from my situation, but it might be worth looking into.
--
There is nothing more deceptive than an obvious fact.

Sherlock Holmes in
The Boscombe Valley Mystery
A. C. Doyle
Strand Magazine, October 1891


bradyr
Columbia College IT
Premium
join:2008-10-27
Sonora, CA
his power levels are similar to what mine are, if I were a betting man, i'd say he's off of a high-value tap, maybe even right off of an amp.

could explain the high downstream power with high upstream power.

I'm right off of a amp, my tap is like a 23v. add about 125' with no splitters and my upstream power is around 47 on two channels and my downstream is about +6 to +7 across 4 channels.


ctgreybeard
Old dogs can learn new tricks
Premium
join:2001-11-13
Bethel, CT
Reviews:
·Comcast
reply to Streetlight
Actually, I did have a lot of trouble this summer and finally got a tech out to take a look. I would reach 57 dBmV occasionally and normally was riding at 55. When it peaked the modem would reboot frequently.

So the tech went out to the box hanging in the street (is that the amp?), opened it up, swapped out a module or two and it brought it back down to 49 at the router. He measured it at the demarc which he said was OK. They also reterminated the cable and replaced the splitters.
--
Old dogs can learn new tricks!


Streetlight

join:2005-11-07
Colorado Springs, CO

1 edit
The sensitivity to various signal parameters seems to vary with modem manufacturer. It looks like you have a Motorola SB6120/6121 which may work well with higher US power levels than my Zoom 5341H.

On the other hand, you said you had problems in the summer when it's generally warmer outside. These may come back when it gets to warm summer temps.

One signal parameter you need to call Comcast to get is the upstream S:N ratio then report it here. Comparison to the specification value may be useful.

You'll surely keep an eye on things as time goes on, particularly if problems occur.
--
There is nothing more deceptive than an obvious fact.

Sherlock Holmes in
The Boscombe Valley Mystery
A. C. Doyle
Strand Magazine, October 1891