What are the upstream and downstream signals? When I log on to my Motrola Surfboard 4200, the signal page reports a downstream level between -3 and plus 1 dbmV. The upstream is between 39 and 53dbmv. When I have severe problems with lost packets, the upstream signal is high, 53dbmV. Does this make any sense?
Generally, downstream should be between +15 and -15 (0=ideal). You look fine there. Your upstream is a bit weird. There may be a bad amp that is affected by the weather, or a poor connection someplace. Upstream uses low frequences below TV channel 2 (54MHz) and is sensitive to noise getting in.
I'm in a similar situtation, as my upstream varies. I've seen it as low as 41, and as high as 61 (it was actually working at 61, too!) I recently rearranged my cabling to eliminate a splitter, and it's been in the low- mid 40's most of the time, but I've see it at 51 once.
Andrew Rossmann wrote in news: snipped-for-privacy@news.comcast.giganews.com:
Thanks for the info. My upstream has been about 45 and I am connecting. When I was having lost packets, I called Comcast. They told me that my router changes the upstream number and that I would have to connect the computer directly to the modem. I was very upset because I don't see how the router can change the contents of message. About that time the the connection improved and I have been connecting well, no help from Comcast. I still don't understand the meaning of upstream and down stream. I am guessing that upstream is what I send, and the down stream is what I receive.
Either the person you were talking to is misinformed or you misunderstood.
That is correct. A high downstream signal level means you're receiving a nice, loud, easy to understand signal (unless the level is *too* high), which is good. A high upstream signal level, on the other hand, means that you're having to shout to be heard, which is bad.
-Larry Jones
This game lends itself to certain abuses. -- Calvin
snipped-for-privacy@ugs.com wrote in news: snipped-for-privacy@jones.homeip.net:
I think the Comcast service people are automatons following a fixed proceedure. Any convenient excuse (like the router changes the message text) to avoid non standard actions will do.
Now I understand. I again guess that the modem invokes a handshaking proceedure to adjust the shouting level.
Exactly. Much like a small child, the modem simply talks louder and louder until it gets a response. Once communication is established, the head end instructs the modem to speak up or quiet down as required to keep its received signal level correct.
-Larry Jones
If I get a bad grade, it'll be YOUR fault for not doing the work for me!
-- Calvin
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