Quote:
Originally Posted by Sephiroth
His SNR from an earlier post is 36.17 - that's DS of course.
The high US power arises because the CMTS can't properly communicate with the CM and so the CM steps up power until the CMTS can communicate properly. Ideally Risco's US power should be below 50 dBmv (IMO) and if higher (but below 55) needs to be steady or else he'll have problems as described.
As to re-wiring in the house. The coax is a common medium for US & DS. So they put in a reverse HDU at the original install . Somewhat unusual. How many TV set top boxes (like V+) do you have?
Could you please describe the wiring starting at what's inside your wall box and ending at the cable modem. Which end/port of the HDU goes to the modem? Is there any attenuator attached anywhere? Which model/make HDU have you got?
There are several potential factors that determine the power levels, including but not limited to:
1 Distance to your home from the street cabinet
2 Tap connected in the street cab (attenuation setting)
3 Number and condition (equalisation) of the line amplifiers in the street
4 Condition of the tap providing the drop cable to your home
5 The number of splitters in line
6 The length of internal coax cable in the home
So re-wiring your home means what to you? What is the scope you think is needed?
Let's say you are (like me) 300 m from the street cabinet. I have 3 STBs and 1 CM. An STB splitter is on the outside wall box that disperses to 2 rooms via the outside wall. The cable goes through the wall. There is another splitter - one to an STB and one to the CM. There are no boosters or HDUs. I get the following CM stats on a good cable service:
Downstream Receive Power Level : 1.8 dBmV
Downstream SNR : 37.6 dB
Upstream transmit Power Level : 37.0 dBmV
So, compare your gaff with mine in terms of the parameters I've provided and we can try to move forward from there.
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Wow, nice detailed post. I will let you know tmoz!