I know its really nothing to worry about if I still have connectivity and proper speed, but I'm a curious guy who likes to wonder if there's anything I can do to make a situation better.
That being said, if the downstream SNR on my TM722g cable modem has lowered itself since my X1 installation last month, what could be the cause of this?
In more detail, I have taken the modem and hooked it up before all the attenuation in my house (active 15db forward amp (Antronix) and the splitters after it) and it still has the same SNR value. So it seems to be an issue beyond my house.
The way my line comes in from the tap is:
Tap --50ft-> grounding box on side of house --5ft (to inside)-> Antronix 15db amp --> Commscope 3-way splitter (2x7db + 1x3.5db) --> one line up to my office, one line splits to a 2-way Commscope (2x3.5db) splitter for 2 seperate rooms for TV
In office: Line from basement to another 2-way Commscope (2x3.5db) splitter --> one leg goes to TM722G, the other to a 6 port amp that is only ment for TV connections to be amplified (its a 2 story + basement house that has long runs from my office on the second floor to rooms on the other first floor side of the house).
So in the end, the stats before the amp on the modem are -1-0dbmv downstream power and 34.50dbmv for the 3 upstream channels I have. The stats all the way up to my office are 0-2dbmv downstream (kept balanced by forward amp) and 42.50dbmv for all 3 upstream channels.
SNR stays at 35.60db for lowest channel and highest channel has 37.09db no matter where the modem is located on the drop.
They all were at 37.94db before the install. So unless there is coincidentally change that happened at the tap and beyond, is something going bad? I feel these current stats are the actual stats rather than all channels having the same SNR because each channel is going to have its own variations, right?
Also, I noticed that I would go days before seeing codeword errors with the previous SNR. With my current SNR (even though my codewords are at ~0.00004% of the total octets on each channel), I begin to regularly see codewords errors at about 100 a minute (correcteds of course).
Again, I know all of this is in perfectly acceptable ranges, but as a "small" question out of curiousity, what could cause the SNR to change to these values no matter where the modem is on the line in my house?
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