Originally Posted by jcalabria
Proper system design and maintenance... but even with that there will always be some level variations with temperature swings because all of the plant cable downstream of the last active device as well as your drop cable are thermally uncompensated. A swing of a few dB is normal and to be expected. People can have issues even in a properly operating system when their in-house wiring/splits (quite often done outside of the cable company's purview) put their signal levels right at the edge of working/not working.
All of this is one of the reasons that, even though the spec sheet for most of these STB/DVRs lists -10 dBmV as their minimum signal level for QAM channels, TWC internal spec (AFAIK) is -8 dBmV, and -6 dBmV is an even better target... to allow more headroom for these unavoidable level variations.
In your case, Jack, my best guess would be that your troublesome channels are sitting somewhere between -8 and -10 dBmV when they are working and dropping below that when they are not. Also, since the normal tendency would be for the signal levels to rise during those overnight hours, I would suspect that there is something amiss in the setup of the amplifiers feeding your home and not just normal signal level fluctuations.
I sent a letter to our area Tech Operations Supervisor, with regards to the loss and return and loss and return of these channels for at least the past 6-12 months. We got a new drop line installed, which solved the problem for about a month and a half. Field tech was good. He thinks it's an issue further in the node.
We are in a subdivision that has phone wiring from the 70's. No Joke! When I had DSL Internet, I was getting disconnects all the time. About ten years ago, we had I think AT&T and the guy came out and he basically said, "Your phone lines suck." And it was about that time that TWC, I go WAY BACK with them, they had to replace a line in our node that was like, dead. And when that didn't work, they had to go out and actually put in a new pole/grounding circuits. They linesmen told us, "Your lines are so old in this neighborhood, I wouldn't even use them to tie up my tomato plants!" LOL!
I should have actually gone into the age of our wiring in my letter to the supervisor. But they seem to be doing something. I had a 10 minute loss of Internet and Phone, yesterday, and last night, as well as tonight, two very systematic type reboots of the box, and that has never happened before. A few channels are back, some are still out. Actually, on my MDN box, I had a week of reboots before the box would not boot up at all.
The Internet loss was in the afternoon. The reboot of the boxes was around 3-4am I would say both times. In my letter, I requested 60-90 days of monitoring of those channels in my node.
My question is? What sorts of signal/line related things will the supervisor be testing that a regular field tech could not? I recall a TWC tech told me once that my city has about 36 nodes. Approximately how many cable lines could be in one mode? Would they have to test each line/trap in my node?