Originally Posted by SharkEye80
I installed a Channel Master CM-3016 in my attic that was in storage for at least 15 years (I knew there was a good reason to keep it). I have a clear view of South Mountain which is 20 miles away from where I live,...
...I'm not sure if it's just my imagination, but the SD channels look much better OTA than they did with Cox; HD looks about the same...
CM still makes the best antennae. I am about the same distance and am using twinlead taped to a window, so any antenna that is better and with a clear view could and normally does work perfectly at that distance, other factors depending.
Cox does nothing to degrade HD channels. They demod and demux from 8VSB and remod the baseband digital signal as QAM, so the content remains within the digital domain. They are using VOIP to move it from the receive site to some of their headends, which also does not degrade signals (both processes assuming they allocate enough bits, which they apparently do). Bottom line, it should be the very same quality as OTA HD.
Cox receives HD OTA, but that is being relegated to backup status, as they are beginning to get it from a dedicated fiber feed to each station. KSAZ went just this week. This will not affect PQ either pro or con, but will improve reliability. IOW, when the transmitter has a problem, Cox customers, unlike DBS and OTA customers, will not see any signal interruption. Most stations have transmitter backup, so interruptions should be brief and rare.
Cox used to take SD as baseband feeds from an analog broadcast ring, and distribute it in analog. They have gradually moved to fiber and VOIP area by area which improves quality by retaining integrity during transport, and instead of taking the SD signal as baseband analog, they have begun to crossconvert to 480i and centercut to 4:3 the HD signals and present them as the SD feeds, which also should improve SD. The more they move away from analog and copper plant, the better SD PQ gets.
But the more they wish to divest themselves of analog channels altogether, the more there might be a tendency to overcompress SD (too many SD channels crammed into a single QAM). 10 channels is pushing it, 12 is noticeable. I'm not sure how they are actually approaching it, but SD analog on cable will be gone in 3 to 5 years, if not sooner. Cable wants to reclaim that bandwidth almost as much as the government wants to reclaim NTSC OTA bandwidth.