I know I am living in the dark ages, a fact verified by my complete lack of understanding most of these posts.
When we had "Classy Chassis" our first bus our TV options were to use the roof antenna to get local. If you did not raise the antenna too high you could receive nearby stations while moving. I guess that was the original in-motion TV. Our second option was to hook up to cable at a campsite.
After screwing with a KVH that was on the bus for far longer than we should have, we finally put a Trac-Star on our current bus, had a local dealer activate the Direct TV and the things has worked without issue ever since. The TV is one of those big old boxes with a glass picture tube but it works. As long as we can get our XM music for rolling down the highway and a few of our favorite Dierct TV channels when parked life is good. From reading the posts I know screwing with what we have appears to create nothing but problems so any plans I may have had to get a newer TV have just been postponed until the current TV dies.
I don't know how it works or why it works, but our current installation doesn't require me to point the remote at anything. Just push a button and it works. I like that because that way we don't need the satellite receiver anywhere in sight. More magic that I don't want to give up. You know we are crossing an invisible line when the electronics become more complex and important than the bus carrying them. Planes have gotten that way also.
A brain dump from a Neanderthal.