This looks exactly like what I'm looking for!
The channel master antenna rotor I have came with the remote control unit with an LED readout (0-360). It appears that the numbers correspond with compass angles. For example, if an antenna were installed directly north, you would punch in 000, and if it were south, you would punch in 180.
I had to hit a SYNC switch when setting it all up, and made sure my antenna was pointed the correct direction.
So far, it appears I am reasonably on target, but there is much leeway with local stations, of course. For example, a station with a good signal, that is at 270 degrees may come in at any number between 250 and 310.
I wanted to try this on some distant signals, like the rare occasions I get Sioux Falls, SD or Kearney, NE. Those stations would require a much narrower number range.
With the above link, it looks like I can punch in the lattitude and longitude of my house, and get the approximate 3 digit number I need to punch in. Chances are it won't be right on, but at least I will be able to see if I'm consistently 10 degrees off.
That way if I want to try St Joseph, KC, Sioux City, I can punch in their number and adjust my number by 10 degrees.
I suspect over time and Nebraska Wind, the numbers will drift a bit.
At this point, my receiver doens't have trouble finding stations, so no rescan is necessary.
I went shopping for an HDTV and all I got was a Samsung!