Read the FAQs in the FTA section of the forum. Basically, think about it like this - the dish has to stare directly at the equator. The equator is round, just like the earth is, so the dish needs to move in an arc to see the equator just like you have to turn your head to follow the horizon, except the dish isn't looking at the horizon... it's looking above it, at where the satellites are all hovering in the sky in a line called the clarke belt. To really understand how motors work, do some searches for poor man's htoh or poor man's horizon to horizon - that's a manual setup without a dish, where you make the dish sit on a pole that's directly at the angle that matches what a motor would be, and then since the pole is aligned to see the arc, you can tune in the dishes just moving the dish left and right on the pole as skew and elevation are accounted for if it's lined up right...