It gets more complicated than that. Both Dish and Directway have taken to providing additional channels by using additional satellites and introducing the need to "skew" or split the distance between them when aiming to get more than one. With Internet two-way via dish, you have to be dead on to the assigned transponder on the assigned satellite and then transmit the 1-watt signal up with a phase shift in signal from received (horizontal versus vertical). That's more than you likely want to know but it gives you an idea of the details involved in setting up the system and reliabily aiming it.
The larger motor homes use mostly Datastorm and MotoSat systems installed by vendors and automatic in their sataellite acquiition and aiming. You have likely seen them in parks or campgrounds. It would take all of that on your roof to do an automatic one, plus modem inside.I note that many of them also have roof-mounted TV domes or remote aiming systems for their television since more than one satellite is usually involved.
To have a system you can also use at home for satellite two-way Inetrnet service, you will be using what is called a "tripod" system. You have to set it up, find the satellite by lat. and long., aim, acquire a two-way signal with the satellite service and then take it all down to move when you move on. That is what I have. It really doesn't take so long once you understand and have done it a few times. I average about 15 minutes getting set up and going and about the same tearing it down. The antenna dish (0.75 meter diameter) and its hardware break down into two pieces. The tripod folds and there are, with mine, three round cement garden pavers to steady it once erect. It all weighs around 50-75 pounds, I guess, and rides in my little rolling closet-trailer. It will run off the generator where there is no electrical hookup. The Internet speeds are not blazing but better than many ADSLs and fast enough for some to use in business, if they pay more than I do for speed and bandwidth.
