This is based on my experience with my unit. Results may vary.
There are three systems here: 1) Antenna and cable, 2) Roof mounted satellite, 3) Ground based satellite.
1) The switch is used to switch between antenna and cable.
2) Dish 1 & 2 are the roof mounted satellite channel 1 & 2. One goes to living room and other to bedroom.
3) Grndbase 1 & 2 are the ground based satellite channel 1 & 2. One goes to living room and other to bedroom.
Bed1 is for antenna/cable feed to the bedroom.
Bed2 is for the satellite feed to the bedroom.
One note, my satellite is not SWM capable. It has three channels but Peterson Industries only wired two in the trailer. It take three channels to watch TV in both rooms and tape a different TV channel on the DVR. We can watch a show or tape a show in the living room, but not both at the same time. Unless of course we want to tape the same show we are watching.