I had a 6000 in my motorhome.(I am a fulltimer)I am replacing it with a 921. I have a Winegard automatic dish. When I park, I push a button and it finds 119 sat. Then when I punch a channel that is on 110 it turns to it. It fools the receiver into thinking it is a dual LNBF.when I do the check switch thing it shows up as SW-42. I downloaded the 921 manual so I could study it while I,m waiting for the receiver. I see they say to hook a feed from each lnbf to two different inputs. Can I hook up to one input as I only have one cable? Also I have another dish on the roof. Can I hook it to the other input and aim at the 148 sat so I can get all the HD channels?