I'm going to use a dish 500 on port 4 of the dish 1000.2 to try and get a better signal on 129. How long can the coax be between the dosh 100.2 and the dish 500? I don't want to pt them side by side and would rather place the second dish in backyard. Also do I have to use dishpro lnb on the dish 500 for it to work?