To answer your question and not trouble shoot the problem, go to a true electronics store, either a S&B store or an online store and buy enough RG8 coax cable to go from what ever point you wish to use to your Sat. box, a package of F-Type, RG8 compression connectors(3GHz is what I am using), an installation tool, a cable stripping tool and a external cable connector plate.
Determine where you will mount the external connection point, that will determine what type of wall mounting you need to buy. RV supply stores have a wide variety.
Determine how you will run the cable. While RG cables are not as touchy as HDMI cables about bends, I try to have at least a three to four inch radius to the bend.
Depending on the circumstances, I try and run a piece of scrap wire or weed whacker cord through the route I have selected for the coax installation. Pull it back out and buy a piece of cable 10% longer than the routing wire. I pull a pull wire in when I pull the measuring wire out.
Install the exterior coax connector on the cable end, after having dry mounted the outside connector. remove it install the new connector to the back of the plate and reinstall the plate.
Now go inside and allowing at least 12" and preferably 24" of cable in excess of what is need to connect to the satellite box, install another compression F-Type fitting.
Connect the new house cable to the sat. box, the dish to the external connector and you're ready to go.
You may be able to use a factory cable in the RV, if you do, you don't need much of what I suggested, however make sure any thing you buy is exterior grade. Exterior F-Type connectors come with a rubber seal built in.
Good luck and enjoy the show.
"I travel not to go anywhere, but to go. I travel for travel's sake. The great affair is to go". R. L. Stevenson
David Bishop
2002 Winnebago Adventurer 32V
2009 GMC Canyon
Roadmaster 5000
BrakeBuddy Classic II