Some RV's have a dedicated SATELLITE input and coax. The wiring diagram (simple) looks like this:
Input jack on ouside of coach-----Coax----Jack or coax connecter INSIDE coach
Note the only thing between the inside and outside connections is.. COAX. RG-6 to be specific.
The "Cable tv" jack however looks like this
Input---coax-----Stuff--Inside jack
The coax is often RG-59 lowest bidder 59 at that (not nearly as good) and the "Stuff" blocks the signals from the Sat Receiver TO the antenna (Dish/dome) so this simply does not work.
The stuff, is usually a wall plate, with a 12 volt outlet, Switch, Light and Antenna connection, if you remove the plate from the wall the COAX ends at the middle connector on the back, You can use it (With greater signal loss) if you disconnect from the plate.
Alternate "Stuff" is a box of many buttons, Cable will be labeled on the back of the box, same comments.
But if you have a dedicated SAT input.. USE IT.
