I have a 2014 springdale travel trailer. I bought the Direct tv satellite system. I looked at my TV setup and it has coaxial cable into the TV but it has another coaxial thing with a very short u sh...
One of those two outlets are a direct feed to the park cable/satellite connection on the outside. That is the one you want to feed to your box to have direct isolated feed from the dish to the box. The other outlet on the dual receptacle runs to the rv antenna circuit. If neither one of those work, try running coax from Sat directly to the receiver through the door. If satellite reception works, then you may have a faulty cable connection from the outside receptacle.