When I was doing it I used a two port ROUND DISH for DIRECTV (You would need one for the DISH Network).
Then I run a RG cable from each of the two ports on the SAT DISH to two SAT RCVRs I brought with me from my house.
One SAT RCVR is in the living room TV area and the other SAT RCVR is in the Bedroom Area.
Then I run VIDEO CABLEs from each SAT RCVR to the VIDEO INPUT on each TV in the trailer.
This way I can select either SAT TV or regular CABLE/OTA TV by using the TV REMOTE...
Worked great for a few years but when the NATIONAL BROADCAST came out with their digital TV signals from the local towns I stopped bringing along the SAT TV stuff... We now watch full blown high def digital TV for the NATIONAL BROADCAST TV channels coming from the local towns where we are camping using the OTA BATWING antenna on the trailer. HDTV is free to the public and is easy on the eyes...
Roy Ken