I have a 2015 Georgetown 351 DS.
We have a portable satellite (King Flex which is the Dish/Direct TV version of a Tailgater which is Dish only)
When we camp, sometimes we use the dish and sometimes we use the cable provided by the campground. I wanted a way to switch back and forth without having to totally reconfigure the inside cabinet equipment. (I'll always have to switch from the campground cable to the satellite cable in the storage compartment in the rear - but that's easy)
I wanted to provide this information on how I wired it and report that after testing with both the dish and cable - it WORKS!!
Because the dish uses the park cable jack - the RV TV selector must be set to CABLE.
Unscrew the cable in connection from the back of the RV TV selector and attach it to the IN of an A/B switch
From the B out of the A/B switch- take a short piece of cable to IN on your satellite's control box.
From OUT on the satellite control box - take another short piece of cable to the IN on the Dish/Direct TV receiver.
From OUT on the Dish/Direct TV receiver yet another short piece of cable to go to IN B on a Cable Combiner
From the A out of the A/B switch use - you guessed it another short piece of cable to go the IN A on the Cable Combiner
Finally - with one last short piece of cable go from the OUT of the Cable Combiner to the Cable IN on the RV TV Selector.
Now you can switch from cable provided by the campground to satellite TV by flipping the A/B switch back and forth (plus switching your source in the storage compartment)
Amazon.com: CHANNEL PLUS 2512 DC + IR Passing 2-Way Splitter/Combiner: Electronics
Amazon.com: Coaxial A/B Switch: Electronics
5 pack of short cables