If you only have one cable receptacle on the outside, you likely do not have satellite prep coax (direct feed to inside receptacle). If only one, it is likely for park cable, which is the same circuit as the antenna and has splitter, ie won't work with sat.
On my rig, I have 2 outside receptacles, "sat in" and "cable". My sat in receptacle sends an independent direct feed to a second independent coax outlet at the main living room TV.
Again, if you only have one outside coax, you will likely need to install a separate outside coax and wire to where you want your sat receiver or modify the existing.
I have wired 4 different trailers for satellite with two receivers and have figured this out. Pm me if you have questions.
Steve
Steve Rinker
Rochester, NY
2013 Keystone Sydney 340FBH 5th Wheel, 12,280 lbs loaded (scale)
2015.5 GMC Sierra Denali 3500, SRW, Duramax, CC, Payload 3,700 (sticker- not scaled yet)
Take my posts for what they are, opinions based on my own experiences.