Here is a neat pictorial about the cable TV connections...
This is the Antenna Wall Plate that most of us use to connect to the OTA and Cable TV connections...
NOTE that is says you must have the WALL PANEL button pushed that turns off the small LED light to use the CABLE TV connectors at the camp ground pedestal...
Google Image
My two connections that are side by side on the trailer has one labeled CABLE and the other labeled SAT. On my trailer I see no difference whether I use the CABLE TV or SAT TV connectors when I hook up to CABLE TV.. Either connection works the same on CABLE TV receptions from the camp ground pedestals on my trailer... They go to to the same spot I reckon inside my trailer wiring...
I do know that SAT TV operation requires a DC Voltage coming from the SAT RCVR to power up the SAT TV Head in the SAT DISH... When I have ever used the SAT DISH I run my own RG cables directly from the SAT DISH to the SAT RCVR inside my trailer.
The CABLE TV at the camp grounds do not need this DC Control voltage on the RG cable soI have no idea what the SAT TV connection actually does... Never traced it out...
Use a CABLE TV barrel and do a direct connections to your TV set with a 12-foot cable as suggested in the above posts and if that works great then something is not connected properly using the side mounted CABLE connector on your trailer.
Roy Ken