You should have 2 wall plates. One has a 12V power receptacle, a cable connector and a push button. The TV connects to that one.
The other wall plate has 2 cable connectors. One connector goes to the cable connector outside the camper. The other connector goes to the cable input behind the wall plate with the 12V power connector.
With the jumper in place the outside connector is connected to the TV when the push button is OFF (not lit). This is how you are set up for cable.
To use a satellite receiver you remove the jumper. One connector (usually the top one) goes to the satellite input on the satellite receiver. The other connector goes to the TV output connector on the satellite receiver. Again the push button is OFF (not lit). The satellite dish then connects to the outside cable connector.
The push button turns the roof antenna amplifier ON. It should be on when using the antenna and not cable or satellite.
Hope this helps you understand it.
Chuck - Sparta, TN
2012 Jay Flight 22FB, 2 x Honda EU2000i
2013 GMC Yukon XL Denali AWD
EDUCATION is what you get when you read the fine print.....
EXPERIENCE is what you get when you don't.