the first thing to make sure is that you have a digital TV or a digital converter if not. assuming you have that, since it worked in another RV. there should be a Antenna booster located in the RV somewhere, usually in the bedroom.
Most airlines in the United States, including American, Delta and United, allow carry-on bags that are no more than 22 inches long, 14 inches wide and nine inches high. Southwest and JetBlue accept a more generous 24 inches by 16 inches by 10 inches, and JetBlue even adds a couple more inches for cabin bags flying on its Airbus A320 planes.
Unfortunately, there isn't. JetBlue is one of the most generous carriers, permitting you to bring aboard a carry-on bag that measures 24 by 16 by 10 inches. But in 2014, United, American and Delta all changed the size limits of permissible carry-on bags to 22 inches long by 14 inches wide by 9 inches tall. That's an inch narrower than the previous 15-inch wide bag they had all allowed.