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.
Baggage must meet carry on size limits (approximately 22 x 14 x 9 or 56 x 35 x 23 cm). Reference size check templates located at ticket counters and gates. Passengers traveling on Delta Connection flights, and only those flights with fifty (50) seats or less, are only permitted to carry personal items on board the aircraft due to limited overhead space. Personal items must be able to fit securely under the seat in front of the passenger.