SIOUX FALLS, S.D. — Ralph Deangelis planned his family's cross-country RV excursion around taking in great sights at Mount Rushmore, Yellowstone National Park and the Grand Canyon. But Deangelis also likes being able to see practical things like local TV weather reports while on the road.

So the switch by broadcasters to all-digital signals on Friday is bringing special headaches for campers like him. Many put off upgrading the TVs in their RVs because it meant tearing up cabinets designed to maximize space, and they're worried now that without over-the-air signals they'll have less access to forecasts and storm warnings.

Deangelis, of Bethlehem, Pa., said last week at the KOA Kampground in Sioux Falls that he'll have to rely on cable-ready campsites this trip, since he hasn't bought a digital converter box to work with his RV's older TV set. He figured why bother, as he already had to remove a faulty rooftop antenna.

Plenty of newer RVs are equipped with satellite dishes, antennae or both — especially the ones people use as summer or full-time homes, with their only TVs. But Mark Thies, service adviser with Spader's RV Center in Sioux Falls, estimates that 95 percent of weekend RVers rely on over-the-air signals.

Lots of people procrastinated because retrofitting RVs with a converter box can be a "total nightmare" that could cost $300 to $400, Thies said. It can involve hours of pulling out cabinetry, rerouting wires and trying to find a spot to mount the box.

"The problem is when they put the TVs in the RVs, everything is built in a confined area, so we have to modify where those boxes go," Thies said. "My recommendation is put in a new TV. That's the easiest, best way."

That can bring the same kind of remodeling headaches, said Darrell Brink, a 66-year-old Sioux Falls building contractor who opted for the converter box.

"The problem with getting a new TV is when you buy the RV, it was built for the TV that came in it," Brink said. "You just can't switch the TV out, because they're built in."

A few sites down from Brink's at Yogi Bear's Jellystone Park, John Luckie of Georgia thinks he has it figured out.

Having a DirecTV satellite dish means he can watch his favorite national channels — but since that account is based in Georgia, he gets only Atlanta's local stations as he travels the country. So if he wants to know if it's going to rain, he switches to use the rooftop antenna connected to his high-definition TV.