Did you try the TV from the house inside camper with the antenna manually raised? Could be the older TV is pre digital. If its an amplified head switch inside needs to be on.
Could be the antenna coax ends are corroded.
Manual & parts for the Winegard antenna.
http://www.winegard.com/kbase/upload/2452013.pdfMechanically easily repairable, sounds like either the elevating gear (unpin the arms, gear is just stuck in the end of tube) or the shaft gear (unscrew inside handle and the large nut on roof, slips out). Ive seen the set screw carve a groove in the hex shaft so handle spins instead of rotating shaft, (though usually something else stuck)
Just parts list
http://www.winegard.com/kbase/upload/wc-790.pdf And parts available direct from Winegard
http://www.winegard.com/sensar/sensar-parts.phpThe whole anttena can be had for a bout $106,
http://www.winegard.com/sensar/index.phpreplacement head for 40..
Unless your near a station cant imagine indoor antenna would be worth its cost. The antenna does not need to be "HDTV" or "digital", some work better but they all work for over the air signal.