I gave a longer answer elsewhere.. Likely to you.
OF all the antennas made for RV use among the worst is the flying saucer designs like the Roadstar
The Best is the Winegard Sensar IV with Sensar Pro module inside the RV (Replaces the wall plate you have now).
There are better antennas but they are designed for home use.
WARNING: All antennas are simple radio antennas.. They do not care if the signal is AM, FM, Digital, Analog, SSB, CW, or some other exotic format (and there are quite a few)... They only care about one thing. FREQUENCY.
ANalog TV used a bunch of Channels (Defined frequencies) Orignally 1-13 then they dropped 1 and gave it to folks like me (6 meter ham band) and added a bunch more so we had 2-83 then they dropped a bunch of the top channels so in the last about 50 years we have had 2-69
with the move to digital HDTV MOST (not all) of the lower channels (2-6 is VHF low) have moved up and many of the VHF channels (2-13 includes both low and high band VHF) have moved to UHF.
SOME HDTV antennas are designed only for UHF and do not perform well at all on 7-13 and do not perform at all on 2-6.. As someone who designs antennas I know why, but..> Well (has to do with the length of the longest element, The lower the channel nubmer the longer the "wing"
Thus the sensar IV (which includes the wingman) is the best RV specific antenna.