when it comes to signal reception, two things are king
direction and height
a directional antenna either manual or automatic is better than a Omnni directional antenna
the higher you get the antenna above the roof the better
the one with the best reputation and the most liked is probably the winegard batwing style , I think current version is called the Sensar IV
the PRO version comes with a signal strength meter/amplifier that helps you find the best direction to point it
it cranks up and down from the handle inside the rv
crank it up turn on the tv and the amplifier, and rotate for the best signal
winegard also has a fully automatic enclosed dome style antenna, that mounts on the roof and costs more money, but in really weak fringe areas where the extra crank up height helps, the bat wing gives the best performance