Last summer I tried out a 2-bay bow-tie antenna. Bought six 4' fiberglass antenna masts and had the antenna about 24' above the ground. I also used TVfool.com to figure out where to aim the antenna. Worked much better than our Winegard batwing antenna with wingman booster.
I wanted to bring it with us on our current 3 week camping trip but couldn't find the bow-tie anywhere at home. I put it somewhere so it couldn't get damaged and I guess I did a good job of it. :M
Sometimes you can't get a sat signal due to trees and obstructions and sometimes CG cable is cr@p. It's nice to be able to get some OTA channels when you can't get TV otherwise. I've found that sometimes you get some great OTA channels & shows you can't get on cable or sat.
As mentioned, an antenna amp will NOT improve an already weak signal. The amps are supposed to me mounted at the antenna and they are designed to compensate for signal loss in the co-ax from antenna to TV. We have a Winegard SensarPro signal finder but I find it doesn't help a whole lot. I find that TVfool.com is better so you know where the originating TV transmitters are located and can aim accordingly. It also tells you what the signal strength of various stations is.
I'd love to try out a large yagi style antenna but they're too big and fragile to travel around with. The antennas with a rotator that claim reception up to 150 miles are a waste if $$ and contradict antenna wave theory.