Mohu Leaf Indoor HDTV Antenna

My camper came with an amplified omni-directional antenna mounted on the roof. It's marginal at best. We camped last October in a State Park and were able to get a few stations when we arrived mid-week. As other campers arrived towards the week-end, the signal began to deteriorate. Finally we were not able to get any stations until campers began leaving on Monday (Columbus Day). We were staying an extra day and as campers started leaving, our signal improved until it was back to where it had been the previous week. Only thing I can figure is that other campers in the line-of-sight to the TV transmitter were interferring with the signal.