I work and live near a lot of industries and power lines including very large High Tension Tower lines. I've noticed most of my interference comes between channel 50 and 60. Don't know why. I've also noticed anywhere that two major power line services intersect at or near 90 degree angles is a place to avoid on any channel, stay at least a couple hundred yards away from such an area. I've heard cell phones can cause interference also, but I have not personally experienced it. Just my own annecdotal experience, hope it helps.