That's how I figured it out. I did a google search and it came back to one of the threads here and it took me a while but I finally was able to do it. I don't have any antenna just the UM150. I am about 5 miles from the 3 towers. One is Alltel and two are Verizon. I have plenty of trees between me and the towers so RevA does seem to work much better then RevO.
