WTW - 11/13/2012 20:10 Interesting webpage! We tried our base information in it and I would say that it fairly accurately predicted where we have coverage issues, even recognizing some of the issues created by bush. 1 watt 900 Mhz radio communication is not always predicatable, especially in fringe areas, or even when comparing directions. We have a field about 8 miles from home where we have been using a portable base because communication to our 95' high system at home is poor. Yet my son drove all the way home from the field and had good coverage from the portable base (at the edge of the field on a tripod). Does not make sense. Wikipedia has some interesting reading about fresnel zones which affect radio communication. http://en.wikipedia.org/wiki/Fresnel_zone Seeing as you have free access to Oregon cors I would think seriously about that if you have good cell coverage. As an alternative you could setup your own base, uploading to the internet and access the correction info the same way you would the cors system. This way you would control the whole system, if that is what you want.