On Sun, 21 Sep 2008 15:17:39 -0500, Bruce Jungwirth wrote: >In the world of EMC, the usual formula for the far feild is anything beyond >lamda / 2*pi. Some say 1/2 wavelength or more. Take your pick. This isn't EMC. For antenna directivity, I'd want to be at least a wavelength, preferably two. 73, Jim K9YC