What's the smaller circle on APRS.fi? The larger one agrees with my radio horizon calculations. 73, Steve, K9DCI USN (Vet) MOT (Ret) Ham (Yet) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.tapr.org/pipermail/aprssig_lists.tapr.org/attachments/20121202/d68a9c47/attachment.html>