Carl, K9LA, wrote a short paper on topband paths to FT5ZM from near the antipode. interesting. http://k9la.us Look in the 160m link on the left on the home page. Then open or download the file "Arrival Direction of FT5ZM in North America on 160m". It also discusses some 160m basics - the "black hole" in the southwest USA, great circle paths, etc.