James
You brought a good article about HF propagation, however the behavor on 160m is different from HF. If you check on the KL7A arcticle figure 1 what is happening between 1 and 2 MHz you can see that the green and red does not behaivor the same way as above 2 MHz. This subject is more complex because there us no shirt answer, actualy between 1 and 2 MHz. the ionosphere does not support linear polariration wave. The wave are actualy eliptical and not circular for most directions. You can check the long answer on the "must read book" from NM7M . R Brown 'The Big Gun's Guied to Low Band Propagation" . Magneto-iomic Theory pag 47 to 56 ; and Power coupling pag 57. Thanks to Karl. K9LA, the book is available on his also must read site on the 160m link http://k9la.us/html/160m.html Regards JC N4IS _________________ Topband Reflector Archives - http://www.contesting.com/_topband