Grayline Propagation, or Florida to Cocos Keeling on 80m by Ed Callaway N4II
The 2013 VK9CZ DXpedition to the Cocos (Keeling) Islands made 51 QSOs with US Zone 5 on 80m. 21 of these QSOs - more than 40 percent - were with stations in Florida. This presentation discusses several possible propagation mechanisms for this grayline event, and concludes that propagation through the dark ionosphere, rather than along the grayline itself, was the responsible mechanism.
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