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Sporadic E, often written Es, is the appearance of small, unusually dense patches of ionization in the E layer of the ionosphere. The patches return signals at frequencies far above anything the normal E layer can handle, producing sudden, strong openings on 10 meters, 6 meters and occasionally 2 meters over paths of roughly 500 to 1,400 miles. In the Northern Hemisphere the main season runs from about May to August. Unlike the F layer, sporadic E has little connection to the solar cycle, and simple stations do well in its openings. Read more…