Propagation that utilizes the E layer of the ionosphere. Since this layer is inconsistently ionized and is lower than the F layers that support more reliable HF propagation, such propagation is more rare. When it occurs (usually in the summer months) it can support long-distance QSOs especially on 6 meters. Sometimes known as E-Skip, a Sporadic-E opening can last from minutes to several hours, depending on the density of the ionized clouds. Click here for an OnAllBands article discussing Sporadic-E, Tropospheric Ducting, and Aurora. The article, by Sean, KX9X, talks about what equipment you will need to take advantage of this phenomenon:
“Sporadic-E QSOs can be made with very little transmit power, if the opening is strong. As far as antennas, while bigger is always better, smaller antennas can have excellent results during good openings. A dipole for 6 meters is only 9’ 4” long; you can make it out of wire and hang it from a tree, or construct one using aluminum tubing, a mast plate and a feedpoint connector. Use hose clamps to tighten down the tubing, and adjust the length for best SWR. For domestic QSOs, a 6-meter antenna doesn’t have to be very high; good results can be had with antennas only 15-20 feet above ground.”
