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In article ,
"Lisa Simpson" wrote: "Telamon" wrote in message In article , Radio TexMex wrote: Lisa Simpson wrote: http://science.nasa.gov/headlines/y2006/06mar_solarminimum.htm?list205275 Yup. There she blows, bare as a baby's bottom. NASA solar physicist David Hathaway explains: "Solar minimum has arrived." - So, since that fella said it, I guess its official. This won't stop me from enjoying my hobby, but that damn powerline situtation in the backyard sure makes it hard. Happy DX'ing! This just means that the lower bands will be better than the upper bands. The international broadcasters change the frequencies they broadcast on seasonally and yearly based in part on the sun spot count so it should not affect your listening to a large extent. They smaller broadcasters are not as flexible though so you might lose out there during the minimum sun spot years. Having no long term experience in SWL personally, would those with a couple cycle's worth please share their experiences? What can we expect for the next ~11 years? There are three cyclic things I can think of that affect propagation. 1. The night and day cycle. 2. The winter and summer cycle. 3. The solar minimum and maximum cycle. All three are similar in a way in that the propagation is affected by the amount of sunlight in the hemisphere you reside in. Basically the 11 year cycle will exaggerate the night/day and seasonal effects in a way similar to the tides where when the moon and sun gravitational pulls line up you have the same tide cycle but the levels change is more dramatic. Right now we are at or near solar minimum and so the lower bands are generally better with over all lower levels of solar ionization. As the time of day and season favor the lower bands they will be even better at these times than during the solar maximum. Consequently high band propagation is not as good. The current daytime MUF is not so high this past the winter but was higher this past summer. The daytime MUF will be higher in the solar max winter than this past winter and even higher in the solar max summer than this past summer. Over all, low bands are better these days and higher bands not so good. During solar maximum the low bands will not be so good and the high bands will be much better when the season and time of day favor them. The change in middle bands will not be as great as in the low and high bands going from solar min to max. -- Telamon Ventura, California |