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Technical Central / Re: Propagation...
« on: July 05, 2013, 11:11:19 AM »Thanks for posting all the information. Reading and understanding prop prediction and values is one thing I really need to work on. Everyone is on the air now talking about a huge sunspot today.
Yes. It is active sunspot region, NOAA AR Number 11785 (or, just 1785). Click on the following image for the larger size...
The sunspot region may start producing x-ray flares, which result in nearly instant radio blackouts on the sunlit side of the Earth. They don't last long; once the x-ray flare is over, the ionosphere begins returning to the pre-flare condition.
Some sunspot flares are also associated with a coronal mass ejection. If the CME is directed toward the Earth (they are not always), then in two to three days after the CME erupts from the Sun, it could cause a geomagnetic disturbance or storm, which lowers the MUF of a given radio propagation path.
cheers...