LF: The Sun on Loran

[MarkusVester@aol.com]

Dear LF group,

the recent bursts of solar activity have also left their footprints on 100 kHz propagation.
http://freenet-homepage.de/df6nm/LoranView/LoranView_2006.htm 
now has links to the November and December monitoring results, side by side with solar x-ray flux plots from the Space Environment Center archive http://www.sec.noaa.gov/ftpmenu/plots.html . The Loran-C data are presented at half size. By postprocessing the original bitmaps, quantitative data like fieldstrength or phase plots with 5 minute / 44 µs resolution can be generated here.

Generally, all C-class or stronger x-ray flares impress phase and amplitude transients on signals travelling on sunlit paths - nice examples are Dec 5, 9 and 14. One extraordinary event took place on Dec 13 03:00 UT, when nighttime propagation on northern paths was suddenly and deeply affected. It was presumably caused by a burst of high energy protons, impacting into the polar region about half an hour after the X3 flare.

73 and best wishes
Markus, DF6NM