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  • latest121511

    12/16/2011 | The K7RA Solar Update

    Solar activity dropped this week, with the average daily sunspot numbers declining more than 39 points to 94.7. It’s been 13 weeks since the average daily sunspot number for the week was that low or lower, when we reported an average of 91.7 in the Septem
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  • latest033111.jpg

    04/01/2011 | The K7RA Solar Update

    The activity we could see recently on our Sun’s far side -- thanks to the STEREO mission -- has been rotating into view, producing some nice sunspot activity and the resulting improved upper-HF propagation. Compared to the previous week (March 17-23), the
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  • latest031711.jpg

    03/18/2011 | The K7RA Solar Update

    The average daily sunspot numbers this week plummeted 45 points to 69, while the average daily solar flux was off over 26 points to 113.1. Sunspot numbers for March 10-16 were 88, 105, 78, 64, 51, 47 and 50, with a mean of 69. The 10.7 cm flux was 131.3,
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  • latest120910.jpg

    12/10/2010 | The K7RA Solar Update

    The average daily sunspot numbers for the week were up more than nine points to 35, and average solar flux rose more than six points to 87.3. These differences compare the dates of December 2-8 with the previous seven days. The average planetary A index d
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  • latest112610

    11/26/2010 | The K7RA Solar Update

    The average daily solar flux declined this week more than 36 points compared to last week, to 24.6. Our reporting week -- which ran until November 24 -- showed the daily sunspot number declining from 40 to 11, but on November 25 the sunspot number rose to
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  • Sunspot081910

    08/20/2010 | The K7RA Solar Update

    Thanks so much to Tomas Hood, NW7US, who wrote last week’s bulletin while K7RA was in California at dance camp. Tomas writes the weekly propagation column for CQ magazine, and he has an excellent Web site devoted to propagation. Tomas mentioned that the A
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  • Sunspot061010

    06/11/2010 | The K7RA Solar Update

    With calmer solar activity, geomagnetic conditions were stable this week. The average daily sunspot numbers were down 7.6 points to 17.7, and the average daily solar flux dropped two points to 71. The average planetary A index declined 6.4 points to 7.9,
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