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The K7RA Solar Update

09/12/2008

A new sunspot -- number 1001 -- emerged on Thursday, September 11. It is actually a single group with two small magnetic disturbances; we hope it is not another like the last sunspot, a weak one that barely emerged on August 21-22. That spot was so small that some observatories didn't count it, but it was a Solar Cycle 24 spot.

August was much ballyhooed as the first time since 1913 that there was a month or more between the most recent sunspot appearances. Actually, it was the first time that a whole calendar month went by with no spots. Of course, this doesn't really mean anything more than any other 30 day period with no spots because the calendar is based on arbitrary beginnings and endings.

Sunspot numbers for September 4-10 were 0, 0, 0, 0, 0, 0 and 0 with a mean of 0. The 10.7 cm flux was 65.9, 65.2, 65.8, 66.6, 67.1, 67.1 and 67.2 with a mean of 66.4. Estimated planetary A indices were 33, 7, 7, 8, 8, 6 and 4 with a mean of 10.4. Estimated mid-latitude A indices were 17, 7, 7, 7, 9, 4 and 2 with a mean of 7.6. The US Air Force predicts planetary A index for September 12-17 at 5, 8, 20, 12 and 8. Geophysical Institute Prague predicts quiet conditions September 12, unsettled September 13, unsettled to active September 14, unsettled September 15, quiet September 16, quiet to unsettled September 17 and quiet September 18.

John Shannon, K3WWP, of Kittanning, Pennsylvania, has made it a point to work at least one station a day for over 14 years using QRP CW and simple wire antennas. He notes that although he can work more DX at Solar Cycle maximum, propagation on a day-to-day basis is more reliable at solar minimum because it lacks the extreme geomagnetic storms that appear more often during greater solar activity.

Reg Beck, VE7IG, of Williams Lake, British Columbia, writes that he had a productive 6 meter summer season, including working 20 JA stations from 0113 UTC-0143 UTC on July 12, and 368 6 meter contacts overall from July 8-August 16. Reg says propagation is great recently, and he has been running pileups of Europeans in the morning on 20 meter SSB and CW. On August 26-29, he worked 41-45 stations a day, then 106 on August 30 and 84 on September 3, all in sessions from 20 minutes to less than an hour. Reg is north of 52 degrees north latitude, far enough north that around the summer solstice, sunrise to sunset is 1200 UTC to 0421 UTC.

Flavio Archangelo, PY2ZX, of Jundai (in northeastern Brazil), says he has been having good luck with just a 20 meter dipole. Last Saturday, September 6, he worked several stations in Spain around 1830 UTC, then some stations in Denmark at 2000 UTC -- all were loud portable stations working Field Day. Around 1930 UTC, he heard strong German stations, as well as stations in Switzerland stations, then signals faded after 2015 UTC, but stations in Sweden and France could still heard.

Amateur solar observer Tad Cook, K7RA, of Seattle, Washington, provides this weekly report on solar conditions and propagation. This report also is available via W1AW every Friday, and an abbreviated version appears in The ARRL Letter. Check here for a detailed explanation of the numbers used in this bulletin. An archive of past propagation bulletins can be found here. You can find monthly propagation charts between four USA regions and 12 overseas locations here. Readers may contact the author via e-mail.



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