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The K7RA Solar Update


Finally! A sunspot appeared on Wednesday, December 9, giving us a daily sunspot number of 13, following 16 days of no sunspots. And on December 10, the sunspot number was 13. The new group is number 1034, and it is a Solar Cycle 24 spot, as all sunspots have been since number 1016 on April 29-30, 2009. Sunspot numbers for December 3-9 were 0, 0, 0, 0, 0, 0 and 13 with a mean of 1.9. The 10.7 cm flux was 71.6, 71.5, 71.7, 71.9, 71.1, 72.2 and 73 with a mean of 71.9. The estimated planetary A indices were 0, 0, 3, 2, 2, 1 and 0 with a mean of 1.1. The estimated mid-latitude A indices were 0, 0, 3, 1, 2, 0 and 0 with a mean of 0.86.

This weekend is the annual ARRL 10 Meter Contest. Will there be enough sunspot activity to enhance 10 meter propagation? The latest prediction for solar flux shows it rising 75-77 on December 11-12, staying at 77 through December 17, which probably correlates with the new sunspot moving toward the center of the solar disk. To significantly raise the MUF to enhance 10 meter signals over most paths takes more sunspot activity than we are seeing this week, although every bit helps. But this contest often depends on E-skip and the effect of ionized meteor trails during the Geminids meteor shower, which should reach a peak just a few hours after the contest ends on Sunday. Geminids meteor showers have intensified with each passing year as Earth moves deeper into the debris stream from extinct comet 3200 Phaethon. In the Solar Update from January 30, 2009, we reproduced a letter written 34 years ago by Ed Tilton, W1HDQ, the originator of this bulletin. Ed talked about meteor enhanced 10 meter propagation during this contest.

We were watching the current sunspot move toward the horizon a few days ago, via the STEREO spacecraft and wished the whole Sun was visible, which should happen in 2010. Currently, STEREO sees about 86 percent of the Sun. It should reach 90 percent on June 29, 2010 between 0027-0040 UTC, and 95 percent coverage on October 12, 2010 between 1252-1259 UTC. A view of real-time MUF maps shows that during daylight over low latitudes, the MUF is going above 10 meters over the past couple of days.

A couple of 160 meter notes since the recent contest.

Randy Whiting, KC9KHG, of Woodstock, Illinois, says he upgraded to General class in March 2007, and at the time told locals he was putting up a 160 meter inverted V with a 60 foot apex. They told him he would work only two or three hundred miles. The week before last he worked KC7YM in Wyoming, a distance of 1079 miles between their stations. On December 3, he worked G3JMJ, a distance of 3971 miles. Both were on CW.

Markus Hansen, VE7CA, of North Vancouver, British Columbia, writes, "Wow, conditions were amazing during the recent ARRL 160 Meter Contest. I was amazed how easy it was to work New Hampshire, Rhode Island, Delaware, Maryland, Virginia, North Carolina and Georgia from my location here on the West Coast. I am only running 100 W and a very weird shaped 160 meters loop strong around my city-sized lot. The KH6s were bending my S meter in the mornings at sunrise, and JA3YBK was pounding in at well over S9 at 1434 UTC on Sunday. Good fun!"

Hans Goldschmidt, SM5KI, says he is 82 years old and has been a ham for more than 60 years. He is in the center of Stockholm, and "really was shocked when I put up in a nearby low tree an end fed half-wave wire, the feedpoint only 1.5 meters above the ground. Right away I was in a 50 minute long QSO with a station in North Carolina. My signal was S7-9! There seems to be a daily window around 1300 UTC to the Eastern US on 14 MHz and I can work K8SL and others daily with S7-9. In the morning on 14 MHz, we have the usual winter conditions and the band is completely dead right now until about 0700 UTC. Still the same, last week I worked daily SU9HP, a Swede on holidays down there, on 14 at 0730 UTC with Q5 signals every morning when there was almost no other signal to be heard on the band. I say this because despite black-outs and the present sunspot minimum conditions, you may still find a useful path to some DX spot on the globe. Sometimes it is easier to find a rare DX on a dead band. There is also less interference as the competing stations have given up even to try. Years ago I was shocked to hear on 14 MHz two stations, not too strong, on a completely dead band during a blackout, talking, what it seems to be locally. They were in YJ8 and we had an unexpected QSO. Similar QSOs occurred in the past and many were near the equator. Finally a suggestion: Do not give up using the DX bands just because they seem to be dead. There may be short, selective openings to some parts of the globe. Do not rely on those awful DX clusters but listen, listen!"

Thanks, Hans! Good advice.

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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