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The K7RA Solar Update

11/05/2010

The average daily sunspot numbers declined again this week, this time by nearly 25 points to 25.7, about half what it was last week. Last week’s average was down about 5 points from the week before, when it was 55.6. Sunspot numbers for October 28-November 3 were 27, 24, 32, 32, 30, 17 and 18, with a mean of 25.7. The 10.7 cm flux was 86.4, 85.7, 84.8, 81.2, 79.1, 78.9 and 78.5, with a mean of 82.1. The estimated planetary A indices were 3, 3, 2, 3, 2, 2 and 4, with a mean of 2.7. The estimated mid-latitude A indices were 2, 2, 2, 4, 2, 1 and 2, with a mean of 2.1.

Look for good conditions this weekend in the ARRL CW Sweepstakes. The predicted planetary A index for November 5-7 is 5, then 8 on November 8-9 and then 5 for the foreseeable future on November 10 and beyond, until November 18-23 when we may see a minor geomagnetic disturbance. For those days, the predicted planetary A index is 8, 20, 15, 10, 8 and 7. The predicted solar flux is 82 for each of the next nine days, followed by 85 for about 12 days. The ARRL SSB Sweepstakes falls during that active period, on November 20-21. This forecast above changes from day-to-day and you can always get the latest update here each day after 2100. Geophysical Institute Prague predicts quiet conditions November 5-9, and unsettled November 10-11.

The latest three-month moving average of daily sunspot numbers shows a steady rise, with the trailing three-month average at the end of June-October at 16.2, 20.4, 23.2, 28.9 and 33. The average daily sunspot number for October was 35, slightly higher than the trailing three-month average, which is a slightly positive sign of an upward trend.

Last week we promised more from Stu Phillips, K6TU, about propagation and WSPR. Stu put together an excellent presentation with his observations, and you can see it along with the comments by Carl Luetzelschwab, K9LA here.

For conditions in last weekend’s CQ World Wide SSB DX Contest, we heard from a number of participants, many operating from well-outfitted contest stations using large antennas, relative to what most of us have available.

First from Jeff, N8II in West Virginia, who reports there was a wonderful 10 meter opening to Europe the weekend before the contest: “The WW was not for the faint of heart here with booming signals from Europe on 20 and 15 with humongous band crowding. On Saturday, I operated from W3LPL on 15 meters and we worked nothing deeper into Asia than Japan in the evening, not even South Korea, but the morning was loads of Qs into Europe including Northern Europe with European Russia right on the edge of the opening. We did have a nice run of Australians and New Zealanders around 2330-0015 after the JAs faded out. On Sunday, I trolled around from home with 15 meters absolutely packed with EU signals including two Europeans trying to run on the same frequency in several spots. Ten never opened well to Europe, but around 1545-1620 Sunday, it came to life working ST2AR, 5R8X, 5N7M, MW1LCR (first EU), GW9T, MI0M, GI4SJA, EI7JQ, and about 3-4 Gs. Earlier, C91M and FY5KE were in on 10 meters, but I never heard them later. There was a very good opening to the south with many loud Argentinean and Brazilian stations on 10 meters starting before 1800 and lasting until about 2130, with closest stations worked being KP2M and two NP2s, along with NP3O. Twenty meters was great during the day, but rapidly declined around 2400 each day.”

Art, VE3UTT/W1AJT, operated from 125 miles northeast of Toronto: “I think that you know that 15 meters was excellent, with long openings even at 43 degrees North. Twenty meters was open late here Friday to 0100 and was good both Saturday and Sunday. Forty meters was noisy both nights; 40 is usually a strong band for me, but a little more difficult this contest. Ten meters was not as good as early in the week when it was pretty much omnidirectional. During the WW, it was open shorter and mostly north-south, with short openings to my east/southeast.”

Doug, K1DG, in New Hampshire reports that “10 meters was a tease -- it “almost” opened to Europe. I worked half a dozen stations in Italy and Germany (and one in the Azores). It was quite good both days to South America and the Caribbean. Fifteen and 20 meters were both excellent, and 40 was good, but a bit noisy. Eighty and 160 were down from last year, and fairly noisy both nights.”

Dan, KB0EO, in Minnesota reports: “We had unusually good propagation for the CQWW contest this past weekend -- good for Minnesota, that is. Twenty and 15 meters had terrific all-day openings worldwide, with contacts made to all continents. It was interesting to be on all day Saturday and Sunday and watch as the propagation moved from east to west. I was also surprised to have a very strong 10 meter opening midday on Saturday to South America -- 10 meters has been pretty dead lately. The opening lasted for about 3 hours and allowed for contacts from Chile to Venezuela. Forty meters was pretty good Friday night into Europe and Africa and solid Saturday morning to Oceana, including numerous contacts with Australia, New Zealand and Japan stations. The flip side was 80 meters had very little activity here -- only contacts into Canada and a few into the Caribbean.”

Bud, AA3B, in Pennsylvania reports, “Conditions were very exciting. I had my best personal results in CQ WW SSB on 160 meters. It was probably the result of a new transmit antenna, but I thought the conditions were good. I thought 80 meters was awful from here to Europe; I struggled with every European QSO. I did have a relative easy time working Zones 29, 30 and 31 from here on Sunday morning. Forty seemed typical. A highlight was a fantastic opening at my Sunday sunrise to Asia -- Japan and Mongolia were S9 here -- I’ve never experienced signals so strong. 20 meters was very nice. Europe was very loud after around 1000 and hung into there until 2200.  Conditions to Asia and Oceania were also better than I remember in recent years. Fifteen meters was my money band.  It opened here to Europe around 1200 and was great until about 1800 both days. There were also nice conditions to Asia and Oceania both afternoons. Ten meters was very exciting and frustrating. North-south propagation was wonderful between 1800 and 2000 both days. I could hear some Europeans and even worked a few, but conditions were not real productive.”

Fred, KH7Y, on the big island of Hawaii operated 15 meters only and reports that this was “the best in years! My first hour was a 300 QSO per hour rate to North America at the same time working CU and Europe with S9 signals. In the late afternoons, I worked many Far East stations like A65, J28, 4X and EY, along with JA and JT. In the early evening, it was ZS, VU, HS and XU. From 0600 to 0800, we had a long path to Europe each evening of the contest, with hundreds of Europeans, even OZ, OH and OX at S9+ for the big guns and S5 for the 100 W guys -- fantastic to say the least. I ended up with 3.1M score with 3152 QSOs in 108 countries and 37 zones for a 24 hour operation.”

Rich, NN3W, in Virginia reported that “conditions were decent. I think the increased solar flux index has taken its toll on the low bands to an extent, as 80 and 160 meters didn’t have the deep openings that I’ve seen in the past. Forty meters was also a bit shorter, but I think that there is a benefit in that the increase in solar flux index has clearly affected the MUF in that we did not have the typical EU 7.0 MHz blackout from 0100-0400 that we have experienced over the past few years. Twenty meters was pretty good, but hard to judge with the interference. Fifteen meters was also pretty good, with openings into Europe for a substantial part of the day starting as early as 1130. I heard some EUs as late as 2200 or 2300. The Pacific opening was good to Australia and New Zealand, with some strong JAs on Sunday (stronger than on Saturday).

“Ten meters was interesting. It was disappointing to see so many packet spots early in the week on 10 with solid openings and to have the door shut by Thursday and Friday. I know we lost one sunspot group and group 1117 was quickly rotating out of view. We had the standard trans-equatorial propagation and north-south starting late morning and lasting into the early evening on Saturday that I caught and worked out a bit; however, I apparently completely missed a good north-south opening on Saturday afternoon (2100) based on what YN2AA told me on Sunday morning, and I was determined not to miss it again. Thus, I pressed a third radio into service on Sunday and just parked it on 28.450 MHz to see what I could hear. Around 1530, noise levels started to pick up and I could hear W3LPL moving around and working stuff. I followed suit and first found 4B2S working W6s (which I could hear very clearly). I worked him and then a VE. I then spun the beam north to work more VEs and found instead an opening to the Mediterranean: IT9s, IG9s and EA8s. I then heard MI0M and worked him. I then decided to set up shop and run. It was clearly some spotlight propagation as I was working GMs, GWs, Gs, EIs and GIs. A second path opened up to Africa which yielded ST2AR, a 5R8 and a ZS. The opening fizzled by about 1700 and I was stuck working north-south again, with lots of LUs, PYs, CEs and CXs. The opening broadened to cover most of the Caribbean and was far enough north to allow me to work a KP2, although I had to beam pretty much due south to land that. I think that if we had about 8 more points of solar flux, 10 meters would have been nuts. But alas.”

Thanks, everyone!

And finally, take a look at an interesting new highly detailed solar image.

All times listed are UTC, unless otherwise noted.

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 each Thursday in The ARRL Letter. You can find a guide to articles and programs concerning propagation here. 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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