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The K7RA Solar Update

07/25/2008

For several days over the past week, we saw a couple of sunspots -- but just like other recent dying Solar Cycle 23 spots, they faded quickly. This group, lasting from July 18-20, was number 1000. No sign of Solar Cycle 24 in recent memory, just a couple of false starts.

There are no predictions indicating more sunspots for the upcoming week. Predicted planetary A index for the near future is 5, with a slight increase to 8 on August 1 and a large increase to 20 on August 8. Geophysical Institute Prague predicts quiet geomagnetic conditions through the end of the month, except July 27, which is quiet to unsettled. Sunspot numbers for July 17-23 were 0, 11, 12, 11, 0, 0 and 0 with a mean of 4.9. The 10.7 cm flux was 65, 65.3, 66.4, 65.9, 66.2, 65.8 and 65.5 with a mean of 65.7. Estimated planetary A indices were 5, 5, 3, 3, 6, 11 and 16 with a mean of 7. Estimated mid-latitude A indices were 3, 5, 1, 2, 5, 9 and 12 with a mean of 5.3.

The autumnal equinox -- the beginning of the fall season -- is less than 60 days from now. I would like to suppose that cycle 24 will be in full swing by then, but we have no way of knowing.

We are still getting regular reports from readers about the continued Sporadic-E activity on 6 and 10 meters.

Going back a few weeks, Mark Lunday, WD4ELG, of Hillsborough, North Carolina, commented: "Amazing the stuff that happens at the sunspot lulls. Actually gives calmer conditions under which to observe phenomenon like gray line prop without the geomag disturbances." That's true; I can recall a couple of years when there was a fair amount of sunspot activity, but month after month we witnessed severe geomagnetic storms that made the HF bands nearly useless, especially at higher latitudes.

Back on July 7 at 0210 UTC, Mark accidentally switched to 12 meters and heard FO5RH (French Polynesia) calling CQ on CW. This was 90 minutes after Mark's local sunset. They exchanged S5 signal reports. Two days later at 2335 UTC, George Pituras, W8KQE, of North Olmsted, Ohio (EN91), worked CT9HZE (Portugal) on 6 meters CW, when George was running 100 W into an omnidirectional loop antenna. The next day he worked Utah on 6 meters, completing 48 states worked using the same loop. He hopes someday to confirm Alaska and Hawaii on 6. He signs his e-mail, "Six meters forever!"

Doug Phillips, W7RDP, of Sammamish, Washington, reports that on July 12 he and a group known as PNW QRP used the call K7S for an annual outing to the Bowman Bay area of Deception Pass State Park on Fidalgo Island. (48.416 degrees N, 122.65 degrees W). In addition to HF, Rod Johnson, WE7X, ran 3 W on 6 meter CW and SSB into a halo antenna 15 feet above his picnic table and worked several Southern California stations in the Los Angeles and East Mojave Desert area.

Jim Henderson, KF7E, of Queen Creek, Arizona, sends us some provocative observations regarding the double solar cycle peaks and possible double minima, mentioned by W7TJ in the July 11 edition of the Solar Update: "The double peak was prominent on the last two cycle maxima. Last minimum showed slight double as well. But I have stated since about mid-2005 that the coming cycle will start after a protracted, double minimum (as in a dip, slight but obvious increase, then dip)." He referenced this Web site.

Jim continued: "Of interest to me (besides the admonition that this minimum is not a record low) is the possible support of Mausumi Dikpati, et als, forecast that this cycle will start late and be '30-50 percent more intense' than is revealed in the plots for the 1933 minimum at the end of this piece. While we need 200+ days of spotless sun to equal 1933, a comparison of the peak of Solar Cycle 16 (approx 80) to that of Solar Cycle 17 (approx 120) shows that it was almost exactly 50 percent higher. Protracted low, followed by a bigger maximum. A bit of good news? It doesn't prove anything, but I am encouraged to continue placing my bet on Ms Dikpati. If I am wrong about Dikpati's forecast and we go into an extended period of low cycles, I will be selling my 10/12/15m antennas and installing a 160 meter Yagi."

Dikpati is reference to a 2006 prediction for a large Solar Cycle 24. See the March 10, 2006 edition of the Solar Update.

Mark Bell, K3MSB from Airville, Pennsylvania, writes. "Just read Jeff Hartley's, N8II, comments about the IARU radiosport contest in last week's Solar Update. For me, the biggest surprise was working 5B4AII (1530 UTC) and TA3D (1635 UTC) on 10 meters CW from Pennsylvania! They were not strong and didn't last too long, but I got 'em. As Jeff said, the HQ stations were beacons on 10 meters."

Regarding 6 meters on June 22, Ed Oswald, W3DUB, of Sinking Spring, Pennsylvania wrote, "Probably not the first mail you got about 6 meters today, but what a morning/afternoon here in FN10. Six was open today here from the time I first got on the radio around 1600 UTC to right around 2000 UTC, first opening north/south with lots of stations heard here and worked from Alabama, Georgia, North Carolina and Tennessee (W3GQ, K4LF, KM4QQ, K4AAK). Stations were booming in S9+ and the band seemed pretty packed. Around 1830 UTC or so, the band started going east/west with Minnesota, Illinois, Iowa and Wisconsin coming in, with K9ZVZ, N2BJ, N0VZJ and N0JJQ worked. I have to say the highlight of my day was the contact with KP4A around 2000 UTC on 50.110 MHz. That was my first "DX" on 6 meters. Altogether a dozen contacts over four hours and 11 grids. Being new here, those 11 were all new, so I'm pretty happy! Not too shabby for 100 W using an 80-10 vertical tuned for 6 (if I say so myself)."

Several readers sent stories from Science Magazine and The Baltimore Sun that have nothing to do with propagation, but are interesting pieces on solar physics.

Amateur solar observer Tad Cook, K7RA, 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. Readers may contact the author via e-mail.



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