The K7RA Solar Update


This week's bulletin is presented a day earlier than usual, due to the Independence Day holiday on Friday. The weeks seem to drag on with no sunspots in sight. An image from helioseismic holography on Tuesday shows a spot on our Sun's far side. We hope it emerges in a week or 10 days on our side and hasn't died out by then. Spots emerge from time to time, but they are all old Solar Cycle 23 spots and they seem to fade quickly without much activity. Sunspot numbers for June 26-July 2 were 0, 0, 0, 0, 0, 0 and 0 with a mean of 0. The 10.7 cm flux was 65.4, 66.1, 65.9, 66.6, 66.7, 65.6 and 65.9 with a mean of 66. Estimated planetary A indices were 16, 8, 7, 8, 6, 5 and 3 with a mean of 7.6. Estimated mid-latitude A indices were 17, 7, 6, 7, 5, 4 and 1 with a mean of 6.7.

A reflection of recent activity is the 3-month moving average. With June now over, we now know the average sunspot number for the three months centered on May and it is very low. Instead of rising, the sunspot average has been stalled since late last year around 8.1-8.9 and has now dropped to five.

Here is the table of 3-month averages we present every month -- including the last three months -- centered on May:

Jun 06 28.9
Jul 06 23.3
Aug 06 23.5
Sep 06 21.2
Oct 06 24.1
Nov 06 23.1
Dec 06 27.3
Jan 07 22.7
Feb 07 18.5
Mar 07 11.2
Apr 07 12.2
May 07 15.8
Jun 07 18.7
Jul 07 15.4
Aug 07 10.2
Sep 07 5.4
Oct 07 3
Nov 07 6.9
Dec 07 8.1
Jan 08 8.5
Feb 08 8.4
Mar 08 8.4
Apr 08 8.9
May 08 5

I have no idea when this will turn around; Solar Cycle 23 seems to be unusually long.

While there haven't been many sunspots, this has been an eventful sporadic-E season. Mark Lunday, WD4ELG, of Hillsborough, North Carolina, said he listened to a great 10 meter sporadic-E opening last Friday evening, June 27 between Europe and the upper Midwest and East Coast. 4O3A in Montenegro was one of them, and unfortunately Mark wasn't able to communicate with any of the Europeans. He e-mailed a nice graphic showing a globe with the stations heard and their paths, including the grey line terminator.

Jim Abercrombia, N4JA, of Enoree, South Carolina, worked 4O3A also on Friday on 28.495 MHz at 2100 UTC. Jim says he worked 4O3A again on 10 meters at 1457 UTC the next morning. 4O3A was mostly working Europeans, but a few North American stations as well. Jim has a free downloadable book on antennas that you can get.

Julio Medina, NP3CW, of San Juan, Puerto Rico, sent in an amazing long list of stations he worked in the month of June, all on 6 meters, nearly every day. The calls are from North and South America and all over Europe.

John Butrovich, W5UWB, of Orange Grove, Texas, wrote about experiences during the recent VHF contest: "June 15 during the contest, 2 meters was open for me (EL17ax) for about 20 minutes (1445-1510 UTC) to the NE into EN field. Twelve stations worked on 2 meters. Interesting note: at 1446utc I shifted N0VZJ to 222.1 and we completed at 1212 mi/1951 KM on SSB. Two others called but the MUF dropped. I guess you saw the NA-EU prop on 6 meters today? Perhaps one of the best ever for the northern tier gents. I am too far south and had no Es until 2342 UTC (late for EUs!) and worked MM0AMW SSB on 50.113." You can see some nice photos of John's antennas here.

For some reason, we received no Field Day reports, so I'll give one. I showed up Saturday night with no particular plans at the K7R site in a wooded park in Redmond, Washington. Five stations were widely spaced around an open grassy field surrounded by tall Douglas fir trees, perfect for slinging wire antennas; an archer had slung lines over high branches for the antenna raising earlier in the day.

I stopped at the first station I encountered, right where the trail opened from the woods. This was a CW position, and I think with this particular group CW ops were in short supply. After a while I began operating 20 meter CW, but at some point we had a question about where the beam antenna was actually pointed. Using a mapping program on my laptop hooked to a GPS receiver, I set the map to leave a trace showing the path I followed and I walked from the director side of the beam in the direction the boom was pointed. With the map zoomed in all the way, I could see the path was heading slightly south of east.

Later, when 20 meters died out, I switched to an 80 meter dipole and operated until 2 AM Sunday morning. This was a very smooth operation, as the modern top-of-the-line transceiver automatically switched to the other antenna when I changed bands. It also had built-in CW memories, which was very useful, as my call is K7RA -- very close to the special event call being used, K7R. I think on CW the 1×1 call causes enough repeat requests that any advantage of sending one less character is erased. Propagation over North America was fine and I had a ball. I never did make it to any of the other four stations.

In last week's bulletin, the name and QTH for AD5FD were improperly identified. He is Tom Scott of Schertz, Texas, near San Antonio.

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.