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 Previous: Northeast Amateur Radio Volunteers Aid Massive Storm Response, Recovery |  Next: The Amateur Radio Crossword Puzzler |
BOISE, ID, Apr 20, 2007 -- We are on the road in the Gem State this week -- another with few or no sunspots. Most days had zero spots, but from time to time a new sunspot will appear, but only briefly. If you go to the table of sunspot readings, you can see the brief interruptions in the string of no-sunspot days. Visit SpaceWeather.com and in the upper righthand corner you can dial back to see sun pictures and reports from any day. For instance, there was a brief sunspot appearance on April 14, and if you go back to the April 15 issue of Spaceweather.com, it notes the brief appearance.
Expect more of the same conditions, with few or no sunspots. Eventually this year we should reach a point where the only place for solar activity to go is up.
Today, April 20, we may see unsettled geomagnetic activity. Geophysical Institute Prague expects unsettled to active geomagnetic conditions for April 20, unsettled for April 21-22, quiet to unsettled on April 23, and quiet April 24-26. The US Air Force predicts April 28 as the next date for active geomagnetic conditions, with a predicted planetary A index of 25.
Paolo Battezzato, N1XOI, in Westford, Massachusetts, northwest of Boston, sends an interesting report from April 1 of a PSK contact, and he says this is no April Fool's joke:
"I was working PSK31 around 2245 local time when I saw a very weak signal on my DigiPan waterfall display. I clicked on the trace and read Pablo, AY7X. I'm intrigued by the call sign, so I try to reply to his CQ and after few attempts I contact him. Imagine my surprise when he tells me he is with a DXpedition in Tierra del Fuego, in FD55sd. Not bad from my FN42go grid, almost 11,000 km. By the way, did I mention I have a resonant 20-meter attic dipole, and I was transmitting with just 3 W?"
Great story, Paolo, and I understand many PSK operators are using simple gear with low power and even indoor antennas. In my experiments with PSK I've been amazed at the signals it digs out of the noise.
Barry Roseman, W0LHK, of Stilwell, Kansas, mentioned that during the recent N8S operation from Swains Island, he worked the DXpedition with 80 W SSB on several bands, including on 12 and 15 meters using a 60 meter inverted V.
Ken Kopp, KK0HF, of Topeka, Kansas, sent a link to an article from physicsweb that proposes a much more modest prediction for Solar Cycle 24 than the big one predicted last year by Dikpati et al. This article predicts a cycle 35 percent weaker than the current one. As Ken wrote, "Let's hope these guys are wrong!"
Jeff Lackey, K8CQ, of St. Simons Island, Georgia, is living in a neighborhood governed by deed covenants, conditions and restrictions -- CC&Rs -- that limit his ability to install outside antennas. But he may have happened upon just the right magic rain gutter configuration. He writes:
"I use a gutter antenna and 100 W. The gutter has five downspouts, spaced over approximately 90 feet distance as the gutter zigzags around the back of the house. I feed the center downspout against a ground plane of 16 ground radials. Since January 1, 2007, I've worked 33 zones in 121 countries. The gutter loads up fairly well even on 160, where I've worked 34 states. I've worked Chagos on 80, about 10,000 miles. Yesterday I worked Swains Island on 12 and 17. And a couple of weeks ago I caught Kermadec. So the DX is there. You just have to be patient.'
That is quite an inspiration at the bottom of the solar cycle.
For More Information
For more information concerning propagation and an explanation of the numbers used in this bulletin see the ARRL Technical Information Service Propagation page and the article "The Sun, the Earth, the Ionosphere: What the Numbers Mean, and Propagation Predictions," by Carl Luetzelschwab, K9LA. An archive of past bulletins is on the ARRL Web site. The propagation charts that formerly appeared in QST now are available on the QST Propagation Charts page on the ARRL Web site.
Weekly Sunspot Numbers
Sunspot numbers for April 12 through 18 were 0, 0, 11, 0, 0, 12 and 11, with a mean of 4.9. The 10.7 cm flux was 68.3, 68.3 68.2, 69.3, 69.3, 69.2, and 68.8, with a mean of 68.8. Estimated planetary A indices were 8, 2, 4, 4, 1, 8 and 9, with a mean of 5.1. Estimated mid-latitude A indices were 7, 1, 3, 2, 0, 6 and 6, with a mean of 3.6.
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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