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The K7RA Solar Update


Two new sunspot groups -- 1050 and 1051 -- appeared on February 23 and 24. We've now seen 38 continuous days with sunspots (including today); the last time there were no sunspots for two or more days in a row was back on November 23-December 8 when we saw 16 days with no sunspots. If sunspots continue through Sunday (they will!), February will be the first calendar month since January 2007 with sunspots every day. Sunspot numbers for February 18-24 were 17, 23, 19, 17, 14, 31 and 40, with a mean of 23. The 10.7 cm flux was 85, 83.7, 83.8, 83.5, 83.7, 84.2 and 82.6, with a mean of 83.8. The estimated planetary A indices were 4, 3, 1, 1, 4, 2 and 3, with a mean of 2.6. The estimated mid-latitude A indices were 2, 3, 0, 3, 3, 2 and 2, with a mean of 2.1.

Until the past few days, the NOAA/USAF forecast showed solar flux dipping below 80 around now, something we have not seen since January 26-February 5, 11 days when the average sunspot number was 16.2. Note that the average sunspot number reported for the seven days through Wednesday, February 24 was 23, the previous seven days was 38.7 and 43.3 the week before that. The latest forecast (Thursday's, by the time this bulletin is written) shows solar flux at 82 for today, 80 over the weekend, 84 on March 1-4, 85 on March 5-6 and 90 on March 7-13. But the February 22 forecast showed solar flux below 80 beginning yesterday, February 25-March 2, going as low as 75 on March 1.

Solar flux is a rough proxy for sunspot numbers, and is measured with a parabolic dish antenna and a 2.8 GHz receiver tracking the Sun at the Dominion Radio Astrophysical Observatory (DARO) near Penticton, British Columbia -- about 168 miles (271 km) northeast of Seattle. You can see their daily solar flux data here. They report the flux values three times per day, but the noon reading at 2000 UTC becomes the official 10.7 cm solar flux reported for the day; it is shown in the "fluxobsflux" column. When we see it later from NOAA, the value is rounded off to the nearest whole number. For some reason, we find solar flux predictions, but no forecasts of sunspot numbers.

The latest NOAA/USAF forecast shows a small rise in geomagnetic activity, with planetary A index for February 26-March 5 of 5, 6, 7, 7, 7, 6, 5 and 5. Geophysical Institute Prague predicts quiet conditions for February 26-27, active for February 28-March 1, unsettled for March 2 and quiet for March 3-4.

We had many reports on 10 and 12 meter propagation over the past 10 days. Jon Jones, N0JK, of Wichita, Kansas reported working TX4T (Tahiti, or French Polynesia, same as FO prefix) on 28.49 MHz SSB with 100 W and a 20 foot high random length wire at 1932 UTC on February 15. The DX station was way over S9. Later he worked KH7Y on the east side of the Big Island of Hawaii, and then Brazil and Argentina. Jon notes that this Web site is a good source for info on the TX4T expedition. In a later e-mail, he noted that 10 meters was in great shape for the ARRL DX CW Contest, and he sent a sound clip of another contact with TX4T on 28.012 MHz CW at 2210 UTC on February 21. The sound clip has TX4T blasting through.

Ken Bourke, N6UN, operates a 10 meter beacon running 5 W in San Diego. He received his first reports in more than a year from Idaho and Louisiana this week, both reporting strong signals.

Another 10 meter report came from Charles Lewis, KY4P, who lives in the mountains of Western North Carolina. On February 21 during the contest from 2019-2034 UTC, he worked four New Zealand stations on 10 meter CW. They were all S9 and he got them on the first call. The only other DX station he could hear was an Argentine station.

Mike Meenan, ND6MM, is south of San Francisco and writes "I thought I'd have to wait a couple of years to be working Europe and Africa from here in 6-land with 100 W and a vertical, but I have been doing so consistently for the past two weeks on 15 meters between 1500-1700 UTC. The higher bands have really come alive, and the propagation has been pretty consistent, with some days better than others. I've even logged a couple of new countries (for me) including 7X4AN (Algeria) on CW and SV2CXI (Greece) on SSB. In the afternoon, beginning about 2100 UTC, there have been nice openings to the Pacific, which have yielded BX5AA (Taiwan) and 9M6BOB (Sabah, Borneo). Twelve and 10 meters have also had solid, though more sporadic, openings to the Caribbean and South America, and later in the day, the Pacific. I have been playing on Internet ham sites through the doldrums of winter, but it's still a thrill to work them on good old-fashioned HF!"

Dick Le Massena, W6KH (W7WVE when I was a kid and he was terrorizing the Pacific Northwest with his QRO hardware), in a recent online discussion characterized 1200 W as "QRP," and noted that last Saturday night (February 20), the conditions on 40 meters from 9:45-10:30 PM local time were "the best I have experienced in 56 years."

Brian Webb, KD6NRP, was surprised recently when he loaded a horizontal loop antenna that he uses on 40-6 meters on 160 meters. He fed just one side of his open wire line with a tuner and ran it against a counterpoise ground. He was pleased to work stations all over North America with 100 W. At 1345 UTC last Saturday (February 20), he heard TX4T on 1831 KHz with an S5 signal, but could not work him. Brian also reminds us of the NWRA site showing effective sunspot numbers here. These numbers are generated by combining actual ionospheric data from ionosondes with the 10.7 cm solar flux, rather than by counting sunspots. It is nice to see those numbers climbing.

I ran into a discussion on something called the Reverse Beacon Network, and was referred here. It uses the CW Skimmer technology to copy CW, and then puts the call sign and frequency information from multiple locations on the Web. There is also an article about this on page 22 of the March issue of WorldRadio that you can download free. Also check page 30 of the same issue for the K9LA propagation column.

Dick Bingham, W7WKR, who lives in a very remote area of Washington State, sent in a link to something he wants to use for putting up antennas next Field Day. The video is quite impressive, although it looks like a possible hazard at eye level. Dick wants to try this in place of a slingshot or archery to sling a line over a high tree branch.

Jack Luoma, W6JAK, of Gilroy, California, read about ham iPhone apps in last week's bulletin and mentioned that the open source Android OS for cell phones has Amateur Radio applications, too. Jack writes, "I have a Motorola Droid (with Android 2.1 OS) that has a neat little app called Tricorder that has options to display corona, UV, magnetogram and visible images of the sun with current sunspot number, flare and RF flux data. It also has the ability to measure (locally) acceleration, magnetic flux, sound pressure, RF (within wireless phone spectrum) and to display GPS satellite coordinates. The application interface emulates the Tricorder of Star Trek fame, including sound effects. There are other ham related apps available for Android phones that provide call sign lookup, propagation conditions and amateur satellite pass predictions. The number of applications being developed for the Android OS is increasing at a very fast rate."

Thanks Jack, and I love the high geek-factor of open source OS married to retro Star Trek technology! Just be careful and don't combine it with that transporter-thingy. The bugs were never worked out and it might be possible to materialize inside a solid object, which would be no fun at all.

Finally, I ran across this listing. Click on the QSL in the upper right to enlarge it. Note the blast resistant suit he is wearing while he stands next to a tactical robot. Now think about his vanity call sign.

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. 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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