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The K7RA Solar Update


Sunspot activity continued this week; new group 1035 emerged December 14, following group 1034 that appeared December 9. Daily sunspot numbers since December 9 through December 17 have been 13, 13, 13, 12, 14, 28, 38, 30 and 24. Solar flux values have been above 80 since December 15, with the values from Tuesday through Thursday of this week at 81.6, 83.2 and 86.9. The number at 2000 UTC (local noon in Penticton) is the official daily number, and on December 17 at 1800 UTC, the flux value was 88.1 -- higher than any flux value in the past three years. The last time the 10.7 cm flux was higher was December 15, 2006 at 88.2. Just three days prior to that on December 12, 2006, it was 104.2. It wasn't long ago that flux values were in the 60s, but we haven't seen solar flux below 70 since October 16, 2009, at 69.6.

Sunspot numbers for December 10 through 16 were 13, 13, 12, 14, 28, 38 and 30 with a mean of 21.1. The 10.7 cm flux was 73.9, 72.1, 74.5, 75.5, 78.6, 81.6 and 83.2 with a mean of 77.1. The estimated planetary A indices were 1, 0, 1, 2, 4, 0 and 3 with a mean of 1.6. The estimated mid-latitude A indices were 1, 0, 2, 1, 4, 0 and 2 with a mean of 1.4. The latest prediction from NOAA and USAF is for flux values around 88 for December 18-20, then 85, 82, 82 and 80 for December 21-25. The predicted planetary A index for December 18-24 is 5, 6, 15, 6, 5, 5 and 5, indicating a possible disturbance on Sunday. Geophysical Institute Prague predicts quiet conditions December 18-19, unsettled to active December 20, quiet to unsettled December 21-22, unsettled December 23 and quiet December 24.

Currently at the NASA STEREO site, we can see sunspot group 1035 at a high latitude heading toward the western (right-hand) side of the solar image, just passing over the eastern horizon a bright patch of activity that could emerge as a sunspot. There is also some activity in the southern hemisphere on the far side just emerging from the less than 13.7 percent of the Sun not visible to STEREO. If you go here, under the column "Sunspot Area 10E-6 Hemis," you can see the area (in millionths of a solar hemisphere) covered by sunspots steadily growing all week. This increased sunspot activity gives us improved chances of expanded HF propagation. For instance, doing a projection with a popular propagation prediction program, with 0 sunspots today from my location in Seattle to Brazil on 12 meters, there is a chance of propagation from 1800-2000 UTC, but for less than 25 percent of the time. But with an average of sunspot number for the past few days at 30.7, the same path has excellent probability of opening with strong signals from 1700-2100 UTC.

Mail after the ARRL 10 Meter Contest last weekend indicated that propagation was disappointing on Saturday -- and much better on Sunday. You can also see comments on the Contest Soapbox. Just select 2009 ARRL 10 Meter Contest from the drop-down menu.

In contrast to the 10 meter reports, there were a great many enthusiastic reports on 160 meters propagation this week. James French, W8ISS, of Lincoln Park, Michigan, operated from the Red Cross Communications Center in Ann Arbor. He reports that the 10 Meter Contest didn't get interesting until late in the event on Sunday, saying he "listened a few times down on 160 meters and heard non-stop signals across the whole band."

Jan Wise, KA5PRO, in Pocahontas, Arkansas, was surprised on December 10 at 0407 UTC when he contacted KH7XS in Laupahoehoe, located is on the northeast side of the Big Island of Hawaii. Jan was running 100 W SSB on 1.845 MHz into a simple inverted L antenna at 50 feet.

Dick Bingham, W7WKR, of Stehekin, Washington, reports that last Saturday night in the evening local (West Coast) time he was surprised to work an SM4HCM and FM5CD on 160 meter CW with 100 W into a sloping half-square antenna.

Jeff Hartley, N8II, of Shepherdstown, West Virginia, also reports great 160 conditions last weekend during the 10 Meter Contest. He noted great signals from Northern Europe, and 160 was "much better than during the 160 meter contest!"

Jon Jones, N0JK, of Wichita, Kansas, said 10 meters was bad Saturday, but he had great results on Sunday. He reports that "there was widespread E-skip across the southern part of the country. Had Texas, Louisiana, Mississippi, Florida and Alabama stations in all afternoon steady and loud. After 2200 UTC, the Es spread west to Arizona, New Mexico and northeast to Ontario, Maryland and Michigan. The Es to the Gulf of Mexico allowed an 'Es link' to form TEP (trans-equatorial propagation) and on to South America. So despite a low solar flux, CX, LU and PY stations were very strong around 2300 UTC December 13. I was able to work several PYs CXs and LU1HF while running 5 W and a CB mag-mount whip on the car on 10 meters CW. They were an honest 599, despite a very simple antenna to Kansas -- as strong as during the Solar Cycle 23 peak."

Randy Shirbroun, ND0C, of Worthington, Minnesota, reports some great 80 meter conditions last weekend. He wrote that he was "was playing around off and on in the 10 Meter Contest and there was some great Es and so-so TE on Saturday evening and especially Sunday afternoon. But for me, the really exciting thing was around midnight (local) on Friday night on 80 meters. I run exclusively QRP, so I am definitely a slave to the whims of the propagation gods. There wasn't anything going on 10 when I checked it around 0545 UTC Saturday -- not very surprising, but I was hoping for maybe a little MS (meteor scatter) or Es. So I went to 80 CW and was very pleasantly surprised. I was able to work 6 Central and Eastern Europeans (HA, HB, 9A, S5 and DK) in an hour, running 5 W to a dipole at 45 feet here in Southwestern Minnesota. It wasn't easy, but the band was relatively quiet with no big pile-ups and the guys on the other end were patient and obviously had good ears. It was definitely my best hour of 80 meter DXing! I think that was a very special opening, but I definitely need to check 80 more often (I'll bet it was a great night for the guys on 160 with decent antennas and a little power). Hopefully it is a sign of things to come this winter on the lower bands, especially with non-existent sunspots. Maybe 5BDXCC with QRP is possible! I have 240 on 10, 270 on 15, 270 on 20, 100 on 40 and now 55 on 80 - we'll see!"

Randy Crews, W7TJ, of Spokane, Washington, wrote on December 16 that "we are still in the low portion of the cycle, and I remember in years past during this time with a quiet Sun and geomagnetic field, low band propagation is exceptionally good. The higher solar activity enhances 40 meters, 30 meters and even 80 meters. Last weekend, I worked three new European countries on 160 meters. Eighty, 40, and 30 meters offer short path European propagation starting an hour before local sunrise, switching to long path at sunrise and back to short path propagation once again about 45 minutes to an hour past sunrise. Pretty cool!"

Robert Elek, W3HKK, of Johnstown, Ohio, reported on December 12, "Hark! Sunspots! And a big bump up in 40/80/160 DX was noted on December 11 and 12. But prior to that, 40 had been relatively quiet for the past week; however, on 12 and 6 meters, OX3KQ sounded like a beacon on 7.153, with signals from S7 to S9 +5 dB for a couple of hours (1900-2100 UTC) -- mid afternoon! My average noise level was S2. OX3KQ was using a rotary dipole at 70 feet and working pile ups into most of Europe, plus pockets of JA and stateside stations who could penetrate his European wall. HA, IZ4, EC, UW5, DJ2, YO, RK0, A41, Z31, UR5 and RZ8 were a sample of what he was plucking off, plus a dozen or so US and a dozen JAs. Non stop DX for him, and it sounded like he was picking them off the top of the pile. Fascinating to see how the skip would move around favoring first to his east, then to his west, then to his north. Again, we see that on a quiet or dead band, DX is possible from almost any point on the globe on 40 meters. Also, E51NAA (the North Cook Islands) was worked again, on both Dec ember 11 and 12, between 0400-0500 UTC, around 7.025 MHz with good signals. I've heard him coming through for over a week now, again, on a quiet band. Another magical opening on 160 -- on December 11 at 0500 UTC, I worked TF4M, plus LA, SM and PA, all with 599 signals, with 100 W CW/160 meters inverted L with an average height above ground of 10 feet! It seems 1.815-1.840 MHz is a jam packed DX segment, especially on Friday and Saturday nights. And around 1.843, a UM0 (Uzbekistan) was a solid 5×7(3 S-units above my noise) and looking hard for takers. Amazing! You could hear nearly all of Europe calling CQ that night, many signals in the 579 to 599 range. On an antenna you could almost jump up and touch! Amazing. So it doesn't take a lot to join the fun."

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.



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