[DX-NEWS] ARLP029 Propagation de K7RA
SB PROP @ ARL $ARLP029 ARLP029 Propagation de K7RA ZCZC AP30 QST de W1AW Propagation Forecast Bulletin 29 ARLP029 From Tad Cook, K7RA Seattle, WA July 20, 2012 To all radio amateurs SB PROP ARL ARLP029 ARLP029 Propagation de K7RA In last week's bulletin ARLP028 we reported a blast of energy from a solar flare headed our way, predicted arrival on Saturday, July 14. The CME hit at 1800 UTC, and had a huge effect on propagation and geomagnetic indices. The next day the planetary A index was 60, mid latitude A index was 39, and the high latitude college A index was 88. Conditions haven't been that upset since March 9, 2012, when the mid-latitude A index was 57, planetary A index was 67, and the college A index was 107. All other indices were lower, with the weekly average of daily sunspot numbers down over 16 points to 104.7, and average of daily solar flux down 25 points to 141.8. The latest prediction from NOAA/USAF has solar flux at 95 on July 20-21, 100 on July 22, 105 on July 23-24, 110 on July 25-27 then 165 on July 28 through August 2, 160 on August 3-4, and 165 on August 5. Predicted planetary A index is 5 on July 20-21, then 12 and 8 on July 22-23, 5 on July 24-27, 20 on July 28-29, 10 on July 30-31, 15 on August 1-2, 10 on August 3-4, 8 on August 5, and 5 on August 6-22. OK1HH predicts quiet to unsettled conditions July 20, quiet July 21, quiet to active July 22, mostly quiet July 23-24, quiet July 25, quiet to active July 26, active July 27-28, mostly quiet July 29, quiet on July 30, quiet to active July 31 through August 2, quiet August 3, mostly quiet August 4, active August 5, mostly quiet August 6-7, quiet to unsettled August 8, quiet August 9, quiet to unsettled August 10, and active on August 11. How well do the forecasts from NOAA/USAF (at http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html) do in predicting what will happen next week, or a few weeks out? No statistics here, but I noticed that the current solar flux depression (with flux values at 100 of less for the next few days) has been predicted for weeks. Solar flux values for July 16-19 show the trend, with values of 154.4, 127.5, 109.5, and 100, and now on Thursday July 19 the predicted values for July 20-22 are 95, 95 and 100. Looking back at the forecast from July 2, we see the same dip around this time of the month, only longer and deeper. That date it showed flux values on July 18-23 at 100, 90, 85, 85, 90 and 100. On July 9 this was revised, and the dip was only down to 105, centered on July 20-21. On July 13 this was adjusted down, with the minimum at 100, on July 18-20. Revised again on July 14, it now had the flux at 100 on July 19-21. The July 15 forecast shifted it again, at 100 on July 20-23. On July 16 it changed again, with flux values of 105, 95, 95, 95, 95 and 130 on July 19-24. On July 17 the July 24 value changed from 130 to 105, and on July 18 the minimum went from 100, 95, 95, 95 and 100 on July 19-23, and now on July 19 it is 95, 95 and 100 on July 20-22. So over the past few weeks the forecast for a short term minimum has shifted around the next few days, and we hope it becomes more accurate as we close in on the date. Dave Greer, N4KZ of Frankfort, Kentucky wrote: Here it is some 24 hours after total bedlam - a good kind of bedlam - on 6 meters on Monday, July 16. From the DX Sherlock website, I knew before I left work that 6 would be on fire by the time I got home from work. It did not disappoint. In fact, it threw me an unexpected surprise. I got on at 2118 UTC and didn't leave the rig for the next three hours as the Caribbean and northern South America boomed into my EM78ne QTH in Frankfort, KY. I worked some 20 stations. None represented new 6 meter DX entities for me but it was still a blast. You don't work Brazil on 6 meters every day, at least I don't. But in the midst of the chaos, I heard W3GMT calling CQ with a strong signal and no takers. I felt sorry for him and answered his next CQ. I nearly fell out of my chair when he said his QTH was Charleston, South Carolina. You see, South Carolina was the LAST state I needed for 6 meter WAS. And it only took me 25-plus years to work it. South Carolina is practically in my backyard. That's the problem - it's too close. If I had worked at it, I could have worked it years ago but I preferred the casual approach. So 12 years after I worked Alaska on 6 meters, 10 years after I worked Hawaii, I finally got my last state. That I didn't expect when I turned on the rig on July 16. By the way, I just put up a new 6 meter Yagi on my tower on Saturday so this was the perfect way to break it in. Compared to the big guns on 6 meters - with the KW amps and Yagis with booms that are longer than my tower is tall - I'm just a peanut whistle but with my 100 watts and modest Yagis over the past years I have managed to work 70 countries on 6 meters, all continents and now all 50 states. And yes, it is still and will
[DX-NEWS] ARLP029 Propagation de K7RA
SB PROP @ ARL $ARLP029 ARLP029 Propagation de K7RA ZCZC AP29 QST de W1AW Propagation Forecast Bulletin 29 ARLP029 From Tad Cook, K7RA Seattle, WA July 22, 2011 To all radio amateurs SB PROP ARL ARLP029 ARLP029 Propagation de K7RA Average daily sunspot numbers for the week rose nearly 27 points to 92.4, while average daily solar flux increased over 9 points to 98.2. The latest prediction has solar flux values for the next week a little lower than those listed in Thursday's ARRL Letter. Expected values are 96 for today, July 22, then 95 on July 23-27, 98 on July 28, 90 on July 29 through August 2, 95 on August 3-7, 98 on August 8, and back to 100 on August 9-16. Planetary A index for July 22-23 is predicted at 10 and 8, then 5 on July 24-28, 8 on July 29-31, then 10, 8, 5 and 8 on August 1-4, 12 on August 5-7, and 8 on August 8-10. Geophysical Institute Prague has a weekly prediction for geomagnetic indices that doesn't use the A or K index, but instead has seven levels of activity, from quiet to severe storm. Their prediction for this week says to expect unsettled conditions for today, July 22, quiet to unsettled on July 23, quiet July 24-25, quiet to unsettled July 26-27, and quiet again on July 28. There seem to be plenty of sunspots visible over the past week, but nothing really large or very active. Sunspot areas are counted in millionths of a solar hemisphere, and on Thursday, July 14, there were six sunspot groups visible: 1245, 1250, 1251, 1252, 1254 and 1255. The area ranged from 5 for sunspot group 1245 to 100 each for groups 1250 and 1251. Total sunspot area for that day was 265. On Friday, July 15, a new sunspot group 1256 was added, and total sunspot area was 260, as the other sunspot groups shrank, except for 1251 and 1254. On July 16, 1255 disappeared, and total sunspot area dropped to 230. On Sunday, July 17, sunspot areas 1245 and 1252 disappeared, new group 1257 was added, and total sunspot area grew to 280. On Monday, July 18 sunspot area jumped to 400 when two new groups, 1258 and 1259 were added. On July 19 sunspot area jumped again to 660, when 1255 disappeared and all sunspot groups except 1256 grew. 1250, 1257 and 1258 each doubled in size, while 1259 more than tripled. On July 20, 1256 and 1257 disappeared, and sunspot area dropped by more than half to 310. Yesterday, July 21, 1250 and 1258 went away, and sunspot area declined from 310 to 290, and daily sunspot number declined from 79 to 56. There has been quite a bit of news about a predicted grand minima in solar activity. We recently reported on a conference in which three lines of evidence were presented which seemed to point to a future disappearance of sunspots, perhaps like the dreaded Maunder Minimum. I am not unbiased in this regard, and like most amateur radio operators yearn for high solar activity. Alas, a return of cycle 19, the granddaddy of them all, seems elusive. But there is some dissent regarding these predictions of no sunspots, which gives us hope. On Wednesday I spoke with Dr. Douglas Biesecker, an astrophysicist at the NOAA Space Environment Center in Boulder. He was mentioned in ARLP024 (see http://www.arrl.org/w1aw-bulletins-archive/ARLP024/2011) as dissenting from the assertion that evidence points toward sunspots disappearing or another Maunder Minimum in our future. He mentioned something called a Gleissberg Cycle. What happens when we do a really long smoothing of sunspot numbers? The smoothed sunspot numbers we are familiar with, the data used in those nice graphs of sunspot cycles, average data over 13 months. So every place you look on the graph doesn't show the variation that occurred during that month, but instead averages data over more than a year, to smooth out all the noise of daily variations. But what would happen if you smoothed the numbers over a much longer period, say 11 years? Could you find some periodicity that would suggest a cycle of cycles, or perhaps predict clusters of decades with low or high solar activity? Gleissberg cycles suggest a periodicity of about 87 years, and some have studied these to try to predict general levels of solar activity over multiple decades. But if a cycle is 87 years long, and we only have about 256 years of directly observed solar data, the most we could look at would be less than three cycles. That isn't enough data to make even crude speculative projections. Doug mentioned what he referred to as an old NASA axiom, that goes something like this: If you can't see something happen seven times, it isn't real. Doug said he is attending SHINE workshops, and SHINE is an acronym for Solar Heliospheric and Interplanetary Environment (see http://shinecon.org/). At these meetings participants have been hashing out the evidence for or against a no cycle 25 scenario, and discovering some problems with the three lines of evidence pointing toward a disappearance of sunspots. They haven't reached a
[DX-NEWS] ARLP029 Propagation de K7RA
SB PROP @ ARL $ARLP029 ARLP029 Propagation de K7RA ZCZC AP29 QST de W1AW Propagation Forecast Bulletin 29 ARLP029 From Tad Cook, K7RA Seattle, WA July 23, 2010 To all radio amateurs SB PROP ARL ARLP029 ARLP029 Propagation de K7RA Sunspot activity increased recently, although it is foolish to call this a trend because solar activity has great variability. Sunspot group 1087 was visible for 13 days over July 9-21. In millionths of a solar hemisphere, its size was 30, 100, 120, 130, 70, 100, 60, 50, 20, 10, 10, 10, and 10. On July 19 new sunspot group 1089 appeared over the eastern horizon, with a relative size of 130, 150, 310 and 240 for July 19-22. Predicted solar flux for July 23-25 is 88, 85 on July 26-30, and 83 on July 31. This is fairly strong, considering that the average daily solar flux for each of the past four weeks was 73.9, 72.8, 79.2 and 80.6. There is a small predicted rise in geomagnetic activity, with a predicted planetary A index from July 23-31 of 10, 10, 8, 8, 10, 7, 7, 5 and 5. Geophysical Institute Prague predicts unsettled conditions on July 23, quiet to unsettled July 24, unsettled July 25-26, unsettled to active July 27, and unsettled July 28-29. Perhaps another sign of a quiet sun, which includes a weakening solar wind, is the collapse of the Earth's thermosphere. Marcia Stockton, NU6N, who lives off the grid on a wilderness ranch northeast of Bakersfield, California at elevation 4,500 feet, shared with us an interesting article from NASA. Titled A Puzzling Collapse of Earth's Upper Atmosphere, you can read it at http://tinyurl.com/26mo68u. Kurt Kochendarfer, KE7KUS of Phoenix, Arizona sent in a report last week just a few hours late for bulletin ARLP028. He reports, The evenings of 11 and 12 July I was working 20m PSK-31 around 14.070 and saw strong openings into central European Russia from my QTH in Phoenix, AZ which began around 0330Z and lasted approximately an hour on each night. With a minimal antenna setup (275 foot long horizontal loop mounted on top a block fence up about 6 feet) and 50W I worked UR8MH, UA3PT, RZ3DC, and RA3FO in a period of 20 minutes beginning at 0340Z on 11 July. Numerous other Russian and Ukrainian stations were heard, but I was unsuccessful breaking through the mini-pileups. This was a real treat, as I usually have a hard time working that far east in Europe with my antenna setup. I suspect the gray-line may have had something to do with the propagation, and it made for an enjoyable couple of hours to add some new European DX to the logbook. Summer evening DX on 20m has been relatively good here in Phoenix, of late as well. In the last month I've had success working FO8RZ in Tahiti, and heard a number of South Pacific stations from New Caledonia all the way to central Australia. While the solar numbers aren't anything remarkable, the relatively quiet conditions combined with my loop antenna have made for lots of new contacts in the logbook. Thanks, Kurt. That low antenna sounds like a good NVIS aerial for 75-80 meters. NVIS, for those who don't know, stands for Near Vertical Incidence Skywave. The concept involves an antenna close to the ground with a high angle of radiation. That is supposed to provide better regional coverage on the low bands than a low-angle radiator does because the radiation going up refracts back to a more immediate area. Assuming that 1005 divided by MHz is a good formula for calculating dimensions of a full-wave loop, then the reciprocal suggests a frequency of 3.655 MHz. Mike Majority, N4VBV of Sumter, South Carolina mentions that beacons on the ten meter band are useful for detecting openings, even when no live hams are on the air. His QRZ.com page at http://www.qrz.com/db/n4vbv gives some beacon info and resources, and he suggests W5JO as a good source of data. W5JO has a beacon list for 10 meters at http://www.qsl.net/wj5o/bcn.htm. It is also worth mentioning the Northern California DX Foundation and their sophisticated networks of beacons on 20, 17, 15, 12 and 10 meters. See info on their web site at http://www.ncdxf.org/beacon/intro.html. Jim Fenstermaker, K9JF lives in the Ballard neighborhood in Seattle, but has a station in Vancouver, Washington (not to be confused with the VE7 Vancouver) near Portland, Oregon. He writes, The opening on 20 on Saturday evening and Sunday morning was fantastic during the IARU Contest, the best I have seen for many years. By Z on Saturday, I worked one (1) WRTC station and in the evening I was able to add another 37 or so. Overall, my low power entry totaled 953 Q's. I operated from the Vancouver QTH which allowed for the antennas to play and the neighbors to be spared from large amounts of RF in their stereos. But, all the locals worked stations over me as they were high power entries. I now have the view that both QRP and Low Power is not for sissies. And, I have not sat in the chair for 24 straight hours for years either. Robert
[DX-NEWS] ARLP029 Propagation de K7RA
SB PROP @ ARL $ARLP029 ARLP029 Propagation de K7RA ZCZC AP29 QST de W1AW Propagation Forecast Bulletin 29 ARLP029 From Tad Cook, K7RA Seattle, WA July 11, 2008 To all radio amateurs SB PROP ARL ARLP029 ARLP029 Propagation de K7RA Another week, and still no sunspots. The three month moving average for daily sunspot numbers that we began reporting toward the end of cycle 23 seemed to suggest retrospectively that solar minimum occurred last fall. The daily average for the three month period centered on last October was nearly 3, or 2.967 to split some hairs. This is an average of the 91 daily sunspot numbers from September 1 through November 30. Following that low, November was 6.85, and between December 2007 through April 2008 the 3-month average drifted from 8.14 to 8.89. With remaining cycle 23 spots becoming increasingly rare, and barely any cycle 24 spots, this suggested solar activity was stalling out. Then at the end of June, a further decline, when the 3-month average centered on May dropped to 5.04. Randy Crews, W7TJ of Spokane, Washington has an interesting observation regarding a possible double-minimum between cycles. He was looking at some charts of past sunspot cycles in W3ZZ's World Above 50 MHz column on page 90-91 in the February 2008 issue of QST. Randy wrote, ''I noted the average period from a cycle's peak declining to its low is on average 7 years. So, linking that to our current cycle's progress, things get interesting: If you count from the 1st cycle 23 peak (April or July of 2000) we are at the 8 year mark now and past due. However, cycle 23 had a second peak November/December of 2001. We have not yet reached the 7 year mark if you count from peak #2 and that would coincide perfectly with Ken's article. Interesting enough, the NOAA propagation charts predict this fall as being the real pickup''. When Randy mentions ''Ken's article'', he is referring to Dr. Kenneth Tapping of the Dominion Radio Astrophysical Observatory in Penticton, British Columbia, the source of our daily 10.7 cm solar flux numbers. Following a widely circulated false quote attributed to Tapping, we made available his notes on the cycle minimum to anyone who sends a blank email to [EMAIL PROTECTED] That offer still stands, and to date over 1,100 copies have been dispatched to readers who sent an email to that address. Randy also mentions ''NOAA propagation charts'', but I suspect he means tables of predicted smoothed sunspot numbers. Those can be found at http://www.swpc.noaa.gov/ftpdir/weekly/Predict.txt and on page 8 at http://www.swpc.noaa.gov/weekly/pdf/prf1714.pdf. So what do zero sunspots mean for HF propagation in mid-July? From my home in Seattle, the path to Japan has a Maximum Usable Frequency that varies from a low of 13.1 MHz at 1630z to a maximum of 16.8 MHz at 0530z. To Hawaii, the lowest MUF is 11.3 MHz at 1200z to highest of 17.2 MHz at 0500z. A further example is Texas to Brazil, with MUF ranging from 6.4 MHz at 0900z to 20.8 MHz at 0200z. That is all a very narrow range. With an average sunspot number of 100 for that Texas to Brazil path, low of 18.2 MHz at 0900z to 29.7 MHz at 1730z and 2100z, enough to support good 10 meter propagation. Sporadic-e propagation on 10 and 6 meters generated more mail this week. Jeff Hartley, N8II of Shepherdstown, West Virginia sent the following report on July 4. ''Just a quick note to mention the 6M condx on June 27-28. Around 2000Z on the 27th the Es opening began on 50 MHz here. ''I had very bad luck getting any Europeans to answer my CQ and my Euro footprint was pretty small to northern F, PA, southern G, and EI. I worked a total of about 6 stations in the mentioned countries. There were a few weak signals persisting past 2200Z (heard MM0AMW). ''Most all of the activity was on CW, long live CW! ''Saturday morning, June 28, I turned on the radio to find loud Italians all over the 50.080-50.100 segment at 1320Z. I worked quite a few in the I-4 call areas. There was a loud IZ1 who couldn't hear 3/4 of the stations calling him and I heard a weak I7. ''I worked a total of about 15 stations over 45 minutes or so and again there was surprisingly much more activity on CW than phone. This time, I did get a few CQs answered. Also heard were S57RR, 9A1CCY, and a 9A6, but the pile-ups were big and unruly on the first 2 guys. K1HTV near DC missed the S5 due to two callers out of turn. I would have persisted, and not let the ''breakers'' in if I were the DX''. Joaquin Montoya, EA2CCG says on June 30 there was a nice 10 meter opening to the Caribbean with Martinique booming in, and Ecuador also. July 2 had him working his first 6 meter sporadic E skip, with a dozen European stations out to about 1500km. They were all from Poland, Denmark and Germany. Russ Hunt, WQ3X on Kitner Hill in Upper Black Eddy, Pennsylvania mentioned on July 6 that there were great 6 and 10 meter openings on June 27-28. He wrote: ''On 6-27 I worked the
[DX-NEWS] ARLP029 Propagation de K7RA
SB PROP @ ARL $ARLP029 ARLP029 Propagation de K7RA ZCZC AP29 QST de W1AW Propagation Forecast Bulletin 29 ARLP029 From Tad Cook, K7RA Seattle, WA July 13, 2007 To all radio amateurs SB PROP ARL ARLP029 ARLP029 Propagation de K7RA The average of daily sunspot numbers for this reporting week, July 5-11, were about the same as the previous seven days, declining slightly by less than two points. We've seen no zero sunspot days since an eleven-day spotless period ended on June 25. If sunspot numbers continue at this level and higher, it will become easier to convince ourselves that the sunspot minimum is already behind us (see the table of 3-month moving averages in last week's bulletin ARLP028 at http://www.arrl.org/w1aw/prop/2007-arlp028.html). On July 11 the Air Force had a prediction for heightened solar flux (probably indicating more sunspots) from July 13-15 (see http://tinyurl.com/yonktp). Alas, by Thursday afternoon the predicted solar flux had dropped ten points (see http://tinyurl.com/2ffq9n) from 85 to 75 for the same period. Using some very rough approximations plus maybe a fudge-factor or two, this might be reflected in a slightly greater than thirteen point difference in the expected daily sunspot number. Predicted planetary A index for July 13-19 is 8, 10, 8, 8, 8, 15 and 20. For the same period Geophysical Institute Prague predicts quiet to unsettled conditions for July 13, unsettled July 14, quiet July 15-17, and unsettled July 18-19. Wade Grimes, K0MHP of Elsberry, Missouri wrote to ask if six meters is the ''magic band, or invisible band?'' He isn't hearing the propagation on six reported in this bulletin. He's having much better luck on 20 meters, although he is constructing a quad antenna for six, and he does copy some distant beacon signals. I should point out that not everyone is hearing DX on six, but still the reports come in from those who are patient and lucky. Ken Tata, K1KT sent in more examples via maps generated at vhfdx.net . Poke around this site, and you will find both current real-time maps showing propagation on 2 and 6 meters for both North America and Europe, and some fine examples of recent propagation on some archived maps. Howard Runyons, W4HLR of Newbern, Tennessee (EM56jb) wrote about he and N4QWZ (EM66) both working W7CI (DM41) in Sierra Vista, Arizona on 2 meters on June 27 at 2349z. Howard ran 50 watts through hard-line to a 15 element beam at 40 feet. Mark Roberts, KD5SMF of Fairview, Oklahoma has been enjoying both 6 and 10 meters, and he recently took a trip up Gloss Mountain (EM06xj) to see what he could work on both bands. At over 1500 feet on July 7, he worked 41 stations on 10 meters, nearly all to the southeast and northeast. He worked one station in Anaheim, California. As the propagation moved, he got many reports of 10 db over S9, but after moving west, propagation shut down. You can see a photo of him and his portable operation at http://www.qrz.com/kd5smf. Thanks to David Sumner, K1ZZ of Coventry, Connecticut, who pointed out that in last week's bulletin the call sign for John Butrovich is W5UWB, not W6UWB. If you would like to make a comment or have a tip for our readers, email the author at, [EMAIL PROTECTED] For more information concerning radio propagation, see the ARRL Technical Information Service at http://www.arrl.org/tis/info/propagation.html. For a detailed explanation of the numbers used in this bulletin, see http://www.arrl.org/tis/info/k9la-prop.html. An archive of past propagation bulletins is at http://www.arrl.org/w1aw/prop/ . Monthly propagation charts between four USA regions and twelve overseas locations are at http://www.arrl.org/qst/propcharts/. Sunspot numbers for June 5 through 11 were 24, 12, 23, 16, 20, 25 and 28 with a mean of 21.1. 10.7 cm flux was 71.5, 71.1, 73.1, 75.1, 77.1, 78.1, and 78.5, with a mean of 74.9. Estimated planetary A indices were 5, 5, 6, 4, 3, 6 and 23 with a mean of 7.4. Estimated mid-latitude A indices were 3, 4, 4, 3, 2, 5 and 14, with a mean of 5. /EX -- Archives http://www.mail-archive.com/dx-news@njdxa.org THE DXR is sponsored by the North Jersey DX Association. Please visit our website: http://www.njdxa.org/index.php scroll to bottom for subscribe/unsubscribe options --
[DX-NEWS] ARLP029 Propagation de K7RA
SB PROP @ ARL $ARLP029 ARLP029 Propagation de K7RA ZCZC AP29 QST de W1AW Propagation Forecast Bulletin 29 ARLP029 From Tad Cook, K7RA Seattle, WA July 21, 2006 To all radio amateurs SB PROP ARL ARLP029 ARLP029 Propagation de K7RA Solar activity remains low, and was lower this week than the week before. Average daily sunspot numbers dropped over six points to 19.4, and solar flux was down over five points to 70.7. July 13 saw the solar flux dip just barely below 70 to 69.9. During extended periods with zero sunspots, we will see solar flux around 67 or 68. I believe the solar flux hasn't been below 70 in almost exactly nine years, back to July 17, 1997 when it was also 69.9. Today the sun appears spotless, although the sunspot number is above zero. Expect continued low levels of solar activity. For the next few days expect solar flux around 70, rising to 75 after Sunday, July 23. This is not a big change. It is roughly equivalent to the sunspot number rising from 11 to 18. This doesn't mean that solar flux and sunspot numbers are completely independent. This week we saw average solar flux around 71 and average sunspot number around 19. Five years ago with an average solar flux around 141, average daily sunspot numbers were around 162. Geomagnetic indices should be quiet, with a planetary A index of five. The next period of higher geomagnetic activity due to recurring coronal holes rotating into view is some moderate activity expected around Tuesday, July 25, and then some higher activity centered on August 1. This is a prediction from the U.S. Air Force Space Weather Operations. Geophysical Institute Prague predicts quiet conditions for July 21-24, unsettled conditions July 25-26, and quiet to unsettled July 27. Check this article on Space Weather from The Industrial Physicist: http://www.aip.org/tip/INPHFA/vol-9/iss-6/p18.html. Note the nice illustration of magnetic and solar convection patterns about half way down the page. If you would like to make a comment or have a tip for our readers, email the author at, [EMAIL PROTECTED] For more information concerning radio propagation, see the ARRL Technical Information Service at http://www.arrl.org/tis/info/propagation.html. For a detailed explanation of the numbers used in this bulletin, see http://www.arrl.org/tis/info/k9la-prop.html. An archive of past propagation bulletins is at http://www.arrl.org/w1aw/prop/ . Sunspot numbers for July 13 through 19 were 11, 15, 17, 20, 23, 26 and 24 with a mean of 19.4. 10.7 cm flux was 69.9, 70.9, 70.2, 70.8, 71, 71.2, and 71.1, with a mean of 70.7. Estimated planetary A indices were 5, 14, 6, 4, 4, 3 and 2 with a mean of 5.4. Estimated mid-latitude A indices were 3, 10, 5, 2, 2, 2 and 2, with a mean of 3.7. /EX -- Archives http://www.mail-archive.com/dx-news@njdxa.org THE DXR is sponsored by the North Jersey DX Association. Please visit our website: http://www.njdxa.org/index.php scroll to bottom for subscribe/unsubscribe options --
[DX-NEWS] ARLP029 Propagation de K7RA
SB PROP @ ARL $ARLP029 ARLP029 Propagation de K7RA ZCZC AP29 QST de W1AW Propagation Forecast Bulletin 29 ARLP029 From Tad Cook, K7RA Seattle, WA July 15, 2005 To all radio amateurs SB PROP ARL ARLP029 ARLP029 Propagation de K7RA The big patch of sunspots that energized activity less than two weeks ago has drifted around the edge of the Sun. You can see the effects in the falling daily sunspot numbers and solar flux. Average daily sunspot number dropped a little over 63 points to 91.3. At the same time, geomagnetic disturbance increased, so ideal conditions with high sunspot activity and quiet geomagnetic conditions are reversing. On July 10 a coronal mass ejection from a day earlier hit Earth, and caused a geomagnetic storm. The same day it hit, the planetary A index jumped to 47, and another coronal mass ejection began a journey from the sun. As a result, the planetary A index went back up, this time to 48 on July 12. All this as sunspot numbers and solar flux dropped. Solar activity is currently increasing, but only from some sunspots that are drifting from view. They may deliver an indirect hit to Earth in the next couple of days. The interplanetary magnetic field, or IMF, is pointing south, which means our Earth is vulnerable. Currently the planetary A index for Friday through Monday, July 15-18 is predicted to be 25, 25, 20 and 12. Sunspot numbers and solar flux should reach a short term minimum around July 16-19, and another maximum around August 2-5. This is based on the recent peak in activity, and the fact that the sun rotates relative to earth about once every 27-28 days. This time of year West Coast stations often see good propagation in the evening to the west and southwest, to Hawaii, and down toward Australia, where the season is now winter. 20 meters can be open all night, with 15 and 17 meters showing good propagation through the evening. The East Coast of North America will see good 20 meter propagation into the evening toward Europe, with the band often staying open four or five hours later than it will about a month from now. If you would like to comment or have a tip, email the author at, [EMAIL PROTECTED] For more information concerning radio propagation and an explanation of the numbers used in this bulletin see the ARRL Technical Information Service propagation page at, http://www.arrl.org/tis/info/propagation.html. An archive of past bulletins is found at, http://www.arrl.org/w1aw/prop/. Sunspot numbers for July 7 through 13 were 149, 111, 126, 78, 68, 52 and 55 with a mean of 91.3. 10.7 cm flux was 124.9, 110.4, 106.6, 101.8, 93.3, 95.3 and 91.7, with a mean of 103.4. Estimated planetary A indices were 8, 5, 19, 47, 23, 48 and 30 with a mean of 25.7. Estimated mid-latitude A indices were 6, 5, 13, 28, 14, 17 and 20, with a mean of 14.7. /EX -- Archives http://www.mail-archive.com/dx-news@njdxa.org THE DXR is sponsored by the North Jersey DX Association. Please visit our website: http://www.njdxa.org/index.php scroll to bottom for subscribe/unsubscribe options --
