[DX-NEWS] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA February 3, 2012 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA Here are some yearly averages this bulletin neglected at the beginning of the year. These are the average daily sunspot numbers for whole calendar years, from 1994-2011: 48.1, 28.7, 13.2, 30.7, 88.7, 136.3, 173, 170.3, 176.7, 109.2, 68.6, 48.9, 26.1, 12.8, 4.7, 5.1, 25.5, and 29.9. You can see from these numbers that the minimum between Cycles 22-23 centered around 1996 was over quickly. But the next minimum before Cycle 24 centered around 2008-2009 was much longer. In 2011 we were back near the levels we saw in 2006, 1997 and 1995. Also note that from 2009-2010 the average daily sunspot number increased by 400% (multiplied five times), but from 2010-2011 it moved up only 17.3%. The 3-month moving averages of daily sunspot numbers, centered on January through December 2011 are: 35.3, 55.7, 72.3, 74.4, 65.9, 61.5, 63, 79.6, 98.6, 118.8, 118.6 and 110. The value centered on December 2011 is the average of the daily sunspot numbers from November 1, 2011 through January 31, 2012, and the value centered on November 2011 includes all daily sunspot numbers from October 1, 2011 through December 31, 2011. Over the past reporting week - January 26 through February 1 - the average daily sunspot number declined nearly 37 points to 62. Average daily solar flux was off nearly 21 points to 120.4. On February 2 the sunspot number and total area of sunspot regions was the same as February 1. The noon flux measurement moved from 117.5 to 118 from February 1-2. Predicted solar flux for the near term is 120 on February 2-5, 110 on February 6-9, 150 on February 10, 155 on February 11-13, 150 on February 14-19, and 145 on February 20-23. The forecast in mid-January for flux levels at 165 on February 17-21 are but a distant memory. Unfortunately, for some reason predictions updated for Thursday were not yet available early Friday, February 3, so the numbers in the previous paragraph were not updated since Wednesday, February 1. But you can still get the latest prediction from http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html. The 20 point difference in predicted solar flux should be a noticeable difference. Although this is not an accurate prediction method, for comparative purposes I ran a W6ELprop forecast for February 19 from the center of the USA to Hungary with a solar flux of 145, and then again at 165. On the higher frequencies in particular, paths would not be as reliable nor openings as long as with the higher value. There is a new updated NASA prediction for the peak of the current cycle issued early this morning. The previous update was on January 3. There is no archive of past predictions online, but I can tell you that the prediction for the peak of Cycle 24 is still for a smoothed international sunspot number of 96, but it has moved from February 2013 to late 2013. NASA gives a detailed explanation of the models they use for predicting the peak of the cycle, and you can read it all at http://solarscience.msfc.nasa.gov/predict.shtml. Also see the graph at http://solarscience.msfc.nasa.gov/images/f107_predict.pdf for a revised solar flux prediction. Shortly after the last bulletin was released last Friday, January 27, at 1837 UTC a powerful X-class solar flare was released, but not Earth-directed. In case you missed it last week, Science Friday on NPR ran a fascinating story on space weather, and they spoke with astronomer David Hathaway of NASA and astrophysicist Doug Biesecker of NOAA. You can hear the broadcast from an archive at http://www.npr.org/2012/01/27/145990089/how-space-weather-affects-planes-and-power-grids. They mention ham radio and effects on shortwave radio propagation, and Biesecker gives a fascinating account of Carrington's observation of a solar flare and how it caused the great magnetic storm of September 2, 1859, in which aurora was observed worldwide. An Alaska news site ran a story on photography of aurora. Read it at http://www.alaskadispatch.com/article/how-photograph-northern-lights. There were two similar articles on the formation of sunspots this week. One was at http://www.universetoday.com/93188/cool-gas-may-be-at-the-root-of-sunspots/, the other: http://www.space.com/14423-sunspots-sun-mystery-magnetic-theory.html. We received a nice note from Ed Richmond, W4YO of Harbor Island, South Carolina (EM92): The evening of Friday, January 27 into the 28th was extraordinary here. At about 0145z I came into the shack to take a last check on band activity before hitting the big switch, checked the DX cluster for activity on 6 meters and saw a whole lot of TEP activity. I turned on my rig and immediately heard ZP6CW calling CQ, weakly. I called him with no luck. Tuning around, I heard a bunch of PYs and LUs. Wow! My first experience
[DX-NEWS] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA February 4, 2011 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA The past week had one zero sunspot day, Thursday, January 27. Activity came right back, but the average daily sunspot number for the week fell over 12 points to 20.1, and average daily solar flux declined 2.7 points to 80.8. After the sunspot numbers of 21, 22 and 22 on Monday, Tuesday and Wednesday, the sunspot number rose to 32 on Thursday, February 3. Predicted solar flux values for the next week were below the average for the previous seven days when reported on Thursday in the ARRL Letter, but the forecast has improved since then. Solar flux values forecast by NOAA/USAF are 80 on February 4-8, 78 on February 9-10, then 80, 80, 82, 81, 81, 82 and 88 on February 11-17. Predicted A index on February 4-5 is 10 and 8, followed by 5 on February 6-28. Geophysical Institute Prague sees unsettled to active conditions for today, February 4, unsettled February 5, quiet on February 6-8, quiet to unsettled February 9, and unsettled conditions return on February 10. On Friday the STEREO craft are now very, very close to perfect alignment for 100% coverage of the Sun. I checked just now at 1430 UTC on February 4, and STEREO has achieved 99.899% coverage, the missing sector now a tiny slit near the 180 degree meridian. See it at http://stereo.gsfc.nasa.gov. By 2300 UTC on February 5 STEREO coverage should be 99.917%, and it should reach 100% coverage shortly after 0926 UTC on Sunday, February 6. This is when the STEREO satellites begin their move into the position where the gap closes on our Sun's far side, and begins to open on the Earth side. Images from the NASA Solar Dynamics Observatory will begin to fill the new gap along the Sun's zero degree meridian, the side facing us. See the SDO page at http://sdo.gsfc.nasa.gov for almost-live images. They have a nice gallery of recent images at http://sdo.gsfc.nasa.gov/gallery/main.php. We have some new 3-month moving averages for sunspot numbers, and this solar cycle appears stalled, although numbers are much higher than a year ago, and are back up to the numbers seen on the downside of cycle 23 during late 2005 and early 2006. Our 3-month moving average takes the sum of all sunspot numbers for three calendar months, divides the total by number of days, and reports it as for the center month. The next month's average drops the oldest month and adds data from a new month. So the latest moving average is centered on December 2010, and takes the arithmetic average of all the sunspot numbers over the 92 days from November 1 through January 31. The total was 2,765 and the average centered on December, 2010 was 30.1. Here are the moving averages for the last four years, starting with the numbers centered on January 2007. 2007 averages were 22.7, 18.5, 11.2, 12.2, 15.8, 18.7, 15.4, 10.2, 5.4, 3, 6.9, and 8.1. For 2008 3-month moving averages were 8.5, 8.4, 8.4, 8.9, 5, 3.7, 2, 1.1, 2.5, 4.5, 4.4, and 3.6. The 2009 averages were 2.2, 2, 1.5, 2, 4, 5.2, 4, 4, 4.6, 7.1, 10.2 and 15. The 2010 averages were 22.4, 25.7, 22.3, 18.5, 16.4, 20.4, 23.2, 28.9, 33, 35.6, 31 and 30.1. I believe it was 20 years ago this week, early February 1991, when I took over writing this bulletin (without realizing it at first) from Ed Tilton, W1HDQ who had written it for so many years that I've found no one who recalls when it started. I remember copying his bulletin as a 13-14 year old on CW in 1966 from W1AW. The propagation bulletin came out on Sunday, January 7 or February 3, saying that W1HDQ was ill, and there would be no propagation bulletin from W1AW that week. Until then I had my 20 meter Yagi left pointed toward 81 degrees (short path from me to W1AW) and my Drake TR7 left on the 20-meter W1AW RTTY bulletin frequency. I copied ARRL bulletins unattended on FEC AMTOR (a serial mode with redundancy and parity bits) and after cleaning them up, I would put them out on the packet radio network via VHF. At that time the coast-to-coast packet network was not well connected, and it would often take several days for ARRL bulletins to reach the West Coast. I had been doing the same thing with the VK2SG RTTY DX Bulletin. Around the time Ed's illness was announced I noticed a dramatic rise in solar indices. The daily solar flux I copied from WWV on January 24-31, 1991 was 214, 267, 283, 303, 327, 353, 353 and 357. Solar cycle 22 was declining, and by the way, I cannot find any evidence that there have been solar flux values anywhere near this high at any time in the past 20 years. I thought it was a shame that the ARRL wasn't reporting this in a bulletin, so I called ARRL headquarters to see if the propagation bulletin would be returning the following week. The person I talked to said he didn't think so. Then I called Ed Tilton at his home
[DX-NEWS] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA February 5, 2010 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA As soon as sunspot 1041 went over the horizon at the end of January, sunspot 1043 emerged, high in our Sun's northern hemisphere. Average daily sunspot number this week fell over 13 points to 14.6, and average daily solar flux declined nearly 7 points to 75. Geomagnetic activity was up, and the average daily planetary A index rose 2 points to 5.1. Average daily sunspot number for January was 21.3, and the 3-month trailing average, centered on December, was approximately 15.2. Like last month, the average for the month greater than the 3-month average centered on the previous month is a good trend. The difference between the monthly average sunspot number and the trailing 3-month average has been positive since September. The difference for November, December and January was 0.6, 5.5 and 6.2. For 2009, the 3-month average centered on January through December resolved to two digits beyond the decimal point was 2.19, 2.02, 1.49, 2.01, 4.23, 5.2, 4, 4, 4.64, 7.1, 10.16 and 15.15. Predicted planetary A index for February 5-9 is 5, 10, 12, 12 and 5. Predicted solar flux for those same days is 80, 82, 85, 88 and 90. Geophysical Institute Prague sees quiet conditions February 5, active February 6, quiet to unsettled February 7, quiet February 8, active February 9, quiet to unsettled February 10-11. We received an interesting report recently from Peter Thulesen, OX3XR in Greenland. He writes: During the last 2 days on Tuesday February 2 and Wednesday February 3 we have in Nuuk observed shortwave conditions quite different from what we normally are used to. On around 21 UTC Jan/OX3DB was listening to very weak PSK signals on 20m from a VK5 station. Suddenly the signals were very strong for a short period where Jan worked the VK5 station. Thereafter the VK5 stations signals disappeared. Jan was not able to find out if the VK5 station signals were short-path or long-path. Later around 2200 to UTC quite heavy aurora activity was observed over Nuuk, westcoast Greenland. On February 3 around 0100 UTC the aurora observed from Nuuk area had changed from few rather strong green bands to a wide area with weak green 'clouds' covering the sky overhead from south west to north east. This evening the aurora situation was the same as observed yesterday evening. The K-index shown on NOAA site http://www.swpc.noaa.gov/aviation/index.html is quite low here late Wednesday evening and the aurora oval activity shows low activity (activity level on or below 1). When the aurora and K index are that low I wonder what causes the bad conditions observed here in Nuuk. On both days we have experienced the shortwave bands have been closing down very quick within few minutes around 22-23 UTC. Carl Luetzelschwab, K9LA sent in the following item. A really neat picture showed up at http://www.spaceweather.com on February 2, 2010 (you can view the February 2 report in the 'archives' link at the top right of the referenced web site). It's an image from the US military's DMSP-18 weather satellite. DMSP stands for Defense Meteorological Satellite program. The picture shows a thin intense band of aurora north of Norway at 1817 UTC on February 1. Why does the auroral oval image (called a pmap) indicate lots of orange, but the DMSP picture only shows a thin intense band? The reason is the auroral oval image simply indicates where visible aurora can occur based on the energy and flux of the electrons measured during the satellite pass. The auroral oval image is not a real-time picture of what's going on - it's one of ten canned pictures correlated to the ten activity levels. So don't assume an orange or red auroral oval is full of ionization. As the DMSP picture and the auroral oval image suggest, the intense auroral bands generally occur at the equatorward edge of the auroral oval. For more on what's happening in the auroral oval, visit http://mysite.verizon.net/k9la/A_Look_Inside_the_Auroral_Zone.pdf.; Thanks, Carl! Doc Kelly, K4WY of the NASA Space Operations Mission Directorate sent a link http://sdo.gsfc.nasa.gov/ to information on the new Solar Dynamics Observatory, set to launch Tuesday, February 9, 2010 around 1530z from Florida. Whitham Reeve of Anchorage, Alaska operates a magnetometer, and sent a printout showing recent geomagnetic activity. You can observe his magnetometer in action at, http://www.reeve.com/SAM/SAM_simple.html. Jon Jones, N0JK of Kansas says 6 meters really opened up on February 1, with openings all over the eastern U.S. and the southeast. Jon reports: Big 6 Meter E-skip opening January 31 and February 1. After a long dry spell, 6 Meters opened up with a bang on the last day of January. Noted Es spots on DX Summit from 1630 UTC on for stations along the
[DX-NEWS] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA January 30, 2009 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA In last week's Propagation Forecast Bulletin ARLP004, we did not have the solar flux values resolved down to a tenth of a point like we always do. Really, resolving the solar flux down to that resolution is probably not very useful, but for those who use the WA4TTK solar plotting program to suck up the data and who are compulsive enough, here are the values for January 15-21, so you can correct your data: 71.1, 70.8, 71.9, 71.1, 70.8, 70.4, 69.4, with the mean value at 70.8. On Tuesday, January 27 we saw another one of those almost-a-sunspot emerge in the Sun's low latitude, so it was probably an old Cycle 23 spot. The next day it was gone. Geomagnetic conditions continue to be very quiet, although a bit unsettled on January 26. The forecast is for more of the same. Planetary A index should stay around five, and solar flux around 70. Geophysical Institute Prague predicts unsettled conditions for January 30, quiet to unsettled January 31, and quiet February 1-5. This week we received one report about last weekend's CQ WW 160 Meter CW contest. Rod Swiderski, NU2M of Watermill, New York, reported that band conditions were outstanding. He writes, I worked 13 countries, 47 states, my first Alaskan station KL7RA (on 160) and 320 contacts. All with a mere 100 watts and a 160 dipole at 35 feet. I find it simply amazing how that band only appears 'open' during a contest. Floyd Chowning, K5LA of El Paso, Texas wrote about excellent conditions on 6 meters on Sunday, January 25. He had just put up a new 5-element antenna, and said, This morning I was running JT6M contacts with K7JIZ (DN40) and W6OUU (DN22) around 1541 UTC and signals were strong and steady. It must be sporadic-E skip. From then on the band opened up to California, Arizona, New Mexico, Texas, Louisiana, Missouri, Florida and Iowa. Also, I heard a KP4 in Puerto Rico this morning but missed his call. This afternoon I worked several stations in Mexico in EK09, DK89 and DL90 beginning around 2040 UTC. I also worked TI7/N5NEK (EK70), TI8II (EJ01) and YN2N (EK71). I worked all the stations on USB. What a day for DX on 6 Meters. I also heard HP1AC on CW but did not work him. I heard stations as close as Albuquerque, Phoenix, and Odessa, Texas, less than 300 hundred miles. I had my radio on 144.2 MHz but nothing broke my squelch. Floyd mentioned JT6M, which is a tool for running meteor scatter communications. For more about JT6M, see http://www.jt6m.org/. This week I received a copy of a remarkable old letter, sent by Jim Mast, W8HOM, of Fort Wayne, Indiana. It was written on the last day of 1975 by Ed Tilton, W1HDQ, the ham who originated the ARRL Propagation Bulletin and wrote it until 1991. This letter was addressed to Jim back when his call was K9UNM. The letter talks about 10 meter propagation via meteor scatter and the recent 1975 ARRL 10 Meter contest. It mentions W4IWZ, the call sign that belonged to Francis Harper, of Nokesville, Virginia. The letter was typed on an old manual typewriter. Here is what the letter said. Dear Jim: We certainly have heard of 10-meter meteor propagation. The date of the contest was chosen with the Geminids shower in mind. This best of the winter showers has been a factor in the contest results for all three runnings of the affair in modern times. I think the 1975 contest may have hit the shower at the most opportune time, as the effects seemed very apparent almost continually during the whole weekend. The Geminids show more night-time activity than any other shower, but there seemed to be a considerable amount of meteor burst propagation right through the whole period this year. There is always a tendency to have E propagation in mid-December, and this was also a factor in the date selection. I hope that the propaganda some people have generated for a change of season does not prevail. To my mind, this is an excellent choice. For some reason I didn't get to work W4IWZ in this contest. He and I used to be in touch almost daily, when I was at home every day, in 1973 and early 1974. I guess we've worked by means of about every form of propagation there is, at one time or another, and have seen the effects of several meteor showers. At slightly over 300 miles, he is at a very interesting distance from me. We have found that we always have a basic tropo-scatter signal, and can recognize each other on CW at almost any time. He has at least a 10-dB advantage in power, but somehow he manages to hear me every time I call him. Needless to say, I read him better than he reads me, with my 4O watts output, maximum, we have had many good QSOs, by back-scatter and short sporadic-E skip. His signal is mildly affected by tropospheric bending, too, though I'm sure we'd
[DX-NEWS] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA February 1, 2008 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA Sunspots have returned. After nearly three weeks with nothing visible (January 9-28), sunspot group 982 emerged on January 29. The very quiet geomagnetic conditions of the past week may be ending with some moderate to unsettled activity. US Air Force predicts a planetary A index for February 1-6 at 12, 10, 15, 10, 8 and 5. The next active period could be around February 9-10, with a planetary A index of 15. The period of February 16-26 is likely to see no spots, and for February 27 through March 1 we may see sunspots reappear. Geophysical Institute Prague predicts unsettled to active conditions for February 1-2, unsettled February 3-4, quiet to unsettled February 5, and quiet on February 6-7. Last year we began calculating and tracking a 3-month moving average of daily sunspot numbers. This was done to try to spot trends. A three month period seemed like it might give us some smoothing of the often volatile daily numbers, but much shorter than the official 12-month smoothed values used to calculate the solar minimum some time after it actually occurs. Now that January is done, we can calculate the 3-month moving average centered on December, 2007. The sum of all the daily sunspot numbers from November 1 through January 31 is 749, and divided by 92 days, this gives a 3-month average of 8.1. Apr 06 38.5 May 06 39.7 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 A three-month moving average may be too short to spot the actual bottom of Cycle 23, but with the steady decline from 2006 until October 2007, and a 3-month average rising from 3 to 6.9 then 8.1 since then, this suggests a cycle minimum during the Fall of last year. Four years ago in Propagation Forecast Bulletin ARLP005, for January 30, 2004 (see http://www.arrl.org/w1aw/prop/2004-arlp005.html) N6QYS (now W6JP) wondered if Cycle 23 was near minimum, and if conditions would soon improve. I looked at the weekly Preliminary Report and Forecast, and the table of predicted smoothed sunspot numbers ended in December 2007. I could see that values were expected to be lower a year from then, in January 2005. Based on this, I wondered at the time if sunspot levels might return to the predicted January 2005 level in 2008, and promised to set an alarm in my PDA for four years into the future. The actual average of daily sunspot numbers for January 2004 was 62.3, and January 2005 was 52. The following Januarys through this one had average sunspot numbers of 25.7, 28.2 and 5.1. Based on the predicted smoothed sunspot table on page 8 at, http://www.swpc.noaa.gov/weekly/pdf/prf1687.pdf, it could be some time before we are back to the 2004 and 2005 levels. So what is the difference those sunspot numbers make between 2004 and 2008? In 2004, the 20 meter path from San Francisco to Japan should stay open 2130-0500z, with best signals toward the end of that period. But for tomorrow, that path would probably open between 2230-0030z. 15 meters would open 2200-0200z in 2004, but perhaps 2300-2330z. Similarly, Chicago to Germany in those days on 15 meters was probably open 1530-1830z, but today not open at all. On 20 meters today the path would likely open 1530-1730z, but in 2004 it was 1400-1900z 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 web page 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 January 24 through 30 were 0, 0, 0, 0, 0, 13 and 14 with a mean of 3.9. 10.7 cm flux was 71.3, 71, 72.5, 72, 71.3, 71.6, and 72.7 with a mean of 71.8. Estimated planetary A indices were 5, 11, 5, 2, 2, 4 and 2 with a mean of 4.4. Estimated mid-latitude A indices were 3, 8, 6, 2, 2, 3 and 1, with a mean of 3.6. /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 To subscribe/unsubscribe, please send request to [EMAIL PROTECTED] and allow a few hours for acknowledgement --
[DX-NEWS] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA February 3, 2006 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA Solar activity is very low. Average daily sunspot numbers for the week were down over 40 points to 9.1. Average daily solar flux dropped nearly 11 points to 80.6. Geomagnetic conditions, with the exception of January 26 were stable and quiet. On January 26 the interplanetary magnetic field, which can shield the earth from solar wind if it is pointing north, turned south, and the mid-latitudes experienced some moderate geomagnetic activity, with the A index for the day at 15. Polar regions saw a lot more activity, with the College A index in Alaska going to 36. Currently the sun is spotless since January 29. Daily readings of zero sunspots could continue for another week. We will observe more and longer periods such as this as we head toward the solar minimum, still expected about to occur about a year from now. Geomagnetic conditions should remain quiet, and solar flux around 77. This may not begin to rise again until February 10. January is over, so let us examine the average daily solar flux and sunspot numbers for the month compared with previous months. The average daily sunspot numbers for the months January 2005 through January 2006 were 52, 45.4, 41, 41.5, 65.4, 59.8, 68.7, 65.6, 39.2, 13, 32.2, 62.6 and 26.7. Average daily solar flux for the same months was 102.3, 97.2, 89.9, 85.9, 99.5, 93.7, 96.5, 92.4, 91.9, 76.6, 86.3, 90.8 and 86.6. As expected, the solar cycle is declining, but there is a lot of variation from month to month. Richard Buckner, who wrote the ACE-HF and ACE-HF Pro System Simulation and Visualization Software for propagation prediction mentioned in response to last week's bulletin that ACE-HF can do 160 meter predictions, but with some limitations. He sent along a quote from the ACE-HF Basis for Predictions tutorial, written by George Lane: 160-m Prediction Accuracy. 160-m frequencies are rounded to 2.0 MHz to conform to VOACAP's lower frequency limit. VOACAP 2-MHz predictions are reasonably accurate for NVIS and short-range predictions out to about 1500 km. But when path distances are very long, VOACAP becomes less accurate at night. At night, a residual E-layer exists with a MUF usually above 2 MHz. It is this phenomenon that permits AM broadcasts in the medium-wave bands to propagate thousands of kilometers during nighttime hours. VOACAP, however, is based on data that was collected at frequencies of 4 MHz and higher. Extrapolation was used to cover the lower frequencies, but funding limitations prevented the collection of further data to support those extrapolations. Unfortunately, computed absorption values are excessive in the extrapolations and the nighttime predictions thus become excessively attenuated as path distance increases. For this reason, 160-m nighttime predictions at long path distances should be used with caution. You can find more information on ACE-HF at, http://home.att.net/~acehf/. We heard again from Charles Lewis, S9SS of Sao Tome (an island off the West African coast, west of Gabon). On January 20 he wrote, I made 150 - 160M contacts last week. 51 were in North America, coast to coast. It was, as usual, very slow, tedious going. E-mails to me cited large pileups. As usual, I heard no pileup. Usually, I hear only one, occasionally two, stations cresting my high level noise. Even most big gun stations only get through when their signal is enhanced greatly by whatever propagation phenomenon. Even little guns find themselves all alone in the spotlight on my stage now and then, despite all the better equipped callers. There is no such thing as cracking the pileup on me on 160 meters since I never hear it. Charles continues, In the Stew Perry, I heard only five NA stations in close to three hours of listening and worked all five easily. It was interesting that I heard one station on and off for nearly two hours, while I heard the others only briefly for one period. He goes on to say, An interesting quirk here is a rogue LU 10 meter beacon that I hear often on the IARU beacon frequency for hours at a time when the band is so dead that I hear none of the IARU beacons. Weird!! I favor the W3VD beacon when I am specifically looking for an opening to the USA on 10M since, unlike 4U1UN, it transmits continuously on 10 M. He continues, I used to experience the antipodes enhancement phenomenon on the upper bands often when I was A22AA in 89-92. I would often work Hawaiian hams (and hear WWVH) when the bands were nearly in a blackout condition. 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 and an explanation of the numbers used in this bulletin see the ARRL Technical Information Service propagation page at,
[DX-NEWS] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA February 4, 2005 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA Average daily sunspot numbers were down this week by nearly 17 points (our reporting week runs from Thursday through the following Wednesday for the timing of this bulletin). Over the same days the average daily solar flux was also down nearly 17 points. The daily geomagnetic indices showed much greater stability, with all of the K and A indices down when compared with the previous seven days. Look for quiet geomagnetic conditions over the next few days, with the February 4-6 (Friday through Sunday) planetary A index around 8, 5 and 5. The A index is expected to rise again after this weekend probably due to the return of sunspot 720, which caused so much recent activity. It returns into view on its 27.5 day rotation, and the planetary A index prediction for February 7-9 is 15, 25 and 15. Sunspot numbers and solar flux should also rise, with solar flux values rising above 100 after February 5, staying relatively high (for this point in the declining sunspot cycle) at 130 or above around February 7 and continuing for about a week. If you would like to comment or have a tip, email the author at, [EMAIL PROTECTED] For more information concerning 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. Sunspot numbers for January 27 through February 2 were 43, 43, 30, 38, 49, 27 and 28 with a mean of 36.9. 10.7 cm flux was 86.9, 84.9, 86.4, 85.5, 86.2, 83.7 and 81.8, with a mean of 85.1. Estimated planetary A indices were 3, 6, 20, 16, 19, 6 and 8 with a mean of 11.1. Estimated mid-latitude A indices were 2, 5, 16, 10, 15, 4 and 7, with a mean of 8.4. /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] ARLP005 Propagation de K7RA
SB PROP @ ARL $ARLP005 ARLP005 Propagation de K7RA ZCZC AP05 QST de W1AW Propagation Forecast Bulletin 5 ARLP005 From Tad Cook, K7RA Seattle, WA January 30, 2004 To all radio amateurs SB PROP ARL ARLP005 ARLP005 Propagation de K7RA There are no sunspots. The visible solar disk is blank. This prompts email inquiring if it's normal to see a spotless sun at this point in the solar cycle. Yes, it is normal, because there are big variations from day to day. In order to generalize and see the larger trends, we need to calculate a very smooth running average, where readings from many days or months are averaged together. An example of a smooth chart using running or moving averages of many data points can be seen on the web at http://www.ngdc.noaa.gov/stp/SOLAR/SSN/annual.gif or http://www.dxlc.com/solar/cyclcomp.html. There is an explanation of how a smoothed sunspot number is calculated based on 12 months of averaged data at, http://www.ngdc.noaa.gov/stp/IONO/sunspot.html. There is also a very interesting graphic representation of the difference between a running average based on 12 months and the averages for each individual month over the same period at, http://www.meadows3.demon.co.uk/html/trends.html. For the 12 months of data there is still a point on the graph for each day, but that point represents all the data from 6 months before and 6 months after, averaged together. The point for the next day is the same, but drops one day off at the back end and averages in another day's data from 6 months in the future. This is why reports showing the current smoothed sunspot number always must be at least 6 months in the past. In that chart at the previous web link, those tiny colored diamonds each represent a month of averaged data, just like those averages presented frequently in this bulletin. An example of those monthly averages is in 2003's Propagation Forecast Bulletin 49, at http://www.arrl.org/w1aw/prop/2003-arlp049.html. Jeffrey Philpott, N6QYS wrote to ask if the solar cycle is near bottom, and how long until conditions improve? If we look at the end of a recent (January 6) issue of the NOAA Preliminary Report and Forecast of Solar Geophysical Data at http://www.sec.noaa.gov/weekly/pdf/prf1479.pdf, it shows a projection of future sunspot and solar flux values for nearly the next four years, until December 2007. This is a rough guess based on previous solar cycles. We can see from both spreadsheets that the predicted bottom of the cycle is expected to occur some time around the end of 2006, although given what we covered above concerning long moving averages, we won't know when the bottom occurs until some time after we've passed it. We could assume that as we examine projections for rising values during the next cycle, an estimate could be made for when conditions should improve past the current level by looking for a value that matches current conditions. Unfortunately, the data doesn't go that far into the future. The best we can say is that a year from now conditions should be worse, and that the projected number for January 2005 doesn't rise back to that same level until December 2007. Because January 2005 is a year from now, could we assume that current conditions will worsen and not be at this level again until December 2008? We can't really do that, because solar cycles tend to rise faster than they decline, but a wild guess could be that some time in 2008 conditions will be back up to where they are now. We can all make notes in our PDA to check back to this bulletin in 2008 and see if we were far off base. I've done this, and four years from now I should be quite surprised to see this note from the past. Conditions will likely improve somewhat over the next week. The weekly average of daily sunspots for this week was half what it was the week before. Average daily solar flux declined over 21 points. Projected solar flux for Friday through Monday, January 30 through February 2 is 90, 90, 100 and 100. Solar flux is expected to peak for the short term around February 8. Geomagnetic conditions may be rough over the next week, unsettled to active. The predicted Planetary A index for January 30 through February 5 is 15, 20, 20, 25, 25, 15 and 10. Yesterday's ARRL DX Bulletin reported that this weekend is the UBA DX SSB Contest. The CW section will be in February, but the target in this competition is to work as many European stations on the five non-WARC HF bands, and especially Belgian stations. Working Belgium is worth 3 times the points counted for contacts with other European countries. We won't hazard to guess when 80 and 40 meters should be good for working Belgium or the rest of Europe, but here are some projections for bands higher than 40 meters. From Seattle, best conditions look to be on 20 meters after local sunrise, 1630-1900z, and a weak possibility on 15 meters around 1630-1700z. There is another possible opening on 20, although not as strong, after local sunrise
