K7RA Propagation Bulletin #50 (updated on: 07/Dec/13)
SB PROP @ ARL $ARLP050 ARLP050 Propagation de K7RA ZCZC AP50 QST de W1AW Propagation Forecast Bulletin 50 ARLP050 From Tad Cook, K7RA Seattle, WA December 6, 2013 To all radio amateurs SB PROP ARL ARLP050 ARLP050 Propagation de K7RA Due to the Thanksgiving holiday in the United States (Canada celebrates the same holiday on the second Monday in October, same as Columbus Day in the United States) we had a short bulletin on Wednesday last week, and a catch-up bulletin on Monday morning, December 2. If you missed it, you can read it online at http://www.arrl.org/w1aw-bulletins-archive/ARLP049/2013 and see last week's early bulletin at http://www.arrl.org/w1aw-bulletins-archive/ARLP048/2013 . Solar activity bounced back this week, with average daily sunspot numbers increasing from 63.6 to 102.9, and average daily solar flux from 130 to 132.9. There were no periods of disruptive geomagnetic activity, although November 30 and December 1 were slightly unsettled. There was another uptick in activity yesterday, December 5, when the solar flux readings at Penticton were 157 at 1800 UTC, 149.6 at 2000 UTC and 156 at 2200 UTC. The daily reading at 2000 UTC (local noon in British Columbia) is always the official solar flux value for the day. The sunspot number for December 5 was 103, up from 98 the day before. Predicted solar flux for December 6-7 is 155, on December 8-9 it is 150, then 145 on December 10-11, 135 on December 13-14, 130 on December 15-16, 135 on December 17, 130 on December 18-19, 125 and 130 on December 20-21, 125 on December 22-23, 130 on December 24-26, and 125 on December 27-28. There is an odd solar flux peak at 165 predicted for January 8, but this seems to be a remnant of a prediction from November 25 through December 1, when there were many days in mid-December, late December and early January with solar flux predicted at 160-165. On December 2 these predictions were radically revised downward, with the exception of January 8. From November 25 to December 1 the solar flux prediction was 165 for January 4-10, but starting on December 2 that prediction was revised to solar flux at 130 on January 4-7 and 135 on January 9-10 and 130 on January 11-12, with January 8 standing alone at 165. You can see these changes at http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html, at least for a few weeks. Predicted planetary A index is 8 on December 6, 12 on December 7-8, 5 on December 9-12, then 10 and 8 on December 13-14, 5 on December 15-25, then 12, 10, 8, 12 and 10 on December 26-30. OK1HH sends his geomagnetic prediction from the Czech Republic. He sees quiet to unsettled conditions December 6-7, mostly quiet December 8-11, active to disturbed December 12, quiet December 13-14, mostly quiet December 15, quiet to unsettled December 16, quiet December 17-18, quiet to unsettled December 19, quiet December 20-24, mostly quiet December 25, quiet to unsettled December 26, quiet to active December 27, quiet December 28, mostly quiet December 29, and quiet on December 30-31. NASA released a new Solar Cycle Prediction, but nothing has changed except the date: http://solarscience.msfc.nasa.gov/predict.shtml Actually the information seems a bit dated, but of course they are dealing with smoothed sunspot numbers, which are immune to daily variations. The smoothed sunspot number is an average for an entire year, so we are always six months behind in knowing the latest real smoothed number. Go to http://www.swpc.noaa.gov/weekly/pdf/prf1992.pdf and note the numbers for January through April 2013 on page 18. This report is over a month old, but at that time the April 2013 value was the latest known smoothed number. Each month after that incorporates progressively less real sunspot data and more predicted numbers. But also note that in this table they show the current cycle peaking in April and May of 2014. So we may not be at the peak for this cycle after all. Larry Godek, W0OGH of Gilbert, Arizona sent this: "I was listening on Tuesday afternoon (December 3) for VU7AG, weakly on SSB and then with a polar sound later in the PM. Had called him a couple times on CW early on with no response but the frequency was crowded with people all over the place hearing him apparently. Working on the bench and listening at the same time, kinda. Well the signal seemed to be getting stronger and after donning the headset I could not hear as many stations calling him as before but he was working a lot of 7-land and 0 call area stations. I tuned around up and down about 2 KHz from his frequency but couldn't hear any of the stations he was calling. "Then I heard a good loud 7-land station go back to him with the exchange. I quickly zero beat him and when the VU7 stood by I gave him a quick call. He came back to a W0, so I called him again and he came back with my call. That was at 2151:30 on December 3 on 14.030 MHz. That was really the only time during all of his operating that I really heard him well enough to make a contact. I had heard him on SSB but getting into that fray with only 100 watts and a low 4 element Yagi doesn't get me many contacts against the multi-KW and 100ft plus stacked beam stations. "Then at 2301 I worked JA3HAW and at 2304Z I worked JH0KZQ on 29.6 MHz FM. I've worked Europe and South America on 29.6 FM, but it's been many a year since I even heard a JA on that frequency. I thought I heard some Russian stations as well but not knowing the language it was hard to tell where they were from. Then today, December 4 at almost the exact same time I worked the JA3 and JH0 stations, again on 29.6. They were calling CQ DX. I didn't hear them go back to any other station before the path was lost. "BTW, I have heard nothing of the VU7 again since yesterday although I hear lots of other stations working him." If you would like to make a comment or have a tip for our readers, email the author at, firstname.lastname@example.org. For more information concerning radio propagation, see the ARRL Technical Information Service web page at http://arrl.org/propagation-of-rf-signals. For an explanation of the numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere. An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation. More good information and tutorials on propagation are at http://k9la.us/. Monthly propagation charts between four USA regions and twelve overseas locations are at http://arrl.org/propagation. Instructions for starting or ending email distribution of ARRL bulletins are at http://arrl.org/bulletins. Sunspot numbers for November 28 through December 4 were 100, 95, 102, 104, 124, 97, and 98, with a mean of 102.9. 10.7 cm flux was 132.9, 128.5, 131.2, 130.5, 133.7, 135.7, and 138, with a mean of 132.9. Estimated planetary A indices were 2, 8, 9, 10, 2, 7, and 4, with a mean of 6. Estimated mid-latitude A indices were 1, 6, 7, 7, 1, 6, and 3, with a mean of 4.4.
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