SB PROP @ ARL $ARLP023 ARLP023 Propagation de K7RA ZCZC AP23 QST de W1AW Propagation Forecast Bulletin 23 ARLP023 From Tad Cook, K7RA Seattle, WA June 8, 2018 To all radio amateurs SB PROP ARL ARLP023 ARLP023 Propagation de K7RA Sunspots vanished again after appearing on every day, from May 21 through June 4. Average daily sunspot numbers this week (May 31 through June 6) dropped from 26.3 to 12.9. Average daily solar flux declined from 74.9 to 73.2. Average planetary A index increased from 3.9 to 11.7 while average mid-latitude A index increased from 4.7 to 10.4. Predicted solar flux is 69 on June 8 to 10, 70 on June 11 to 14, 72 on June 15 to 17, 74 on June 18 to 23, 72 on June 24 to 30, 73 and 72 on July 1 and 2, 70 on July 3 to 7, 72 on July 8 to 14, 74 on July 15 to 20 and 72 on July 21 and 22. Predicted planetary A index is 5 on June 8 to 12, 8 on June 13, 5 on June 14 to 18, 8 on June 19, 5 on June 20 to 26, then 15, 28 and 18 on June 27 to 29, 10 on June 30 through July 1, 8 on July 2, 5 on July 3 to 9, 8 on July 10, 5 on July 11 to 15, 8 on July 16, and 5 on July 17 to 22. Summer solstice in the Northern Hemisphere is coming up in less than two weeks, on Thursday, June 21, just before ARRL Field Day weekend. Around this time of year we may see sporadic-E propagation on ten meters, and sometimes on six meters. Check this site devoted to ten meter sporadic-E: http://www.chem.hawaii.edu/uham/spore.html June 23 and 24 is Field Day weekend. Predicted solar flux of 74 and 72 looks promising, and the planetary A index prediction of 5 for both days is excellent. Previously the planetary A index was predicted at 8 for Sunday, and 5 is better. Bill Mader, K8TE, president of the Albuquerque DX Association wrote: "I hope you and Dr. Skov can educate folks about HF communications on the planet Mars. Although Mars' atmosphere is approximately 0.6 per cent of Earth's, https://en.wikipedia.org/wiki/AtmosphereofMars there are sufficient atoms to provide an ionosphere according to some scientists (see https://bit.ly/2xTY06z). However, reading this paper, it's obvious the authors do not have a lot of experience with the subject since they state the Mars ionosphere 'reflects' radio signals, rather than refracts them. Long ago, I gave a presentation to a middle school class on this very subject. This is before the scientific community knew about Mars' complicated atmosphere, much less its ionosphere. I suggest satellite communications would be necessary between explorers on Mars' surface. It may well be you will eventually need to provide HF propagation predictions for hams on Mars." VK5EEE wrote, regarding a recent inquiry on HF beacons: "Beacons on bands other than 10m on HF (28200 to 28300 kHz) are discouraged by the IARU, however, there are a few exceptions that have been approved (and many unapproved beacons). The most famous and useful is DK0WCY. The German website (with a few pages in English) has a wealth of information. I have also corresponded with DDK9, the German RTTY WX station on 30m and obtained information about that station too. To make it easy for hams, I have put together pages that make it easy to find what you need about these. Please take a look: http://www.30cw.net/dk0wcy and http://www.30cw.net/ddk9 A very fun beacon is IY4M that is licensed just below the 10m exclusive beacon band (28200 to 28300) on 28195, and also on 12m. It is extremely hard to find information about this beacon, which is sad, as it is an amazing work. You can QSO with the beacon in CW and it is very friendly and upbeat, you give it various commands, such as to speed up, slow down, send this or that info, etc. I used to love having regular QSOs with it from Europe especially during Sporadic E seasons. All best wishes, 73 de Lou VK5EEE" This is from George Ockwell, K7HBN: "Perhaps it occurred too late in the reporting period, but I'm surprised you didn't receive any comments on the exceptional conditions during the WPX CW Contest. Here in Western Washington 20 meters was open to somewhere the full 48 hour period. The SFI was 74 to 75 with the A Index 4 to 5 and the K Index 0 to 1. 15 meters was open to South America with some JA as well. Brief openings also happened on 10 meters." That was last weekend on May 26 and 27. See https://www.cqwpx.com/ Here is a propagation resource for the upcoming Baker Island DXpedition: http://www.baker2018.net/pages/propagation.html Other resources from K6TU: https://www.k6tu.net/ For more information concerning radio propagation, see the ARRL Technical Information Service at http://arrl.org/propagation-of-rf-signals. For an explanation of 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 May 31 through June 6, 2018 were 21, 22, 20, 16, 11, 0, and 0, with a mean of 12.9. 10.7 cm flux was 76.8, 74.8, 74.4, 73.6, 70.5, 71.3, and 71.1, with a mean of 73.2. Estimated planetary A indices were 12, 26, 17, 9, 5, 6, and 7, with a mean of 11.7. Estimated mid-latitude A indices were 11, 19, 14, 9, 5, 6, and 9, with a mean of 10.4. NNNN /EX