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The K7RA Solar Update


Tad Cook, K7RA, Seattle, reports: Sunspots returned on October 9 – 12, with sunspot numbers of 24, 26, 15 and 15. No sunspot appeared on October 13, but late on Wednesday, October 14, reported a new emerging Solar Cycle 25 spot on our sun’s southeastern limb, and a daily sunspot number of 12. The next day, NOAA reported sunspot numbers of 12 and 14 on October 14 – 15. Prior to October 9 no sunspots appeared for 2 weeks, and at that time we saw a sunspot number of 13 on September 23 and 11 on September 25.

Average daily sunspot number increased from 0 to 13.1, while average daily solar flux went from 71.8 to 73.1.

Geomagnetic indicators were lower, with planetary A index dropping from 7.1 to 2.7 and middle latitude A index from 6 to 1.9.

Predicted solar flux for the next 45 days is 74 on October 16 – 17; 72 on October 18 – 31; 70 on November 1 – 7; 73 on November 8 – 10; 72, 71, and 71 on November 11 – 13; 70 on November 14 – 23; 72 on November 24 – 27, and 73 on November 28 – 29.

Predicted planetary A index is 5 on October 16 – 19; 10 on October 20; 8 on October 21 – 23; 16, 38, and 38 on October 24 – 26; 26, 15, and 10 on October 27 – 29; 5 on October 30 – November 6; 10 on November 7; 5 on November 8 – 15; 10, 15, and 18 on November 16 – 18; 20 on November 19 – 20; 24, 14, and 10 on November 21 – 23; 8 on November 24 – 25, and 5 on November 26 – 29.

F.K. Janda, OK1HH, filed this report.

The geomagnetic field will be:

  • quiet on: October 16, November 5 – 7, 10 – 13 
  • quiet to unsettled on: October 17, 31, November 3, 14 – 16 
  • quiet to active on: October (18,) 19 – 20, 28 – 29, (30,) November (1, 4) 
  • unsettled to active: October 22, (24,) 27, November 2, 8 ( – 9) 
  • active to disturbed: October (21, 23,) 25 – 26 
  • Solar wind will intensify on October (20 – 21,) 22, (23 – 25,) 26 – 29, (30,) 31, November (2 – 3,) 4 – 5, (9 – 11).

Note: Parenthesis means lower probability of activity enhancement.”

Do you think the recent (or current) solar minimum is lasting a little too long? Check this contrarian view. Note the link toward the bottom of the page. It shows sunspot records and predictions from 1730 until 2101! I can’t explain the numbers or how they were derived.

Perhaps someone can help this programmer on Stack Overflow with his Python program for performing linear regression with a sunspot database.

On Thursday, October 15, on the local Puget Sound Repeater Group 146.96 MHz machine, I heard a couple of stations talking about gray-line, long-path propagation on 40 meters. After I inquired, Dean Holtan, N7XS of Camano Island, Washington wrote:

“On Wednesday, October 14, at 1530 UTC, I heard K6MYC and company working ZS6 stations. I also heard a station in the Netherlands, PA1A I believe. He was very loud along with the ZS6 stations, S-9 plus via long path.

“I was listening on my SDRplay RSPduo and a 160-meter loop at 100 feet. If I had gone to the shack I could have worked them. Thursday October 15, 20 meters was nicely open into Europe. KW7Y was working many G stations and EA short path at 1630 UTC. The above was all on phone.

“Last week on October 10 starting at 0130 UTC when I was on vacation, on 20 meters at our sunset I worked UN7JX and VU2MB along with many others in Asiatic Russia. I was called by a station in Lebanon but that was unsuccessful — all on FT8 running 500 W and my 160-meter loop at 100 feet from Camano Island, Washington.”

Doug Behl, VE3XDB, linking via internet from Kitchener, Ontario, later wrote:

“Many amateurs today complain about propagation. Conditions haven’t been great for several years, although there is some glimmer of hope that things may be getting better. Those experiencing the most frustration seem to be sideband operators. I have had some success over the past few years, using a couple of principles.

1. Use a mode that does better in poor conditions. These days, everyone jumps to FT8, a fantastic, low-power mode that does very well in poor conditions. However, I prefer a mode that creates a more traditional experience. CW and PSK31 are both very good modes for effective contacts when conditions are poor and may provide an opportunity to get to know the other operator a bit better.

2. Work the gray line. Gray-line propagation occurs at daybreak or at dusk. It is very interesting, because it occurs at a very particular time of day, opens up very quickly, and then, when time is up, it just disappears! Here is a short, interesting article on the science and experience of gray line propagation.

Following the above two principles, I have worked western and eastern Europe, the Caribbean and South America, as well as Oceania and Southeast Asia over the past few months, My modest station is a short, inverted L and an old Kenwood transceiver, usually running about 20 W and never more than 40 W. Best results have been achieved on 20, 30, and 40 meters.

To work the world when conditions are poor, I encourage others to try CW and PSK31, especially at dawn or at dusk. You may be surprised by the results achieved using a modest station. We need more operators in both of these modes!”

Ken Brown, N4SO wrote:

“Evidence pointed to a very good propagation path to Asiatic Russia, Japan, and to China on Saturday evening. From October 10, 2330 UTC, 21.074 MHZ, FT8: I first noticed UA0CA calling CQ from Asiatic Russia. It’s rare to see a UA0 on the screen, and so far I have never completed a contact. I have also never had completed a contact with China until Saturday evening.

“Calling UA0CA was noticed by BV1EK, China, and he called me and we were able to complete a contact. In this same period, I completed contacts with JA1FGX, JQ1CIV, and JG1SRB.

“A contact with UA0CA or with UA0ZK was not made, but I can appreciate the distance is roughly 5,000 miles away. I will try again on Sunday. Distance to UA0ZK, for example, is 5,391 miles.”

Sunspot numbers for October 8 – 14 were 0, 24, 26, 15, 15, 0, and 12, with a mean of 13.1. The 10.7-centimeter flux was 71.6, 73.1, 73.6, 72.9, 73.8, 72.3, and 74.5, with a mean of 73.1. Estimated planetary A indices were 3, 2, 2, 3, 4, 3, and 2, with a mean of 2.7. Middle latitude A index was 2, 1, 2, 2, 3, 3, and 0, with a mean of 1.9.

For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out K9LA’s Propagation Page.

A propagation bulletin archive is available. Monthly charts are no longer be updated on this page. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.

Instructions for starting or ending email distribution of ARRL bulletins are on the ARRL website. 

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