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The K7RA Solar Update


Tad Cook, K7RA, Seattle, reports: Our closest star seems to have quieted again. We have now experienced 7 consecutive days with no sunspots.

Average daily sunspot number dropped from 5.4 to 1.9 this week, and average daily solar flux declined from 71 to 70.4. Geomagnetic indicators increased marginally, with average daily planetary A index going from 4.4 to 5.1, and average middle latitude A index from 5 to 6.

Predicted solar flux is 70 on August 28 – September 3; 71 on September 4; 72 on September 5 – 9; 71 on September 10 – 16; 70 on September 17 – 27; 71 on September 28 – 30; 72 on October 1 – 6, and 71 on October 7 – 11.

Predicted planetary A index is 8, 10, 12, and 8 on August 28 – 31; 5 on September 1 – 17; 8 on September 18 – 19; 10, 15, and 10 on September 20 – 22; 5, 10, 12, and 18 on September 23 – 26; 15 on September 27 – 28; 12 on September 29, and 5 on September 30 – October 11.

OK1HH is on his annual hiatus, so no geomagnetic prediction from him this week. Instead, we present a much more limited forecast from Tomas Bayer of the Budkov Observatory in the Czech Republic. Geomagnetic activity forecast for the period August 28 – September 3:

  • Quiet: August 27, Sep 1 – 3

  • Unsettled: August 27 – 31, Sep 1 – 2

  • Active: possible August 30 – 31

  • Minor storm: 0

  • Major storm: 0

  • Severe storm: 0

Geomagnetic activity summary: Friday, August 28, we expect the most quiet conditions yet. Friday evening, more unsettled conditions are possible. The most unsettled conditions are expected over the weekend, Saturday, August 29, and Sunday, August 30. The unsettled stage can also peak by any isolated active event.

After Monday, August 31, we expect waning of the unsettled conditions to quiet-to-unsettled level. The first 3 days of September, we expect quiet conditions to return. — Tomas Bayer, RWC Prague, Institute of Geophysics of the ASCR Prague, Department of Geomagnetism, Budkov Observatory

Since sunspots are fading (I assure you this is temporary) we have received another of the occasional reminiscences of Solar Cycle 19, this one from Bill, W5EC.

“I would love for everyone to experience another cycle 19 in the next 10 years.

“I received my Novice license in 1954 at the age of 16. My station was an S-38 and a homemade 6V6 xmtr on 80 meters, crystal controlled. Later, I was given a 40 meter crystal and I enjoyed more-distant QSOs. One night I was called by a very strange call, and I learned that I was talking to CM7JA in Camaguey, Cuba. My first DX, and I was hooked. I built a mighty Heathkit AT-1 and moved to 15 meters in my quest for DX. Hawaii was my first DX on 15.

“I received my General in 1955, and built a Heathkit VFO. Now I was set for DX. In late 1954, the SSN was bouncing around 5, good for 80 and 40. In late 1955 the SSN was bouncing around 70, and 20, 15, and 10 were alive with signals from everywhere. I upgraded to an NC-98 receiver and a Globe Scout transmitter, and in late 1956 the SSN was about 160. I thought DX could not be better than this.

“But it did! I built a homemade 10-meter beam made from bamboo poles wrapped in aluminum foil and could contact anyone I could hear. By the end of 1957, the SSN was 200 with excursions to 250. All the high bands were open all night long. It was fantastic! Most of my operation was on CW with an occasional QSO on AM, if I heard a new one.

“By 1958, school and girls competed with radio for my attention, but I always found some time to operate. SSN was still up around 160. Soon it was graduation, job, marriage, and kids but I always found time to flip the new-and-improved rig on. I was also working on getting those elusive QSL cards to improve my DXCC standing.

“Now at 82, I am still working DX but mostly on FT8, and I am looking forward to an exciting Solar Cycle 25. I hope y’all can experience what I did.

” -- Bill, W5EC. DXCC #1 Honor Roll/Mixed: 362/340/CW: 346/339

Thanks, Bill, for the report from the mid-20th century. Nice to hear of a Yagi built from bamboo poles wrapped in aluminum foil.

I hope we see more sunspots soon, and one thing we have to look forward to currently is improved propagation due to seasonal effects. We are just a few weeks away from the autumnal equinox.

Here’s a new video from Tamitha Skov, WX6SWW, the Space Weather Woman.

Sunspot numbers for August 20 – 26 were 13, 0, 0, 0, 0, 0, and 0, with a mean of 19. The 10.7-centimeter flux was 69.9, 70.9, 70, 70.6, 70.3, 70.6, and 70.4, with a mean of 70.4. Estimated planetary A indices were 3, 4, 8, 7, 3, 4, and 7, with a mean of 5.1. Middle latitude A index was 4, 5, 13, 7, 3, 3, and 7, with a mean of 6.

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.

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