sabato 23 luglio 2022

The K7RA Solar Update

Solar activity increased over this reporting week, July 14 to 20, with average daily sunspot number rising from 102.1 to 137.3, and average daily solar flux from 147.4 to 157.6.

Peak sunspot number was 166 on July 17, and peak solar flux was 171.4 on July 15.

Geomagnetic activity peaked on July 19 when planetary A index was 26 and middle latitude A index at 19. Alaska's high latitude college A index was 43, with the K index at 6, 5, 5, 6 and 5 at 0900 to 2000 UTC.

Average daily planetary A index decreased this week from 12.4 to 9.4.

A crack opened in the earth's magnetic field on July 19, allowing

solar wind to stream in. It is documented here:

At 2241 UTC on July 20 the Australian Space Forecast Centre issued a geomagnetic warning. An increase in geomagnetic activity is expected over 22 to 24 July due to the onset of coronal hole high speed wind streams."

Here is the latest forecast from USAF. Predicted solar flux seems promising with flux values peaking around 160 on July 30 through August 7 and again from August 26 through early September. Predicted flux values are 120 on July 22, then 118 on July 23 to 25, then 116, 114, 110 and 120 on July 26 to 29, 160 on July 30 through August 7, then 155, 145 and 138 on August 8 to 10, then 138 on August 11 and 12, then 128 and 125 on August 13 and 14, 130 on August 15 to 17, 135 on August 18 to 20, 138 and 148 on August 21 and 22, 150 on August 23 to 25, and 160 on August 26 to September 3.

Predicted planetary A index is 20, 40, 14 and 10 on July 22 to 25, 5 on July 26 to 28, 8 on July 29 through August 2, then 12 and 10 on August 3 and 4, 8 on August 5 to 7, then 15, 28 and 12 on August 8 to 10, 8 on August 11 to 17, then 15, 20 and 12 on August 18 to 20, and 8 again on August 21 to 29.

OK1HH wrote:

"A week ago we commemorated the BASTILLE DAY EVENT. Twenty-two years ago (on the French national holiday of July 14, 2000), the Sun sent out a shock wave that reached the edge of the solar system. The subatomic particles accelerated by the eruption showered satellites and penetrated deep into the Earth's atmosphere. Radiation sensors on the Earth's surface detected a rare GLE – a ground-level event. And if solar activity continues to grow as it is now, we will see something similar in the years to come.

The most notable recent event was a crack that opened in Earth's magnetic field on July 19th, allowing solar wind to enter our planet's magnetosphere. The result was a minor G1-class geomagnetic storm. Starting today, July 21, a slow-moving CME could hit Earth's magnetic field (thrown into space by the July 15 solar flare). The high-speed stream of the solar wind should follow closely behind the CME. Its arrival on July 22nd could intensify any storm the CME creates, possibly extending the disturbance until July 23rd.

In addition, solar activity will decrease in the coming days, which combined with G1 is not good for shortwave propagation conditions."

Rich, K1HTV wrote:

"Yesterday evening, July 19, 2022 there was an incredible 6 Meter DX opening between VK4 and many lucky stations in the U.S. as well as the Ontario area.

At 2311 UTC I decoded VK4MA completing a QSO with KD3CQ in southern MD. I was next in line, and quickly worked VK4MA from my FM18ap Virginia QTH. I was followed by W3UR, W3LPL, AB3CV, N3OC and W3KX, all in MD and KF2T and K4SO in VA.

Two minutes after working VK4MA I also worked VK4WTN, I also copied but did not work VK4HJ.

I continued to decode the VK4 stations until 2358 UTC. I copied VK4MA working K8SIX in MI, W7XU in SD, N0TB in MD, VE3EDY and as far northeast as NZ3M in PA, N2OO, W2XI and W2IRT in NJ, W1VD in CT, WA1EAZ in MA and K1TOL in Maine, which was Paul's longest ever 6 Meter DX contact. VK4MA reported logging 27 stations during his almost one hour long DX opening to North America.

To say the least, it was a very memorable opening on the Magic Band. The solar flux was near 180 a few days earlier and a K index of 5 earlier in the day of the opening. Was it F2 skip? Was it TEP? Was it SSSP? (Short Path Summer Solstice Propagation, see

It was some kind of chordal propagation, probably linked to the Es opening from the East to Mid-America at the time. I'll leave it up to the propagation experts to figure out what mode it was."

I assume he was using FT8, as Rich said "decoded."

Jon Jones, N0JK responded:

"A great report from Rich. I was monitoring at the time. Saw many people north and east of Kansas calling VK, but no decodes of VK stations. What a great opening!

As for the propagation mode - my theory is the opening yesterday was a "mirror image" of the December-January USA-VK openings. So sporadic-E on each end of the path connecting to TEP to cross the geomagnetic equator. I have seen K0GU work VK stations in past summers on 6 in a similar fashion. The high solar flux helped the TEP part of the path. But sporadic-E created the magic."

George, N2CG has been operating on the 8 meter band with special permission from the FCC. Below is an edited version of some of the notes he sent me.

"Back in October 2021 I received from the FCC an experimental radio station construction permit and license to operate on 40.66 to 40.7 MHz and issued the call sign WM2XCS.

On 26 January 2022 WM2XCS began transmitting as a CW beacon on 40.685 MHz at 10 Watts output into a vertical ground plane antenna.

On 26 May I made some changes by removing the vertical antenna and in its place installed a 4 element 7 dBd gain Yagi mounted 30 feet above ground beaming toward Europe and increased the beacon output power from 10 Watts to 20 Watts.

Now using shorter ID message at 12 WPM, 'VVV DE WM2XCS/B FN20WV NNJ AR'. I also increased the output power from 20 Watts to 30 Watts that equates to 150 Watts ERP which is the maximum power allowed on my experimental license.

I recently learned that Borut S50B located in Vipava, Slovenia heard the WM2XCS CW beacon on 40.685 MHz on 13 June 2022 at 2054 UTC RST 539."

WM2XCS/B currently operates daily from 1000 to 0300 UTC.

You can send reception reports to

I will reply via postal mail with my unique WM2XCS QSL card. Indicate in your reception report the date, UTC time, frequency, RST report, mode and any remarks.

If you hear me in QSO with another authorized 8m station, please indicate the call sign of that station I was in QSO with. As 8m propagation allows I will be looking to have CW and SSB QSOs with stations in Ireland, Slovenia and South Africa who currently are allowed to operate on 8m.

I also encouraged reception of WM2XCS/B or WM2XCS to be spotted on DXMAPS which lists 40 MHz reception reports."

George hopes that the FCC might allocate an 8 meter segment for radio amateurs, but there may be objections from operators of a nationwide network of automated high elevation stations that use meteor scatter to report mountain snow pack data.

See for some surprising history of amateur radio on 8 meters.

Space Weather Woman Dr. Tamitha Skov, WX6SWW reports:

Send your tips, reports, observations, questions and comments to

For more information concerning shortwave radio propagation, see and the ARRL Technical Information Service at For an explanation of numbers used in this bulletin, see

An archive of past propagation bulletins is at More good information and tutorials on propagation are at .

Instructions for starting or ending email distribution of ARRL bulletins are at .

Sunspot numbers for July 14 through 20, 2022 were 133, 141, 153, 166, 125, 114, and 129, with a mean of 137.3. 10.7 cm flux was 169, 171.4, 176.2, 161.2, 149.4, 144.1, and 132.2, with a mean of 157.6. Estimated planetary A indices were 5, 8, 7, 5, 8, 26, and 7, with a mean of 9.4. Middle latitude A index was 5, 7, 9, 6, 10, 19, and 7,with a mean of 9. (