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The K7RA Solar Update

04/17/2020

Sunspots are gone again. We are at the bottom of the solar cycle, so conditions should only get better. There is an increase in on-air activity due to the large number of people staying at home because of Covid-19, and this week we seem to be overwhelmed with reports of sporadic E openings.

The last observed sunspot disappeared on April 5, so weekly average daily sunspot numbers declined from 5.1 last week to zero this reporting week, April 9-15. Average daily solar flux went from 70.2 to 69.5.

Geomagnetic indicators remain quiet as well, with average daily estimated planetary A index going from 6.6 to 6.1, and mid-latitude numbers, sourced from a single magnetometer in Virginia, to 5 from 5.3.

Predicted solar flux is 69 on April 17-24, 70 on April 25 through May 8, 68 on May 9-20, and 70 on May 21-31.

Predicted planetary A index is 8 on April 17-18, 12 and 8 on April 19-20, 5 on April 21-25, 10 on April 26-27, 5 on April 28-29, 8 on April 30, 5 on May 1-4, then 12, 5, 8 and 8 on May 5-8, then 5 on May 9-11, 10 on May 12, 8 on May 13-16, 5 on May 17-22, 10 on May 23-24, then 5, 5 and 8 on May 25-27, and 5 on May 28-31.

Geomagnetic activity forecast for April 17 until May 12, 2020 from F.K. Janda, OK1HH:

Geomagnetic field will be
Quiet on April 20-21, May 2-3, 6
Quiet to Unsettled on April 17-18, 22-24, 28-29
Quiet to Active on (April 25, May 1, 5, 7-9, 12)
Unsettled to active on (April 19, 26-27, 30, May 4, 10-11)
Active to Disturbed: nothing!

Solar wind will intensify on April 17-19, (20,) 26-28, May 4-6, 8-10

Remarks:
- Parenthesis means lower probability of activity enhancement.
- The predictability of changes remains lower as there are no indicators.

Edgar Leighton, HI8PLE, wrote on April 11 from Dominican Republic: "The sporadic E season started very well here. There has been a great activity on 144 MHz in the Caribbean. On April 9, 2140 UTC, I worked PJ2BR and on April 11 0027 UTC worked J69DS. On the same day at 1936, I contacted 9Y4D and 9Z4D. Finally, on April 12 at 0113, I worked YY5BRB. All contacts were made using FT8 with 16 element beam and 150 watts
.

“I have noticed that the conditions with the Lesser Antilles are steady and last all day and night, then, at dusk some TEP activity on 50 MHz.”


Danny Miller, KB8W (EN57) wrote: "Yesterday, April 14, was the earliest Es/TEP activity that I have ever experienced here in EN57 (in the far NW corner of Michigan's Upper Peninsula).

"I have been active for the past 10 years on 6 meters. I looked back in my logs and find that the first Es activity of the spring season is usually in early May; in 2019 my first contact was on May 10. But I have never even heard anyone via Es in April of any year (I have made contacts via meteor scatter in all months of the year).

“Six meters opened for me at about 1710Z on April 14 when I copied CM2XM (EL83) on 50.313 MHz using FT8. Over the next 10 hours I worked 19 stations in New England, the Gulf Coast and Cuba.

"According to PSKReporter, I was heard at 2202Z by TI2CDA (EJ79) and at 2201Z by HK4GSO (FJ26). Those are the first TEP receptions that I have experienced. I was still hearing signals when I turned off the radio and went to bed at about 0400Z April 15.

“For me, a remarkable day as I run only 50 W to a 5 element Yagi."

William Herzberg, AA8WH, writes from Michigan: "Starting April 14 at about 2246 UTC, 6 meters was open on FT8. I worked NK4DX, in Fort Lauderdale. When 6 died down, I moved down to 12 meters, and worked KN4NN in Crawfordville, Florida and W9OO in Harvey, Illinois. I then moved up to 10 meters and worked WZ9B in Noble, Illinois, N4UXP in Atlanta, Georgia, NT4J in Fuquay Varina, North Carolina, and AB0S in Beloit, Kansas.

“At 0324 UTC, signal strengths were up to S7 on the peaks. I worked N5LFA in Potts Camp, Mississippi, WB4HMA in Nashville, Tennessee, N4JRS in Oakwood, Georgia, and J68HZ on St. Lucia. Ten meters continued to stay open well past 0400 UTC."

Lance Collister, W7JG, wrote from Frenchtown, Montana: "April 15 was the best 6-meter activity I have ever seen this early in the season. Unlike the eastern half of the country, out here in western Montana we normally are one or two hops away from linking into any high TEC activity and/or TEP propagation. Usually, it seems a higher Kp index is required to cause 6-meter Es openings to the south from up here. But perhaps because the Kp index had been up to 3 on both April 14 and early on April 15, plus the time of year, had something to do with it. Anyway, the 6-meter band was open from here in western Montana to the southeast for 9 hours, and I worked my first HC (Ecuador) station since I got on 6 meters 24 years ago! In addition to many domestic contacts, these DX stations were all worked on 50.313 using FT8 mode: XE1KK, XE1K, XE1EE, XE1H, TI2CDA,TG9AJR, TG9ANF, HP2DFA, HK3PJ, HC2DR, HC5VF, HC2AO, OA4DOS, LW2DAF, LU5CQC, LU2DPW, and CX6DRA.

"Normally up here, we wouldn't think a big Es opening before the end of May was possible! I am sure it helped that so many people were sequestered at home during the pandemic and able to be by their radios. This may be a once in a lifetime event, but it sure was memorable. I’m looking forward to the great 6-meter moonbounce conditions at the end of this month to pick up another all-time new one!"

Check out Lance's web page at http://www.bigskyspaces.com/w7gj/

Dave Bono, K6OAK, of Fremont, California wrote: "We are in the middle of week 5 of Stay at Home restrictions here in the San Francisco area. I thought I would use the opportunity of being home to make some improvements to my 6BTV ground mounted vertical antenna. So, I checked all my cable connections and added two 33-foot radials and a few shorter ground radials. Then I went into the shack shortly after 2200Z and fired up the Kenwood 590SG to see if there was any improvement. Listening to FT8 there were signals on all bands from 6 to 40 meters! What a difference! I worked a bunch on 10 meters in short order at under 30 watts. I wish I could say it was the radials, but I’m sure it was just a coincidence that the bands opened up after being very stingy for the prior few days and weeks!"

Mike Treister, W9NY, operates from the top of a tall building in Chicago: "To my surprise, 10 meters and 6 meters were full of stations coming in to Chicago the evenings of April 14-15. Using a non-directional poorly matched antenna (G5RV for 20 meters up 450 feet) with 100 watts on SSB I worked several stations around the country on 10 and some on 6 meters including Mexico. Can't wait for those sunspots!”

Martin McCormick, WB5AGZ, wrote: “There was a whopper of a 10-meter opening to Oklahoma on Tuesday, April 14, from around 16:30 Central Daylight Time until it all faded out near midnight. As heard from a discone about 50 feet above the ground, signals on 10 from the East Coast of the US rolled in from the New York City Area down to North Carolina with lots of different signals fading in and out over each other, which is quintessential Sporadic E behavior.

“It all appears to have started rather suddenly at about 16:45 local time. The scanner was hearing business and public safety signals from local sources and then W4BWW in East Tennessee came in out of the blue talking to a station in Kansas, which was inaudible from here, here being about 60 miles South of the Oklahoma/Kansas border. That exchange was probably on 29.6 MHz as it was FM simplex.

“The next signal was a repeater ID in North Carolina in which all one could hear was a female voice saying "North Carolina” at the end.

“After that, it was crazy-town on steroids. There was an MCW ID for a repeater in the 3rd or 4th call area that was too mutilated to read. It later turned out to be N3AUY in Maryland.

“One of the signals in for a good portion of the evening was the WA3PBD repeater in Pittsburgh, Pennsylvania. It's full MCW ID is WA3PBD/R PGH and its signal was present, though occasionally blotted out by temporarily stronger signals from other repeaters before coming back in. Another briefly heard system was the KD2WA repeater whose voice ID gives the PL tone as 110.9 Hz in a synthesized male voice.

“I did possibly hear a Florida station, but am not sure if I actually heard him on simplex or he was hitting one of the repeaters. The scanner is set to scan 29.6 through 29.680 in 20 kHz steps and the band opening was good enough to make this a very chaotic experience.

“Newcomers to amateur radio who heard this opening got to hear what 10-meter FM was like in previous sunspot maxima, even though this is the bottom of the barrel for solar activity. Sporadic E is like the Spanish Inquisition mentioned in the ‘Monty Python’ TV series in which the line ‘Nobody expects the Spanish Inquisition’ became popularized.

“Also, what anybody hearing all this chaos may not realize is that there was once a time in which the 30 to 50 MHZ band was the work-a-day band for business and public safety communications in the Americas. During the incredible Solar Maximum of 1958, hundreds of cities and small towns alike would jam each other's radio systems with full-quieting foreign traffic as they tried to do routine business. FM signals from the Boston Fire Department were full quieting in Oklahoma and surrounding states on 33.77 MHz on just about any winter day that year. Those band openings spurred the move to higher VHF and UHF frequencies where most mobile business and emergency services now live.”

 

If you would like to make a comment or have a tip for our readers, email the author at k7ra@arrl.net.

For more information concerning radio propagation, see 
http://www.arrl.org/propagation and 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 April 9 through 15, 2020 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm flux was 70.3, 69.2, 70.6, 70.8, 70.3, 68.9, and 68.4, with a mean of 69.5. Estimated planetary A indices were 5, 5, 6, 7, 5, 8, and 7, with a mean of 6.1. Middle latitude A index was 5, 4, 4, 5, 4, 7, and 6, with a mean of 5.



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