giovedì 20 febbraio 2020

The K7RA Solar Update

The most recent sunspot appearance was on February 1, nearly three weeks ago.

Average daily solar flux over the past week declined just barely from 71.1 to 70.9.

Average daily planetary A index changed from 8.3 to 7, and mid-latitude A index went from 6.7 to 5.1. Solar activity remains very low.

Predicted solar flux is projected to remain very low, at 70 on February 20-27, and 71 on February 28 through April 4.

Predicted planetary A index is 18, 10 and 8 on February 20-22, 5 on February 23-25, then 8 and 12 on February 26-27, 5 on February 28 through March 3, then 20, 15 and 8 on March 4-6, 5 on March 7-14, then 10, 8, 10, 8 and 5 on March 15-19, then 10, 8, 5, 8, 12 and 10 on March 20-25, 5 on March 26-30, 20 on March 31, and 15, 8, 5 and 5 on April 1-4.

Geomagnetic activity forecast for the period February 21 to March 18, 2020 from F.K. Janda, OK1HH.

Geomagnetic field will be
Quiet on: February 22-23, March 1-4
Quiet to unsettled on: February 21, March 1-2, 8, 11-13, 15, 18
Quiet to active on: March 3, 6-7, 9-10
Unsettled to active on: February 25, 27, (29,) March 4-5, (16-17)
Active to disturbed: nothing predicted

Solar wind will intensify on February (14-15, 18-20, 27,) 28 (-29), March (3,) 4-5, (6-10,) 11

Parenthesis means lower probability of activity enhancement.

Check out the new Eclectic Tech ARRL podcast, the most recent of which (February 13) has insights from K9LA regarding solar cycle progress and effects on HF propagation:

Ken, N4TUT, in Florida (EL98gp) reported: “Had a nice opening on 10 meters on February 18 from 1900z to 2150z to the south, working Brazil, Curacao, Martinique, Peru, Guadeloupe, and Chile. I also heard the DX stations working Georgia, South Carolina, North Carolina, Virginia, and West Virginia. I worked one WM6 in California off back corner of my beam.”

Ken didn’t give an indication of which modes he used. CW? SSB? Perhaps these were all FT8.

Jon Jones, N0JK, in Kansas wrote on February 18: "Saturday was very slow on 10 meters in the ARRL International DX CW contest with almost no spots and few contacts reported by contestants. This wasn’t surprising with a sunspot number of zero and the solar flux of 71.

”But on Sunday 10 meters popped open!

“I was surprised to find the band open to the Caribbean Sunday morning. ZF1A was coming in with a 559 signal at 1725z. I called a bunch of times, but no contact. I also heard 8P5A in and out of the noise, but no luck in terms of making contact. K0AP, who is also in Kansas, managed to snag ZF1A for his only 10-meter contact in the contest. Dragan runs a Hex Beam antenna and an ACOM amplifier. My 5 watts with the 1/4 wave whip antenna were not enough this time.

“It was nice to hear some DX signals on 10 meters during the contest. The opening appeared to me to be sporadic-E. F2 propagation on 10 meters is normally loud. These signals were not with considerable fading. The Cayman Islands are also pretty close to Kansas for making direct F2 contacts on 10, but they are within double-hop Es range. Stations within one-hop Es range of the DX stations in the southeast US did much better.

“After striking out on 10, I dropped down to 15 meters and heard many very loud Central America and Caribbean stations. I worked a very loud V47T at 1829z on 21.026 MHz. This was with the 1/4 wave 10-meter whip and no tuner, so power was probably a watt or so."

Ken Brown, N4SO reported on February 18: "There is a world-wide group of users of 28 MHz on all modes, found and reported on DXSUMMIT 28 MHZ filtered at this web address: I am one of dozens of daily users.

“I find the band usually opens at approximately 12 Noon locally, 1800 UTC, and closes either before sundown, or near sundown, or 0000 UTC.

On FT8, for example . . .

KC3OL 28074.0 N4SO 21:18 17 Feb EM28IX<ES>EM50TK United States

Yesterday I worked and logged FT8 stations including PU2USK in Brazil, CX4CD in Uruguay, and CA3SOC in Chile. I did not copy or work any CW stations.”

Here is the latest video from WX6SWW:

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Sunspot numbers for February 13 through 19, 2020 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm flux was 71.2, 71.3, 70.6, 70.5, 70.7, 71, and 71, with a mean of 70.9. Estimated planetary A indices were 3, 3, 5, 3, 7, 14, and 14, with a mean of 7. Middle latitude A index was 1, 3, 4, 2, 5, 11, and 10, with a mean of 5.1. (