venerdì 31 gennaio 2020

The K7RA Solar Update

This week we finally saw the return of sunspots, over seven of the last eight days, January 24-30. Average daily sunspot numbers rose from zero to 11.1, while average daily solar flux jumped from 71.2 to 72.9.

Geomagnetic indicators remained very quiet, signaling continued great conditions on 160 and 80 meters.

Predicted solar flux over the next month and a half is 74 on January 31 through February 2, 70 on February 3-6, 71 on February 7-13, 72 on February 14-20, 73 on February 21-22, 74 on February 23-29, 72 on March 1-3, 71 on March 4-11, and 72 on March 12-15.

Predicted planetary A index is 8 on January 31, 5 on February 1-4, 10 on February 5-6, 5 on February 7-24, 10 on February 25-26, 5 on February 27-29, 8 on March 1-3, and 5 on March 4-15.

On January 27, 2020 the total sunspot area was 100 millionth of the visible solar disc. The total sunspot area hasn’t been larger or even near that size since May 18, 2019 when the area was 140 millionth.


Geomagnetic activity forecast for the period January 31 to February 26, 2020 from F.K. Janda, OK1HH and the Czech Propagation Interest group. OK1HH has been making these reports for 42 years, since January 1978.

Geomagnetic field will be:
quiet on: February 8-9, 15-16, 20-23
quiet to unsettled on: February 3, 10-11, 14, 18-19, 24
quiet to active on: (January 31, February 1-2, 6-7, 13, 26)
unsettled to active on: (February 4-5, 12, 17, 25)
active to disturbed: no predicted disturbances.

Solar wind will intensify on: January 31, February 1 (-3,) 6-7, 12-15, (16,) 18-20, (21-22,) 26.

Parenthesis means lower probability of activity enhancement.
The predictability of changes is lower again.

Thanks to all who sent in this, a link to the highest resolution images of the Sun ever recorded: https://bit.ly/2tSr1P6

David Moore sent this link: "A 'great' space weather super-storm large enough to cause significant disruption to our electronic and networked systems occurred on average once in every 25 years according to a new study." https://www.sciencedaily.com/releases/2020/01/200129104745.htm

Rich Zwirko, K1HTV, wrote: "This winter season has been very good one for morning DXing here in Virginia on 160 meters. In the past 2 weeks, I have worked 12 different stations in Japan on FT8 on the Topband. Running only 75 W, 8 of the 12 contacts with Japan were made after my local sunrise, some as late as 30 minutes past sunrise. Some Japanese stations were decoded more than 40 minutes after the Sun had risen. Many days with the K index at 0 or 1 is making for a very stable path through the magnetic north polar region to the Orient.

“Activity on the higher bands have been made more interesting with a number of maritime mobile stations now working the FT8 mode. Stations traveling through many of the world's water grids and signing /MM at the end of their calls include DD6AJ, HA3FOK, R0LER, UR7FM, UT1FG, UW5EJX and YU2AX.

"Even with the Solar Flux Index in the low 70's, the 15-meter band has been open daily for FT8 contacts with stations in South America and a few in western Africa. The 17-meter band has been open daily to Europe, Africa, South Americas and there have also been a few openings to Australia and New Zealand stations.

"I'm looking forward to the summer months, hoping for a good 6-meter DX season."

Solar orbiter launches next week: https://bit.ly/38MfKhY

On January 24, Jon Pollock, K0ZN, in De Soto, Kansas wrote: "Friday night, January 17, there was some extraordinary propagation on 80-meter (CW) about 0530 UTC. Europeans were very strong here in the Midwest, well over S-9 in some cases. I had just finished working an Italian station and the next station that called him, which had about an S-6 signal was in New Zealand. I listened to the entire exchange between the Italian station and the New Zealander. I have never heard anything like that before on 80 meters. Basically, 80 meters was open with good signals over the entire dark side of the planet. My antenna is an 80-meter dipole at 35 feet. This is my solar minimum and I’m accustomed to 80 and 160 meters being better at these times. Clearly, the longer skip zone when the band goes ‘long’ late at night, reduces the received noise levels."

On January 26 Jon also wrote: "I got into ham radio in 1959. I like the low bands and I see it as a great equalizer. I can't put up a big antenna on the upper bands, but many of the Big Guns can't put up a big antenna on 80 and 160, so the playing field gets leveled. I have (in terms of distance) worked some really good DX on 80 and 160 this winter with simple wire antennas. One must change bands with the sunspot cycles if you want to have fun!"

N8II wrote on January 24 from West Virginia: "In the CW OPS mini contest at 1900Z Saturday, the skip zones were very long on 40 and 20, but 15 was wide open to southern California. Fifteen meters has been pretty quiet; I heard FR4QT (peaking S7) on Reunion Island chatting with a Caribbean station (unreadable) at 1500Z on Wednesday, January 22. I did get an answer from a French station who was weak on another day at around 1445Z on 15 meters.

"Low band conditions have declined in the past 10 days, but at 0330Z 160 was in good shape to LY4A in Lithuania with a S9 signal. I also logged 4Z5IW in Israel through a North American pileup (he was S4-7).

Here is latest space weather report from Dr. Tamitha Skov, WX6SWW, from several days ago: https://youtu.be/Xuz2t0-l5NE

Recently I (K7RA) decided to try FT8 with the very crude and limited wire antenna I mentioned in ARLP051 at the recent end of last year. This is a wire of no particular length (perhaps 30 to 40 feet total) that winds around through laurel bushes in my back yard, about 4 feet above the ground, fastened to the branches with tie-wraps and fed with an antenna tuner.

I knew FT8 was a powerful weak signal mode, but I was astonished at the results on 80, 30 and 20 meters. Running low power, I was being heard all over the world. Checking pskreporter.info I was surprised to see my signal reported from central Russia on 30 meters, as well as by various Japan, New Zealand and Brazilian stations, and of course coverage all over North America. Even though I had very few 2-way contacts (which are minimal anyway in FT8), just seeing where my pipsqueak signal was propagating was quite a revelation.

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 January 23 through 29, 2020 were 0, 12, 14, 18, 12, 11, and 11, with a mean of 11.1. 10.7 cm flux was 70.8, 71, 72.7, 74.7, 72.9, 74.2, and 74.3, with a mean of 72.9. Estimated planetary A indices were 5, 3, 3, 4, 3, 5, and 9, with a mean of 4.6. Middle latitude A index was 3, 1, 3, 2, 2, 4, and 6, with a mean of 3. (www.arrl.org)