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ARRL Propagation Bulletin ARLP043 (2021)

SB PROP @ ARL $ARLP043
ARLP043 Propagation de K7RA

ZCZC AP43
QST de W1AW  
Propagation Forecast Bulletin 43  ARLP043
From Tad Cook, K7RA
Seattle, WA  October 22, 2021
To all radio amateurs 

SB PROP ARL ARLP043
ARLP043 Propagation de K7RA

Solar activity declined last week, and on one day (October 17) there
were no sunspots at all. Most days this week had the minimum
non-zero sunspot number, which is 11, indicating a single sunspot
group containing a single sunspot.

Average daily sunspot number declined from 23.7 to 11.3, and average
daily solar flux dropped seven points from 85.6 to 78.6.

Geomagnetic indicators were quiet, with average planetary A index
declining from 12.4 to 8.4, and average middle latitude A index from
10.1 to 5.4. No middle latitude A index was available for October
16-18, so middle latitude A index figures presented at the bottom of
this bulletin are uneducated guesses on my part.

Despite the lower activity, I noticed frequent 10 and 12 meter
openings here at my location in Seattle, via FT8 mode.

Predicted solar flux appears lower too, with values at 82 and 83 on
October 22-23, 84 on October 24-25, 85 on October 26-29, 88 on
October 30, 85 on October 31 through November 11, 80 on November
12-20, then 85, 90, 95 and 90 on November 21-24, 88 on November
25-26, and 85 through the end of the month.

Predicted planetary A index is 8 on October 22, 5 on October 23
through November 1, 8 on November 2, 5 on November 3-5, then 12, 10
and 8 on November 6-8, 5 on November 9-13, 12 on November 14-15, 8
on November 16-18, 5 on November 19-20, 10 on November 21, 5 on
November 22-28 and 8 on November 29.

Here's the geomagnetic activity forecast for October 22 - November
16 from F.K. Janda, OK1HH. 

"Geomagnetic field will be:
quiet on: October 27, November 3-5,
quiet to unsettled on: October 22-24, 26, 30-31, November 9,
quiet to active on: October 25, November 1, 6, 10-13,
unsettled to active on: October (28-29,) November (2,) 7-8, 14-16,
Active to disturbed: Nothing predicted.
 
"Solar wind will intensify on October (22, 25,) 27-31, November 1,
(8,) 9-10, (11).
 
"Parenthesis means lower probability of activity enhancement."

On October 21 WB8VLC in Salem, Oregon, as well as posts on the
Western Washington DX Club email list noted strong S-9 SSB signals
on 15 meters from J5T in Guinea-Bissau.

He sent an extensive list of contacts, and said, "10, 12 and 15
meters have sounded like 20 meter phone for the past month, and not
listed are many 10 and 12 meter QSOs on SSB to South America and the
Pacific that I haven't included.

"Antennas all home made: 10 meter 4el Yagi at 30 feet and dual band
12/15 Moxon at 23 feet, on 17 I use my 15/12 Moxon loaded. All QSOs
use 400 to 500 watts with home made LDMOS amp and K3S."

A short list of a few of his contacts, all times in UTC:

2021-10-19 1517 FY5KE 10m 28.019 CW  French Guiana      
2021-10-18 0032 3D2AG 12m 24.907 CW  Fiji       
2021-10-18 0016 3D2AG 10m 28.029 CW  Fiji      
2021-10-17 2143 E51JD 10m 28.430 SSB South Cook Islands   

Notes:
FY5KE - I hear him every week on 10 CW or 10 SSB since Sept 2021.
3D2AG - Antoine and I start on 10 CW then we move to 12 CW most weekends
3D2AG - ANTOINE has been on every night for the past week on 10 and 12. 
CW since mid September.
E51JD - Jim has been on every week on 10 SSB since about early September. 

N0JK in Kansas wrote: "The afternoon of October 18 sporadic-E
appeared over the east coast of North America. This allowed suitably
located stations in W3 such as NZ3M to make sporadic-E TEP contacts
to Argentina.

"The Es continued after sundown.

"In eastern Kansas, I found 6 Meters wide open after returning from
dinner with my XYL at 0010 UTC October 19. I made over a dozen FT8
contacts to W1, W2, W3, W4 and VE3. Best DX was WW1L in FN54 at over
1400 miles.

"Today October 21 is the peak of the Orionid Meteor Shower. I set up
portable and was able to work N0LL/P in rare grid DN80 at 1142 UTC
on 6 Meter meteor scatter using MSK144.

"Larry Lambert, N0LL is operating portable from rare grid DN80
during the Orionid Meteor shower on 6 Meters to help Fred Fish
Memorial Award (FFMA) enthusiasts log a new one.

"He had a strong sporadic-E opening on 6 Meters October 20, making
contacts from VE2 across the eastern states around 1600 UTC, then
west to California. His operation was planned to be primarily meteor
scatter, but rare October sporadic-E let many stations work a rare
grid square."

Yet another article concerning big solar activity and monster
flares:

https://bigthink.com/starts-with-a-bang/giant-solar-flare/

I like to check the STEREO mission for upcoming activity. I look out
for the big white splotchy images just over the eastern solar
horizon, which is on the left:

https://stereo.gsfc.nasa.gov

On October 21 Spaceweather.com noted: "A new sunspot group is
emerging over the Sun's southeastern limb. It is crackling with
activity."

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

For more information concerning shortwave radio propagation, see
http://www.arrl.org/propagation and the ARRL Technical Information
Service web page 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/.

Instructions for starting or ending email distribution of ARRL
bulletins are at http://arrl.org/bulletins .

Sunspot numbers for October 14 through 20, 2021 were 24, 11, 11, 0,
11, 11, and 11, with a mean of 11.3. 10.7 cm flux was 83.4, 84,
77.6, 77.4, 75.9, 76, and 75.9, with a mean of 78.6. Estimated
planetary A indices were 7, 6, 6, 10, 10, 14, and 6, with a mean of
8.4. Middle latitude A index was 6, 4, 3, 5, 6, 9, and 5, with a
mean of 5.4.
NNNN
/EX

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