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ARRL Propagation Bulletin ARLP042 (2017)

ARLP042 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 42  ARLP042
From Tad Cook, K7RA
Seattle, WA  October 20, 2017
To all radio amateurs 

ARLP042 Propagation de K7RA

The past reporting week (October 12-18) saw very little solar
activity, with a sunspot number of 12 on October 15, meaning the
average daily sunspot number was only 1.7, down from the already low
average of 8.4 over the previous seven days.

Over the same two periods, average daily solar flux declined from
76.8 to 70.5, while average daily planetary A index increased from
8.9 to 21.1 and average mid-latitude A index went from 8 to 16.7.

Dr. Tamitha Skov says there are sunspots just beyond the solar
horizon which should soon come into view and begin to affect Earth:

Predicted solar flux over the near term is 74, 78 and 82 on October
20-22, 86 on October 23-26, 72 on October 27 through November 2, 70
on November 3-14, 72 on November 15-29, then 70 on November 30
through December 3.

Predicted planetary A index is 8 on October 20-21, then 10, 5, 35
and 45 on October 22-25, 15 on October 26-27, then 10, 8, 5 and 5 on
October 28-31, then 8 and 10 on November 1-2, 5 on November 3-6,
then 28, 30, 40, 28, 26, 18 and 10 on November 7-13, then 12 on
November 14-15, 8 on November 16-18, then 5, 35 and 45 on November
19-21, 15 on November 22-23, then 10 and 8 on November 24-25, 5 on
November 26-27, then 8 and 10 on November 28-29, and 5 on November
30 through December 3.

Geomagnetic activity forecast for the period October 20 to November
15, 2017 from F.K. Janda, OK1HH.

"Geomagnetic field will be:
Quiet on October 20, 30-31, November (19)
Quiet to unsettled on October 22, 28-29, November 1-6, 13-15
Quiet to active on October 21, 23-27, November 7, 9-12
Active to disturbed on November 8

"Amplifications of the solar wind, mostly from coronal holes, are
expected on October (22, 24,) 25-26, November 7-12

- Amplifications of the solar wind-prediction is less reliable at present.
- Parenthesis means lower probability of activity enhancement and/or
lower reliability of prediction."

Jeff, N8II of Shepherdstown, West Virginia wrote on October 13:

"Punk conditions with K as high as 6 and almost always at least 4
last 3 days, but heard VU7T Lakshadweep Island around 2000z with
S5-7 signal and worked Spain and Gibraltar on 15 CW in the morning
on Oct. 12. Today many EU we readable calling 3C0L, Annobon Island,
Africa on 20 CW today who was S9 and I did work (a huge pile up)."

On October 19 Jeff wrote:

"Surprisingly with the SFI running 69-72 recently, 15 meters has
been open to at least southern Europe the past 4 days. I have also
worked Reunion Island, FR4QK on October 11 and heard 9J2BO in Zambia
on 15 CW a few days. Two ops from Lithuania have been doing an
outstanding job of decreasing worldwide demand for Annobon Island
off the west coast of Africa operating as 3C0L.

"They had a good signal on all bands 160 through 12 meters here and
I have made QSOs with them on all HF bands except 40, 30, and 10M.
They were very good copy on 160M throughout the evening here both
Oct 16 and 18. They were S9+20-25 dB on 15M SSB on October 18 around
2100z and easily working to the west coast. Conditions on 15 have
also been good to the Middle East around 1300-1500z most days with
recent QSOs with Israel, Lebanon, Saudi Arabia, United Arab
Emirates, and Qatar."

K2CHM from Framingham, Massachusetts wrote on October 13:

"Much to my surprise and pleasure I worked ZD7FT on St Helena Island
SSB at 1950 UTC October 11 on 28.489.  My QTH is FN42 in eastern
Massachusetts and I am only running 60 watts to a dipole about 20'
off the ground."

David Moore sent this:

Jon Jones, N0JK in Kansas sent these notes on October 16:

"Sporadic-E is rare in October, the only month of the year with less
is March. Any Es in October is a Halloween treat.

"There has been sporadic-E on 6 Friday 10/13, Saturday 10/14 and
Sunday 10/15 this weekend. Perhaps associated with the high
geomagnetic activity. Sunday was probably the best.

"From work, I logged KM4SEG EL88 at 1648z October 15 on SSB 50.145
MHz. I was using the old MFJ-9406 10W and a 1/4 wave mag mount whip.
Solid contact and received a 5x5 - 5x7 report. Heard but didn't work
AE2DX. Saw Florida stations had Es from 1500z to after 1900z to

"Most activity initially old school CW and SSB. Later some on the new
FT8 mode.

"That afternoon - the Es - TEP link path opened from New England to
CE and LU.

"LU5FF       2206Z  50105.2 FF99 FN42 599                   NK1K     
LU5FF        2206Z  50105.2 FF99>FN42 599                  NK1K     
LU5FF        2202Z  50105.0 s5 FN44 MAINE                   K1TOL  

"Both CW and FT8 QSOs were logged.  Great to see some F-layer DX this
late in the solar cycle.

"More 6 meter sporadic-E on October 16.

"KD4ESV in Florida spotted the HI8W/b and some domestic station

"KD4ESV      1811Z  50125.0 EM57ESEL87RL                  WA4Q     
K8TV         1809Z  50125.0 EN81 EL87 58 52                 KD4ESV   
W3DOG/b      1802Z  50071.0 469 QSB IN (LOWER ALABAMA)      WB4JPG   
W4IMD        1759Z  50125.0                                 K1TTT    
N9RD         1757Z  50125.0 EN61 EL87 57                    KD4ESV    

"More 50 MHz activity:

"Some weak Es October 16 allowed links to TEP. I heard LU5FF on .105 CW
and had audible tones on CE2AWW around 2300z. Es - link to TEP.

"CE2AWW worked stations from W1, W2, W4, W5 west to California. K5CM
EM25 had CE2AWW S9+ at 2352z.

"Both LU5FF and CE2AWW operated CW and FT8."

Another piece on Hisako Koyama:

There is an Athens Astronomical Association in Athens, Georgia and
Athens Astronomical Society in Athens, Ohio, but I believe this is
the Ohio organization:

Looks like a useful event of interest to Sun watchers.

If you would like to make a comment or have a tip for our readers,
email the author at

For more information concerning radio propagation, see the ARRL
Technical Information Service web page 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

Monthly propagation charts between four USA regions and twelve
overseas locations are at

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

Sunspot numbers for October 12 through 18, 2017 were 0, 0, 0, 12, 0,
0, and 0, with a mean of 8.4. 10.7 cm flux was 70.2, 69.7, 69, 70.3,
70.9, 70.3, and 73.2, with a mean of 76.8. Estimated planetary A
indices were 29, 42, 31, 26, 9, 6, and 5, with a mean of 8.9.
Estimated mid-latitude A indices were 20, 26, 26, 31, 6, 4, and 4,
with a mean of 8.


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