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ARRL Propagation Bulletin ARLP048 (2010)

ARLP048 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 48  ARLP048
From Tad Cook, K7RA
Seattle, WA  December 3, 2010
To all radio amateurs 

ARLP048 Propagation de K7RA

Average daily sunspot numbers for the week November 25 to December 1
increased only slightly from the previous seven days, 1.3 points to
25.9.  Average daily solar flux rose 1.8 points to 80.9.

Predicted solar flux values from NOAA/USAF for the next ten days,
December 3-12, are 90, 90, 90, 88, 88, 86, 86, 85, 85 and 88.
Predicted planetary A index is 10, 8, and 7 for December 3-5, 5 on
December 6-10, and 7 on December 11-12.  There is a possibility of
geomagnetic activity today, December 3, caused by a possible coronal
mass ejection.

Geophysical Institute Prague predicts unsettled conditions on
December 3-4, quiet December 5-6, unsettled December 7-8, and quiet
to unsettled December 9.

Average daily sunspot numbers for the month of November were 36.2,
an increase of 1.2 points over October.  Average monthly values for
June through November were 18, 23.1, 28.2, 35.7, 35 and 36.2.

We now know the average daily sunspot number for the past three
months, centered on October, and it is 35.6, up about 2.6 points
from the three month period centered on September.  So the
three-month moving average, centered on May through October was
16.2, 20.4, 23.2, 28.9, 33 and 35.6.  Because it is a moving
average, with one month increments, the average centered on
September includes all the data from August 1 through October 31,
and the latest centered on October includes daily sunspot numbers
from September 1 through November 30.  A more precise reading of the
difference between the non-rounded October-centered and the
September-centered averages is 2.67 points.

The solar cycle continues to show improvement, but at a very slow

Robert Elek, W3HKK of Johnstown, Ohio reported good conditions for
last week's CQ World Wide CW DX Contest.  He wanted to see what he
could do with 100 watts and simple antennas on 40, 15 and 10 meters,
and with some casual contest operating he worked 200 stations in 31

He was eager to check out a new antenna he built, a 40 meter phased
array with two quarter wave verticals spaced a quarter wavelength
apart, and 12 ground radials each.  He used this on 40 and 15
meters, and a ground plane on 10 meters.  On Friday night he had
problems with QRM.  The bands were packed with strong signals.

He reports that he "got up around 4:30 AM Saturday morning and heard
much more manageable QRM levels, and good signals from the
equatorial regions - Africa, The Caribbean and the Pacific. As we
approached sunrise and for a few hours after sunrise there were
scattered strong signals including ZL8X and a half dozen Hawaiian
stations, but only a few JAs or anything over the pole from Asia.
However, northern Europe (OY, OH0, TF, SM) were coming through well
past OUR daybreak.

"This time I was concentrating on seeing what I could do with my new
40 meter Phased Array by chasing rarer and long haul DX, and trying
to work as many CQ zones as I could, but not concentrating on
rates/QSO numbers.  It was a casual weekend of DXing for me.

"I checked 15 and 10 meters and heard good signals, so I spent some
time between 10 AM and 4 PM working the interesting strong ones with
my 40 meter phased array on 15 and a simple ground plane on 10m.  To
my surprise, if I heard the DX station well, I could work them, no
matter where they were. Lots of tropical Africans, some Europeans,
the Caribbean and South America were coming in 59+.

"Back to 40 early Saturday evening saw significantly improved
conditions, with tons of Euros coming through. The amazing
multiplication of 40 meter Yagis seemingly filled the band with Big
Signals from both sides of the pond, South America, and Africa.  I
again decided to sleep early and get up around 3 AM Sunday to look
for Asia and the Pacific, rather than battle it out with the
multitudes.  Sunday morning, polar conditions were still not good,
but more JAs were coming through. I heard about a dozen, some with
signals around 599 for a time but most were 559 or so.  I heard one
Guam station, perhaps 8 VKs/ZLs, and again a smattering of JAs, but
no Indian, Chinese or other Asian stations in my casual strolls up
and down the band. Pacific and northern European stations continued
to come in several hours past sunrise, and some up till around 11 AM
local time (northern Europe and northern Russia).

Sunday from 11 AM till 4 PM, working 10 and 15 was a ball! Not a ton
of signals, but plenty to choose from, and about half were desirable
DX, including ZD9, ZD8, Gambia, Morocco, South Africa, VQ9, 5R8,
ZL8X, ZL7 (Kermadec).  Plus many South Americans, especially LU, CX,
PY and YV, and numerous Caribbean stations.  It was a ball being
able to work nearly everything I heard with my simple antennas. You
gotta love CW for that!

"On Sunday at 4 PM I moved back to 40 and it sounded like 20 does
during contests!  599 DX galore in the afternoon Ohio sunshine.
First the Euros were coming in from 7.000 to 7.105.  Then stations
in Bulgaria, Romania, Georgia, Cyprus, Lebanon, followed by tropical
Africa, the Caribbean, South America all with much better signals.
Sure, there is less QRM as more operators drop out, but you can
really cherry pick some nice DX if you poke through the rubble on 40
on the last day of a contest."

Dave Deatrick, WA8OLD way up in Sault Ste Marie, Michigan had a
similar experience on 40 meters on Sunday, running 400 watts CW into
an inverted vee with the apex at the top of his roof.  He was amazed
that European stations were coming in strong before his local
sunset.  He also worked an Australian before 9 AM local time on
Sunday morning.

In the 1300z hour he worked Iceland, Finland, Bahamas and Australia.
In the 2100z hour it was Slovenia, Croatia, Poland, Sicily and
Serbia.  In the 2200z hour it was Netherlands, Sweden, Cyprus and
Portugal, and during the 2300z hour he worked Turkmenistan, France
and Bulgaria.

Jon Jones, N0JK in Wichita, Kansas reports that on November 29 at
0225z he worked W4IMD in EM84 on 6 meter E-skip.  Later he heard the
XE2K beacon for over 30 minutes around 0335z on 50.015 MHz.  For
some images of what W4IMD was using, check

Mike Carter, K8CN of Durham, New Hampshire wrote, "As a relative
newcomer to QRP contesting (about 3 years experience now) and
without a substantial history of contesting at any higher power
level, I was intrigued by the unusually good propagation we
experienced in CQWW CW last weekend. Many QRP contesters established
new personal records for this contest. Apparently I was not the only
one who noticed - the 3830 contest reflector has many comments on
the good propagation enjoyed by all.  My friend Mark, K1RX, a highly
accomplished Single Op contester with a very nice antenna farm,
commented that the propagation conditions were the best he'd seen
for this particular contest in 20 years of participation, but then
propagation is always good for a station with 1500 watts into
stacked Yagis!"

Dick Bingham, W7WKR of Stehekin, Washington (a little village in the
mountains completely off the grid, and reachable only by boat) sends
along some info about Long Delayed Echoes (LDE) from  At are
recordings made by DK6NP of supposed LDEs on 40 meters with a 46
second delay, but I had difficulty hearing exactly what was going on
in those recordings. offered a couple of
interesting LDE links, at and

Check out this page on the Ionosphere Program at the National
Geophysical Data Center:

Dean Straw, N6BV sent along a useful link for web-based seminars
from the Northern California Contest Club, at  At the bottom are a couple of his
presentations on propagation, complete with audio.

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 the
numbers used in this bulletin, see An archive of past
propagation bulletins is at  Find more good
information and tutorials on propagation 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 November 25 through December 1 were 22, 23, 22,
34, 31, 24, and 25, with a mean of 25.9. 10.7 cm flux was 77.9,
76.2, 76.5, 80.1, 82.5, 86.4 and 86.5 with a mean of 80.9. Estimated
planetary A indices were 4, 2, 12, 6, 3, 3 and 2 with a mean of 4.6.
Estimated mid-latitude A indices were 2, 0, 5, 7, 2, 2 and 1 with a
mean of 2.7.


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