Propagation Forecast Bulletin #26 de K7RA:
W1AW Bulletin via the ARRL
June 28, 2013
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Propagation Forecast Bulletin #26 de K7RA:
QST de W1AW
Propagation Forecast Bulletin 26 ARLP026
>From Tad Cook, K7RA
Seattle, WA June 28, 2013
To all radio amateurs
SB PROP ARL ARLP026
ARLP026 Propagation de K7RA
Conditions were good for Field Day weekend last week. Only
unsettled geomagnetic conditions (even quiet at times) affected us,
no big flares or geomagnetic storms, and sunspot numbers also
cooperated by peaking at 135 and 137 on Friday and Saturday.
Geomagnetic instability was caused by a brisk solar wind, which was
over by June 24.
At K7RA I used the ARRL Field Day Locator map at
http://www.arrl.org/field-day-locator to contact a few club groups
earlier in the week to see if they could use another CW operator.
I've found in years past that with so many newer licensees who were
not required to learn Morse code, that CW ops can be in demand at
some sites. Not only are CW operators wanted at many Field Day
locations, but the newer licensees are fascinated to see Morse code
in action. I really don't think that some of us old-timers who worry
about some imagined demise of CW have much to worry about.
At the last minute I changed my mind and decided to drag some gear
accumulated over the past decade but never put on the air, and
operate Class 1C, mobile single operator. Everything was last
minute, including the antenna installation and power connections,
with the radio sitting between the dashboard and the windshield.
The antenna was a very heavy kilowatt-rated screwdriver type
antenna, about 20 pounds excluding any mounting hardware or a whip,
although I swore it weighed twice as much. The plan was to mount it
on a very heavy duty magnetic mount on the roof, perhaps with guying
(this is not recommended by the manufacturer), but during assembly I
discovered this would not work, as the mounting was not compatible
with the antenna. So instead, during a fit of hacker improvisation,
I leaned the heavy screwdriver assembly out the right-rear passenger
window, (resting on the seat), and rolled up the window as far as I
could to hold it in place. I cut the coax with PL-259 off the
magmount, stripped back the other end, and attached the center wire
to the base of the antenna.
The next surprise was that although I had a 7 foot whip, I lacked
the adaptor that would screw into the top of the antenna assembly.
So what to do? Just stick it in the hole, let it roll around, and
pray. I now had an antenna (of sorts) leaning out the right rear of
my old car, about 35 degrees above horizontal, at best.
To hook the DC cable from the radio to the car battery, I needed to
go through the firewall below the dashboard. Despite finding
diagrams and advice specific to my 13-year-old car model online, I
could not get the cable through. So I grabbed one of those portable
starter batteries (fully charged), put it on the front passenger
seat, and duct-taped the massive car battery connection clips (which
are like jumper cables) to the DC cable from the radio, and another
12 VDC pair to the antenna tuning motor. In addition, to keep the
battery charged, I tied in a very flimsy looking 12 VDC lighter plug
in parallel with the whole mess, and plugged it into the dashboard
lighter socket. This connector with wire was still in the bubble
pack in my junk box after 20 years or more.
To finish it all off, I ran a couple of long counterpoise wires from
the base of the antenna, out the rear doors and along the ground,
attaching them to the coax shield broken out at the base of the
antenna. I ran a heavy wire from the ground lug on the radio to a
metal screw beneath the dashboard that seemed good for ground, at
least at DC.
The whole thing worked, at least on 80 and 20 meters. 15 meters was
marginal, and 40 meters I could not tune at all. Starting late
Saturday evening, operating both SSB and CW, I lasted until about
1730 UTC Sunday morning. Most of the operation was from a local
Seattle cemetery, on a nearby hilltop overlooking Lake Washington,
east of the University of Washington. Very quiet, with power lines
far away at the perimeter.
Back to solar activity, from the previous week, average daily
sunspot numbers were up nearly 13 points to 109.7, and average daily
solar flux rose nearly 7 points to 122. Geomagnetic activity was
greater than the previous week, with average daily planetary A index
rising from 4.3 to 12, and average mid-latitude A index rising from
4.9 to 11.9.
Ideally we would like to see the solar flux and sunspot numbers as
high as possible, and the A index low, at least for 40 through 10
meters. On 160 meters we would like to see sunspot numbers low as
well. I hear lots of complaints about this weird, weak solar cycle,
but the 160 meter operators have absolutely no problem with the low
Yesterday on Thursday, June 27 the solar flux dipped below 100 to
99.5, which is below the average for the previous seven days (122).
Nothing significant about 100, it is just one of those nice round
numbers, like when your odometer reaches 100,000 miles, or the
atmospheric carbon dioxide reaches 400 ppm at Mauna Loa.
The 99.5 flux number is directly from the observatory in Penticton,
British Columbia, but the NOAA site shows it at a nice round value
of 100 (see
http://www.swpc.noaa.gov/ftpdir/latest/DSD.txt). This is
because NOAA has always reported this value in whole numbers,
similar to the way the press reported recently that atmospheric
carbon dioxide reached 400 ppm. The actual average value for the
month of May was 399.77 ppm, but for all practical purposes you
could say that it is 400 ppm, just as solar flux was 100. Any
differences are very small.
The most recent prediction (Thursday, June 27, 2013 by forecasters
Carr and Lash) from NOAA/USAF has 10.7 cm solar flux at 100 and 105
on June 28-29, 110 on June 30 through July 2, 105 and 100 on July
3-4, 100 on July 5-7, 115 and 120 on July 8-9, 125 on July 10-13,
and 120 on July 14-16. Flux values then reach another peak of 130 on
>From the same forecast, planetary A index (which was 8 on Thursday,
below the average of 12 for the previous seven days) is 17 and 9 on
June 28 and 29, 5 on June 30 and July 1, then 7, 10 and 7 on July
2-4, 10 on July 5 and 6, 5 on July 7-16, 10 on July 17, 15 on July
18-20, then 18, 10 and 8 on July 21-23, and 15 on July 24 and 25. It
looks like some unsettled geomagnetic conditions are in the forecast
You can check for daily updates on this forecast out to 45 days
http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html. A new
daily forecast generally appears some time after 2100 UTC daily.
Just received before release on early Friday morning,
spaceweather.com reports earth-directed solar flares from sunspot
groups 1777 and 1778. The two flares were C-class, and the CME could
deliver a glancing blow to our Earth.
F.K. Janda, OK1HH believes that the geomagnetic field will be active
to disturbed on June 28, quiet to unsettled June 29 through July 1,
quiet on July 2, quiet to active July 3, active to disturbed July 4,
mostly quiet July 5 and 6, quiet to unsettled July 7, mostly quiet
July 8 and 9, quiet July 10-15, mostly quiet July 16 and 17, quiet
to active July 18, mostly quiet July 19, active to disturbed July
20, and quiet to active July 21 and 22.
NOAA has a projection for the rest of the solar cycle, updated
monthly, showing predicted smoothed sunspot numbers resolved to
one-tenth, instead of whole numbers. The smoothing is a 13-month
moving average, centered on any month of interest. Sunspot numbers
are always whole numbers, so the resolution to one-tenth is an
artifact of the averaging or smoothing process.
For any current month, the number represents an average of the
previous 6 months plus the current month plus the predicted values
for each of the next 6 months. The first and last months in the
calculation are factored in at 0.5.
Before the last day of June 2013, the smoothed sunspot number for
February 2013 represents 10 months of known values and 3 months of
predicted values, June through August 2013. These are based on the
reported numbers from the Sunspot Index Data Center in Belgium.
These numbers are always lower then the Boulder sunspot numbers,
which are recorded at the bottom of each bulletin and in our own
3-month moving average, reported here monthly.
The predicted average sunspot numbers for March, 2013 through July
2014 are 67.5, 70.1, 72.7, 75.7, 78.6, 81.6, 84.7, 86.3, 86.9, 86.7,
86.4, 85.6, 84.7, 83.7, 82.6, 81.4 and 80.2. Note that the peak is
centered on November 2013, or perhaps October 2013 through January
2014 to broaden the scope and hedge our bets. A similar prediction
for monthly smoothed solar flux tracks this very closely, also
peaking in November 2013. Let's see how this looks after the
beginning of the new month.
Jeff Hartley, N8II of Shepherdstown, West Virginia is in grid square
FM19cj, about three miles southwest and across the Potomac River
from the Antietam National Battlefield, which is actually in
On June 26 Jeff wrote: "This summer on HF at least below 12 meters
has been one of the most interesting and exciting periods I can
remember, despite the lackluster solar activity. Many nights 17
meters is open until midnight local time to southeast and northern
Europe and, 15 is often open to Asia and Europe around 0200-0400
After years of disappointment, the All Asia DX contest June 15-16
had above average conditions on 15 meters for most of the weekend.
Just on 15 meters, I worked just short of 200 Asian stations with
106 prefixes in a part-time effort.
Saturday morning around 1200 UTC was a losing battle against the
European stations into all parts of Asia. Saturday afternoon I
returned after a long break at 2045 UTC to find very loud JA's who
stayed loud until 2230 UTC, then gradually faded down until not many
were audible by 0130 UTC. Sunday around 1200 UTC only JO3JIS had a
good signal here from Japan; he was the most consistently loud JA
here. A few signals from Central Asia were loud, such as UN/UP's.
Around 1350 UTC I returned to loud signals from all of Asia
including Japan, which is fairly rare for this QTH, but had occurred
several times the week before. Activity between Europe calling CQ
and Asians extended from 21.0 to 21.07 MHz! I don't think JA ever
faded out completely all afternoon, but signals weakened about 1545
UTC. Our toughest area, Southeast Asia around 1500 UTC was quite
loud, working three 9V1's with 9V1YC over S9! XW0YJY was heard, but
I could not break thru the European pile-up. All total, I worked 58
Japanese prefixes and 19 from Asiatic Russia where activity was
somewhat less than expected.
Almost every night, there is a good 20 meter opening to western Asia
and Europe/Russia/Ukraine and Scandinavia from 0200-0400 UTC. Some
of the DX worked late in the evening here include on June 11
FK8DD/M, ES5, ER3, UY5, OM3, then on 15 meters RA3TO/P and IZ7. On
June 13, RV9CPB/9 on 17. June 14 featured ES3, EU7, and SM0 on 17
meter phone followed by on 15 meters, SM6, YL2, R4, RX4, RV9, RM5,
HA8, UA6, UA4, UR4, R8, RZ6, UT9, UR0, and UA3T ending at 0312 UTC.
The sporadic E season on 6 meters has been disappointing. I missed
European openings on June 13. On the June 19, W6XK in CM97 and N6JK
in CM98 were logged on 6 meter CW around 0230 UTC. Finally, on June
23 and 24 we had a good opening to South America and Mexico, all
multi-hop Es. At 2102 UTC, I worked PV8ADI with a S7 signal, the
first ever Brazilian for me on Es; he stayed in for an amazing 2
hours plus longer! Then, 9Y4VU was found on SSB at 2107. YV1 was
also heard along with VP2V. CO2WF was logged at 2304. Between 2331
UTC and 0039 UTC, five XEs over a wide area were worked mostly in
XE2, good for some new grids. On June 24, PV8 was heard again with
FM5WD being logged at 2224 UTC."
Thanks, Jeff! He mentions years of disappointment regarding working
Asia, but here where I am on the West Coast, this is not a problem.
This is just like Europe being easy to work from the East Coast.
For more information concerning radio propagation, see the ARRL
Technical Information Service at
http://arrl.org/propagation-of-rf-signals. For an explanation of the
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
Monthly propagation charts between four USA regions and twelve
overseas locations are at
Sunspot numbers for June 20 through 26 were 128, 135, 137, 118, 82,
91, and 77, with a mean of 109.7. 10.7 cm flux was 126.3, 133.2,
130, 128.2, 120.6, 109.2, and 106.5, with a mean of 122. Estimated
planetary A indices were 11, 17, 14, 15, 15, 8, and 4, with a mean
of 12. Estimated mid-latitude A indices were 12, 17, 13, 16, 14, 9,
and 2, with a mean of 11.9.
Source: W1AW Bulletin via the ARRL.
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Propagation Forecast Bulletin #26 de K7RA:
by VA7KX on June 30, 2013
Mail this to a friend!
very well presented. *I particularly enjoyed the dx worked to compare with my on air experience. keep up the good work.
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