ARRL

ARRL Propagation Bulletin ARLP020 (2014)

SB PROP @ ARL $ARLP020
ARLP020 Propagation de K7RA

ZCZC AP20
QST de W1AW  
Propagation Forecast Bulletin 20  ARLP020
From Tad Cook, K7RA
Seattle, WA  May 16, 2014
To all radio amateurs 

SB PROP ARL ARLP020
ARLP020 Propagation de K7RA

Nice numbers this week, with average daily sunspot numbers rising
from 118.4 (during May 1 to 7) to 142.4 in the past reporting week,
May 8 to 14. Average daily solar flux rose from 135.6 to 157.5.
 
The latest prediction from USAF/NOAA has solar flux values of 155
and 150 on May 16 and 17, 145 on May 18 to 20, 140 on May 21 and 22,
120 on May 23 to 26, 115 on May 27 to 29, 120 and 125 on May 30 and
31, 135 on June 1 and 2, 140 and 145 on June 3 and 4, and 150 on
June 5 to 9. Flux peaks at 165 on June 10 and 11, and hits a minimum
on June 23 to 25 at 115.
 
The latest planetary A index prediction sees a planetary A index of
7 on May 16, 5 on May 17 to 20, 8 on May 21 and 22, 5 on May 23
through June 3, 8 on June 4 to 6, 10 and 8 on June 7 and 8, then 5,
10 and 8 on June 9 to 11.
 
ARRL Field Day is now six weeks away, so those dates (June 28 and
29) are moving into the 45-day forecast window that is updated daily
by NOAA. Although this is a long way out, we see solar flux rising
from 115 on June 23 to 25, to 120 on June 26, 125 on June 27, and
135 on June 28 and 29.  Planetary A index is predicted at a nice
stable level of 5 from June 19 forward.
 
This looks like good conditions for the 2014 Field Day. The 2013
Field Day was on June 22 and 23, and last year on Friday through
Sunday (June 21 to 23) the planetary A index was 17, 14 and 15,
quite a bit more unsettled than the prediction for this year. Both
the planetary and mid-latitude numbers saw a K index of 4 over
several periods.
 
The daily sunspot numbers on June 21 to 23, 2013 were 135, 137 and
118, and daily solar flux values on those dates were 133.2, 130 and
128.2.
 
The relevant records from last year are at
http://www.swpc.noaa.gov/ftpdir/warehouse/2013/2013_DGD.txt and
http://www.swpc.noaa.gov/ftpdir/warehouse/2013/2013_DSD.txt and the
daily 45-day forecast is at
http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html .
 
44 days into the future is a long time for solar indices
predictions, but this is all we have. This forecast indicates
slightly better conditions for Field Day than we experienced last
year.
 
Every week we are fortunate to receive a geomagnetic prediction from
OK1HH in Prague, Czech Republic. This week he believes the
geomagnetic field will be quiet to active on May 16, mostly quiet
May 17 to 19, quiet to active May 20, quiet to unsettled May 21 to
26, quiet to active May 27, quiet on May 28 to 30, quiet to
unsettled May 31, active to disturbed June 1, quiet on June 2 and 3,
quiet to unsettled June 4, mostly quiet June 5 and 6, active to
disturbed June 7 and 8, mostly quiet June 9, and back to quiet on
June 10 and 11.
 
OK1HH believes that the cycle 24 peak is just behind us. He notes
that sunspot activity increased toward the end of October 2013, but
the response in the ionosphere was particularly evident later,
around the end of February and early April. He expects roughly a
four year decline in solar activity to the next minima.
 
Lawrence, GJ3RAX of Jersey, one of the Channel Islands between
England and France, wrote on May 14: "Since the beginning of this
month I have been catching some good Es openings on 6 meters. On May
1 I was getting into EA3, EA5 and EA6. On May 7 it was HA, YO and
ER. This evening I got some more in EA as well as ZB2, EA8, EA9, CT1
and CN8. It is interesting that the openings are occurring about
once a week, although I might have missed a few. I usually check
DXmaps (see http://www.dxmaps.com) to see if anything is happening,
and there have been more over Europe but not reaching me.  Soon it
should be happening again almost every day.
 
A long time ago I was told that there can be a correlation between
thunderstorms and E-skip. The first two of those openings this month
did coincide with lightning activity that was about half way between
me and the DX worked. There was not any indicated for the opening
today.
 
I have not had many QSOs this year on 10 meters and the band is
usually much quieter than it should be now. Back on March 24 I did
get W1AW/5 when it was being operated from New Mexico. I have heard
it from other states but not as strong as that one was. The best DX
recently was a couple of days ago on May 12 when I got VP8LP (Port
Stanley, Falkland Islands).
 
The 10 meter QSOs were with 100 watts to an R5, as I do not want to
scare the neighbours with an HF beam. On the VHF bands I am still
using a log periodic that covers 50 MHz to 1300 MHz.  I am planning
on replacing it soon with higher gain antennas for those bands as my
results this year have not been good on 70 cm and 23 cm, although
last year I had some nice ones if I was on at the right time.
 
Looking at the solar graph we are now very obviously into the second
peak which, for a change, is being indicated as being much stronger
than the first one. What has surprised me is that the photos of the
sun are still showing a similar number of sunspot groups in the
north and the south.  From previous cycles I would have expected to
see most of them in the south by now. As we usually see the second
peak as being weaker than the first one I am wondering if we could
be due to see a third peak this time that could be weaker like the
first one. It is amusing to speculate on such things from following
the photos and graphs but I am not aware of any reason why this
should happen based on the previous cycles."
 
Max White, M0VNG of Worcester, England sent this article about solar
wind and lightning on Earth:
http://www.bbc.com/news/science-environment-27406358
 
Norman Kenyon, G4AYU of Lancashire sent a link concerning that huge
July 2012 CME that was fortunately a week too late to affect Earth.
Had it occurred on July 16, 2012, the effect on telecommunications,
satellites and the electric power grid would have been a major
disaster. Here is the link:
 
http://www.unmannedspaceflight.com/index.php?showtopic=7843&hl
 
Carl Zelich, AA4MI of Chuluota, Florida reports that on two
occasions earlier this month he worked a Russian Antarctic station,
RI1ANT on 40 and 20 meter CW. On May 3 at 0249 UTC the QSO was on
7.011 MHz, and their signal was 559. On May 5 at 0147 UTC they were
599 on 14.032 MHz. Carl used 40 watts and a dipole for both
contacts.
 
Carl also reported: "Also heard their operations on three additional
dates/times but without any QSOs. I think that many operators did
not recognize the significance of the 'RI' and just assumed it was
just another Russian station. Too bad because it was several days of
missed opportunities."
 
An item in last week's bulletin mentioned sprites, and on May 11
Martin McCormick, WB5AGZ wrote:  "Back in the days of analog
television, I used to sometimes listen to video carriers from
Channel 7 which is 175.25 MHz with offsets at 175.24 and 175.26 MHz.
 
Before the change to DTV, Stillwater, OK could faintly receive
signals from both Wichita, KS and Wichita Falls, TX on a normal day.
With active thunderstorms in the area, but not too close to here, I
remember hearing the carriers pop up in level a bit during a
lightning discharge. The effect is similar and about as long-lasting
as a meteor ping only without the Doppler Effect. If you have a
receiver with a BFO for those frequencies, the note of the carrier
gets louder for maybe 1-tenth to 1-quarter of a second at about the
time one heard the static crash.
 
If a storm was between two stations up to a few hundred miles apart,
one might get a meteor-style path for a fraction of a second.
 
The Channel 7 weak-signal listening ended many years ago when KOCO
Channel 5 in Oklahoma city put it's digital output on VHF Channel 7
plus all the other analog Channel 7's left the air.
 
Another strong steady carrier source was the Air Force Space Fence
transmitter at Lake Kickapoo near Wichita Falls, TX. The system was
shut off in October of 2013 due to budget constraints, but its
700-kilowatt ERP transmitter on 216.97 MHZ was designed to reflect
off of satellites as they passed over the United States. It also
bounced off aircraft as they flew overhead and I remember one
evening a few years ago, tuning that frequency to hear an almost
continuous barrage of sound that can best be described as sounding
like a crackly phonograph record or bowl of Rice Krispies. It so
happened there was a large thunderstorm over the Wichita Falls area
and I strongly suspect that each lightning discharge was creating an
ion cloud that dissipated almost as quickly as it occurred.
 
CW might have worked, but I can't imagine any other mode of
communication working properly.
 
A read of Wikipedia searching for Air Force Radar Fence will get you
a description of the system and why it no longer exists. It was
actually 3 VHF transmitters and 6 receiving sites with Lake Kickapoo
being the largest transmitter site. Strong steady carriers for
propagation experiments are an endangered species.
 
As for Es, there are still a large number of analog TV signals in
Mexico and other countries outside of the US and Canada. One
North-South Es opening occurred around 1400 UTC on Sunday May 4, and
was indicative of something I have heard numerous times. Mexican TV
signals with local quality sound, full-quieting audio appeared on TV
channels 2-4 with nary a beacon or QSO audible on 6 meters. I don't
know if it is because nobody is on or maybe the coverage area of the
path is extremely narrow but one would expect to hear something on
6. At other times, the low end of 6 sounds like 20 during a contest,
so it is hard to say what is happening.
 
Stillwater, Oklahoma is roughly 36 deg N, 97 deg W. Last Sunday's
opening lasted a couple of hours but was truly strong for only half
an hour or so."
 
N0JK, Dr. Jon Jones, MD of Lawrence, Kansas wrote about
trans-equatorial propagation on May 12, 2014: "Several Es to TEP
openings over the weekend.
 
May 10 many on the East Coast through W8 worked ZD7VC (St. Helena
Island) around 1900z. TJ3SN (Cameroon) also worked by W1.
 
Sunday May 11 Es to TEP across much of the Midwest states. Here in
Kansas I worked LW5EE from home with a M2 HO loop at 2155z. Portable
worked PY1RO and PP1CZ. PY1RO peaked to 599 at times."
 
Jon never indicated which mode he made these contacts on, but since
PY1RO had a signal report of 599 instead of 5x9, I will assume the
mode was CW. These reports concern 6 meters.
 
George Hall, N2CG of Saddle Brook, New Jersey wrote about the
Mother's Day six meter band opening from North America to South
America.
 
"I wanted to report my experience in the Mother's Day 2014 6 meter
band opening between North America and South America from my
Northern New Jersey, FN20wv, QTH.
 
My 6 meter station consists of a KLM 8 element log periodic Yagi
antenna at 35 feet above ground and my transceiver is an Icom IC-756
Pro III at 80 watts driving a pair of 8874 tubes in my Alpha 374
converted to a 6 meter mono-band amp yielding 800 Watts output
power.
 
Around 3:30 PM EDT/1930Z I received a text message on my phone from
Rob, KC2RDW alerting me that 6 meters was open. I soon got on the
air and at 1943Z I worked 9Y4VU (Trinidad and Tobago) in FK90 on CW
on 50.106 MHz. Following that QSO I started hearing W4 land stations
(GA, FL, AL) in QSO with other stateside stations. I kept on
monitoring the band for possible DX stations and beginning around
2100Z I started to hear South American stations coming in fairly
strong, and they got stronger as time progressed for the next 1-1/2
hours!
 
I worked PV8ADA, LW3EX, LU4FPZ, PY1RO and FM5WD all on CW and on SSB
I worked LU9AEA, LU9EOF and CX4CR. All signals were S7 or greater.
 
I've been operating on 6 meters for over 37 years and to date I've
never heard South America stations coming into Northern New Jersey
so strong and so long as I witnessed on Mother's Day 2014. This
opening yielded me CX and LU for two new 6m DXCC entities!"
 
We received another report from N0JK on May 14: "Received many
reports about the big Mother's Day, May 11, 6 meter Es to TEP
opening.  I worked LW5EE at 2155z using the attic M2 HO loop with
559 reports.  Portable with the 2 el Yagi I logged PY1RO and PP1CZ
at 2220z.
 
Heard PV8ADI (not sure if via multi-hop Es or Es - TEP) for over an
hour but no QSO.
 
The opening was due to Es propagation linking to the afternoon TEP
on to deep South America. N0LL EM09 worked FG8OJ and TG9AJR via
regular Es during this opening and there were many Es contacts
spotted confirming the mode.
 
The next afternoon May 12 I heard LU5FF at 2210z while driving from
KC to Lawrence on 50.106 MHz."
 
Jon sent another report/observation on May 14 concerning the May 6
report from TI3/W7RI which said "But beginning about a week ago,
with the dip in solar activity, there's been almost nothing but a
few weak sporadic E openings into the Leeward Islands."
 
Jon noted, "This is a seasonal effect, not directly related to solar
activity or solar flux. There is often strong afternoon TEP
propagation from the South Pacific to Central America on 6 meters in
March and April during solar cycle peaks. I recall similar
propagation from American Samoa in April, 2000 during solar cycle
23. It usually weakens and dissipates by the end of April."
 
A comment regarding reports from readers:  Please tell us your
callsign, location, which band and mode you were operating on, and
the date and time. Often we receive most of this information, but
have to hunt down the rest or make assumptions at the last minute
before publication.  Thanks!
 
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 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 May 8 through 14 were 124, 123, 125, 161, 164,
138, and 162, with a mean of 142.4. 10.7 cm flux was 148.1, 152.3,
152.1, 164.4, 162.9, 159.4, and 163.2, with a mean of 157.5.
Estimated planetary A indices were 20, 8, 9, 12, 8, 5, and 6, with a
mean of 9.7.  Estimated mid-latitude A indices were 13, 8, 10, 10,
10, 7, and 8, with a mean of 9.4.
NNNN
/EX