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ARRL Propagation Bulletin ARLP004 (2009)

SB PROP @ ARL $ARLP004
ARLP004 Propagation de K7RA

ZCZC AP04
QST de W1AW  
Propagation Forecast Bulletin 4  ARLP004
From Tad Cook, K7RA
Seattle, WA  January 23, 2009
To all radio amateurs 

SB PROP ARL ARLP004
ARLP004 Propagation de K7RA

Monday revealed another shy sunspot.  Sunspot 1011 appeared
suddenly, then it was gone.  Its configuration and location did not
identify it as a Cycle 23 or Cycle 24 spot.  On Monday, January 19
the sunspot number was 13.

Geomagnetic conditions continued to be very quiet, and yesterday,
Thursday, January 22 was another exceptionally quiet day, similar to
January 12, and December 28-30.  You can check the web site
http://www.swpc.noaa.gov/ftpdir/indices/DGD.txt to see all those
zeroes.

This bodes well for the CQ World Wide 160-Meter CW Contest this
weekend.  The Planetary A index is predicted to be at 5 until
January 27-31, when the predicted values are 10, 8, 5, 8 and 5.

Geophysical Institute Prague predicts quiet geomagnetic activity
January 23-25, quiet to unsettled January 26, unsettled January 27,
quiet to unsettled January 28, and back to quiet by January 29.

Note in our data at the end of the bulletin we do not have solar
flux resolved to a tenth of a point as we usually do.  Thursday
night and Friday morning we have not been able to access the data
from the observatory in Penticton, so these are the numbers provided
from NOAA.

Another hiccup in the data stream this week was on Thursday
afternoon, when a geo-alert message via email from Australia's IPS
Radio and Space Services (on the web at, http://www.ips.gov.au/)
turned out to be a vicious anti-Semitic screed broadcast during a
security breach.  I phoned the duty forecaster in Sydney, New South
Wales, who verified it was a security problem which their IT staff
was investigating.  You can subscribe to these alerts via their web
page at, http://www.ips.gov.au/mailman/listinfo/ips-geo-warning.

Among many interesting web pages they have is one devoted to sunspot
numbers, both past and predicted, at
http://www.ips.gov.au/Solar/1/6.

Still another reporting glitch this week was from NOAA with the
daily 45 day prediction of solar flux values and planetary A index.
These are issued daily, and are available at,
http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html.  On some days
they will issue more than one report if their forecast changes.  But
on Tuesday, January 20 the report at 2059z had four more reports
until 0039z, and all of them appeared to contain identical data.  We
contacted Viola Raben at the Space Weather Prediction Center, who
said the Air Force (which NOAA collaborates with on this forecast)
had a glitch which caused the posting of an additional forecast
every time they tested something in their system.

Steve Friis, WM5Z of Las Cruces, New Mexico reminded us of a nifty
Firefox web browser extension that fetches solar indices
automatically and displays them in the lower-right information bar.
It is called "Propfire," and Steve notes that you can install it in
Firefox by clicking on Tools at the top, then Add-ons.

In the search field enter Propfire, and N0HR Propfire will display.
Clicking "Add to Firefox" installs it.  Firefox is an open source
web browser similar to Microsoft's Internet Explorer, but it is
produced free by a community of programmers, similar to the way the
Linux operating system is built and maintained.  You can download
Firefox at, http://www.mozilla.com/en-US/firefox/.

When I set it up, I noticed that it has an option to display current
sunspot number in addition to the usual solar flux, A and K index.

Jeff Hartley, N8II of Shepherdstown, West Virginia reported
disappointing conditions last Saturday, January 17.  He wrote, "It
seemed like the worst day I can remember for low solar activity,
long skip zones, and early closure of 20M to EU. I took part in the
HA DX contest and by about 1610Z, only a very few Europeans were
left on 20M. Before that, signals were much weaker than normal, but
some Moscow area stations were heard around 1300Z as well as
Scandinavia, so there was no big disturbance. Then, the NAQP SSB
started (North American QSO Party, sponsored by National Contest
Journal) at 1800Z and skip zones were very long, only CA/OR were
worked on 15M and 20M was the worst ever probably in NAQP with TX
about the closest state that could be worked most of the day."

Jeff continues, "I worked two very loud unfluttery KL7s on 20 and
loud VE7s, so the K had to be low. 40 was skipping over most of New
England by about 2030Z (1-1/2 hours before sunset) and the closest
signals to the south were in SC. Conditions did rebound a bit on
Sunday and there was some sporadic E to the NW at times. I was able
to work W0GXQ/M (a very hearty soul, not a necessary trip, just
putting out counties for the county hunters) on 40 thru 10M from one
county line in central ND around 16Z, and we made 15M a couple of
times. I heard MI loud around 21Z on 20M. There may have been an Es
opening on 6M in the VHF SS, but I didn't take part."

Early this morning, January 23, Jeff followed up with, "Things seem
much better this week with 2 nights of openings to EU on 30M at
sunset as opposed to nothing after 1700-1800Z from EU in quite a few
days. 160 was in great shape early Friday today with UA9MA, OY9JD
(loud), 4Z5KJ, several UA3/4s working as far as AZ, and HA3MU S9 +
15 db in the 0100Z hour, SM4CAN was also S9+. And I worked 4S7NE on
80 CW at the same time."

An interesting email about possible meteor scatter communications on
60 meters arrived from Larry Jones, K5ZRK who operates next to
Tallahalla Swamp in Sandersville, which is in southern Mississippi,
about 31.78 degrees north latitude.

Larry wrote, "I operate only 60 meters and only operate QRP! I do a
LOT of operating and run a lot of skeds, therefore propagation is
VERY important. I use a quarter-wave vertical antenna insulated from
ground, with 120 quarter wavelength radials, and all those are tied
into a 1.6 acre chain link fence surrounding my property. I also use
a 60 meter inverted-V on transmit when I am working close in
stations. I use a LOW 60 meter inverted-V on receive so that I can
reduce the noise and the preamp on my Icom 703."

Larry continues, "Frequently during skeds at night I hear what seems
to be meteor burst. I also hear these early in the morning when
working the gray line. This is not always the case so that makes me
wonder if there are meteor bursts on 60 meters."

He goes on to say, "I was an avid meteor scatter operator back in
the early 90s with my old call WB5KYK and I ran on 6, 2 and 432 but
I sit there for hours listening to this when running skeds on 60
meters. I can remember on 6 meters I would get upset when there was
E-skip during a meteor shower because the E-skip would ruin the
shower, I would be working E-skip instead of meteor scatter.  The
propagation on this band is fascinating to me, the gray line is
phenomenal on this band and running QRP (10 watts on SSB) I have
worked into Hawaii, and California is not hard.  Skeds are so
interesting on this band but this phenomenon I am observing has me
puzzled because it sounds like meteor scatter. If it isn't, then
what is it?  This can be a useful tool if I can just figure out what
it is AND to further give you something to think about.  I observe
this even more so during meteor showers and during the early morning
hours (1100-1239z which is when meteors are prevalent)."

Interesting information, and it makes sense that ionized trails from
meteors could provide a sporadic-E like propagation path, even on 60
meters.  Carl Luetzelschwab, K9LA commented that meteor scatter has
been detected at 2 MHz, and pointed out a PhD thesis titled "Medium
Frequency Radar Studies of Meteors," by Stephen I. Grant, July 2003
at the University Of Adelaide Department Of Physics that describes
this.

In a subsequent email, K5ZRK wrote, "Next month there will be two
showers that are classed as medium showers. I HOPE to set up some
skeds for both. I think one of the things that is interesting about
meteor scatter on 60 meters is the antenna issue.  What would be the
best antenna for meteor scatter on this band? I feel this is
something we will learn by experience and this band is not old
enough yet for us to know what is going to work best, especially
when it comes to propagation. It seems it would be somewhere between
the propagation on 80 and 40 meters, but I have found this band to
be a totally different creature!"

Finally, Spaceweather.com has a fun tool for displaying a graph of
11 years of smoothed sunspot numbers, centered on any date you
choose, going back over 250 years. What was sunspot activity like
when you were born?  Check it out at,
http://www.spaceweather.com/glossary/sunspotplotter.htm.

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

For more information concerning radio propagation, see the ARRL
Technical Information Service web page at,
http://www.arrl.org/tis/info/propagation.html.  For a detailed
explanation of the numbers used in this bulletin see,
http://www.arrl.org/tis/info/k9la-prop.html.  An archive of past
propagation bulletins is at, http://www.arrl.org/w1aw/prop/.

Monthly propagation charts between four USA regions and twelve
overseas locations are at http://www.arrl.org/qst/propcharts/.

Instructions for starting or ending email distribution of this
bulletin are at http://www.arrl.org/w1aw.html#email.

Sunspot numbers for January 15 through 21 were 0, 0, 0, 0, 13, 0,
and 0 with a mean of 1.9.  10.7 cm flux was 71, 71, 72, 71, 71, 70,
and 69 with a mean of 70.7.  Estimated planetary A indices were 4,
2, 2, 2, 9, 3 and 2 with a mean of 3.4.  Estimated mid-latitude A
indices were 4, 2, 2, 2, 7, 1 and 2 with a mean of 2.9.
NNNN
/EX


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