[South Florida DX Association] ARLP022 Propagation de K7RA

[Bill]

ZCZC AP22
QST de W1AW
Propagation Forecast Bulletin 22  ARLP022
 From Tad Cook, K7RA
Seattle, WA  June 4, 2010
To all radio amateurs

SB PROP ARL ARLP022
ARLP022 Propagation de K7RA

Average daily sunspot numbers were up nine points to 25.3 for this week, 
compared to the May 20-26 period.  Average daily planetary A index rose 
nearly ten points to 14.3, and this rise in geomagnetic instability came 
with the increase in solar activity.

Sunspot group 1072, reported in last week's bulletin, was visible for 
nine days, until May 28.  When it was gone on May 29, three new groups 
appeared, 1073, 1074 and 1075.  On May 29-31 the daily sunspot numbers 
were 43, 40 and 39, but geomagnetic indices were high as well, with the 
planetary A index at 33 on May 29, and planetary K index up to five.  On 
the same day the college A index (Alaska) was 53, with college K index 
as high as seven.

On May 31 group 1074 was gone, and it was the last day groups 1073 and 
1075 were still visible.  On that day new group 1076 appeared, and 
through June 3 the total area (in millionths of a solar
hemisphere) was 20, 20, 40 and 190.  The increase from June 2 to June 3 
was big (up 375%), but curiously the sunspot number for those dates 
declined slightly, from 18 to 17.  Solar flux rose from 74 to 74.6.

The prediction from USAF and NOAA has solar flux slowly declining in the 
short term, from 75 for June 4 to 74 on June 5-6, 73 June 7-9, 72 on 
June 10, and 70 on June 11-17, then rising to a peak of 82 on June 28.  
Predicted planetary A index for the next seven days, June 4-10, is 10, 
8, 5, 8, 8, 5 and 5.

Geophysical Institute Prague predicts quiet conditions June 4, quiet to 
active June 5-6, quiet to unsettled June 7-8, and quiet again on June 9-10.

Some may have noticed at http://www.swpc.noaa.gov/ftpdir/indices/DSD.txt 
that NOAA showed a solar flux value of zero for June 2, which is 
impossible.  Don't know how that was left out, but you can always get 
the data from the source at http://tinyurl.com/ks8tvn which shows a 
solar flux value of 74.6 for that day.

ARRL Field Day is June 26-27, and this coincides with what may be the 
next short term peak in solar activity, according to the NOAA and USAF 
prediction, which calls for solar flux values for June
25-28 at 80, 80, 80 and 82.

Field Day 2009 was spotless, in fact there were no sunspots at all 
between June 25 and July 2, 2009.  Suppose that there are sustained 
daily sunspot numbers around 25 for the days leading up to Field Day  
2010?  What differences could we expect?

Checking W6ELprop from Southern California to Ohio, for example, shows 
very little difference, except on 15 meters there is a much greater 
chance for an opening.  Both show 40 meters opening up after 0000z, 
reaching optimum signal strength 0330-1030z.  Both show 20  meters open 
through the day, but weakest periods around 1330-1430z and 2300-0000z, 
and strongest signals through the night, 0100-1200z.

We see similar results from Atlanta to the center of the continental 
United States, somewhere in Kansas.  The path is quite a bit  shorter, 
and we see 20 meters opening a half hour earlier than last
year, at 1500z and lasting until 2130z, a half hour later than last year.

A similar test from Hawaii to the mainland shows a big improvement over 
last year, especially on higher frequencies, such as 15 meters. In Field 
Day there is no bonus for DX, and it isn't like ARRL
Sweepstakes in which multipliers are earned for each new section worked, 
so the only incentive is to work as many stations as possible.  But for 
a Field Day station in Hawaii, the increased
solar activity will make a big difference in the number of stations they 
can work.

Now at the beginning of a new month, we can look at our quarterly moving 
averages for sunspot numbers.  We use a sliding three month window for 
averaging the data, so the latest number is for March 1 through May 31, 
and centers on April.  For May 2009 through April 2010 the 3-month 
averages are 4.2, 5.2, 4, 4, 4.6, 7.1, 10.2, 15.2, 22.4, 25.7, 22.3 and 
18.5.  You can see that the numbers have declined a bit.

The monthly averages of daily sunspot numbers for 2010 are 21.3, 31, 
25.2, 11.2 and 20.

Floyd Chowning, K5LA and K5PHF, both in DM61 in El Paso, Texas and K7ICW 
in Las Cruces, New Mexico (DM62) all worked K7MAC in Nampa, Idaho (DN13) 
on June 2 at 1758z on 2 meter SSB.  This rare sporadic-e opening lasted 
30 minutes.  The distance from K5LA to K7MAC is 973 miles, according to 
my calculations.

If you check the K5LA entry at http://www.qrz.com/db/k5la you will see 
some detail on his propagation beacons on 30, 17, 10 and 6 meters, and 
his participation in propnet.org <http://propnet.org>.

David Greer, N4KZ of Frankfort, Kentucky wrote a detailed description of 
his 2 meter sporadic-E adventure.

"It's June so it must be time for the VHF bands to start rockin'. They 
did not disappoint on June 3 with 6 meters providing three-dozen SSB and 
CW QSOs from central Kentucky (EM78) to the West
Coast. Of course, the day before wasn't shabby either with a dozen 
contacts into W1 and the Caribbean.

"But it was June 3 that provided some memorable QSOs. In the midst of 
handling a pile-up of West Coast callers, I got a call from KD5CCG in 
Arkansas. That got my attention because it showed the E-skip distance 
was shortening up -- often a tip-off that E-skip will show up on 2 meters.

"So I set my TS-2000 and amp on 144.200 MHz and called several CQs while 
beaming west. Nothing, zilch. So I turned on the squelch and went back 
to my Icom Pro 3 on 6 meters.

"At 0047 UTC, N0YK came on the 2-meter frequency with an S9 plus SSB 
signal calling CQ. I answered him and we both logged 59 reports. He's in 
Kansas, DM98. That's western Kansas, almost to the Colorado line. 
Exactly 10 minutes later, WB2FKO, DM65, in New Mexico came roaring in 
with a strong "CQ 2-meter E-skip. Beaming east.

"Bingo, he was in my log too but not before I nervously asked him to 
repeat his call twice. Even after 41 years of ham radio, such a contact 
gives me chills. My logging program shows 1,173 miles
between our QTHs. I've been on and off 2-meter SSB since 1975 and it was 
only the second time I had worked New Mexico from Kentucky. Wow, nearly 
1,200 miles on 2 meters!

"At 0106 UTC, I worked N0QKY, also in Kansas and then made a quick QSO a 
minute later with KA0RID, another Kansas station. It's about 600 miles 
from my location to central Kansas and those are great 2-meter contacts 
but the nearly 1,200 mile QSO with New Mexico was really special. During 
the opening, I copied but did not work K7ICW, New Mexico, and N0POH, 
Colorado. At that point, things were quite busy on 144.200 MHz with 
QSOs, CQs and QRZs galore. I do wish guys would spread out a bit more 
during these openings!

"More than 30 minutes after I first heard and worked N0YK, I was still 
copying him but the signals were in the noise as the 2-meter E-skip 
opening was fading.

"I have modest stations on both bands. I run 200 watts out and a 
9-element M2 Yagi at 60 feet on 2 meters and 100 watts out to a 
4-element Yagi at 55 feet on 6. Antennas are important but time and time 
again it's proven that much of the battle at VHF is about being in the 
right place at the right time."

Thanks, Dave!

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

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

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 27 through June 2 were 11, 12, 43, 40, 39, 14, 
and 18 with a mean of 25.3. 10.7 cm flux was 72.7, 73.2, 73.7, 73, 72, 
72.7 and 74 with a mean of 73. Estimated planetary A indices were 4, 10, 
33, 19, 16, 12 and 6 with a mean of 14.3. Estimated mid-latitude A 
indices were 1, 7, 15, 14, 14, 9 and 4 with a mean of 9.1.
NNNN
/EX