ARRL

ARRL Propagation Bulletin ARLP028 (2003)

SB PROP @ ARL $ARLP028
ARLP028 Propagation de K7RA

ZCZC AP28
QST de W1AW  
Propagation Forecast Bulletin 28  ARLP028
From Tad Cook, K7RA
Seattle, WA  July 11, 2003
To all radio amateurs 

SB PROP ARL ARLP028
ARLP028 Propagation de K7RA

This has been quite an interesting week for propagation and a
fruitful one for DXers, on both HF and VHF. Last week's Propagation
Bulletin ARLP027 mentioned that on July 9-10 we could experience
some relatively stable and quiet geomagnetic conditions. This could
be a welcome relief from the months of high A and K indices, solar
flares, solar wind and geomagnetic storms.

The actual conditions for July 8-10 were wonderful, with conditions
much quieter than predicted. The planetary K indices for July 8-9
were all ones and twos, and the planetary A index for July 8-10 was
5, 6 and 8. The middle latitude indices were even better, with a
Fredericksburg K index of 0 for five of the three-hour periods on
July 8-9. The middle latitude A index for July 6-10 as reported at
http://www.sec.noaa.gov/ftpdir/indices/DGD.txt was 10, 9, 3, 3 and
6. Geomagnetic indices haven't been so quiet since February 24-25 of
this year, when this bulletin reported A indices of 6 and 5, and an
average A index for the week of 11.1, nearly three points lower than
this week's average of 13.7.

On Wednesday evening local time in Seattle I was hearing many strong
signals on 17 and 20 meters, and worked European stations on 17
meter CW from my car parked in front of my house. But the big
surprise this week was 6-meters, where John Kiesel, KE7V worked
Europe from land owned by K7HV on Washington State's Olympic
Peninsula. John used a five element Yagi. There were many other
great 6-meter reports this week, which was surprising, because of
late the notable 6-meter openings seemed to occur during periods of
high geomagnetic activity.

Bob Sluder, N0IS wrote on Monday July 7 with a reference to the 50
MHz Propagation Logger at http://www.dxworld.com/50prop.html. He
noted the European stations working North America, and wondered
about the K index and the fact that it was nighttime in Europe when
this was going on. On that day sunspot 375 was still growing, but
starting to rotate toward the edge of the visible solar disk, where
it disappeared after July 9. The geomagnetic indices were also
really starting to quiet down on Monday.

Gene Zimmerman, W3ZZ sent some comments about West Coast stations
working Europe on 6-meters, and said VE7SL had 44 European contacts
on Tuesday from 1715-1908z. He also noted double hop E layer skip on
6 and 2-meters from the East to West coast, and passed along a
report from Dave Bernhardt, N7DB from grid CN85 in Boring, Oregon,
which is partially reproduced here in the following seven
paragraphs:

"NN7J reports the following: G0JHC 1632z; I4EAT 1653z; ON4OAI 1701z;
I0JX 1716z; and DL7QY 1736z. PA7MM & PA0HIP were also worked. Dan
was heard by MW1MFL at 1619z and by PA5DD at 1815z. Weak EU signals
were heard by Dan during much of the 1800z hour before finally
disappearing."

"K7RWT reports the following: I0JX 519/559 1719z; PA0HIP 419/519
1725z; PA0VST 539/559 about 1730z and partial with PA7MH(?) at
1756z. Dave reports hearing DL6AMI, IK2GS? plus a number of ON
stations."

"WX7R gives the following report: I0JX 1719z; ON4AOI 1732z; ON4IQ
1738z; PA5TA 1739z; IK4DCT 1748z; IK2GJO(?) 1750z; PA0HIP 1753z; and
PA9KT 1755z. Other stations heard by John include PA2VSA, IZ2AAJ and
other weak PA's and I's. One station that both John and I tried to
work was IW5BML/P on 50.139. Could not get that station's attention
that he was getting out to the West Coast! John mentioned that W1QT
(CN84) south of Salem also worked 3 EU countries with a '706 and
3el!"

"I will certainly be interested in VE7SL's report as Steve had EU
'til around 2000z with quite a few new countries worked. Looks like
Steve got a few countries in the Balkans to boot."

"This station worked I0JX 559 at 1717z and PA0HIP 559 at 1750z.
Station here is a 'tired' TR-6 with around 50W output to a CC 5el up
25'. Very modest 6M station at the moment, but really amazed at
working Rome with such gear. Working I0JX and other European
stations gave operators on this end the "shakes" from the extra
excitement. Also heard here was PA5TA. W7KNT and K7TNT were heard on
backscatter working into EU during the morning."

"Remember, this is only the SECOND E type opening that almost all
operators have experience in our LIFETIMES' out here."

"Looks like this was a fairly widespread opening from the reports
known at this time. EU stations worked down to at least CN80 and up
to CN88/9 (VE7SL.) Looks like the signals were coming in at a high
angle as this station did well with a low antenna compared to other
stations in this area with higher antennas."

Regarding high geomagnetic activity after the peak of a solar cycle,
Carl Luetzelschwab, K9LA wrote to say that the geomagnetically most
active part of a solar cycle is in its initial decline, and we're
probably in the worst (best for VHF) time right now. The quietest
time is a couple years past the solar minimum. He also notes a
seasonal effect, with summer and winter generally quieter than the
equinoxes.

After all this, it seems there is little time to report on recent
60-meter activity. Martin McCormick, WB5AGZ of Stillwater, Oklahoma
reported good 60-meter reception, especially after local midnight.
He says it is like 40-meters without the broadcast QRM.

Glenn Thomas, WB6W reported S7-S8 noise levels during the opening
hours of 60-meters while mobile in Fremont, California. Before
midnight he heard signals to the east, but none were strong. After
midnight it was bedlam, but he worked a number of other California
stations. He reported strong signals from WB6NOA in San Diego. Most
notable was his contact with Bonnie Crystal, KQ6XA, who Glenn said
was bicycle mobile in Oregon. Bonnie had a post this week on
http://www.qrz.com reporting that 5403.5 kHz is common to both the
US and UK. She also wrote that HFpack, a group devoted to portable
HF operation has been using 5371.5 kHz as a calling frequency for
backpack portable and pedestrian mobile operators.

This weekend is the IARU HF World Championship. The predicted
planetary A index for Friday through Monday, July 11-14 is 25, 20,
15 and 15. Solar flux is expected to slowly drift down to a minimum
of 115, where it is expected to stay from around July 17-22.

Sunspot numbers for July 3 through 9 were 147, 130, 88, 114, 140,
149, and 125, with a mean of 127.6. 10.7 cm flux was 132.2, 140,
141.9, 129.6, 133.3, 131.3, and 126, with a mean of 133.5. Estimated
planetary A indices were 17, 25, 17, 12, 14, 5, and 6, with a mean
of 13.7.
NNNN
/EX