ARRL Propagation Bulletin ARLP026 (2006)

ARLP026 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 26  ARLP026
From Tad Cook, K7RA
Seattle, WA  June 30, 2006
To all radio amateurs 

ARLP026 Propagation de K7RA

It was a fun Field Day weekend all over last week, judging from the
Soapbox comments and photos on the ARRL web site at  There are many great stories
on the site, but I enjoyed reading the N4SL report on the W7MRG
operation over 500 miles down the road to Montana from home in
Washington State.  Go to page 10 (click on 10 at the bottom of the
page on the above link) to find it.  Even with zero sunspots, the
homebrew wire antenna arrays and Montana hilltop sounded fabulous.
If you check the N4SL listing on, you'll see his wire
antennas at home sound quite similar to his Field Day setup.

Apparently there was some 6, 10 and 15 meter fun, although your
author didn't hear it here.  We put in a short casual mobile
operation on 20 and 40 meters, both CW and SSB, and were impressed
with how well the 7 foot monoband whip on the car worked on 40
meters.  Changing bands meant unscrewing an antenna from the trunk
mount and substituting another.

No sunspots last weekend, but a big new spot (897) rotated into view
this week.  Followed by spot 898, it looks like a moderately rising
solar flux and sunspot number will be with us through July 6.  A
solar wind stream caused elevated geomagnetic numbers on June 28 and
29, and this may happen again around July 3-5.  Geophysical
Institute Prague predicts quiet conditions over June 30 to July 3,
quiet to unsettled on July 4, unsettled to active on July 5, and
unsettled on July 6.

Last week's bulletin mentioned Carl Luetzelschwab, K9LA and his
article ''When Will the Bands Improve?'' in the current July 2006 QST.
Carl would like to correct his definition of the length of a sunspot
cycle.  The sentence in question should read ''The average length of
a sunspot cycle, from solar minimum with a minimum number of
sunspots (low electron density) to solar maximum with a maximum
number of sunspots (high electron density) and then back down to the
next solar minimum, is approximately eleven years.''

Roger Lapthorn, G3XBM wrote: ''I echo the comments last week about 6m
being a bundle of fun. I only have 5-10W QRP to a small vertical on
the side of the house but this has allowed me to work all across
Europe as far as Ukraine on SSB with 59 reports being the norm. Last
summer I managed a few north Africans but not yet this summer''.

''Not within my reach has been the amazing DX worked from Europe by
the 'big guns' running high power to large beams: Central America,
North America and, most amazing of all, a number of openings to JA
and even one to KL7. JAs seem to have been worked on several
mornings of late around our late breakfast time. This is over the
pole and a very long way for simply sporadic-E. I wonder what mode
this really is?''

Roger has a very nice web page at  Don't miss the
interesting links he has under Homebrew rigs for the remarkable
little QRP radios he constructed.

If you would like to make a comment or have a tip for our readers,
email the author at,

For more information concerning radio propagation, see the ARRL
Technical Information Service at For a detailed
explanation of the numbers used in this bulletin, see An archive of past
propagation bulletins is at .

Sunspot numbers for June 22 through 28 were 0, 0, 0, 13, 14, 33 and
38 with a mean of 14. 10.7 cm flux was 72.1, 71.8, 73.6, 74, 76.4,
78.5, and 83.5, with a mean of 75.7. Estimated planetary A indices
were 6, 2, 4, 5, 3, 6 and 18 with a mean of 6.3. Estimated
mid-latitude A indices were 6, 1, 2, 3, 1, 7 and 12, with a mean of