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QST de W1AW  
> Propagation Forecast Bulletin 25  ARLP025
> From Tad Cook, K7VVV
> Seattle, WA  June 21, 2002
> To all radio amateurs 
> ARLP025 Propagation de K7VVV
> Field Day! This weekend is ARRL Field Day, possibly ham radio's most
> popular organized operating activity. In the past this bulletin only
> commented on domestic propagation for Field Day weekend, but this
> year for the first time Field Day is expanded to cover all of the
> Americas. The new rules say that anyone in IARU Region II may
> participate, and this covers all of North, Central and South
> America, Greenland, the Caribbean, as well as some Pacific Islands.
> IARU Region II is the same as ITU Region II, and you can see a map
> of Region II at, www.echelon.ca/iarumsr2/ituregions.html .
> Remember that in Field Day there is no multiplier or extra credit
> for number of states, sections, zones or countries worked. Contacts
> with stations in all areas count the same. This distinguishes Field
> Day from contests where top scorers pay close attention to working
> the maximum number of multipliers. In Field Day multipliers and
> extra credit are earned for operating low power, from batteries, and
> for generating publicity for amateur radio's emergency preparedness
> capabilities. See
> www.arrl.org/contests/rules/2002/rules-fd-2002.html for
> complete rules.
> Solar flux and sunspot numbers declined again this week. The daily
> average for sunspot numbers dropped by over 38 points and average
> daily solar flux was down by 14 points compared to the previous
> week, June 6-12. Solar flux reached a short term minimum last Friday
> at 131.4, and is now on the rise. Current projections show it
> peaking around 170 by the end of this month. The predicted flux
> values for Field Day weekend, Friday through Sunday are 150, 155 and
> 155.
> What we hope for this weekend and the days leading up to it are high
> solar flux and low geomagnetic activity. Currently the earth sits in
> a solar wind stream coming from a coronal hole on the sun. This
> could possibly trigger high-latitude aurora, but the current
> prediction for Saturday and Sunday is stable geomagnetic conditions.
> One way to get a feel for conditions this weekend is to look at the
> average Wednesday through Sunday solar flux (in this case solar flux
> values for Friday though Sunday are the predicted numbers) and
> Friday though Sunday average planetary A index for this year
> compared to past Field Days. The 5 day solar flux average for 1998
> through 2002 Field Days Are 111.6, 192, 177.3, 200.7 and 151.1. The
> three-day planetary A index average for the same years is 19.3,
> 14.3, 16, 8.3 and 8.7. So in terms of the numbers, 2001 looks the
> best, since it had both the highest solar flux and lowest
> geomagnetic index.  If you compare some paths using a propagation
> program such as W6ELprop (a new minor update version 2.61 is
> available for free from www.qsl.net/w6elprop/ ) for the
> numbers from 2001 compared to 1998, look at a domestic 15 meter path
> from California to Ohio. You'll see a radical difference. But you'll
> notice a slightly better path for 1998 on 40 meters.
> In addition to being Field Day weekend, this is also the first
> weekend of summer. This is not a great time for 10 meters, but check
> 10 meters for possible E-layer propagation rather than the better
> F-layer propagation we see on this band in spring and fall. For
> close-in propagation less than 1000 miles, your best band around the
> clock will be 40 meters, and 80 meters after sunset.
> W6ELprop was mentioned above, and also worth noting is the program
> from KU5S, WinCAP Wizard 3. A 30 day trial version is available for
> download at www.taborsoft.com/wwizard3 . Also at the
> Taborsoft site is an excellent help file with propagation basics
> written by NM7M.  Download it at the ''NM7M Tutorial - HF
> Propagation'' link toward the middle of the web page. Also check out
> ''The Sun, the Earth, The Ionosphere'' on the ARRL web site at,
> www.arrl.org/tis/info/k9la-prop.html . Another place to look
> for propagation info is the ARRL Technical Information Service web
> page devoted to the subject at,
> www.arrl.org/tis/info/propagation.html .
> Sunspot numbers for June 13 through 19 were 126, 102, 137, 132, 116,
> 174 and 127, with a mean of 130.6. 10.7 cm flux was 133.4, 131.4,
> 135.3, 136.7, 142.9, 142.9, and 145.8, with a mean of 138.3.
> Estimated planetary A indices were 11, 7, 7, 11, 7, 11, and 16, with
> a mean of 10.

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