[South Florida DX Association] ARLP004 Propagation de K7RA

[Bill Marx]

> Propagation Forecast Bulletin 4  ARLP004
> From Tad Cook, K7RA
> Seattle, WA  January 27, 2006
> To all radio amateurs 
> 
> SB PROP ARL ARLP004
> ARLP004 Propagation de K7RA
> 
> To recap the week's solar activity, the average daily sunspot number
> rose nearly 25 points to 49.4, about double last week's count of
> 24.6. Average daily solar flux rose nearly 11 points to 91.4.
> 
> This week double-sunspot 848 continued to expand as it transited the
> Earth-facing side of our nearest star. But by today, Friday, January
> 27, it is moving out of the sun's visible area. In the middle of
> this week the interplanetary magnetic field moved south, and a
> moderate solar wind drove the planetary A index to 29 on January 26.
> 
> By this time next year solar activity will probably be even lower
> than now, with many days in succession with no visible sunspots. To
> see what this is like, go back almost ten years to look at our
> propagation bulletins in September 1996. You can find archives of
> the old bulletins at http://www.arrl.org/w1aw/prop/ and click on
> propagation bulletins for 1996. Look at bulletins between 39 and 43
> and you will see weeks of reports such as, sunspot numbers at "0, 0,
> 0, 0, 0, 0 and 0, with a mean of 0." These periods of low activity
> aren't good for the higher HF bands, but can be great for 160 and 80
> meters.
> 
> An email came in this week from Bill Gallier, W4WX, who writes that
> he and K4QD are going to Ascension (ZD8) February 21-28. He wanted a
> propagation prediction for 160 meters for those days to various
> continents. But all of the popular propagation prediction software
> is written around an algorithm that only works down to 3 MHz, and
> not that well on the lower frequencies above 3 MHz. About the best
> we could do was to recommend trying paths to various locations when
> darkness is over both ends of the path. You can use a propagation
> program like W6ELprop for this, because part of the prediction is a
> listing showing the times for sunrise and sunset at both locations.
> As always, you can find W6ELprop free at,
> http://www.qsl.net/w6elprop/.
> 
> John Winans, WA2LGE wrote in asking about lists of beacons. I
> googled a query and found one that is new to me at,
> http://www.ac6v.com/beacons.htm. Nice set of links to beacon
> software and lists of beacons, from VLF to VHF.
> 
> For this week look for a planetary A index of around 12 for today,
> January 27, and then 5 (very quiet) on every day through February 2.
> Geophysical Institute Prague predicts unsettled activity for January
> 27, quiet to unsettled for January 28 and February 1 and 2, and
> quiet conditions for January 29 to 31. Sunspot activity will remain
> low, and the 10.7 cm solar flux is predicted around 85 for January
> 27-28 and 80 from January 29 through February 2.
> 
> If you would like to make a comment or have a tip for our readers,
> email the author at, k7ra at arrl.net.
> 
> For more information concerning radio propagation and an explanation
> of the numbers used in this bulletin see the ARRL Technical
> Information Service propagation page at,
> http://www.arrl.org/tis/info/propagation.html. An archive of past
> propagation bulletins is found at, http://www.arrl.org/w1aw/prop/.
> 
> Sunspot numbers for January 19 through 25 were 48, 33, 28, 60, 73,
> 62 and 42 with a mean of 49.4. 10.7 cm flux was 88.6, 90.7, 93.8,
> 92.8, 92.4, 92.6, and 89, with a mean of 91.4. Estimated planetary A
> indices were 7, 6, 4, 6, 15, 7 and 7 with a mean of 7.4. Estimated
> mid-latitude A indices were 5, 4, 4, 4, 13, 6 and 8, with a mean of
> 6.3.
> NNNN
> /EX
> 
> 
>