[SFDXA] ARLP021 Propagation de K7RA

[Bill]

> 
> SB PROP @ ARL $ARLP021
> ARLP021 Propagation de K7RA
> 
> ZCZC AP21
> QST de W1AW  
> Propagation Forecast Bulletin 21  ARLP021
> From Tad Cook, K7RA
> Seattle, WA  May 23, 2014
> To all radio amateurs 
> 
> SB PROP ARL ARLP021
> ARLP021 Propagation de K7RA
> 
> Over the past week we saw a decline in solar activity, and the
> 45-day outlook showed progressively weaker numbers as well.
> 
> Average daily sunspot numbers for May 15 to 21 were 129.4, while the
> previous average was 142.4, a 13 point decline. Average daily solar
> flux drifted from 157.5 to 128.5. The daily sunspot number on
> Wednesday dropped down to 100 and on Thursday it was only 70, a
> level unseen seen since January 28.
> 
> Last week the solar flux prediction for Friday through Sunday on
> Field Day (June 28 and 29) was 125 on Friday and 135 on Saturday and
> Sunday. But the daily forecast on May 19 changed, with predicted
> solar flux at 120 on all three days, where it still remains. Prior
> to May 19 solar flux was predicted to peak at 165 on June 10 and 11,
> but that has now been revised downward to 135 and 130.
> 
> The latest prediction has solar flux at 105 on May 23 to 26, 100 on
> May 27 to 29, 110 on May 30, 120 on May 31 through June 3, 125 on
> June 4 and 5, 130 on June 6 and 7, 135 on June 8 to 10, 130 on June
> 11 and 12 and 125 on June 13 to 15. Flux values then drop down to
> 105 on June 22 to 24.
> 
> Predicted planetary A index is 8 on May 23, 5 on May 24 and 25, 8 on
> May 26, 5 on May 27 through June 3, 12 on June 4, 8 on June 5 to 8,
> and 5 on June 9 to 16.
> 
> F.K. Janda, OK1HH sends us his weekly geomagnetic outlook. He
> expects quiet to unsettled activity May 23, mostly quiet May 24,
> quiet May 25, quiet to active May 26, quiet to unsettled May 27,
> quiet May 28 and 29, quiet to active May 30 and 31, mostly quiet
> June 1, quiet June 2, quiet to active June 3, active to disturbed
> June 4, quiet to active June 5, active to disturbed June 6, quiet to
> unsettled June 7, quiet June 8 and 9, mostly quiet June 10, quiet to
> unsettled June 11, quiet June 12, mostly quiet June 13, quiet June
> 14 to 16, and quiet to active June 17 and 18.
> 
> Lawrence, GJ3RAX of Jersey (not New Jersey, but the old Jersey, the
> Isle of Jersey in the United Kingdom) says "Not much to report from
> here this time. There have been several more Es openings on 6 meters
> during the last week but mostly to places within Europe that are
> already on my list for this year although I have added a few new
> grid squares to my annual table in the VHF group. Most QSOs have
> been with Italy and Spain."
> 
> "Now hoping to be on at the right time to catch openings again on 4
> meters and eventually on 2 meters."
> 
> Lawrence (who doesn't seem to use a last name) mentioned the 4-meter
> band, which many may be unfamiliar with. Four meters is used in only
> a few countries, and the common allocation is 70-70.5 MHz.
> Apparently Great Britain at one time also had a 5 meter amateur band
> at 56 MHz.  Perhaps 70 MHz will be allocated for radio amateurs in
> the United States some day. For more information see
> http://en.wikipedia.org/wiki/4-meter_band , http://www.70mhz.org/
> and http://g1efu.webs.com/4meters.htm .
> 
> Pete, K2ARM of Fort Edward, New York (about 50 miles north of
> Albany) reported on May 20, "We have had a few openings on 6 meters
> in May but not for long. Even though the big guns have been working
> into Europe and South America, I haven't heard much on my dipole.
> But on May 11 I worked PV8ADI, LU4FPZ, LW3EX, and CX7CO on 6 meter
> CW plus a few states. I only run 40 watts to a dipole and only use
> CW."
> 
> "On May 18 the band opened up around 1300 UTC and stayed open until
> 0000 UTC. Signals were 30 to 50 over S9 from the Midwest at times
> and around 2210 UTC I worked WN6K and AI6O in California. Soon
> after, XE2CQ came pounding in but I could not get through. It looks
> like even though 6 meter sporadic E started out late, it may be
> better than last year."
> 
> On May 22 Pete wrote, "6 meters was open again last night until late
> in the evening. There were beacons from everywhere but not many
> stations on. My dipole is only up 20 feet and I am in a valley,
> great for DX!!!"
> 
> Thanks, Pete.
> 
> For anyone considering six meters, remember that a half-wave dipole
> is only about 9 feet plus 3 inches long for the low end of that
> band.
> 
> Scott Bidstrup, TI3/W7RI wrote on May 21:
> 
> "Those were interesting responses you posted last week to my inquiry
> about the possibility of VHF propagation as a result of lightning
> sprites. They seem to confirm what I conjectured. I think
> investigation of this could be a good subject for someone's Ph.D.
> thesis."
> 
> "The declining solar activity has taken its toll down here on 6
> meter propagation. There have been almost no openings the last
> couple of weeks, and what there have been, were short and rather
> sparse. I logged the YV4AB beacon about a week ago, as did YS1AG
> yesterday, the east-west path in both cases demonstrating that
> sporadic E does exist at these latitudes, though it is much rarer
> and sparser than in the United States or Europe."
> 
> "Meanwhile, the afternoon transequatorial openings from the States
> into South America have been continuing almost daily, and even
> though the paths go right over our heads here in Central America,
> we're still hearing nothing at all here on the ground. TI5XP has
> built a high gain beam for six, on a 42 foot boom, and even with it,
> he's been hearing nothing. I am starting to see some evening TEP in
> Europe on the maps in the last few days; since that is a different
> mode, perhaps it will yield us some propagation. We can only hope."
> 
> Scott sent along this interesting article, another one mentioning
> that huge July 2012 solar flare:
> 
> http://news.discovery.com/space/huge-solar-flare-reveals-explosive-magnetic-trigger-140521.htm
> 
> This weekend is the CQ World Wide WPX CW Contest. The SSB weekend
> was in March. See http://www.cqwpx.com/ for further information.
> 
> Summer solstice is only four weeks away, at 1051 UTC on Saturday,
> June 21.
> 
> To illustrate what summer propagation may be like compared to
> Spring, I ran some arbitrary numbers on W6ELprop for a path from
> Cleveland, Ohio to Germany with a sunspot number of 130, on the
> twenty-third of March (near the equinox), April, May (today) and
> June (near the solstice, all on the twenty-third of each month.
> 
> Examining 15 meters, in March we see the path begin to heat up
> around 1200 UTC, becoming quite promising at 1400 UTC with a
> relative signal level of 47, changing to 48 at 1700 UTC, 50 at 1900
> UTC, 51 at 2000 UTC, 52 at 2100 UTC and 53 at 2200 UTC. Then
> prospects begin to fade until the path is unlikely to support
> propagation by 0100 UTC.
> 
> For the same path on April 23 we see 15 meters begin to open at 1230
> UTC, with a relative signal level rating of 45 but with chances of
> an opening increasing at 1830 UTC with a signal rating of 47. The
> signal increases to 50 at 2030 UTC, but the path begins to fade
> between 2200-0030 UTC.
> 
> For today (although recent sunspot numbers are not as high) we don't
> see much chance of propagation until 1430 UTC with signal ratings
> gradually increasing from 43 to 45 at 1800, 47 at 1930, 50 at 2130,
> 52 at 2300, then fading after 0000 UTC.
> 
> A month from now we see poor prospects around the clock, with a
> D-rating (less than 25 percent chance) from 0430-0800 UTC, and
> C-rating (25-50 percent chance of opening) 0830-0400 UTC.  So the
> summertime propagation on 15 meters is much poorer than at the
> spring equinox.
> 
> If we look at much higher numbers, such as a sunspot number of 250
> instead of 130, we do see improvement, with several periods of B
> (50-75 percent) ratings.
> 
> K9LA has the W6ELprop software (for Windows) as well as tutorials
> available at his site, http://k9la.us/. If you want to guess what
> propagation might be like next month from your Field Day QTH to
> various targets around the United States, you could download the
> program and perhaps make an average of predicted solar flux over the
> weekend and several days prior, and plug that number into the
> program instead of sunspot number. See a daily update of predicted
> solar flux and planetary A index for the next 45 days at
> http://www.swpc.noaa.gov/ftpmenu/forecasts/45DF.html .
> 
> Let's hope for the best, an extension of this current solar cycle
> peak, rather than weakening and decline in solar activity.
> 
> For more information concerning radio propagation, see the ARRL
> Technical Information Service 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. More good
> information and tutorials on propagation are at http://k9la.us/.
> 
> 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 15 through 21 were 130, 136, 146, 138, 130,
> 126, and 100, with a mean of 129.4. 10.7 cm flux was 152.1, 138.7,
> 133.5, 127.5, 116.9, 117.2, and 113.9, with a mean of 128.5.
> Estimated planetary A indices were 5, 5, 4, 5, 4, 4, and 3, with a
> mean of 4.3.  Estimated mid-latitude A indices were 5, 6, 4, 5, 4,
> 4, and 3, with a mean of 4.4.
> NNNN
> /EX