[SFDXA] ARLP034 Propagation de K7RA

Fri Aug 23 17:25:23 EDT 2013

> SB PROP @ ARL $ARLP034
> ARLP034 Propagation de K7RA
> 
> ZCZC AP34
> QST de W1AW  
> Propagation Forecast Bulletin 34  ARLP034
> From Tad Cook, K7RA
> Seattle, WA  August 23, 2013
> To all radio amateurs 
> 
> SB PROP ARL ARLP034
> ARLP034 Propagation de K7RA
> 
> Solar activity picked up this week, with average daily sunspot
> numbers for August 15-21 up nearly 42 points (forty-nine percent) to
> 126.9, when compared to the previous seven days.  Likewise, average
> daily solar flux increased from 111.7 to 126.3.
> 
> The latest prediction from USAF/NOAA has solar flux at 130, 125,
> 120, and 115 on August 23-26, 110 on August 27-29, 105 on August 30,
> 95 on August 31 through September 1, 100 on September 2, 105 on
> September 3-4, 110 on September 5-8, 115 on September 9-11, 120 on
> September 12-13, and 125 on September 14-16. It then drops below 100
> to 95 again on September 27-28.
> 
> Predicted planetary A index is 15, 25, 20, 12, and 8 on August
> 23-27, 5 on August 28-30, then 12, 15 and 10 on August 31 through
> September 2, 5 on September 3-9, then 10, 15 and 18 on September
> 10-12, 8 on September 13-14, then 5, 15, 22, 12 and 8 on September
> 15-19 and 5 on September 20-26.
> 
> OK1HH predicts in his geomagnetic activity forecast that August
> 23-24 will be active to disturbed, quiet to active conditions on
> August 25, quiet to unsettled August 26, mostly quiet August 27-29,
> quiet August 30, active to disturbed August 31 and September 1,
> quiet to unsettled September 2, quiet September 3-5, mostly quiet
> September 6-7, quiet September 8-9, quiet to active September 10-11,
> active to disturbed September 12-13, quiet September 14, mostly
> quiet September 15, quiet September 16, quiet to active September 17
> and active to disturbed September 18.
> 
> On Saturday, August 17, 2013 the Penticton observatory recorded
> solar flux values of 123.2, 149.7 and 129 at 1700, 2000 and 2300
> UTC. The local noon value at 2000 UTC is always reported as the
> official flux value for the day, but NOAA reported it as 125 instead
> of 149.7.  They do this when the noon number appears to be an
> outlier caused by overload of the 2.8 GHz receiver used to produce
> these numbers. I suspect the overload was caused by a significant
> and long duration M3 class solar flare, erupting from sunspot 1818
> at 1824 UTC.
> 
> The NOAA estimate is produced by selecting a number somewhere
> between the morning and afternoon readings.
> 
> A look at the weekly Preliminary Report and Forecast for August 5,
> 2013 (see http://www.swpc.noaa.gov/weekly/pdf/prf1979.pdf) shows the
> most recent prediction for smoothed sunspot numbers peaking in
> January and February 2014.
> 
> The Arizona Daily Star ran an interview with Matt Penn, the
> astronomer who predicted the possible disappearance of future
> sunspots based on weakening solar magnetic fields. Read it at 
> http://azstarnet.com/news/science/don-t-flip-out-about-the-sun/article_ce93e4cf-0178-51bf-882e-fee8e5e8de91.html.
> 
> David Dary, W5ZAX of Norman, Oklahoma sent in an interesting article
> about a different method for tracking the complexity of the solar
> magnetic field. It posits that the sun may be more active than it
> appears. Read it at 
> http://www.universetoday.com/104023/is-the-sun-more-active-than-it-looks-an-innovative-method-to-characterize-the-solar-cycle/.
> 
> Note they give a link to the original journal article. You may be
> able to access the article in the Astrophysical Journal online for
> free via an account at your local public library.
> 
> Roland Anders, K3RA of Elkridge, Maryland reports on August 19: "15
> meters continues to be fantastic into Indonesia from 8 am until past
> 1 pm EDST. Besides the many strong YB stations, in the past several
> days during the 1300 to 1745Z time period on 15 I've worked JA, BY,
> BV, 9M2, 9M4, V8, 9V, HS, 4S, VU, and UN. And the EU signals are
> crushingly loud! But when 15 is that good to EU, it is a clue to try
> 12 meters. I've found 12 open in the morning hours several times in
> the last week. Today, I called CQ on 12 (dead band) and worked 2 IT9
> stations at 12:45Z. After some more CQs with no answers, I returned
> to 15. I'm sure 12 was open to EU from time to time during the
> morning -- maybe all morning, but I didn't get back to 12 until
> 1612Z."
> 
> "For the next hour I worked DX over a wide area: Starting with a
> walloping signal from CU8AS, I then worked stations as far North as
> TF and east to SV and HZ. But the biggest surprise was at 1644 when
> I worked YB0NFL S9 over the North Pole. Arif worked a lot of EU and
> NA DX over the half hour or so--that's 12 meters at midnight Jakarta
> time! And, there were a couple of EU stations heard on 10 meters
> when 12 was open. So, it seems like we're getting into fall
> conditions on 12 and 10 meters. This much maligned sunspot cycle has
> a lot to offer!"
> 
> Later he wrote: "Went back to 12 meters at 2100Z, and the band was
> wide open to EU. Some stations VERY loud. Then, at 2130Z I heard JAs
> answering an LU CQ, so I call CQ with beam to JA and worked seven
> JAs, several very strong. Viva 12!"
> 
> Laurence, GJ3RAX from the Isle of Jersey sent this in: "I have been
> following the discussions on this solar cycle and the question of
> whether there will be a second peak. Looking at the graphs of the
> previous ones I interpret them as all having a second peak even if
> it is not as well defined as in the more recent 2 cycles. Obviously
> the graphs do show that the second peak is normally weaker than the
> first one. The shape of the present one looks as if that trend is
> going to be followed although it is often dangerous to make such
> assumptions."
> 
> "You have probably seen the same predictions that I have suggesting
> that Cycle 25 will be even weaker and some think it could be
> virtually flat. Looking at the historical information it does seem
> to do that about every 100 years."
> 
> "The conditions on the HF bands have been so poor with my rather
> minimal antenna system that I have not been able to resume skeds
> with my friends in the USA and Canada. Those used to be mainly on 17
> meters. Instead we have been catching up in person when some of my
> friends have come over here to visit me! That is partly why I have
> now gone back on the VHF and UHF bands instead."
> 
> "From what I can recollect of the recent cycles I think that the
> best conditions each time on the 6 meter band have been during the
> second peak rather than during the first one. This year I have been
> using a rather low gain log periodic antenna covering 50 MHz to
> 1,300 MHz. Photos are on my QRZ.com entry. I have had QSOs with 39
> countries on 6 meters so far this year and all were on SSB. I keep
> thinking I should learn Morse or try some of the digital modes. Most
> of those have been within Europe and North Africa (EA8, EA9 and
> CT3). On the second of this month I was on during the only
> transatlantic opening I have caught this year. I worked VE1YX and
> five in the USA. My radio on 6 meters is the IC-756 Pro 2."
> 
> "A few weeks ago I got back on the 4 meter band after an absence of
> about 30 years. There are now many more countries on the band than
> when I was first on. My score this year is now 11 countries although
> I could have got a lot more if I had been on earlier in the Sporadic
> E season. I am using a Spectrum transverter, with 20 watts out,
> driven by an FT-817."
> 
> "On 2 meters I have had 9 countries, 70 cms 7 countries and 23 cms 5
> countries this year all using an IC-910X. Last year I was able to
> work into Germany on all three of those bands during November when I
> had just got back on those bands. I have worked Germany this year on
> 2 meters. I am hoping to be able to get more on the list when the
> Tropo season starts which is usually in October."
> 
> "Earlier this year I joined the Yahoo group for the microwave bands,
> http://groups.yahoo.com/group/ukmicrowaves/ . That one is very
> interesting but I later realized that I could not find a suitable
> one for the lower VHF and UHF bands so I recently started one -
> http://groups.yahoo.com/group/VHFandUHF/ . That group now has 69
> members and seems to be growing nicely. We already have 3 members in
> the USA so maybe we will get more from your part of the world soon."
> 
> Thanks, Laurence! Many readers may be unfamiliar with the 4 meter
> amateur band at 70 MHz, which is used in Europe but not North
> America. Some links to information on 4 meters:
> http://en.wikipedia.org/wiki/4-meter_band, http://www.70mhz.org/,
> and http://g1efu.webs.com/4meters.htm.
> 
> 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 August 15 through 21 were 129, 104, 96, 134,
> 161, 115, and 149, with a mean of 126.9. 10.7 cm flux was 122.7,
> 119.9, 125, 126.1, 128.3, 131.5, and 130.4, with a mean of 126.3.
> Estimated planetary A indices were 15, 23, 7, 6, 5, 5, and 18, with
> a mean of 11.3.  Estimated mid-latitude A indices were 15, 27, 9, 8,
> 6, 5, and 13, with a mean of 11.9.
> NNNN
> /EX