[South Florida DX Association] ARLP019 Propagation de K7RA

[Bill Marx]

> 
> ZCZC AP19
> QST de W1AW  
> Propagation Forecast Bulletin 19  ARLP019
> From Tad Cook, K7RA
> Seattle, WA  May 13, 2011
> To all radio amateurs 
> 
> SB PROP ARL ARLP019
> ARLP019 Propagation de K7RA
> 
> As reported in the ARRL Letter, on Wednesday May 11 six sunspot
> groups were visible, but that number shrunk to two on Thursday.
> Daily sunspot numbers declined from 84 to 29 over those two days as
> well, but the average sunspot number for the reporting week
> (Thursday, May 5 through Wednesday, May 11) grew by nearly 7 points
> from last week to 74.6.
> 
> The latest forecast shows planetary A index of 10 for today, May 13,
> then 8 on May 14-16, 10 on May 17, 8 on May 18, and 5 on May 19-25.
> The next possibly big geomagnetic period is May 27, with a planetary
> A index of 22.
> 
> The same forecast predicts solar flux of 95 on May 13-14, 90 on May
> 15-19, and 110 on May 20-30.
> 
> Geophysical Institute Prague predicts quiet to unsettled conditions
> May 13, quiet May 14, quiet to unsettled May 15, unsettled May
> 16-18, and quiet to unsettled again on May 19.
> 
> On May 9 NASA released a slightly revised prediction for the peak of
> Cycle 24, placing it at a smoothed sunspot number of 69 in June
> 2013.  But a month earlier the estimate had a peak of 62 in July
> 2013.  Last month NASA was predicting this cycle as the weakest in
> 200 years, but the update places it as the weakest in the last
> century.
> 
> These are Zurich sunspot numbers, which are always quite a bit lower
> than the NOAA SESC numbers that we report here.  The NOAA numbers
> show a peak at 90 around February through July 2013.
> 
> On May 10, Rol Anders, K3RA of Elkridge, Maryland wrote, "After a
> slow week or so, propagation has rebounded with extremely strong
> signals from Europe and Central Asia on 20 meters for several hours
> after their sunrise time. Many 30 and 40 dB over signals heard in
> Maryland.  I think there have been a lot of tardy arrivals at work
> in EU and Central Asia as the hams have had difficulty pulling
> themselves away from such great conditions in the morning! Also, 17
> meters has been very good in the evening with JAs and other Asian
> stations coming back to CQs 3 hours after sunset on the East Coast.
> 15 meters has been open to the Far East after sunset as well.  Most
> interesting was working JQ1QKK short path on 20 meter phone at 3 pm
> his time, 2 AM east coast time!
> 
> "One 'trick' that I sometimes use to find openings is to look for
> 'analogous openings' at my latitude. If I can work a DX station
> close to my latitude at a certain time of the day, then it is likely
> that I'll be able to work stations at that latitude the same
> distance away in the other direction when my local time is the same
> as that first DX station's was. Perhaps this is best explained by an
> example: the latitudes of JA and EX/EY/EZ/YA are not too different
> from Maryland, and they are both roughly the same distance away from
> me.  So, if JQ1QKK in the example above was working me at 3 pm his
> time (2 am my time), there should be an opening to the general
> EX/EY/EZ area from MD at 3 pm my time, 2 am EX/EY/EX time. This can
> be extended to other latitudes if you know what DX stations at your
> latitude are working. For instance, if I hear stations at my rough
> latitude (EA, I, SV, EX, JA) working a path, I should have that same
> path when my local time is the same as theirs was when they
> experienced those paths. Of course, my path will be to an entirely
> different part of the world."
> 
> Mark Bell, K3MSB of Airville, Pennsylvania wrote, "Had some nice 6M
> sporadic-E action here around May 3. Worked YV4DYJ in FK50 at 2253Z.
> Stations from LU were coming in quite strong the next two days."
> 
> N0JK reports from Kansas that on May 5 he worked LU4FW on 6 meters
> with a sporadic-E trans-equatorial link. It was at 2138z, and he was
> using an indoor dipole.
> 
> Rich Molinski, WB2KWF of Smithfield, Virginia reported from FM16qw
> that on May 2 he worked 9Y4D and YV4DYJ on 6 meters using 80 watts
> and a 3 element beam at 35 feet, with 5x3 reports each way.  On May
> 6 he reported, "I was amazed at the propagation! It's nice to see 6m
> open up. Each night this week, 6 has been open to some degree."
> 
> Bob Elek, W3HKK in central Ohio reports an E-skip opening on May 5
> on 6 meters. He reports, "A C6 was 59+20 and had half the US calling
> him on SSB.  Then for the first time in my 55 year ham radio career:
> TE skip to Argentina!  (Interestingly I had just finished reading
> the VHF column in CQ Magazine describing how May was the poorest
> month for TE skip and not to expect it.) Well, around dinner time in
> Ohio, on May 5th there it was. The 6M band literally teeming with
> Argentine stations, mostly on SSB, from 50.1 to 50.13 MHz.  LU after
> LU working pile ups, calling CQ, and coming in between 5x3 to 5x9
> (on my 5 el Yagi, 10 ft above my rear patio, equipped with the
> standard Armstrong rotator, and fed by an IC7600 100w rig).
> 
> "At 2125z I worked LW3EX on 50.101 CW, then at 2133 9Y4VUX on 50.100
> CW, and then at 2200z LU9EEM on 50.120 SSB, all with sigs between 57
> and 59! In between I tuned around for other countries and passed up
> on many LUs. Another local op worked the VP8 (Falkland Islands), and
> a couple spots showed one station in OA and CE coming through but I
> didn't hear them.
> 
> "So, in summary, a very telescopic opening via TE into Argentina lit
> up 6M, and when things quieted down at around 2230z, I left for
> dinner a little late but a very happy camper."
> 
> Roger Gibson, K4KLK of Raleigh, North Carolina (in FM05) reports,
> "Six was open all day May 5 to WI area and then FL. I was surprised
> to hear LU4FW FF97 on halo antenna in garage. I quickly turned
> antenna south then connected the 4 El Quad 20 feet up and got him on
> first call with 100 watts. Not many takers but signal was very
> strong 59+ more like F2 and no fading. Contact made on 50.125 SSB at
> 2200Z. He was in for several minutes."
> 
> Both K5LJ and N4ZQ wonder why it seems that most sunspots appear in
> the Sun's northern hemisphere so far in this cycle.  I ran this by
> K9LA who says, "Hemispherical asymmetry of sunspots has been known
> and studied for quite a while. I don't think there's an air-tight
> explanation yet, but it is tied to the Sun's conveyor belt.  So
> what's happening now is 'normal' in the sense that it's been seen
> before in other cycles."  He noted that butterfly diagrams of Cycle
> 20 show this predominance toward the beginning of the cycle, around
> 1965.
> 
> 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, see the ARRL
> Technical Information Service web page 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. Find more good
> information and tutorials on propagation at
> http://mysite.ncnetwork.net/k9la/index.html.
> 
> 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 5 through 11 were 95, 71, 38, 61, 93, 80,
> and 84, with a mean of 74.6. 10.7 cm flux was 104.9, 101.9, 102.2,
> 102.2, 103.7, 97.5, and 94.1, with a mean of 100.9. Estimated
> planetary A indices were 7, 4, 4, 2, 3, 8, and 6, with a mean of
> 4.9. Estimated mid-latitude A indices were 5, 3, 3, 0, 2, 5, and 7,
> with a mean of 3.6.
> NNNN
> /EX