[SFDXA] ARLP034 Propagation de K7RA

Bill bmarx at bellsouth.net
Fri Aug 21 20:54:25 EDT 2020


> 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 21, 2020
> To all radio amateurs 
> 
> SB PROP ARL ARLP034
> ARLP034 Propagation de K7RA
> 
> Sunspots disappeared during four days over the past week, but then
> came back.  Average daily sunspot number declined from 14.3 to 5.4,
> while average daily solar flux went from 73.8 to 71.
> 
> Geomagnetic indicators remain quiet.  Average daily planetary A
> index increased from 3.7 to 4.4.
> 
> Predicted solar flux is 70 on August 21 and 22, 69 on August 23 to
> 28, 72 on August 29, 73 on August 30 to September 5, 72 on September
> 6 to 9, 71 on September 10 and 11, 70 on September 12 to 19, 71 on
> September 20 o 23, 72 on September 24 and 25, 73 on September 26 to
> October 2, and 72 on October 3 and 4.
> 
> Predicted planetary A index is 5 on August 21 and 22, 6 on August 23
> to 25, 5 on August 26 to 28, 8, 16 and 8 on August 29 to 31, then 5
> on September 1 to 14, 10 on September 15 and 16, 5 on September 17
> to 24, then 8, 16 and 8 on September 25 to 27, and 5 on September 28
> to October 4.
> 
> Geomagnetic activity forecast for the period August 21 to September
> 16, 2020 from F. K. Janda, OK1HH.
> 
> "Geomagnetic field will be 
> Quiet on: September 5 to 7 
> Quiet to unsettled on: August 22, (23,) 24 and 25, (26 to 28,)
> September 2 to 4, 8 and 9
> Quiet to active on: (August 21, 29 to 31, September 1, 16) 
> Unsettled to active: not expected  
> Active to disturbed: not expected  
> 
> Solar wind will intensify on: August (21 to 23,) 24 and 25, 29,
> September 1 and 2, (4 to 6,) 8, 15 and 16
> 
> Remarks:  
> - Parenthesis means lower probability of activity enhancement."  
> - Next Geomagnetic activity forecast will be issued on 3rd
> September, so it must be time for OK1HH to take his annual vacation.
> 
> Thanks to Max White for this link to an article about a dent in
> Earth's magnetic field and the South Atlantic Anomaly:
> 
> https://bit.ly/2Qbmw9R
> 
> The latest report from Tamitha Skov, WX6SWW, the Space Weather
> Woman:
> 
> https://youtu.be/GW4HOvejxFA
> 
> The CME she spoke of turned out not to be geo-effective, so we
> missed a disturbance.
> 
> From reader David Moore, info on the NASA THEMIS Mission:
> 
> "A special type of aurora, draped east-west across the night sky
> like a glowing pearl necklace, is helping scientists better
> understand the science of auroras and their powerful drivers out in
> space."
> 
> https://bit.ly/2QeRU78
> 
> George Hall, N2CG wrote:
> 
> "Reading The K7RA Solar Update 08/14/2020 issue of your personal
> experience of solar Cycle 19 when you were a young boy with your dad
> listening to the low band VHF FM 2-Way radio in your dad's company
> car in California and suddenly hearing stations in Texas and other
> Midwestern states brought back fond memories of a similar nature I
> experienced in Solar Cycle 20.
> 
> I was a Radioman on active duty in the USCG stationed at Coast Guard
> Radio Station NIK/NJN located on the U.S. Naval Air Station
> Argentia, Newfoundland CANADA.  One day the Crash Crew (a fire
> department specifically devoted to incidents on the airport with
> specially equipped fire trucks that could literally drive right up
> on top of a fire on the ground and expel fire extinguishing foam
> from the underside of the crash crew trucks to put out the fire).
> 
> The Crash Crew was a 24/7/365 operation and monitored the airport
> control tower's VHF Low Band (I don't remember the frequency but it
> was VHF Low Band between 30 to 49 MHz).  One bright sunny early
> afternoon in June 1968 all of a sudden over the radio came the loud
> and clear call "ROLL THE GEAR" "ROLL THE GEAR" which is the highest
> response precedence for the Crash Crew to man the crash crew trucks
> and head for the airport crash site.
> 
> So, without hesitation the Argentia Newfoundland Crash Crew
> immediately manned the crash crew trucks and headed for the airport
> except they saw no evidence of a crash.  There was no smoke or fire.
> The senior on-scene crash crew member called the tower and asked if
> this was a drill?  The tower replied they also heard the "ROLL THE
> GEAR" call but it was not them and for the crash crew to return to
> station.
> 
> Later that day it was determined that the "ROLL THE GEAR" call was
> actually from the U.S. Naval Air Station in Rota, Spain, over 2,500
> miles away!  Both Argentia and Rota used the same VHF Low Band
> frequency.
> 
> Thanks for bringing back the fond memories of over 52 years ago."
> 
> For more information concerning radio propagation, see
> http://www.arrl.org/propagation and the ARRL Technical Information
> Service at http://arrl.org/propagation-of-rf-signals.  For an
> explanation of 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/.
> 
> Instructions for starting or ending email distribution of ARRL
> bulletins are at http://arrl.org/bulletins.
> 
> Sunspot numbers for August 13 through 19, 2020 were 11, 0, 0, 0, 0,
> 12, and 15, with a mean of 5.4.  10.7 cm flux was 72.3, 70.8, 70.6,
> 70.9, 70.8, 71.3, and 70.5, with a mean of 71.  Estimated planetary
> A indices were 4, 4, 3, 4, 3, 7, and 6, with a mean of 4.4.  Middle
> latitude A index was 5, 3, 3, 5, 3, 7, and 9, with a mean of 5.
> NNNN
> /EX



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