[SFDXA] ARLP010 Propagation de K7RA

Fri Mar 6 22:51:58 EST 2015

> SB PROP @ ARL $ARLP010
> ARLP010 Propagation de K7RA
> 
> ZCZC AP10
> QST de W1AW  
> Propagation Forecast Bulletin 10  ARLP010
> From Tad Cook, K7RA
> Seattle, WA  March 6, 2015
> To all radio amateurs 
> 
> SB PROP ARL ARLP010
> ARLP010 Propagation de K7RA
> 
> Weakening sunspot activity continues. Average daily sunspot numbers
> dropped from 59 in the previous seven days to 54.1 during the week
> of February 26 through March 4.
> 
> Average daily solar flux actually rose a little, with values
> increasing from 116.3 to 122.9 over the same two weeks. In addition,
> on March 5 the noon reading for solar flux in Penticton was 140.2,
> but this was an outlier, reduced by NOAA to an official value of 130
> for the day.
> 
> The average daily sunspot number from December 1 through February 28
> was 98.2. This value centered on January 2015 adds to our archive of
> 3-month moving averages. According to our moving average, the cycle
> peaked in February and March 2014, with average daily sunspot
> numbers of 146.4 and 148.2. The February value was calculated by
> adding together all the daily sunspot numbers from January 1, 2014
> through March 31, 2014, then dividing by the number of days. The
> March value added all daily sunspot numbers from February 1 thought
> April 30. This smoothing makes it easier to spot peaks and trends.
> Since then the trend has been down in the past year.
> 
> Following February and March, the three month averages centered on
> April through December 2014 were 129.6, 118.4, 112.8, 109.2, 115.6,
> 108.4, 107, 104.7 and 107.8. From there it dropped to 98.2 for the
> recent period.
> 
> Don't forget, the vernal equinox is only two weeks away, and around
> this time the Northern and Southern Hemispheres are bathed in equal
> measures of solar radiation. We should enjoy enhanced HF radio
> propagation. Also, this weekend is the SSB portion of the ARRL
> International DX Contest. See http://www.arrl.org/arrl-dx for
> details. The outlook is good for the weekend.
> 
> Predicted solar flux from NOAA and USAF is 135 on March 6 and 7, 130
> on March 8 to 10, 135 on March 11 and 12, 130 on March 13 to 15, 135
> on March 16 and 17, then 130 and 125 on March 18 and 19 and 120 on
> March 20 and 21. Flux values then hit a minimum for the short term
> on March 24 and 25 at 110, then rise to 135 on April 12 and 13,
> according to the forecast.
> 
> The predicted flux values for March 6 to 12 are significantly higher
> than in the March 4 forecast, used in Thursday's edition of the ARRL
> Letter. Those reported values averaged to 121.4, while a day later
> the average value for the same period is 132.9. This indicates a
> temporary upward trend in the prediction.
> 
> Predicted planetary A index is 8 on March 6 to 8, then 12, 15, and
> 12 on March 9 to 11, then 8, 5, 8 and 5 on March 12 to 15, then 15
> on March 16 and 17, 8 on March 18, 5 on March 19 to 21, then 15, 20
> and 8 on March 22 to 24, 5 on March 25 and 26, then 15, 30, 25, 15
> and 10 on March 27 to 31, and 8 on April 1 to 4. The predicted
> planetary A index at 30 on March 26 is quite high, and is perhaps an
> echo of March 1 and 2 when the A index was 28. Over those same two
> days, the high latitude college A index at Fairbanks, Alaska was 36
> and 60.
> 
> According to Spaceweather.com on March 1 and 2 a solar wind brought
> aurora borealis to the Arctic Circle, and at 1530 UTC on March 2 an
> M3 class solar flare erupted, but was not aimed toward earth.  A
> blast of extreme ultra-violet radiation from the flare ionized the
> upper layer of Earth's atmosphere, causing a radio blackout below 10
> MHz.  This was most strongly evident over South America, as shown in
> this blackout map at
> http://spaceweather.com/images2015/02mar15/blackout.jpg .
> 
> Petr Kolman, OK1MGW predicts mostly quiet geomagnetic conditions on
> March 6 and 7, quiet to unsettled March 8 to 10, quiet March 11 to
> 13, mostly quiet March 14, quiet to unsettled March 15, quiet to
> active March 16 to 18, mostly quiet March 19 and 20, quiet to
> unsettled March 21, quiet to active March 22, active to disturbed
> March 23, quiet to unsettled March 24, mostly quiet March 25 and 26,
> quiet to unsettled March 27, active to disturbed March 28 and 29,
> and quiet to unsettled again on March 30 and 31.
> 
> Robert Elek, W3HKK of Johnstown, Ohio wrote:
> 
> "Had fun chasing 3G0ZC around the bands with my KW to assorted wire
> antennas from here in central Ohio. 10, 12, 15, 17, 80, 40, 30 and
> 20 meter contacts were put in the log (5 bands on one afternoon
> alone!) but 160 eluded me.
> 
> Heard them twice (both nights of the 160M SSB contest) but QRM was
> brutal at my end from the SSB boys. I slept through the next night's
> 160 meter window (I heard they peaked nicely between 5:45-6 am EST
> then disappeared) but stood guard the final two nights between
> 5:30-6 am but heard nothing from them, or anyone else calling them,
> for that matter. Read they had bad generator noise (and maybe QRN?)
> that limited them to just 76 QSOs on Top Band.  Bummer.
> 
> Fast forward to 4-5 March. After working through the 3G0ZC pile ups
> for Robinson Caruso Island, I was happy to just casually listen
> around the bands while puttering in the (spare bedroom) shack, and
> between trips to watch TV with the XYL. Bands seemed unusually quiet
> - free from QRN and QRM. Frankly, not a lot coming through.
> 
> Then began an amazing sequence of QSOs. At 2357z on 4 March I worked
> JY4NE on 20 CW with his nice signal. Then a few minutes later added
> JT1CO on 17 meter CW at 0010z on 5 March, and E51UFF at 0020z on 10
> CW.  Then JW9JKA on 20 CW at 0032z. Wow. The Middle East, Mongolia,
> the S. Cook Islands in the South Pacific, and Arctic Europe all in a
> span of 35 minutes - without the benefit of a beam antenna!
> 
> I took a couple hour break watching TV, happy with a very nice
> world-wide string of FB DX.
> 
> Then from 0500-0612z another string began. TR8CA on 40 CW at 0500z;
> then I dropped down to 160 and heard very little. But all of a
> sudden TI5/KL9A went into the log at a very solid 579 at 0513z; then
> as I poked around the quiet band there was KH6AT also 579 (at his
> sunset, no less!) calling CQ at 0539z; and at 0550Z I heard DK2CF at
> 569 calling CQ.
> 
> I decided it was time to move back to 40 meters and see what was
> happening there. At 0610z V73NS in the Marshall Islands was calling
> CQ just above the noise. It was still daylight there, maybe 2 hours
> before their sunset and he was coming through. And finally at 0612z
> here comes E51UFF from the S. Cook islands again.
> 
> I had just enjoyed a feast of worldwide DX during about 90 minutes
> of casual operating, covering 10, 17, 20, 40 and 160 meters. I
> scanned 40 SSB and heard about a dozen EU and Russian DX stations
> including a YL from Moldova who was attracting a crowd, several of
> the LZ boys, etc., but nothing new DX-wise, so I pulled the switch
> and went to bed.
> 
> This was one of those unexpected and very warm, fuzzy periods of
> operating that you don't forget, because the propagation gods were
> smiling."
> 
> Excellent! Thanks for the report. In a subsequent email, W3HKK
> continued:
> 
> "Tad, I've been reading up on ON4UNs Low Band DXing book and noticed
> his comments about 'spotlight' propagation especially on 160 meters.
> That perfectly describes several recent contacts on that band with a
> KH6, a near contact with a CX6 tonight, and with a couple of
> Europeans.
> 
> Nobody is coming through on the band. Then all of a sudden one or
> two DX signals are very good copy but nobody is responding to their
> CQs, so I jump in and work him. He then goes back to CQing with only
> the occasional taker. Ditto with Europe. No European activity. Then
> a couple of HA's are fairly strong for a while, but have few takers.
> Isolated strong signals for a period of time from SA, Europe, and
> the Pacific.
> 
> 60 meters has been exploding with DX. With the 100 watt limit now,
> and more countries getting on board, 60 meters has been a gold mine
> of DX here of late. Tonight alone I worked 4Z4, GW0, ZD8, and LB6.
> Imagine that! LZ, OH, K1N, HI8, CY0 and V47 were other 60 meter
> contacts during February.
> 
> This new 8 direction SAL-30 receiving antenna is letting me see
> where signals are coming from as well as providing a nice 20 dB or
> so F/B on LF, broadcast band, and 160, 80, 60 and 40 meters. It's a
> joy to have on the low bands."
> 
> You can read more about his all-wire antennas and his new receiving
> antenna by logging into QRZ.com, then go to
> http://www.qrz.com/db/w3hkk .
> 
> The Robinson Crusoe Island operation (which ended on March 4) has a
> neat propagation tool on their web site at
> http://juanfernandez2015.com/?page_id=1063 .
> 
> Several readers, including AB1DD have mentioned spaceweather.tv
> recently, with videos by Dr. Tamitha Skov explaining solar
> phenomena. Check out http://spaceweather.tv/ ,
> http://spaceweather.tv/blog/ and
> http://spaceweather.tv/category/solar-forecast-outlook/ . She also
> has a channel at https://www.youtube.com/user/SpWxfx .
> 
> 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 February 26 through March 4 were 39, 58, 70, 66,
> 65, 38, and 43, with a mean of 54.1. 10.7 cm flux was 111.3, 118,
> 123.4, 127.6, 130.4, 125.1, and 124.2, with a mean of 122.9.
> Estimated planetary A indices were 5, 4, 13, 28, 28, 11, and 10,
> with a mean of 14.1.  Estimated mid-latitude A indices were 5, 2,
> 11, 23, 18, 10, and 9, with a mean of 11.1.
> NNNN
> /EX
>