SB PROP @ ARL $ARLP009

ARLP009 Propagation de K7RA

ZCZC AP09

QST de W1AW

Propagation Forecast Bulletin 9 ARLP009

From Tad Cook, K7RA

Seattle, WA March 1, 2013

To all radio amateurs

SB PROP ARL ARLP009

ARLP009 Propagation de K7RA

Solar and geomagnetic activity over the past week (Thursday through

Wednesday, February 21-27) declined, with the average daily sunspot

number dropping nearly 21 points to 57.7. Average daily solar flux

softened by 4.7 points to 100.9, and average daily planetary A index

declined 6.4 points to 5.1. This isn't much of a change, but

geomagnetic activity was low already, and this is even lower.

Predicted solar flux for the near term is 110 on March 1-3, 105 on

March 4-7, 100 on March 8, 95 on March 9-14, 100 on March 15-16, 105

on March 17, and 110 on March 18-20. Solar flux then reaches a peak

of 120 on March 25-27, and on March 28 through April 6 maintains an

average around 113.

The predicted planetary A index is 12 and 8 March 1-2, 5 on March

3-4, 8 on March 5, 7 on March 6-7, 5 on March 8-10, 7 on March

11-12, and 5 on March 13-20.

OK1HH predicts quiet to active geomagnetic conditions on March 1,

mostly quite March 2, quiet to unsettled March 3, quiet on March 4,

mostly quiet March 5, quiet to unsettled March 6, quiet to active

March 7, quiet on March 8, mostly quiet March 9-10, quiet to active

March 11-12, quiet to unsettled March 13-16, mostly quiet March

17-18, quiet to unsettled March 19-21, active to disturbed March 22

and quiet on March 23-24.

It is interesting to note that OK1HH predicts active to disturbed

conditions on March 22, but NOAA and USAF predict a benign planetary

A index of only 5 on that date.

This weekend is the ARRL International Phone DX Contest, from March

2, 0000z to March 3, 2400z. If you are on the West Coast, and use

Pacific Standard Time, that would begin at 4:00 PM on Friday, ending

at 4:00 PM on Sunday. For more info, check

http://www.arrl.org/arrl-dx.

With February ended, let's look at some updated averages. Our most

recent 3-month moving average does not impress. The three months

centered on January 2013 had an average daily sunspot number of

73.6. This is below every three-month moving average for last year,

except the three months centered on March 2012, which was 71.2. The

3-month moving averages of daily sunspot numbers centered on January

2012 through January 2013 were 83.3, 73.7, 71.2, 87.3, 91.5, 96.5,

91.9, 89.9, 81.2, 82.3, 74.4, 82.8 and 73.6.

Jim Henderson, KF7E sent a link to an impressive NASA clip of solar

activity from last July. Note that you can set this video to HD

resolution, and it looks great on full screen. See it at

http://apod.nasa.gov/apod/ap130226.html.

Also check out the photo gallery of solar events at

http://news.cnet.com/2300-11386_3-10015988.html and note the

dramatic composite image number 4.

Walt Knodle, W7VS sent an article about artificial ionosphere

produced by the HAARP facility in Alaska with a 3.6 megawatt signal

on 69 meters. Note that they are only able to produce the effect

for 45 seconds. Read about it at

http://phys.org/news/2013-02-scientists-densest-artificial-ionospheric-plasma.html.

I think the Wikipedia page at

http://en.wikipedia.org/wiki/High_Frequency_Active_Auroral_Research_Program

gives a pretty good overview of the HAARP project.

Also the September 1996 issue of QST has a nice article by K3NS

titled, "The High Frequency Active Auroral Research Program." ARRL

members can find and download it from the ARRL website with a search

at http://www.arrl.org/arrl-periodicals-archive-search.

Jim Smith, K3RTU operated on HF CW from Ridley Creek State Park in

Southeast Pennsylvania (FM29) on February 25. He wrote, "I hooked up

with EA8BVP in the Canary Islands. 'Bal' EA8BVP was using a FT-817

and a vertical, and I was using my FT-817 and my trusty Buddistick

vertical. This CW QSO took place early in the afternoon on 18.086

MHz. I had been trying to make a contact on 20 meters and was having

no luck so I QSYed to 17 meters and almost within minutes heard

EA8BVP calling CQ. Both of our signal levels were S4 to S5. I

frequently operate on 17 meter CW while out backpacking and more

often than not it provides me with good long distance contacts."

It looks like the path from the park to the Canary Islands would be

good in the early afternoon, with the best 17 meter signals that day

from 1200-2200 UTC. 17 meters does look like a better bet, with 20

meters not catching up until after 2000 UTC.

If you would like to make a comment or have a tip for our readers,

email the author at, k7ra@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://myplace.frontier.com/~k9la/.

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 21 through 27 were 75, 79, 56, 25, 59,

49, and 61, with a mean of 57.7. 10.7 cm flux was 108.5, 107, 99.6,

94.9, 95.4, 98.7, and 102, with a mean of 100.9. Estimated planetary

A indices were 6, 9, 6, 3, 3, 5, and 4, with a mean of 5.1.

Estimated mid-latitude A indices were 5, 9, 6, 2, 3, 4, and 4, with

a mean of 4.7.

NNNN

/EX