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ARRL Propagation Bulletin ARLP009 (2007)

ARLP009 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 9  ARLP009
From Tad Cook, K7RA
Seattle, WA  February 23, 2007
To all radio amateurs 

ARLP009 Propagation de K7RA

Sunspot numbers picked up a bit this week from 0 daily sunspot
numbers for February 11-15. Currently the sunspot number is 25 for
February 22, with only a lone visible spot, small sunspot 942,
looking straight at us from the center of the visible solar disk.

Average daily sunspot numbers for our most recent reporting week
(February 15-21) rose over eight points from the previous week to
14.6. Average daily solar flux was nearly unchanged, from 75 to

Look for sunspot numbers and solar flux to rise over the next few
days. Predicted solar flux for February 23-26 is 78, 80, 85 and 85.
The predicted Planetary A index over the same period is 5, 5, 25 and
15. The Australian Space Forecast Centre predicts possible minor
geomagnetic storms on Sunday, February 25. Geophysical Institute
Prague predicts quiet to unsettled conditions for today, February
23, quiet conditions on February 24, active conditions February
25-26, unsettled to active on February 27, and unsettled for
February 28.

Billy Michaud, AA1TT in Claremont New Hampshire operates a 5 watt
10-meter beacon on 28.269 MHz in grid square FN33uj. On February 14
Billy received a report from Ned Conklin, KH7JJ in Honolulu, that
Billy's beacon was received with good signals at 2100z. Ned operates
exclusively on 10-meters using a mobile whip clamped to the railing
of his apartment's lanai railing. Ned says this is the first
10-meter beacon from the Eastern USA that he's heard in 2 years.
Billy reports that with the sunspot cycle at the bottom, he doesn't
get many reception reports for his beacon lately, except for some
sporadic E propagation. Billy has a web page devoted to his beacon

Mike Best, WD4DUG sent an article from Toronto's Globe and Mail
about five satellites recently launched to study aurora. View it at, David Moore sent an interesting article
from the European Space Agency about the Ulysses spacecraft
observing the sun. You can read about it at,

If you would like to make a comment or have a tip for our readers,
email the author at,

For more information concerning radio propagation, see the ARRL
Technical Information Service at, For a detailed
explanation of the numbers used in this bulletin see, An archive of past
propagation bulletins is at, Monthly
propagation charts between four USA regions and twelve overseas
locations are at,

Sunspot numbers for February 15 through 21 were 0, 12, 11, 12, 26,
27 and 14 with a mean of 14.6. 10.7 cm flux was 73.6, 74.7, 75.3,
75.8, 74.9, 74.7, and 74.8, with a mean of 74.8. Estimated planetary
A indices were 11, 6, 8, 5, 3, 2 and 1 with a mean of 5.1. Estimated
mid-latitude A indices were 15, 6, 7, 3, 2, 1 and 1, with a mean of


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