ARRL

ARRL Propagation Bulletin ARLP053 (2001)

SB PROP @ ARL $ARLP053
ARLP053 Propagation de K7VVV

ZCZC AP53
QST de W1AW  
Propagation Forecast Bulletin 53  ARLP053
From Tad Cook, K7VVV
Seattle, WA  December 14, 2001
To all radio amateurs 

SB PROP ARL ARLP053
ARLP053 Propagation de K7VVV

This has been another relatively quiet week with little in the way
of geomagnetic upset. Planetary A indices were in the single digits
through Tuesday. On Wednesday the planetary K index went to 5, which
is quite high, but then quieted back down.

A powerful solar flare erupted on Tuesday, but the resulting coronal
mass ejection is not earth-directed. It could cause an upset
starting Friday, and so the predicted planetary A index for Friday
through Monday is 15, 20, 25 and 10.

Average sunspot numbers dropped this week by over 16 points, and
average solar flux was down by almost 3 points. Solar flux is
expected to decline, with Friday through Monday values around 220,
220, 210 and 200, and should reach a short term minimum around
December 22-23.

Geomagnetic disturbances could cause problems for the ARRL 10-Meter
Contest this weekend, but the effect is difficult to gauge at this
point.

Recent 6 Meter excitement prompted Rich Zwirko, K1HTV to send in a
report. We won't attempt to summarize, since Rich communicates such
excitement over his activities on 6 Meters. Rich wrote, ''I just thought
I'd let you know how things are going from the mid-Atlantic area on
50 MHz. Although I've on the air with this K1HTV call since 1958,
I've only operated 6 Meters in the tail end of Cycle 21 in 1981,
Cycle 22 (89-91) and the present Cycle 23. Although the last solar
cycle with its double peak was a great one for 6 Meter DX, this one
(also with a double peak) is even greater. Part of it is because
there are more off-the-shelf rigs with 6 Meters in them, part of it
is because so many countries in Europe have freed 50 MHz from TV
use.

''On 6 Meters I run about 150 Watts output to a 6-element Yagi on the
roof, 30 feet above the ground. The K1HTV QTH in Glenn Dale,
Maryland is about 12 miles northeast of the White House. To give you
an idea of how good the conditions have been here, I've listed below
the 74 countries worked so far this year on 6 Meters, 70 of them
worked since October 21!

''The prefixes of the 70 countries worked, in the order they are
listed are W, VE, VP8 (Falklands), LU, PY, KP4, C6A, GM, PA, G, ON,
GW, DL, OK, GI, GM, CO, EA8, YV, VP5, EA, CT, VP9, GB, YU, CU, E3,
EA9, PY0, EI, I, 9H, OH, HK, 9Y, FR, D4, IS, 9G, LZ, YU, 9A, TI, OA,
FG, SM, OZ, Z2, LA, KL7, GD, GU, OX, TF, OY, ES, OE, LX, C3, V7,
HC8, SV, YO, JY, 4X, XE, TG, 5B, UY, SP, ER, Z3, HB0 and OD5.
Wow...I can't believe it myself, but they are all in the log and the
QSLs are already coming in. 6 Meters...the MAGIC BAND.''

Sunspot numbers for December 6 through 12 were 226, 200, 218, 225,
224, 154 and 183 with a mean of 204.3. 10.7 cm flux was 246.7,
225.9, 220.5, 224.2, 219, 220.6 and 236.7, with a mean of 227.7, and
estimated planetary A indices were 8, 5, 5, 3, 4, 4 and 12 with a
mean of 5.9.
NNNN
/EX