CW_QRP_PSK_RTTY_HomeBuilt of the Globe.

Low power amateur "ham" radio and building antennas,for CW, QRP,PSK, and RTTY, communications. By KB5DOH Allan


ARLP050 Propagation de K7RA

Posted by Allan kb5doh on December 14, 2012 at 9:10 PM


ARLP050 Propagation de K7RA



Propagation Forecast Bulletin 50 ARLP050

From Tad Cook, K7RA

Seattle, WA December 14, 2012

To all radio amateurs


ARLP050 Propagation de K7RA

Average daily sunspot numbers fell 13.5 points this week from 61.1

to 47.6. Average daily solar flux was about the same this week as

last, rising 1.1 points to 102.7. Geomagnetic indices were even

quieter this week than last.

Predicted solar flux is 115 on December 14, 120 on December 15-16,

115 on December 17-19, 110 on December 20-21, 115 on December 22-23,

110 on December 24-27, 100 on December 28-29, 95 on December 30

through January 3, 100 on January 4-5, and 105 on January 6-8. Solar

flux then jumps abruptly to 125 and 130 on January 13-14.

The predicted planetary A index is 5 on December 14-15, 8 on

December 16, 10 on December 17, 5 on December 18-28, 8 on December

29, 5 on December 30 through January 5, 7 on January 6-7, 5 on

January 8-9, 8 on January 10-11 and 5 on January 12-27.

OK1HH predicts the geomagnetic field will be quiet to unsettled on

January 14, mostly quiet December 15, quiet to unsettled December

16, active to disturbed December 17, mostly quiet December 18, quiet

December 19. A positive storm phase is expected December 20, with

active to disturbed conditions December 20-21, quiet to unsettled

December 22, mostly quiet December 23, quiet December 24, quiet to

unsettled December 25, mostly quiet December 26, quiet December 27,

quiet to active December 28, quiet December 29, quiet to unsettled

December 30-31, quiet January 1-4, active to disturbed January 5-6.

Both NASA and NOAA have tweaked their predictions for the peak of

the current solar cycle next year. To see the NOAA changes, go to and select PRF 1940 and go to page

12. Then open another browser window and select PRF 1944 and go to

page 16.

Notice that in the November prediction, the cycle peaks at 90 in May

through July 2013, and the smoothed sunspot number for January

through April is 81, 83, 85 and 88. In the December prediction, we

see two instead of three peak months, June and July 2013. The

numbers for January through May are 79, 81, 83, 86 and 88. This is a

marginally weaker predicted peak for cycle 24.

The latest NASA prediction is at

The change here is from 73 to 72 for a smoothed sunspot number

maximum in the December 10 prediction compared to the November 2

prediction. The other change is last month when they wrote "The

smoothed sunspot number (for 2012/02) is already nearly 67 due to

the strong peak in late 2011 so the official maximum will be at

least this high." This month the end of the line was changed to "at

least this high and this late."

Seen on Bob Kile's (W7RH) Facebook page on Tuesday: "For those low

band operators out there. The solar activity remains low and the

solar wind is under 300km/sec. That means West Coast to EU, boys! I

have six in the log last Saturday night and there have been West

Coast openings since last Friday."

I believe Bob is referring to 160 meters.

Lloyd Berg, N9LB of Oregon, Wisconsin (Oregon is a town just south

of Madison, Wisconsin) wrote about the 10 Meter contest:

"This year required a continuous effort on Friday evening, all day

Saturday and all day Sunday, including numerous 'dead band' times of

waiting and wondering if the band was going to come back or not. I

can see a large chunk of the band on my FLEX - Software Defined

Radio panoramic display - and when I say the band went dead, I see

it happening just like somebody turned down the RF gain - only took

a minute or two to extinguish all signals. I'd actually transmit

just to make sure the antenna was connected. I also looked out the

window many times to see if the antenna was still there (it was).

Really odd.

"At the beginning of the contest, the solar numbers looked awfully

low for decent 10m propagation: SFI=97, SSN=23, A=1, K=0. Conditions

were very weird from my Wisconsin QTH. The band kept going dead,

then we'd have a bit of garden variety E-skip 'here-and-there,' then

dead again. Then it would open up real wide, going way beyond simple

E-skip... North, South, East and West all at the same time.

"Worked everything East of the Mississippi in North America

(E-skip). Worked Hawaii, more Alaskans than in any other single

contest ever, many BC, and a NWT, but never heard most of the Rocky

Mountain states. Easy to work every active station in South and

Central America, and the Caribbean - day or night. Nice and strong

but short-lived openings to Azores, Cape Verde and Canary Islands.

"Worked several ZSs, VKs, ZLs and an E51 during a few short precious

minutes of openings on Saturday evening and again on Sunday

afternoon. No Japan or Asia heard at all. Only European contacts

were a couple of Spain and Portugal, again during a very brief

opening (well after their sunset)."

Thanks, Lloyd!

Jeff Hartley, N8II of West Virginia wrote, also about the 10 Meter

contest: "Sunday was noticeably better than Saturday in the 10M

contest this past weekend. I only worked about 15 EU stations all

weekend, but conditions to the west coast were extremely good and we

had plenty of Es Friday night and Saturday night into MN, WI, SD,

IA, MO, KS, and OK as well ME and VE1, VE9, VY2. The last hour

featured Es into KP4 and NC, SC, AL, KY, TN, FL, MS, AR, LA and TX.

"Highlights were working A45 around 1630Z Saturday and a great long

path Asian opening on Sunday which lasted for hours, starting around

1250Z on CW with about four JAs, BD7 at 1302Z, BV1 at 1308, XV1 at

1405, HS0 at 1414,and 9V1 at 1538, and also called on phone by HS0

at 1506. Sunday was extremely good to the west coast from 1710Z thru

2235Z, one WA station running a half watt was a solid S4 and mobiles

had solid signals. All states were worked on CW and only missed AK

on phone. There was propagation of some sort to all states at one

time or another with only the very close states on backscatter


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

email the author at, [email protected]

For more information concerning radio propagation, see the ARRL

Technical Information Service web page at For an explanation of the

numbers used in this bulletin, see An archive of past

propagation bulletins is at Find more good

information and tutorials on propagation at

Monthly propagation charts between four USA regions and twelve

overseas locations are at

Instructions for starting or ending email distribution of ARRL

bulletins are at

Sunspot numbers for December 6 through 12 were 49, 23, 35, 40, 49,

55, and 82, with a mean of 47.6. 10.7 cm flux was 97.4, 97.1, 101.1,

103.7, 104, 103.7, and 111.9, with a mean of 102.7. Estimated

planetary A indices were 1, 1, 1, 4, 3, 2, and 2, with a mean of 2.

Estimated mid-latitude A indices were 2, 1, 1, 3, 3, 2 and 3, with a

mean of 2.1.



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