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ARRL Propagation Bulletin ARLP051 (2016)

ARLP051 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 51  ARLP051
From Tad Cook, K7RA
Seattle, WA  December 16, 2016
To all radio amateurs 

ARLP051 Propagation de K7RA

Average daily solar indices over the past week were lower than the
previous seven days, with average daily sunspot number declining
from 40.9 to 13, and average daily solar flux dropping 10 points
from 82.2 to 72.2.

Geomagnetic indicators were higher, with average daily planetary A
index rising from 4.9 to 13.3, and mid-latitude A index from 3.4 to

Predicted solar flux is 72 on December 16-20, 75 on December 21-22,
88 on December 23-27, 86 on December 28-29, 88 on December 30
through January 1, 86 on January 2-3, 84 and 82 on January 4-5, 80
on January 6-7, 73 on January 8-9, 75 on January 10-14, 82 on
January 15-16, 86 on January 17-18, 88 on January 19-23, 86 on
January 24-25 and 88 on January 26-28.

Predicted planetary A index is 5 on December 16, 8 on December
17-18, 15 on December 19-20, then 25, 28, 12, 10 and 8 on December
21-25, 5 on December 26 through January 1, then 8, 10, 20 and 22 on
January 2-5, 16 on January 6-7, 8 on January 8, 5 on January 9-12, 8
on January 13-14, then 12, 16, 22 and 30 on January 15-18 then 12,
10 and 8 on January 19-21, and 5 on January 22-28.

From Petr Kolman, OK1MGW, "the geomagnetic activity forecast for the
period December 16 to January 11, 2017:

"Geomagnetic field will be:
Quiet on December 16, 30-31, January 10-11
Mostly quiet on December 17, 26-29, January 8-9
Quiet to unsettled on December 18-19, 23-25, January 1-3
Quiet to active on December 20, January 6-7
Active to disturbed on December 21-22, January 4-5

"Amplifications of the solar wind from coronal holes are expected on
December 17-23, January 2-7."

Evan Rolek, K9SQG of Beavercreek, Ohio wrote: "For me, poor
propagation is something that is LOVED! Why? It is easier to make
A-B antenna comparisons and to identify which antenna works the
best, then I'll be ready when propagation improves. (Not for me
since it will be 5-10 years when it gets better, and I've already
submitted my application to the Silent Key Club.)"

In conversation with Lee Gordy, W4KUT, I asked him about 10 and 15
meters at the peak of Cycle 19.

"Just after the peak of SS Cycle 19, my only antenna was a 40 meter
dipole (up abt 30 or 40 feet), fed with 75 ohm xmt VFO was
pretty much stuck on the low end of 40 CW.

"I had a Viking Ranger II, which had a Pi Network output. It could
load up bed springs. So, I could trick the 40 mtr ant into radiating
just about ANY frequency, but with way less than the advertised
output power.

"One summer afternoon there was a knock on the door. It was my ham
buddy, K4AIP (Roger, aka Rozy), out of breath, he'd just bicycled
over from across town...(Not everybody in those days had
telephones).  'Hey man, I just worked Nigeria on 15! Fire up your
rig. I bet he's still there.'

"We went into the shack and tuned up my 40 mtr ant on 15 AM phone
(this was before the proliferation of SSB). And yep, there was the
Nigerian at 20 over S9...WOW!

"Because of the mismatch, I probably had less than 5 watts ERP. I
gave the guy a call...HE CAME BACK to me!  WOW!

"From Atlanta to Nigeria and back, on less than 5 watts. I've still
got that QSL card - 5N2FEL.

"Cycle'll probably never be that good again - Lee, W4KUT"

Regarding propagation during last weekend's ARRL 10 Meter Contest,
Jon Jones, N0JK of Lawrence, Kansas wrote:

"Sporadic-E popped up on both 6 and 10 meters Saturday Dec. 10. The
Es allowed contestants in the ARRL 10 meter contest to fill their

"10 was wide open to W4, W5 and west to AZ, CO and NM from Kansas
1645z to 1800z. My first contact was VP5CW at 1645z via double hop
Es. Worked several stations in Colorado which is a fairly short

"I went out fixed mobile later and found strong Es on 10 meters from
1930-2200z to W1, W2 and W3. MUF at this time seem lower, probably
just above 30 MHz Worked VHFers W3EP and K1RO. Only F-layer DX I
worked was PX2B at 2052z."

Sam, K5SW EM25 Oklahoma wrote me about 6 meter Es Dec. 10:

"The minor E season of Dec/Jan had 50 MHz open today, Dec. 10th.
From 1700z-1800z I worked FM05, FM17, and FM16 stations. I heard
beacons from that area. Maybe we will have some E-skip during the
Jan VHF contest, too."

Jon wrote this on Sunday:

"The 10M Contest was a bust Sunday.  Only Q I had was with W2GDJ NY
at 1904z.

"Ran 5 W to mobile whip both days."

Also got this report from Bil Paul: "Of course the 10m contest was
happening this weekend. I wasn't at all sure 10m would be open. But
I went up to check it out.

"DX-wise, I found South America coming in: Peru, Chile, and
Argentina. I was able to contact CE2DK in Chile and a Mexican
station with 10w SSB and a vertical dipole.

"I heard an American East Coast station coming in with a peculiar
flutter for a short time.

"Bil Paul KD6JUI Dixon, CA"

Gary, K7GS of Spokane, Washington wrote regarding the 10 meter

"Conditions in the inland Pacific Northwest were poor at best. Good
TEP openings to SA on Saturday along with some east coast and
southeast propagation. On Sunday no east coast or Midwest
propagation but we did experience some TEP to central SA plus one or
two W6s via short skip. Let's hope it will not be much worse in the
coming few years."

A couple of interesting links from Brian Calvert, KG7MU, regarding
out of phase solar magnetic fields:

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 web page at, For an explanation of
numbers used in this bulletin, see An archive of past
propagation bulletins is at More good
information and tutorials on propagation are 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 8 through 14 were 14, 12, 0, 13, 13,
14, and 25, with a mean of 13. 10.7 cm flux was 74.8, 72.9, 72.2,
71.4, 70.8, 71.2, and 72.4, with a mean of 72.2. Estimated planetary
A indices were 23, 25, 16, 15, 6, 4, and 4, with a mean of 13.3.
Estimated mid-latitude A indices were 14, 18, 11, 11, 5, 2, and 2,
with a mean of 9.


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