Friday, June 05, 2009

Amateur radio propagation report

Propagation Forecast Bulletin 23 ARLP023
From Tad Cook, K7RA
Seattle, WA June 5, 2009
To all radio amateurs

ARLP023 Propagation de K7RA

It is so great to see some real Cycle 24 sunspot activity this week. Instead of a phantom that pops into view one day and is gone the next, we have sunspot 1019, which has persisted for five days, so far. Emerging on Sunday, May 31, the resulting daily sunspot numbers through June 4 are 15, 23, 19, 17 and 17. This is a Cycle 24 spot, and at high latitude too, which is an indication of a new cycle spot.

Meanwhile, the low solar wind and quiet geomagnetic conditions continue. Currently spot 1019 is about to fade, although it is still a few days away from crossing the eastern limb to the far side. NOAA and the US Air Force expect geomagnetic conditions to continue to be quiet, and a planetary A index around five is predicted until June 29. Predicted solar flux values are 72 for June 5-6, then 74 on June 7-13.

Geophysical Institute Prague predicts quiet geomagnetic conditions June 5-8, quiet to unsettled June 9-10, and quiet again June 11. Time now to look at our 3-month average daily sunspot numbers to spot trends. It looks like the numbers are up, slightly.

The three-month average of daily sunspot numbers for January through April was 2.4, 2.3, 1.5 and 2. The last number, centered on April, is the sum of all daily sunspot numbers for March through May, divided by the number of days.

Since 2007, the 3 month moving average has been:

Jan 07 22.7
Feb 07 18.5
Mar 07 11.2
Apr 07 12.2
May 07 15.8
Jun 07 18.7
Jul 07 15.4
Aug 07 10.2
Sep 07 5.4
Oct 07 3.0
Nov 07 6.9
Dec 07 8.1
Jan 08 8.5
Feb 08 8.4
Mar 08 8.4
Apr 08 8.9
May 08 5.0
Jun 08 3.7
Jul 08 2.0
Aug 08 1.1
Sep 08 2.5
Oct 08 4.5
Nov 08 4.4
Dec 08 3.7
Jan 09 2.3
Feb 09 2.1
Mar 09 1.5
Apr 09 2.0

The average daily sunspot number for just the month of May was 4, which indicates a nice trend following the March and April 3-month averages.

David Witkowski, W6DTW of San Jose, California was happy to see the reports of night time 20 meter propagation from N6CAS, and notes that on May 20 he worked LY1000A (Lithuania) at 0405z, ES1QD in Estonia at 0612z on May 22, and OH5LF (Finland) at 0635z on May 23. He worked them all using 100 watts and a vertical antenna. He wrote, "I told some friends here in San Jose that I'd worked Europe barefoot at 11:00pm local time and a few of them gave me the 'Oh yeah, sure you did' look. Thanks for vindicating me."

David continued, "Regarding the question of "dead" versus "unoccupied" bands; I wrote a blog article recently on this topic. (See .) During Summer Es I used to listen to 28.4 and/or tune from 28.3-28.5 to check for openings. Recently I made the discovery that listening on CB channel 38-LSB (27.385) is a much better way to do a quick check for openings; I have monitored stations from all over the western US burning up "38 lower" well into late evening, while 10 meters sits idle. Many times there is propagation; we're just not using it."

Howard Estes, WB4GUD of Franklin, North Carolina also likes to check Citizens Band activity for a 10-meter propagation indicator. He wrote, "I agree with W1ZI, the bands aren't dead, we're just lazy. How often do you scan a band, don't hear anything, and go somewhere else? I've started checking the CB channels for activity. If I can hear the Big Frog Gigger in LA (that's lower Alabama), probably 10M is open to somewhere."

Mark Lunday, WD4ELG of Hillsborough, North Carolina wrote about a June 1 E-skip opening on 6 meters that still continued at 0400z on June 2. "I worked 12 stations on CW and SSB across the Midwest on 6. Also, had some multi-hop on 10 meters using WSJT JT65A and heard Oregon. Second night in a row that I was hearing Es late at night on 10 meters using WSJT weak-signal propagation."

Mark said he likes to use DX Sherlock, at .

Bill Turner, W4WNT of Matthews, North Carolina has good luck lately with PSK on 20 meters, even when there are no sunspots. He is running 25 watts into a G5RV at 25 feet, and on May 21 at 0345z he worked Peter, ZL1PWD who reported working 12 stations that day.

Erik Jacobsen, KB9BNY of McHenry, Illinois sent a message titled, "20-meter PSK31 has been on fire this week." He wrote, "Tuesday, with the sunspot number at 19 and the solar flux at 72, 20 meters nicely opened up for world wide communication. I participate in the PSK reporter network ( ). Basically, when a reporting station receives the de callsign callsign pattern, the location of the transmitting station is then plotted on a map. When I checked the map on Tuesday morning, I saw a Pakistani station, two New Zealand stations and a Japanese station plotted. It just goes to show you how well 20 meters can perform with a small amount of power (usually under 30 watts), a narrow-band signal, and relatively modest solar conditions."

He continues, "I preserved the map for historical purposes at . Tuesday's total monitoring take for a 24 hour period was 30 countries. I occasionally blog my PSK reporter observations at . My current PSK reporter map can be viewed at ."

Thanks, Erik! Great stuff.

Again this week we have a book recommendation. Bill Scholz, KB1SGY of Greenwich, Connecticut advises checking out "The Sun Kings; The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began."

Bill writes that this is "an engaging book by Stuart Clark that describes, in great detail, how the great astronomers of the 19th century linked sun spots, solar flares, auroras and magnetic storms. An excerpt from the flyleaf: 'In September of 1859, a cloud of seething gas engulfed the Earth and a blood-red aurora erupted across the planet. Around the world, telegraph machines burst into flames, while compasses reeled as if struck by a massive magnetic fist. No one knew what could have released such strange forces upon the Earth - no one, that is, except the amateur English astronomer Richard Carrington.'"

He continues, "It's a great read and I recommend it highly if you're interested in the connection between these phenomena."

Last week's bulletin mentioned a consumer communications product out of Japan that would require text messengers to learn Morse code. We asked if anyone could decode the Japanese in a graphic on a web page talking about the product, and Brett Graham, VS6BG says it is just a banner ad for a television show. He thought the product might be for real, but checked with JA3USA, who thought it was an April 1 joke. But Brett says, "The idea does have something going for it."

In last week's bulletin we presented some confusing text regarding scientific notation and numbers representing the area covered by sunspots, at least it confused me. I was worried about it, so I checked with K9LA, who got me on the right track. But K1SFA at ARRL HQ was concerned when she got it from me, so she passed it on to a ham who is an astronomer for a fact check. Somehow it got changed back to the way I had it in the first place, before getting input from K9LA. So at this point I can't correct it, although I believe K9LA had it right. More later.

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 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 .

Instructions for starting or ending email distribution of this bulletin are at .

Sunspot numbers for May 28 through June 3 were 0, 0, 0, 15, 23, 19, and 17 with a mean of 10.6. 10.7 cm flux was 67.7, 68.2, 68.5, 68.5, 72.5, 71.9, and 72.5 with a mean of 70. Estimated planetary A indices were 7, 5, 3, 3, 3, 2 and 4 with a mean of 3.9. Estimated mid-latitude A indices were 5, 4, 2, 3, 2, 2 and 4 with a mean of 3.1.
(Dave Raycroft/ODXA)