Propagation de K7RA

This week (January 18-24) saw lower sunspot numbers (seven points lower, on average) than the previous week. Geomagnetic numbers were also lower, especially the past few days. January 22 through the first hours of today (January 26) at all latitudes had K index readings of 0 or 1.

Low geomagnetic activity will be good for this weekend's CQ World Wide 160-Meter CW Contest. But there is currently a flare-spewing sunspot just around the Sun's eastern limb, and when it swings into view we'll see solar flux about 10 points higher than now, and briefly some higher geomagnetic numbers. The planetary A index for January 26-31 is predicted at 5, 5, 15, 20, 20 and 15.

Geophysical Institute Prague predicts quiet conditions for January 26-27, unsettled January 28, unsettled to active January 29-30, unsettled January 31, and quiet to unsettled February 1.

Bob McQuarrie, ZL3TY writes that while we have perhaps had a not-so-great winter season for VHF E-skip in the Northern
Hemisphere, down in the Southern Hemisphere they are having a wonderful spring and summer E-season, and comments "the best experienced in many years." His reports are from over a month ago, but last week he said "the good conditions continue."

Bob writes, "The 6m Sporadic E openings this summer have been the best I have experienced in the past 18 years of operating on the band. All mainland VK call areas have been worked and there have been many prolonged openings into VK6 and VK8. The band has been open to some part of VK every day since mid December."

He continues, "On the morning of 17 November, while operating meteor scatter tests to VK, 2m opened to VK2 briefly and 3 Sydney stations were worked."

Bob goes on to say, "The next 2m tropo opening started here at 1105am on Sunday 10 December with a QSO with VK2GKA, then the band remained open until late Monday night. On Sunday I had SSB/CW QSOs with 11 VK2s and 5 VK3s, also digital (JT65b) QSOs with 6 VK3s, on Monday the opening continued with SSB/CW QSOs with 15 VK2s, and 3
VK4s and a digital QSO with VK4WS. On Sunday I had several 70cm QSOs with VK2FZ."

He ends with, "On Saturday 23 December there was an excellent Sporadic E opening starting at 911am NZT which lasted until 1145am. Stations worked included 11 VK2s, 3 VK1s and 3 VK7s. Conditions were so good an easy QSO was had with VK7HSE who was running 50W to a 1/4 wave GP antenna."

Thanks, Bob.

Thanks also to N0AX's ARRL Contest Rate Sheet and N2IC for this tip. Go to the Meteorology and Training web site at,
http://meted.ucar.edu/topics_spacewx.php for some wonderful online training on space weather. You will need the Adobe Flash Player from http://tinyurl.com/zgkz2 if you don't already have it. These courses are wonderfully illustrated and animated, and free.

If you would like to make a comment or have a tip for our readers, email the author at, k7ra@arrl.net.

For more information concerning radio propagation, see the ARRL Technical Information Service at,
http://www.arrl.org/tis/info/propagation.html.

For a detailed explanation of the numbers used in this bulletin, see http://www.arrl.org/tis/info/k9la-prop.html.

An archive of past propagation bulletins is at, http://www.arrl.org/w1aw/prop/.

Monthly propagation charts between four USA regions and twelve overseas locations are at, http://www.arrl.org/qst/propcharts/.

Sunspot numbers for January 18 through 24 were 23, 15, 31, 18, 23, 18 and 15 with a mean of 20.4. 10.7 cm flux was 76.8, 76.3, 78.8, 78.6, 78.5, 79.3, and 80.4, with a mean of 78.4. Estimated planetary A indices were 16, 11, 7, 7, 3, 2 and 1 with a mean of 6.7. Estimated mid-latitude A indices were 9, 9, 6, 7, 2, 3 and 1, with a mean of 5.3.

Source: The American Radio Relay League

• All propagation reports can be found at:
http://www.southgatearc.org/propagation