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The K7RA Solar Update

04/17/2009

Still no sunspots, and again we saw a prediction for slightly higher solar flux slip away. If you go here and click on any forecast prior to April 14, you will see solar flux numbers at 72 predicted for the end of this month. But in the few days since then, any predicted values over 70 have vanished -- including another set of slightly higher numbers in late May. Sunspot numbers for April 9-15 were 0, 0, 0, 0, 0, 0 and 0 with a mean of 0. The 10.7 cm flux was 70.1, 69.4, 69.3, 69.3, 68.4, 69.4 and 69.4 with a mean of 69.3. The estimated planetary A indices were 12, 8, 9, 8, 4, 2 and 3 with a mean of 6.6. The estimated mid-latitude A indices were 9, 6, 7, 4, 3, 1 and 2 with a mean of 4.6.

Hank Pfizenmayer, K7HP, of Phoenix, Arizona, has been using beacons to let him know when bands are open. He is discovering what others have reported -- when a band is quiet, this doesn't mean the openings are not there. Hank wrote, "While the VK9GMW folks have been on, I have been checking the beacons on 17 and 15 meters and on 15 specifically, well over half the days between 2000-0300 UTC, I hear the ZL6B beacon -- usually I hear the KH6, sometimes the W6. This is with a KT34 at 42 feet in a noisy suburban location. It is interesting to note that I have not heard the VK beacon at all -- about 1900 miles farther, but essentially same beam heading Of course, the LU and OA beacons are there almost every day even with the antenna on VK/ZL. Several days I can copy the ZL6B beacon at the 100 mW step."

Jeff Hartley, N8II, of Shepherdstown, West Virginia, had some thoughts to share with Mickey, K5ML, who had comments featured in last week's bulletin:

"I saw your comments in the ARRL prop bulletin and felt compelled to say few things about conditions now vs the top of the cycle. In some parts of the world, some days are much better than others. This was the case this week on April 7 when Spain was worked on 17 meters at 2130 UTC and 30 meters was wide open to EU and AF working 3B8MM, and the Western Pacific at the same time, allowing me to catch Mellish Reef for a new one on 30 meters. Southeast Asia (even JAs are not easy from here near DC) are extremely difficult to work here at the bottom of the cycle, especially mid-winter, because there is essentially no useable ionosphere around the North Pole. Also, many ops are poorly equipped for 10 MHz and below with very limited antennas, but have a tribander for 10-20 meters."

He continued: "With your vertical and a good 10 meter opening, you will be amazed how strong long haul DX signals are and how easy they are to work. I was fairly new to DXing in the fall of 1978 and had just put up a 4-el Yagi for 10 meters at 45 ft and it was a real killer into everywhere from Central Asia, to Europe, Africa and South America. RH8EAA in Turkmenistan was S9+ in October 1978 day after day, and I was able to call CQ and get many answers from UA9 and UL7 (now UN). During one CQWW CW contest, G4BUO called me running less than one milliwatt and I was able to copy him on the second try! So, long story shortened, it is a lot more fun with higher solar activity. Six meters will be full of activity at the cycle peak, and I can't wait for the next one. In the meantime, I'm having fun chasing countries on 160 and 30 meters primarily, and hunting counties as well".

Be sure to check out NASA's recent release of new information about coronal mass ejections as observed by the STEREO mission.

Amateur solar observer Tad Cook, K7RA, of Seattle, Washington, provides this weekly report on solar conditions and propagation. This report also is available via W1AW every Friday, and an abbreviated version appears in The ARRL Letter. Check here for a detailed explanation of the numbers used in this bulletin. An archive of past propagation bulletins can be found here. You can find monthly propagation charts between four USA regions and 12 overseas locations here. Readers may contact the author via e-mail.



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