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The K7RA Solar Update

11/20/2009

Sunspot 1029 made its trip around the Sun and has re-emerged as sunspot 1032. A new sunspot 1033 has come over the Sun's eastern limb. This steady appearance of sunspots has raised the MUF over many paths, and 15 meters is beginning to open regularly.

Sunspot activity also seems to be increasing steadily of late. Daily sunspot numbers for November 5-19 were 15, 16, 11, 0, 14, 13, 11, 11, 0, 0, 11, 12, 0, 29 and 30. Sunspot numbers for November 12-18 were 11, 0, 0, 11, 12, 0 and 29 with a mean of 9. The 10.7 cm flux was 73.2, 74.1, 74.8, 75.1, 76.2, 77.2 and 76.1 with a mean of 75.2. The estimated planetary A indices were 1, 2, 5, 4, 1, 1 and 2 with a mean of 2.3. The estimated mid-latitude A indices were 0, 2, 3, 3, 0, 0 and 2 with a mean of 1.4. The predicted solar flux for the near term is 78 for November 20-21, 80 for November 22-26 and 70 on into early December.

In the Southern Hemisphere -- which gets more solar radiation this time of year -- you can see a pronounced effect on the f0F2 reading in the afternoon (local time is UTC +6.5 hours). This is a measurement taken with an ionospheric sounder on Cocos-Keeling Islands in the Indian Ocean, 12.5 degrees South latitude and 96.8 degrees East longitude. The instrument sweeps a radio signal across the HF spectrum, beamed straight up to the ionosphere overhead, and it measures the strength of the signal bouncing back to determine optimum frequency. You can see during mid-day f0F2 is going above 10 MHz.

Of course, your results may vary. The effect was pronounced from 0600-1400 UTC on November 19, and not quite as enhanced on November 20, 0700-1000 UTC. Unfortunately, these ionosonde records don't go back but a day or two. You will see less effect this time of year in the Northern Hemisphere, as seen at a record of ionosonde data in Italy here. If you go here, you will see similar data taken in the UK.

You can check a list of links for 68 different locations, but some of them seem inactive. For instance, after months of checking, I have never seen a bit of ionosonde data from Eglin Air Force Base in Florida, in the file Eglin_iono.txt. Another interesting tool to see varying MUF around the world, updated every five minutes, is here. The contour lines show the MUF over that particular area. During the day recently, some areas over Africa were going above 30 MHz.

This weekend is the ARRL SSB Sweepstakes Contest and conditions are expected to be good for this popular domestic operating event. There is a possibility of some disturbance from unsettled geomagnetic conditions, possibly peaking on Saturday. Predicted planetary A index for November 20-24 is 10, 15, 10, 6 and 5. Possible mild disturbance on Saturday would be from a wind stream from a coronal hole that currently faces Earth. The following weekend (November 28-29) is the CQ Worldwide CW DX Contest, followed by the ARRL 160 Meter Contest December 4-6, then the ARRL 10 Meter Contest December 12-13. This weekend we should see some propagation on 15 meters over the domestic paths for the contest. For instance, Dallas to Seattle should be good on 15 meters 1630-2130 UTC, 10 meters possibly 1800-2000 UTC. California to Ohio on 15 meters should work 1600-2130 UTC, and possibly 1630-2030 UTC. Dallas to Boston looks good for 15 meters 1600-1930 UTCz, and Dallas to Vancouver looks good on 15 meters 1630-2130 UTC. Atlanta to Edmonton, Alberta also looks good for 15 meters 1630-2030 UTC, with 10 meter possible 1730-1900 UTC.

Evan Rolek, K9SQG, of Beavercreek, Ohio, has been noting stateside and short skip 40 meter conditions this year. Back on April 20, he wrote: "Over the past month, 40 meters has been dismal for daytime net activities. In addition to storm-related static, signals range from 'normal' to 20-30 dB below normal. Interestingly, I'm experiencing one-way skip with certain stations, but not all. For example, a station that I share net control with on the Georgia 40 Meter Traders' Net on Sunday morning is down something like 15-20 dB on my S-meter. Still solid copy, but he is unable to copy me at all."

But recently Evan notes an improvement. On November 16, he wrote observations "based upon some 40 meter swap and technical net participation. Recent weeks have shown an improvement in signal strength and areas of coverage in the 1400-1500 UTC and 2000-2100 UTC time frames (morning and afternoon on North America's East Coast). Signals are up 10-30 dB (yes, 10 to 30 decibels) and the areas of coverage have improved. Close-in regions under 200 miles that were almost uncopyable for the past several months now have signals that are 10-35 dB over S9. Talking with stations in Minnesota, Louisiana, New Hampshire, Florida and Mississippi are becoming more frequent. I hope this is the sign of improvements for a long term basis."

Check out this Web site for an interesting article about a solar tsunami, and how STEREO gives a 3-dimensional view to better judge the height of solar disturbances.

Larry Godek, W0OGH, of Gilbert, Arizona, says conditions are improving: "First of all, I run only 100 W here and all antennas except for the 20 meter beam at 30 feet are dipoles. DX has been quite good of recent. For me to work anything on 20 meter SSB is something that hasn't happened for years and years around here; however, I've worked ZB2EO, 6W/EI6DX, T30KI, ZS6JPY (40 meter SSB) and TL0A which is not impressive to some, but it sure gets my attention. Surprisingly, the African contacts have been in the morning hours, who I normally can't work, much less hear, until after 2100 UTC -- just too much RF blocking going on to the east of me. This morning on the ZB2 station, I had called him a few minutes earlier, but again the East Coast was doing all the talking. Shortly thereafter, I heard him calling CQ DX with no answers. While signals were only about 5-5 both ways, it was a clear path with no other stations heard on the frequency. Quite a surprise. Last night, November 13 (0346 UTC) ZS6JPY was heard calling CQ on 40 SSB. No one appeared to be returning his calls so I gave him a shout. Again using 100 W and a weird 40 meter dipole antenna configuration, I was able to work him. Kind of reminds me of the days back in the late 50s when you could load up the bedspring and work the world. Wow! Things are improving! Lots of DX on the 30 meter band from Europe, as well as the Caribbean region and Pacific. The CW bands have been much better. I've even been able to work DX on 17 meters with the 20 meter beam, greatly reduced power of course, but never the less, propagation was good enough for it to happen."

Vic Woodling, WB4SLM, of Centerville, Georgia (EM82dp), experienced some interesting tropospheric propagation earlier this week. Vic wrote, "Tropo last night (14-15 November) early this morning across the southeast to the southwest. Couple examples: I worked our old friend Pat, WA5IYX (San Antonio, Texas EL09ql), on 2 meter CW, 909 miles. I also made a 'sweep' from 6 meters, 2 meters, 222, 432, 902, 1296, and 2304 MHz with Bill, W3XO/5 (Kerrville, Texas EM00kd), 925 miles. I 'think,' but really can't remember, if this was my personal best on 6 meter tropo, but should be. I know it was (my best) on 2304 and& 902 MHz. In chatting with Bill, W3XO, and Drew, KO4MA (New Port Richey, Florida EL88pg), early this morning, they said they had a 997 mile contact on 222 MHz."

James French, W8ISS, sent in a comment in response to the info about backscatter in last week's bulletin: "We had this exact thing happen on 10 meters just before the November Sweepstakes started November 7. I gave a call out asking if the frequency was in use, then started calling CQ. With the newly installed tri-band beam pointed west, a local station about 10 miles away answered back. He said we were weak so we swung the beam east (his direction) and lost him totally. Swung the beam back west again and there he was. We were in Ann Arbor, Michigan and the other gent was in Belleville, Michigan. I was wondering if we had installed the beam backwards as we had just gotten it up on the 65 foot tower about two weeks ago and was getting ready for Sweepstakes that weekend. Jay, WB8TKL, told me about how it was probably backscatter. I wouldn't have thought it possible that close, but there it had happened in front of me."

Finally, Chris Kelly, K0PF, tells a story about operating mobile recently, and experiencing some of that old shortwave magic: "My note regards an interesting contact I had the other night. I was driving to Colorado State University about 9 PM to pick up my son who had a late exam. I decided to switch on the rig in the pickup and see if there was anything happening in this lowest of sunspot days. I heard and worked a station on Vancouver Island, who was very kind and turned his 20 meter beam my way because he heard a mobile. He was working a lot of JAs who were barely audible to me. I tuned around a bit and heard an interesting accent and called, receiving a 5/7 report from ZL1BOS! I thought this was quite a feat from a 100 W mobile (he must have a good antenna and receiver). A few minutes later and all the JAs had faded out and 20 seemed dead. I dropped to 40 meters, and promptly heard a ZS1, about 5/5. By the way, the antenna on the truck was a whip using a 20 meter resonator, tuned with a SGC antenna coupler -- not even the right resonator for 40! I have been a ham for almost 3 sunspot cycles, and while I am not very active right now (obviously busy raising a family), I am still amazed at the propagation that opens up even at the bottom of the cycle. Hearing the opposite side of the Earth via two paths on the same night from a mobile station. Wow!"

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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