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 Previous: Surfin': Finding More DX and VNAs |  Next: Field Day 2008 Rules and Forms Now Available |
After a solid week of sunspots -- January 29 to February 4 -- the following three days have been blank. February 2 was an active geomagnetic day with a solar wind stream spewing from a coronal hole near sunspot 982. Another solar wind stream from a coronal hole is expected to strike Earth on Sunday, February 10 causing unsettled conditions.
The predicted planetary A index for February 8-15 is 8, 12, 15, 10, 10, 10, 10 and 5. That was from NOAA and the US Air Force; Geophysical Institute Prague predicts unsettled conditions February 8, unsettled to active February 9-10 and unsettled again on February 11-14. The Australian Space Forecast Centre's geomagnetic forecast expects mostly unsettled to active conditions with storm periods possible at high latitudes on February 9, and mostly unsettled with isolated active periods and storm levels at high latitudes on February 10.
Following this weekend, NOAA predicts the next active conditions around February 28-29. Their prediction for solar flux is flat at 70 for each of the next 45 days; this probably indicates little or no sunspot activity. Sunspot numbers for January 31-February 6 were 15, 19, 16, 14, 14, 0 and 0 with a mean of 11.1. The 10.7 cm flux was 72, 71.1, 71.8, 71, 71.3, 70.5 and 71.6 with a mean of 71.3. Estimated planetary A indices were 5, 18, 19, 12, 6, 3 and 4 with a mean of 9.6. Estimated mid-latitude A indices were 3, 10, 19, 10, 6, 2 and 2 with a mean of 7.4.
Bob Leo, W7LR, of Bozeman, Montana and IS0/YO3RA (Sardinia) have been trying for several years to make contact on 160 meters. Bob claims 228 countries on 160, but says Sardinia seems to be "a black hole," even though both have what he calls "reasonable stations" for that band. With some acreage for antennas, Bob runs full power, has various receiving antennas pointed toward different directions and even a 2-element transmit array toward Europe with 4.5 db gain.
He asked what time would be best to work Sardinia on 160, and frankly I didn't know, except to say that I would expect darkness at both ends of the path when successfully making contact. The propagation modeling programs generally don't work below 3 MHz. I noted that this weekend darkness should extend over both locations from 0036-0629 UTC, or at least the sunset in Bozeman will be 0036 UTC and sunrise in Sardinia is at 0629 UTC. Bob e-mailed back and said he finally heard YO3RA at 0510 UTC. He hopes to work him this season before YO3RA departs Sardinia on February 15.
Several readers wrote to ask about the recent sunspot mentioned in last week's bulletin, hoping it was a Solar Cycle 24 spot. Alas, sunspot 982 had Cycle 23 polarity. Any Cycle 24 spots in the near future will be reported here.
Stan Tacker, N5OHM, of Tulsa, Oklahoma, writes that the absence of sunspots and geomagnetic activity is great for 160 meters, but that it creates problems for AM broadcast stations. He operates one in Northeast Oklahoma on 1.57 MHz (191 meters), a portion of the AM broadcast band where stations run low power, sometimes 250 W during the day, and as little as 6-8 W at night. There is also a Mexican "border blaster" station on this frequency and his station is experiencing QRM well into mid to late morning, only hours after sunrise. Stan's station is running 1 KW and broadcasts in the daytime only.
Check Zabriskie, KE5HPY, in Houston, Texas, wrote on February 2 that the 60 meter shortwave broadcast band (4.4-5.1 MHz) was jumping on January 29-31 from 0300-0500 UTC. He heard African stations "that rarely rise above the noise at this location." He copied Angola, Madagascar, Chad, South Africa, Swaziland and Botswana, all as loud as Midwest AM broadcast stations.
Regarding the 60 meter ham band, check out a Web page devoted to that band.
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.
| Previous: Surfin': Finding More DX and VNAs | Next: Field Day 2008 Rules and Forms Now Available |
