In the latest issue of the K7RA Propagation newsletter, Tad Cook writes that you can get the latest WWV geo-alert via the Internet and by telephone:

The alerts are transmitted at 18 minutes
after each hour, and you can also read the latest copy at
http://sec.noaa.gov/ftpdir/latest/wwv.txt. If you want it via
telephone, call 303-497-3235. The broadcasts are updated every three
hours, after 0000z, 0300z, 0600z, 0900z and so on.

This could be very handy next time the bands seem dead and you don’t want to run outside to see if your antenna is still up in the air or not. :)

I mentioned in a previous post about the horrible conditions on Sunday. On Monday, I got the following special propagation bulletin from the ARRL:

QST de W1AW
Propagation Forecast Bulletin 20 ARLP020
From Tad Cook, K7RA
Seattle, WA May 16, 2005
To all radio amateurs

This is a special edition of the Propagation Forecast Bulletin.

On Friday the Thirteenth (May 13, 2005) at 1650z a tremendous
explosion near sunspot 759 blasted toward earth. The impact on the
earth’s magnetic field was felt at 0230z on May 15, producing an
extreme geomagnetic storm.

I use a service from http://www.spaceweather.com called
“SpaceWeather PHONE.” I can set parameters for alerts, and the
service calls my cell phone when events occur, such as the planetary
K index rising above a set value. The service rang me up so many
times this weekend that I finally shut the phone off. I could have
gone to the web and shut it off or raised the parameters, but at the
time I just wanted to roll over and go back to sleep.

On Sunday, May 15 the planetary K index reached 9. This is huge.
The middle latitude, high latitude and planetary A indexes for
Sunday were 44, 77 and 105 respectively, all very high values. The
planetary A index predicted for Monday, May 16 is 40. Solar flux is
expected to stay around 100 for Monday through Wednesday, May 16-18.

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

For more information concerning radio propagation and an explanation
of the numbers used in this bulletin see the ARRL Technical
Information Service propagation page at,
http://www.arrl.org/tis/info/propagation.html. An archive of past
bulletins is found at, http://www.arrl.org/w1aw/prop/.

I guess Friday the 13th was an unlucky day for radio amateurs.

When guys in our club start to talk about A-indexes and K-indexes, I normally say that I don’t use either of those to predict propagation. When they’d ask what I do use, I reply, “I use the E-index.”

“What’s the E-index?” they ask.

“Well,” I joke, “E stands for ‘ear’ and if I can hear stations on a band then I figure that propagation is pretty good. If I don’t hear any stations, then it’s probably bad.” That usually get a chuckle out of them.

I may be changing my tune, however. This week, I covered propagation in the General Class license course. To cover it properly, I had to bone up on the topic myself. In the course of doing so, I found the topic to be much more interesting and useful than I would have thought, and there are quite a few resources on the Web that makes it easy to learn.

Here are a few websites to explore:

• Collection of Propagation Information. As the name implies, this site collects data related to propagation and displays it on a single page. Included are various measurements of the solar flux index, A- and K-indexes, sunspot numbers and a grey line map.
• Near-Real-Time MUF Map. This map, updated approximately every five minutes, shows Maximum Usable Frequencies (MUFs) for 3,000 kilometer radio signal paths. It also shows auroral ovals and the sunrise/sunset terminator (gray line). The map is produced by PropLab, a program you can purchase on this website for $150.
• KN4LF’s Radio Propagation Theory Notes. KN4LF is a space weather scientist with the U.S. government.
• International Beacon Project. The NCDXF, in cooperation with the IARU, constructed and operates a worldwide network of high-frequency radio beacons on 14.100, 18.110, 21.150, 24.930, and 28.200 MHz. These beacons help both amateur and commercial high-frequency radio users assess the current condition of the ionosphere.
• DX Atlas. this company produces the software DXatlas, Ionoprobe, and HamCap to help hams predict propagation conditions. While not free, you can download the programs and use them for free for 30 days.

I really don’t need yet another thing to learn and work at, but knowing about this stuff will certainly make you a better amateur radio operator. I think it will be worth the effort.

Update 5/27/05: In the May 4, 2005 edition of the Contest Rate Sheet, Ward N0AX writes:

The details of short wave propagation are available in a detailed tutorial Introduction to HF Radio Propagation available at no charge from the Australian Space Weather Agency at http://www.ips.gov.au.

I just looked it over quickly, but the sections I read were very well written. I’ll not only be recommending this to my General Class students, but studying it myself as well.

Band conditions have just been horrendous this past week. After my poor showing in the CW SS contest on Saturday, I decided to take a day off on Sunday, so I didn’t even try to get on the air Sunday. When I did finally get back on Monday evening, I found that there had been a coronal mass ejection (CME) and that the shortwave bands were almost completely blacked out.

It was so unusual that I got on our 2m repeater and asked if there was anyone monitoring who could turn on his radio and confirm my observations. Jeff W8SGZ was listening and did indeed find exactly the same thing I did. I could hear just a couple of signals, and I didn’t even try to make any contacts. Tuesday was a little better, and I did manage to eke out a few contacts, but the band was still very noisy.

Thursday, things seemed to be a bit better, and I made a few good contacts, although in the evening, the band started acting a bit funny again. I had a QSO with W4MQC in MA, and usually we have a pretty good QSO with strong signals. Last night, the QSO started out well, but Alan noted that the band had been up and down. Sure enough, after a few exchanges, the band changed again, and we had to cut it short.

This morning, conditions were lousy again. Several of the propagation websites (see below) reported that there had been another CME on November 10 and that we’d be feeling the effects on November 12. Well, they were certainly right about that. Fortunately, they also forecast quieter conditions for the weekend.

Links

• HF Propagation Falling Victim to Strong Solar Winds
• DXLC Solar Report
• WM7D’s Solar Resource Page
• Tad Cook’s (K7RA) Weekly Propagation Reports (ARRL)