I thought it might be interesting this time around to address propagation from a contest planning point of view. Needless to say, my perspective will be heavily weighted toward operation from the area referred to, by the Society of Midwest Contesters, as the "Black Hole" - Wisconsin, northern Illinois, eastern Iowa and western Indiana. In order to decide what to look for from propagation analysis, we need first to define the problem. Let's assume that the operation is defined as shown in Table 1.

Table 1: Contest Parameters

1. Contest: Any DX contest (no value in W/VE QSOs)
2. Bands: All
3. Transmitters: Single
4. Power: High
5. Antennas: Rotatable beams on 7 MHz and higher, wires elsewhere

Thus, given the usual propagation parameters of solar flux and geomagnetic activity, we need to determine a beam heading and frequency for any time period in the 48 hours of the contest. There are additional constraints, of course. We want to maximize our score which means we want to have the maximum number of QSOs and the maximum number of multipliers. We'll look at these separately. Finally, we need to be concerned about the competition, although we can also learn a lot in real time from our competition.

Let's look at maximizing QSOs. Anywhere in the US, maximizing QSOs means concentrating on Europe and Japan, where the densities of contesting hams are the highest. And unless band conditions are very good, Japan is a distant second for the Midwest and the east coast. So in terms of running stations, our first priority will be to key on these two regions of the world. Europe is, of course, a very large area taken as a whole and, though you might not want to take time to do it during the contest, it is interesting to observe how the propagation in the morning from Europe begins with Scandinavia first and progresses through to southeastern Europe and the Balkans. After these two regions, perhaps South America is the next most active region during a contest, but the numbers of active contesters just can't match Europe or Japan.

In terms of the region with greatest density of country multipliers, it might be a toss up between Europe, which consists of many countries and a large number of active ham contesters, and the Caribbean, which consists of a surprisingly large number of very small countries, most of which are activated by contest teams launching large multi-multi efforts. From a propagation point of view, both of these sources of country multipliers are no-brainers. First, for QSO purposes we plan on strongly emphasizing Europe anyway and there usually isn't a strong need to search for new multipliers from Europe. The obvious exception to this is very rare European countries, such as the Sovereign Military Order of the Knights of Malta, that occasionally mount a strong contest effort. The reason that the Caribbean is a no-brainer is simply that propagation windows to the Caribbean are generally wide on all bands, the signals are strong even with poorer propagation conditions, and the operators of those efforts are usually superb. There is no excuse for not working every Caribbean country on every band in every contest. After these two regions, however, multiplier hunting becomes a more difficult problem and is an exercise involving some elements of luck, skill, and rotator fatigue.

What about the competition? From the Midwest, the competition to Europe is the east coast, of course. For the most part, there is only a brief period when the east coast has Europe while they cannot be heard in the Midwest. The paths and path lengths just aren't that different. There are enough stations for everyone to maintain pretty respectable rates. The competition from the western US for JA stations can be much more frustrating. The openings to Japan are much longer for western US stations, and contesters in the Midwest can listen for long periods of time to stations like W0UN running JA stations without actually hearing any of the JA station themselves. I'm sure the frustration is even greater for east coast contesters, especially if the polar paths are disturbed.

So how do you use this competition to your advantage? The fastest way to learn about conditions to any region is to listen to the stations that the competition is working and consider the rate at which they are being worked. It may just tell you stay on the band or move to a different band.

Okay, let's look at some examples. Figure 1 shows the propagation from the Midwest to Germany. This particular plot is from VOACAP for Windows and is the signal-to-noise-ratio at the required reliability (50%). The most basic approach to band selection involves considering the MUF (solid line) to be a band about 3 MHz wide. The plots indicate that we will probably get nothing on 10 meters, which is no surprise at this point in the sunspot cycle. The opening on 15 meters is likely not too long - perhaps a few hours around 1400Z. 20 meters looks good from as early as 1100 or 1130Z to as late as 2000Z. The rest of the time would be mainly spent on 40 meters, broadcast stations permitting, with a brief shot at 80 or 160 around 0500Z. Keep in mind the relative statistical basis of propagation prediction and use your ears more than the computer.

The situation for Japan is more depressing. Figure 2 shows the VOACAP for Windows signal-to-noise-ratio at the required reliability (50%) from the Midwest to Japan. The 20 and 15 meter openings are much narrower in time. The MUF stays relatively high, which means that 40 meter absorption may limit openings on that band to a short time around 1200Z. If the geomagnetic activity is high, polar absorption, which is important for the midwest US to Japan path, may dominate. An easily possible result is a 40 minute opening to Japan on 20 meters and little else. Contesting can be more fun during sunspot peaks, if not more challenging!

What about the rest of the world? It's much harder to be specific. The afternoon hours local time (1800-2100Z) are good times to look for multipliers from Africa, the south Atlantic, and South America but the rates are usually pretty low. In the later evening local time, after the Japan window closes on the upper bands, it would be good to look at south Pacific and VK/ZL openings. These are usually weaker signals and the beam headings are unique so you may not hear anything unless you actively go after them. Of course, you don't want to miss any opportunity to work any of the Caribbean contest teams. In any case, we are searching for multipliers so a lot of tuning, listening, and beam spinning is necessary. I usually work up an hour-by-hour band and beam heading plan with some specific options for hours when there is more than one possibility. After the contest, you can compare the plan with your actual rates to specific areas and fine tune the planning process for the next big contest.

All of this discussion was designed around active participation in a multi-band effort. If your real interest is understanding propagation and you are less enthusiastic about contesting, contest weekends still offer the opportunity for an amazing real-world laboratory experiment. Here are two example experiments. For the first example, choose a single band, like 15 meters, and then observe the contesting stations locations and signal strengths. You can simply monitor the band for a few minutes every hour. Spots broadcast on your local Packetcluster© node can be a great help for this experiment. Then compare the observed data with those predicted by your favorite program. In the second experiment, choose a single location, like western Europe, and hour-by-hour track signals from a single specific country on each band. Then make the same comparison with your software. Either of these experiments could be done as a participant or silent observer in the contest. And you'll learn more in a single weekend than you can otherwise in a much longer period of time.

Well that's it for this issue. By the time you read this, I hope to be back on the air after a seven month hiatus forced by moving. Look for either KA6A or K9USA in any of the cw or rtty contests. In the next issue, we'll look at another propagation software package and consider a completely different way of doing the path analysis for your ham station.