Monday, November 10, 2014

One Gets Away

QRP DXing is difficult. Even though my DXCC results are quite good since I returned to the hobby in 2013 with a KX3 for a rig, it remains a challenge. That's a good thing. I always have to wonder (and sometimes I directly ask) why others feel a sense of accomplishment from working a rare one with QRO and a big (or not so big) antenna. All it takes is some dedication of time. You will get through.

There is nothing wrong with QRO DXing, and indeed I did so for many years and likely will again in the future. For me, at least, other than the low bands and 6 meters I got bored by it. I like to think there is more to DXing than country counting. When I do work a rare one with QRP I feel a sense of accomplishment that is missing from the DX exploits I achieved earlier in my ham career. Yet there are times when it can seem like a futile quest, that I am wasting my time in the pile-ups, getting few results.

If you're an active DXer you can probably guess where I'm heading with this narrative. No, I did not work the FT4TA (Tromelin) DXpedition. Although I did not expend a great deal of effort to work them I still did try for several hours spread over close to a week. I would have loved to work them, but I didn't and I'm okay with that. It's even possible that I did work Tromelin in years past, except that finding out would require digging through old paper records, a task for which I feel no motivation. If I did work it back then it would not have been with QRP.

I have discussed in the past how I have worked some rare ones with my QRP station. Now I will say a few words regarding the most likely reasons I did not work FT4TA.

Duration of DXpedition

While not a brief operation the rareness of FR/T meant that even those who failed to get through were still in need of it for an all-time new one (ATNO). My usual approach of avoiding the massive pile-ups in the early part of a DXpedition didn't work this time since the pile-ups did lessen enough to allow my little signal to be heard.

I may need to wait for a subsequent Tromelin operation to find more amenable pile-ups.

Stations spread across modes and bands

There appeared to be fewer simultaneous stations on the air in this DXpedition than some others. When spread across many bands and modes (CW, SSB, RTTY) this left fewer opportunities for me. These included both openings and band-mode combinations.

I have no good capabilities on 80 and 160; I could hear them but not work them on 80. I stick with CW since SSB is far more difficult with QRP, where power outdoes tactical intelligence every time. I do not operate digital modes. CW is my preferred mode, with the added advantage that it offers the best prospects for a QRP operator.

As a result the number of favourable openings (good enough for them to hear me, and when I am able to operate) on CW on bands from 40 to 10 meters were insufficient to give me a good chance. The best opportunities came on 30 meters. Yet I struck out even there.

Pile-up procedures

The DXpedition operators spread the pile-up over a large spectrum on CW, often from 15 to 20 kHz wide. This was likely done to help them pull out individual signals from the large pile-ups they attracted. Such a wide range is detrimental to those in the pile-up, individually, even if it allows more calls to make it into the FT4TA log. The reason it is detrimental is that intelligent pile-up tactics are less effective in this environment.

While there was a chance to practice zig-and-zag techniques, they worked less often. The operators tended to skip further and with less-predictable steps across the wide listening range they established. Sometimes I guessed right but mostly I did not. The same seemed true of other callers I heard. There was also a frequent random factor when the operator would jump to a frequency far removed from the just-completed QSO. It was especially difficult to figure out where they were listening.

It seemed that many callers took the easy way out of picking a frequency and making all their calls from there. I could have done the same, and did for short periods, but this is more gambling than operating. The more time to call the more chances you get, so time spent calling matter. However this is similar to buying more lottery tickets increases your chance of winning, where the absolute probabilities remain low. At best this strategy favour QRO.

The strategy of picking a reasonably-quiet frequency in the listening range is problematic. You cannot hear everyone who is calling the DX so there is no way to know if your chosen frequency is otherwise quiet at the other end. On most of the higher bands there is likely a multitude of callers from the US northeast that cannot be heard from my location. They will have similar propagation to the west Indian Ocean, and they are not running QRP. What you can't hear can hurt your chances.

Although spending more time calling can increase one's chances of getting through, this is not always true. For example, if your signal is below the other station's QRM or QRN level the number of times you call is poorly correlated with your probability of getting through. In the case of a DXpedition pile-up you also have to compete against the other callers. With QRP you are unlikely to be heard through the din, no matter how long you keep at it.

Back to antennas

I have completed construction of a loaded 40 meters sloper along the lines described in an earlier article. It will favour Europe. Since it is not yet raised I will defer saying more about it until it is up, has seen some use, and compared to the inverted vee. That should be done within the next week. This may be my final antenna construction project for 2014 since the weather is turning decidedly colder. It has already snowed once and more will be arriving within the week.

The loaded 80 meters half sloper has now achieved its first DX. If the 40 meters sloper works out it is likely that I will redeploy this antenna to optimize my capabilities on 40, which is in any case is a far more productive a band for both DX and contests with QRP. The problem is the modelled interaction between the two half slopers. It's about compromises. I can't have it all in a station this small, so 80 meters may have to be the loser in this antenna dilemma.

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