In my previous article I mentioned putting up my old multi-band inverted vee as an interim measure to get me on 17, 30 and 40 meters while the big tower project is ongoing. My immediate goal was 3C0L. I did work them on several bands though not as many as I'd wish since I gave priority to tower and antenna work while the weather continued to be pleasant.
In the process of cracking the pile ups on 3C0L and others I thought it interesting that I was using 3 distinct operating techniques depending on the pile-up depth, propagation and the competitiveness of my signal. They can be used by anyone, from little pistol to big gun, and they are used.
The purpose of this article is not so much to reveal anything novel other than to categorize them in a way that can help the DXer choose how to approach each pile up. If you've followed this blog for awhile you'll know that in my QRP years I wrote several articles on cracking pile ups with a tiny signal. It seems worthwhile to add this one to complement what I've written earlier.
#1: Predict where the DX is listening
This is the most common technique and is widely understood and practiced. There is no need for me to repeat here what everyone knows. If you use it you'll know that sometimes it works well and other times not at all. The difference in results often comes down to whether your signal is competitive with others in the pile up.
Competitiveness is not only about antenna and power. With the best station in the world you will be beat out if propagation favours another region of the world. For us in eastern North American that is most often Europe. For example, with a low solar flux north-south paths are better on the high bands. That puts North America at a disadvantage compared to Europe for working 3C0L. Even small stations in Europe will outgun you.
However if you are competitive in the pile up and you are good at predicting the DX operator's pattern you will soon have the QSO in the log. Prediction works well much of the time.
#2: Call where others are not
When you are not competitive your skill at predicting where the DX is listening will most often lead to frustration. Many others can predict as well as you and your signal will be underneath theirs. You'll end up frustrated as you fail to be heard. Those with little signals know this feeling all too well; it's a part of the game. Another strategy is required.
In the past 24 hours I used the following technique twice: to call where others are not. The first case was 3C0L on SSB. They chose to work stations by numbers. I'm too busy to sit near the rig to wait for them to call for 3's so I kept missing an opportunity to call. When I was able to call the pile up was huge and in the few minutes they worked 3's I was unsuccessful.
Catching them one last time on 20 meters before they shut down (14.190 MHz, and listening up 5 to 10 kHz) I did the prediction thing for a couple of calls before realizing this was unlikely to work in the few minutes remaining. So I listened to learn where others were calling. The vast bulk of the callers were on 14.195 MHz, the frequency of the previous QSO -- there are lots of predictors out there! There were a several callers on 14.200 MHz and only a few in between.
I picked 14.1975, right in the middle of the pile up range, and made my call. No one else was heard on that frequency. It took 2 or 3 calls until he QSY'd and found me. Into the log he went. The mass of predictors then made their call on my frequency.
The second example was FT5WQ/MM on 40 meters CW. This is not a country, just an opportunity to practice pile up technique. With the inverted vee rather than a yagi, and no amplifier, I was not competitive for the size of pile up. Prediction didn't work for me. So I delayed a second when he solicited callers and tuned the VFO to where I heard silence. Again, it took 2 calls to put him in the log.
This technique works because even the most dedicated DXpeditioner gets fatigued from constantly trying to pick a call sign out of dozens or hundreds of overlaid signals. Eventually they make an unpredictable turn of the VFO to avoid the predictors. When that happens they'll usually stop at the first isolated signal they find. That signal can be yours.
#3: Uh oh, where's the pile up?
The first two techniques can be succinctly stated as calling where he's listening and calling where others are not transmitting, respectively. But what if you can't hear the pile up at all? This happened to me with 3C0L on 10 meters CW. He was working mostly Europe and a few in North and South America. Evening was crossing Europe and the propagation gradually favoured this hemisphere.
From VE3 I heard not a whiff on any of them, not in Europe and not in the Americas. Prediction was impossible. I didn't know where he was listening or where others were transmitting. This is a dilemma. This brings us to the final technique: to call blind and hope for the best.
Despite the lack of signals there was one source of information, marginally useful though it was: the DX spotting network. Occasionally the DX will be spotted with the frequency where he was worked. I saw one of these timestamped a few minutes earlier. That makes the information old. Yet it was all I had to go on. That one said listening up 3 so I called up 2.5 kHz.
Despite calling blind I actually got through within a few minutes. I was monitoring the spots and would have tried a new offset if someone mentioned one, but no one did and I stayed where I was. I returned the favour by spotting my offset to work him.
Although a poor strategy in most cases don't hesitate to use it when all else fails.
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