Friday, May 04, 2007

What's the Frequency, Kenneth?

One of the questions I'm always asked by friends when I'm packing my gear is, "what frequency will you be on?" The short answer is, "I have no idea." I thought it might be good to spend a few minutes in today's blog entry talking about operating from that far away place.
Using common ham radio contesting terminology, there are two ways to obtain a series of contacts: search & pounce and running. The idea of running is to sit on one frequency and call CQ. You work somebody, close that QSO, and immediately solicit for another. The big DXpeditions (and contest stations) do this.
Search & pounce is precisely what it sounds like. You look for a promising signal on the band calling CQ and you respond (pounce on it) and hopefully they work you. Stations with smaller signals (called little pistols in contesting parlance) often do this and for good reason. Since a small signal is not heard everywhere, the ability to hold the frequency is compromised. If a small station tries to run it is likely that a big gun station (that doesn't hear the little signal) will eventually start using the frequency, pushing the smaller station aside.
Operating with this lightweight equipment, no amplifiers, smallish antennas, and often with temporary (and non-optimized) configurations means you will not be a big gun signal on the bands. The fellows with the 1500 watts (or more) and the stacked monobanders at 50 meters are going to always be louder. The question is really, "are you loud enough?"
I was worried about being loud enough while planning my trip to St. John in 2006. I had only a 100 watt transmitter and a very simple set of antennas. Let's examine just one of those antennas. It was a wire vertical 33 feet in length suspended from a fishing pole fed from the ground with just a single radial. Such an antenna works well on both 40m (quarter wave) and 15m (three-quarter wave). On this particular trip I made many 15 meter contacts. But how loud was I?
The 15 meter band is large enough that even a small station can run and I did just that. I called CQ. Sometimes I would make many calls of CQ without a taker. Minutes would go by and I would work just a handful. Other times I was working people quickly in a short-lived but intense pile-ups. Why? Was I loud sometimes but not others? That seemed unlikely. Nor was there any pattern geographically that I could discern. I worked stations in these states and provinces in one very brief burst: PA, TX, OH, MA, TN, DE, MD, PA, ON, CA, MA, NY, OR, and PA. Something else was going on.
That "something else" was the packet spotting network. Upon my return home I fished out the spots made for my operation and plotted them against the QSO rate. A graph with that information appears below.

The graph plots time across the bottom and QSOs per 15 minute period vertically in dark blue lines. The green markers approximately mark the times when my operation appeared on the spotting network. The picture was now clear. When somebody would spot me on the DX spotting network there would be a flurry of activity. Operators were relying on the spotting network to tell them where to tune. Once they tuned to my frequency they worked me easily. I was loud enough. They just didn't know to listen for me until the DX spotting network told them to do so.
Aside from the comments we could make about the possible over-reliance on the spotting network, the interesting point here is this: when people found me, I was loud enough. Sure, I could have had a better signal with a better antenna or an amplifier, but even with the very simple, temporary, lightweight, and hastily constructed setup I was plenty loud enough.
Prior to the Montserrat trip I was asked, as always, "what frequency will you be using?" My response this time was, "watch the DX spotting network." This approach worked very well. The villa at Gingerbread Hill had an internet connection reliable enough to send mail, surf the web, and work the DX spotting network. I would begin each operating session by finding an empty frequency and calling CQ. After about a minute, I would spot myself. Then the floodgates opened. Usually, it took only one spot to "prime the pump". After that, everybody could hear the pile-up.
Self-spotting in a contest is bad form. I'm not advocating any bad behavior during contests. (In fact, except for my work at K1TTT recently, I've never used the spotting network in a contest and have no plans to do so in the future.) Self-spotting on a DXpedition is a fine idea. It worked exceptionally well for the VP2M effort and is an excellent alternative to trying to pick a frequency (or set of frequencies) prior to the trip.

All of the above is the precursor to a discussion I'll post about the mechanics of operating on the other end of the pile-up. In the mean time, look for me in the New England QSO Party this weekend. Oh, and don't forget to look for Steve (K9ZW) and his island activation this weekend.

One last thing: For the story behind "What's the Frequency, Kenneth?" see this. We live in a weird world.


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