Monday, March 27, 2017

Struggling with CQ WPX SSB

CQ WPX contest is not a favourite of mine, especially the SSB weekend. The CW weekend, although more preferable to me, comes at the end of May when I'd rather be outdoors than indoors. Apart from the reasons I expressed in that earlier article here is one more thing I don't like about the contest.

Since prefixes count once and not once per band there is little incentive to pursue contacts on bands with marginal conditions. A quick review of top claimed scores on 3830 reveals little activity on 10 and 160 meters. There was nearly as little activity on 15 meters despite the presence of modest openings, including from here to southern Europe (EA, CT, I), and some good openings to South America. I heard many down south calling CQ on 15 with few takers.

Making it worse was a low solar flux that further concentrated activity onto 20 and 40 meters. The resulting heavy QRM limited the chances (and enjoyment) of little guns.

I put in a part time effort this past weekend if only for practice, to casually experiment with the station and operating technique and to ensure that recent repairs held up (they did). Not being serious in a contest is a good way to try things without worrying about the impact on your score.

Voice memories

I have used voice memories in SSB contest in the past. The KX3 has room for two messages in its on-board DVK (digital voice keyer). Because I was QRP the memory I programmed with a CQ was not very useful. The one I used most often was for my call sign. I sent that one a lot! The DVK was fairly easy to program by pressing lots of buttons and speaking into the mic connected to the rig. Levels and equalization were automatically the same for live voice and memories.

Editting of messages wasn't possible, making it vital to time button presses and recording to avoid silence before and after the message content. Macros programmed into the contest software (N1MM+ in my case) are used to simulate button presses on the rig to play the messages. This is a bit arcane but doable. I saved the function key file in case I decide to use the KX3 in a future SSB contest.

The FTdx5000 has an on-board DVK. Unfortunately it is, to be blunt, a joke. Too often manufacturers load up modern rigs with features that are unwanted and in any case are not designed for use in their intended applications. Again, there is no editting of messages. I can live with that. What annoyed me was playback.

The FH-2 accessory keypad could be quite handy to use the DVK. Recording isn't too cumbersome, once you get used to the sequence of buttons to be pressed. As with the KX3 and many other rig-based DVKs silence at start and end of the messages cannot be editted and so good timing during recording is mandatory.

Playback requires two button pushes and then activating the transmitter if you aren't using VOX since the rig will not automatically key the transmitter when a message is played. This is absurd and useless. What were Yaesu thinking? Indeed, were they thinking at all or just didn't care?

I therefore resolved to record messages on the computer and have N1MM play the Wave files (.wav) just as for CW memories using function keys. PTT is done with the WinKeyer interface, which offers perfect timing. This attempt was perhaps foolhardy since I haven't done software voice memories before and I undertook the task 3 hours before the start of the contest and only spent an hour at it. The experience was interesting.

In my first attempt I used N1MM's rapid programming technique of connecting the mic to the computer and pressing CTRL+Shift+Fn to record a message direct to a function key associated Wave file. It is similar in concept to direct programming of a rig DVK, with the same challenges. The played back files were noisy and the voice level was low. It seems that more work with sound card settings is necessary to make this feature perform properly.

I next chose to use Audacity, a popular free software application for recording and editting sound files. It is used by many contesters. I downloaded and installed the software and was soon happily recording and editting message files and exporting them to Wave files for playback by N1MM. Oh, if only it were that easy!

Playback requires connecting the output of the computer sound card to the rig. Unfortunately I am using a laptop where the mic and headphones jacks (sound card ports) are at the front where my hands rest. Although I have the integrated CAT/audio/data interface SCU-17 it is not yet installed on the FTdx5000.

The rig connection is as simple as a 3.5 mm Y-connector to join the mic and sound card into the mic jack. Not only did I not have a Y-connector in my junk box (I plan to order a few) I hesitated since I didn't know if the sound card output was AC or DC coupled. This matters since I wired the mic jack for my new headset with an electret microphone and it would put DC onto the sound card if there is no blocking capacitor in there.

Instead I routed the sound card output to the rear panel mic jack on the FTdx5000 which, according to the manual, is mixed with the mic jack on the front panel. Luckily I had a 3.5 mm stereo to phone mono cable in my junk box; Yaesu should have used a 3.5 mm jack on the rear panel.

That worked, sort of. The playback level was different from the mic and the audio didn't sound as if it used the same equalization setting I programmed into the FTdx5000 for the flat response mic. There wasn't time to trace the schematic and there was nothing I could do about it anyway just then. Instead I editted the sound files to add equalization and adjust the levels. Not being able to satisfactorily adjust these in time for the start of the contest I went with what I had.

When I set the mic level to best suit live voice the memories often clipped. During the contest a couple of hams helpfully informed me, thinking I had RF getting into the mic. I had to explain, briefly, what was really going on. Occasionally I gave up on the memories altogether to avoid the issue.

The experiment was instructive and pointed me towards what I need to do to get it right for the next time I enter an SSB contest.

Crowds = QRM

By concentrating most activity onto 20 and 40 meters the QRM was dreadful. SSB makes the problem far worse because of the bandwidth consumed. Unlike in CW you need at least 2 kHz separation to keep QRM managable even with the receive bandwidth dialled down to 1.5 kHz. Activity was so dense the separation was often only 500 to 1,000 Hz between stations.

There is thus little room for the little guns to run or to hear those lesser signals. The big guns were in reality not much better off since they had great difficult copying anything other than the strongest signals. The request for repeats of call signs and exchanges was routine, and rates suffered as a result.

It became comical at times. Here is a fictionalized QSO between me and a big gun. It is typical of some of my QSOs and many I listened to while waiting for my turn to call.
Him: "CQ contest QQ9XYZ"
Me: "Victor Echo 3 Victor Norway"
Him: "Victor Echo?"
Me: "Victor Echo 3 Victor Norway. Victor Echo 3 Victor November"
Him: "Victor Echo 3 what?"
Me: (repeat as above a couple more times)
Him: "VE3VN 59 1 2 3 4"
Me: "QSL. 59 3 2 4"
Him: "Your number?"
Me: "3...2...4..three hundred twenty-four"
Him: "381?"
Me: No! 3 2 4...3 2 4"
Him: "224?"
Me: No! 3 2 4...1-2-3 1-2 1-2-3-4"
Him: "Is it 3 2 4, roger?"
Me: "Roger roger roger!"
Him: "QSL. QQ9XYZ"
That final and successful method of communicating a serial number is sometimes known as horse counting. It is how purportedly intelligent horses answer math questions. For example:
Human: "What's 7 minus 3?"
Horse (stomping the ground with one hoof): clomp-clomp-clomp-clomp.
Very amusing the first time but increasingly aggravating when frequently resorted to in a contest to combat the ever present QRM.

One final note on QRM is that of F/B (or F/R and F/S). This is something I have sometimes lightly mocked since I am more often pursuing gain rather than directivity in my antenna designs. Yet this is a prime example of a contest when good directivity is useful to combat overwhelming QRM.

Often in contests there is some advantage in having only modest F/B so that stations in other directions can be worked without resorting to multiple antennas and frequently trying different directions, especially when running. It is occasionally useful in DX pile-ups as well so that the successful station can be quickly located.

In an SSB contest like this one with such intense QRM more directivity can be very helpful. My yagis -- short tri-bander and 2-element on 40 meters -- do not have great directivity. I will have better by this autumn. On 80 and 160 meters directivity can be less important in a high-efficiency transmit antenna if the antenna is supplemented with a high directivity receive antenna such a Beverage or 8-circle array. I used my Europe-facing Beverage even on the high bands in tough situations since it often helped just enough to make a difference, whether or not the station was in that direction.

Tragedy of the commons

Despite being called the dismal science, economics does contain many interesting concepts. One of these is useful for understanding CQ WPX and other contests: tragedy of the commons. In brief it explains how over-exploitation of a resource can occur by individual choices based on self interest. There is no need for a conspiracy to explain the phenomenon.

By over-exploitation in CQ WPX I primarily point to the unreasonable abundance of prefixes. As a result there is little reason to pursue prefix multipliers during the contest since you'll work new prefixes at a high rate by simply making QSOs. No one is special; when everyone is a multiplier then all QSOs are equivalent. Multiplier hunting becomes superfluous.

The implications on the contest are profound. The object becomes to work as many QSOs as possible, with only a preference for intercontinental and low bands for the higher QSO points. The bulk of the action is therefore between Europe and North America. Intra-continental QSOs are supplements to prefixes and QSO points. The rest of the world is largely excluded when yagis don't point their way. I heard many rare DX stations calling CQ without answers and even good signals from JA and VK had few takers.

Another example is power. To fight the incessant QRM inherent to an SSB contest during a solar minimum more stations are inclined to enter the high power class. That is, if you can't fight them, join them. When the majority do this the situation becomes the same as when everyone runs 100 watts: the QRM is the same and nobody really wins. It then comes down to who has the bigger antenna, a potential resource not so easily exploited by the majority.

One of the few reasons high power stations do so well relative to low power stations is that there are low power stations. Power can quite easily turn into another tragedy of the commons since amplifiers are easier to acquire and use than big towers and antennas. It can get uglier when ever more contesters choose to run illegal power.


Get used to a high level of QRM for the next few years until the solar flux resumes its climb. Consider it one more aspect of the challenge of a contest like CQ WPX and take comfort in knowing that everyone is dealing with it as well, from little gun to big gun. Contesting is a competition so don't expect it to be easy. Use the QRM as motivation to build better antennas and improve operating tactics.

Although CQ WPX has its unique problems that drive my dislike of the contest this is one aspect of it that will apply to many contests for the next few years. With sunspots the QRM will once again relent as activity spills over onto 15 and 10 meters.

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