Tuesday, December 2, 2014

Going QRP in CQ WW CW

If you enjoy DXing, QRP or QRO, you owe it to yourself to operate the CQ WW contests. The activity level is phenomenal. You'll hear openings and work DX you never imagined possible. It's not that the ionosphere behaves differently, but that stations are active from places and bands, and at times of day that make it seem as if it's the contest itself causing the openings.

There is something magical about getting on, say, 40 meters and hearing DX from all over the world fill the dial. You can rapidly spin the dial and hear DX. It then only requires that you give them a call and start filling your logbook. QRP works nearly as well as QRO. Everyone is eager to work you. All you need do is clear your calendar for a few hours, lock yourself in the shack and turn on the radio.

The CW contest is of particular interest to the QRPer. It's all about receiver bandwidth and SNR (signal-to-noise ratio). It is therefore no surprise that my results in CQ WW CW this past weekend, and that of other QRP participants, far exceeded those in the SSB contest a month earlier. There is even a RTTY version of this contest for those with a digital interest, and where QRP can also be competitive.

I won't dwell on my detailed results here, and only refer you to the submissions posted on 3830. Instead I'll delve into several topics that I believe are more interesting. My station setup was the same as I described for CQ WW SSB.

80 meters

I entered the LZ DX contest the weekend before CQ WW CW to test out my DX capabilities on 40 and 80 meters, with an emphasis on the latter. I didn't make many contacts on 80, nor did I expect it. The ones I did log were difficult for me and especially for the other operator. Five watts to a loaded half sloper nestled within suburban sprawl is not a good combination.

That said, the dry run was a success in that is showed I could work DX on 80. Not a lot but enough to make a big difference in my multiplier total. To give you an idea of how my DXing progressed on 80 over the past couple of weeks here are my DXCC totals at key times:
  • At start of LZ DX contest: 3
  • At end of LZ DX contest: 7
  • At start of CQ WW CW: 10
  • At end of CQ WW CW: 26
It's a modest level of success, but success nonetheless. It helped that conditions on 80 were particularly good on Saturday night. My best opportunities came from following the sunrise line as it advanced across Europe, briefly enhancing signals levels of each European station by at least 10 db. I started with Russia and ended with Spain a couple of hours later. Then I looked south to the Caribbean.

Propagation

There are many subtle and significant differences in propagation between the SSB and CW weekends even though they are only one month apart. For one, the eastward openings to Europe and beyond on 10 and 15 are shorter: the sun rises later here and set earlier there. The high solar flux and quiet geomagnetic field could not fully compensate for the path's reduced duration. Since high rates to Europe can be sustained from here on 10 meters when the band is open it was important to be there in those critical morning hours.

Some bands were open around the clock. The 20 meters band never closed. But for QRP the lower signal levels between midnight and sunrise made this band a poor choice. I nevertheless did make some contacts on 20 overnight just to break the monotony of operating 40 and 80. That I could so at all was interesting.


The story on 40 meters was similar. Even well after sunrise many Japanese and Russian stations could be heard. At this time of year the darkness line is not too far to the north of Ottawa and solar irradiation of the signal-blocking D-layer takes more daylight hours.

While interesting it was useless to me since with QRP and a small antenna, and one that does not favour the northern direction, none of this DX was workable. The difference of -23 db with respect to a kilowatt, zero antenna gain, and a low-angle radiation deficit of -0.6 db/meter of antenna height (40 meters, horizontal polarization) form an insurmountable barrier.

Attenuation of signals on all bands was low. This is particularly favourable with QRP where every decibel is worth gold. Propagation made this weekend's contest one to remember. The QSO and multiplier totals of the big guns are truly remarkable.

Antenna diversity

In this contest I had more success with having two antennas on the high bands than I did during the SSB weekend. With the yagi pointed to Asia, Europe or South America I could switch to the inverted vee whenever I came across a US station and raise their signal level. After working each one I switched back to the yagi for the DX path.

This technique worked less well for DX. This was particularly noticable when beaming to Asia or Europe in the afternoon and early evening when the path to the Caribbean and South America was good. More often it was easier to work southward off the back of the yagi than use the inverted vee; since the inverted vee runs north-south those directions show lower gain. When that didn't work I turned the yagi south to catch the stations I missed. The band map and local "spotting" feature of N1MM+ made the process efficient.

Pile-ups

Getting through a pile-up with QRP is difficult but not impossible. I'll mention a few methods here, most of which I've discussed in earlier articles. In a contest this is most relevant to multipliers. Double multipliers -- zone and country -- are even more desirable. It is an unfortunate fact that multipliers for you are multipliers for everyone else, hence the pile-ups.
  • Second call: Unlike in day-to-day DXing the callers tend to toss in their calls once and wait to see who the DX responds to. Since not every one of those operators is a CW expert with the uncanny ability to pull out a call or even a partial call from a pile-up there is often a delay in their response. I look at this as an opportunity. I immediately send my call a second time (easy to do with a function key press). With QSK I can always cancel the transmission by tapping the paddle if I hear the DX underneath. Since a QRP signal is copyable when in the clear this technique is often effective.. Your keyer speed must be high for this to work since the window of opportunity is only one or two seconds.
  • Self spotting: Contest logging software like N1MM+ have a band map feature that automatically spots calls that you enter but don't work before QSYing. If there's a pile-up you can quickly flip back to the DX's frequency at intervals, either to check if the pile-up is smaller or even gone, or when propagation raises the signal level.
  • QRM blind calling: QRM is common in contests. Big guns, and even littler ones, are always on the hunt for a run frequency. The multiplier you are chasing will occasionally be obliterated by the sudden appearance of a "CQ machine" on near the DX's frequency. Now you can't hear the DX, and probably neither can most everyone else. Often it is the case that by the vagaries of propagation the CQer and the DX station can't hear each other strongly so the path is still available for your use. So toss in your call a time or two even though you can't hear the wanted station, and others are standing by for the QRM to clear. When it does, and you do it right, it's your call you'll be hearing. Be extremely cautious when you do this since you can become the QRM, even though your QRP signal is small in comparison to most others. But it can work. One notable success in this contest was to work a Pacific islander through the QRM of a negligent CQer.
I said it above and I'll say it again: use these techniques with good judgement! It is all too easy to cause problems for others when pile-up busting techniques are misused or abused. Please do not become a part of the problem. Even though you are less likely to cause problems for others as a QRP operator you indeed can still do so. Bad habits are also difficult to break so don't ever start.

Sending fast and slow

One peculiar behaviour I see quite often is operators that are seemingly incapable of grasping the idea that different situations call for different CW sending speeds. Too many (and contesters are some of the worst offenders) choose what they consider to be a suitable speed and never again touch the speed control. There are frenetic contesters who seem to think that the faster they wind up the keyer the higher the QSO rate. Others, often those with small stations, send very, very slowly, worried that otherwise they cannot be copied. Both are wrong. You should adapt your speed to every situation.

Even if your CW skills are not the best it is possible in a contest to do as the situation requires regardless of your ability level. The exchange is usually simple and short, with the greatest difficulty being the unpredictability of call sign suffixes. It is possible to get by in a contest with code speeds 5 wpm higher than you can comfortably receive or send. Try it and you'll see for yourself.

Early in the contest, when everyone's rate is high, it is best to send fast: 25 wpm or higher. You may be surprised at how well others copy you: contesters are often superb operators. If you are answering another's CQ you likely will have more than one chance to copy their rapidly-sent call. So don't worry if you catch ust part of it the first time.

Even if you believe your QRP signal is poor copy on the other end (often the case on the low bands) your first call should be relatively fast. If they can hear you but not copy well they'll let you know. Then you should immediately slow down, by a lot if necessary, to ensure good copy of your call and exchange. I often call at 24 or 25 wpm and slow down to as low as 16 or 17 wpm if readability is poor. Don't be shy about slowing when the situation warrants. Better to slow down quickly rather than slowing in small steps. You'll complete the QSO faster that way.

Later in the contest I tend to go a bit slower just to start things off right. There is less hurry as rates plunge after the first day of the contest. Other than the VFO, keyer speed was the rig control I used most often during the contest.

Running

As always it is S & P (search and pounce) that produces the bulk of contest contacts for the QRP operator. Or at least for the QRPer who is not a rare multiplier. I estimate my QSO split in this contest as 13% run and 87% S & P. Despite the challenges of running it is necessary to reach a high score. There is no other way to work casual operators who never CQ themselves. It also is the only way to boost the modest rate possible with S & P, unless you operate in "assisted" class where you can exploit the spotting networks.

My expectation that 10 meters on Sunday morning would produce the best runs was mistaken. I just could not get anything going despite the good conditions to Europe and the faltering rate of the big guns. Instead I was surprised to find that 15 meters produced good results. It is therefore important to try running at different times and frequencies until you find a combination that works. Don't give up too quickly since it may take a few minutes for the run attempt to show promise.

In one big run on 15 I logged 75% of my total run QSOs, working mostly Europeans through late Sunday morning. My net rate was only about 100 per hour but it contributed over 150 QSOs to the log. You'd be surprised how slow this can seem in the moment. It gets boring to spent most of the run time pressing F1 and listening to my own repetitious CQ. Occasionally several stations would answer and I'd have to pick out a call, or partial call, and quickly clear them before the ones waiting got impatient and moved onward.

I was spotted only twice in this run, in comparison to four times in my big run during CQ WW SSB. This I discovered after the contest when I searched the spotting network history.

QSOs versus multipliers

There is a helpful feature in most contest logging features that tell you the equivalent score impact in QSOs of working one multiplier. In my case this averaged out by the end of the contest to about 3.1. That is, working one multiplier is equivalent to working 3 non-multiplier stations. This is an invaluable tool to ensuring you do not spend too much time in a pile-up pursuing a multiplier. Pay attention to this number if you want to get the best possible score.

I didn't always pay attention to my own rule. I can be very squirrel-like when the DX is rolling in: I am easily distracted by shiny objects, in this case interesting or rare DX. As I trawled the bands for more, mostly-unworkable DX with large pile-ups I was very aware that my score was suffering. There was some guilt about this but I really didn't care. Having fun is more important to me than winning a certificate. So I persisted in unproductive activity. In the time it took me to work 3 more JAs on 15 or fruitlessly sit in a pile-up on a rare Pacific station I could have worked 30 stations on 40.

Your objectives and interests may differ from my own. Watch yourself, and the clock, if you are focussed on achieving a high score. Perhaps I will try to win one day but until then I'll do whatever strikes me at the moment as most interesting. I exclusively focussed on the score when I operated as part of a multi-op effort, where it was more important to me to not disappoint my more competitive teammates.

Finally...

My antenna construction this year was in part intended to make me competitive as a QRP contester. That goal has been achieved. Although better antennas would improve on what I've achieved in 2014, and could be made compatible with my present QTH, it is likely that 2015 will see only modest improvements. The bigger changes may be inside the shack.

I will continue to design and perhaps experiment with new antennas, though more as a technical challenge than with the aim of improving my operating results. The required structures that would deliver improved performance are excluded in the near future. These include a permanent and stronger tower for higher and bigger antennas, and radials for low band vertically-polarized antennas. There are considerations outside of ham radio that limit my horizons for the next year. Looking further ahead...we'll just have to see.

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