Thursday, March 12, 2015

13 db

In this past weekend's ARRL DX SSB contest I did something I have not done since returning to the air over two years ago: I entered a contest using more power than QRP. For the first time I put my recently-acquired FT-1000MP to work in a contest. Running 100 watts is 13 decibels more than the maximum 5 watts allowed to qualify for the QRP category. This is a brief recounting of how it played out.

I entered 15 meters single band since my time was limited and I expected to be competitive by focussing that time on one band. Based on conditions before the contest I chose 15. My choice turned out well. While the band was not open right through the night it performed well up to 3 hours past local sunset, and came up again with the sunrise. The solar flare on Saturday had little impact on me; it had more effect on those further west aiming at Europe and Japan through the auroral zone, and of course those in Scandinavia. I'm far enough east to have consistently good openings to Europe. That makes all the difference.


Unlike with QRP it is possible to make most QSOs by running with 100 watts. True, it is nowhere near as impressive as what a kilowatt and big antennas will accomplish, but still a very effective way to run up the score. It helps that in Canada we can operate SSB below 21.200 MHz, away from the wall of US super-stations. You could hear me and other Canadians lined up from 21.2 downward running Europe for hours on end. Some US stations called me down there, which I could not work both for being out-of-band and worth no points.

This strategy does not work for other areas of the world, even where they can operate SSB lower in the band. But other than Japan the possibilities of runs of stations outside Europe are slim. I did some limited running of JA in the early evenings, and I'd have done more if not for a new local QRN source that peaks to the northwest.

Another advantage of running is multipliers. While working Europe I had a number of callers from Africa, the Middle East and Central Asia. These are multipliers I otherwise never heard. I ended up with 97 countries, just shy of a weekend DXCC on 15 meters. About 10 of those are uniques that I would not have worked but for running. That's what 13 db buys you.


With just the one small yagi I am at a disadvantage when trying to work stations off the side or back. It costs time to rotate the yagi to work one or two Caribbean or South American stations when the bulk of QSOs are towards Europe.

As in previous contests I have some diversity in the form of an inverted vee hanging off my house-bracketed tower. The 40 meters element of the cage inverted vee has a somewhat complex azimuth pattern on its 3rd harmonic but does effectively fill the holes in the yagi's pattern. The strategy is to switch to the inverted vee to work those odds and ends that are not always worth rotating the yagi.

With QRP this often did not work out, and I had to rotate the yagi if I wanted the points. Add 13 db and I could make the needed QSOs on the inverted vee. In fact I could often work them when they were directly off the back of the yagi since the F/B is not very high. As I've stated before, this is reason to question the need for high F/B for contests. A notable exception is stations with multiple yagis per band which do benefit from high F/B, since unlike single-yagi stations they can simultaneously achieve diversity and QRM rejection.


Concentrating on one band means that you will at times exhaust the pool of available stations to work. If you have a kilowatt and a big antenna you can keep running, seemingly without end when the band is open to Europe by attracting (and hearing!) more of the majority who have small stations. That doesn't work for me, even with 100 watts.

For a all-band effort, as I always have done with QRP, it is best to make frequent band changes. This allows time for a rotation of stations to occur. When, for example, you return to 15 meters there will be a number of new stations to work. Even when the strategy is to run this focus on rotation can work well.

Rotation works since most stations are either single-operator or casual participants, and they can only be on one band at a time. Although this is increasingly less true with the emergence of SO2R entrants (single-operator, two radios), it is not enough to make much a noticable difference. By spending time away from a particular band, or even from the shack entirely, a different bunch of single-ops will fill the band as they QSY from band to band. The available pool of casual operators who will answer your CQ also rotates. You will benefit from this rotation whether you S & P or run.

In my case -- single band and intermittent operation -- my frequent breaks made rotation work for me. If I'd operated full time my rate would have suffered unless I were to operate all  bands. An extra 13 db can do wonders, but not perform miracles.

Working QRP stations

My small antenna and 100 watts was enough to attract quite a few QRP stations while I was running. They are easy to identify in the ARRL DX contests since, for non-VE/W stations, power is part of the exchange.

Some of the 5-watters from Europe, even far-eastern Europe, had good signals that were copyable through the QRM and QRN. Some were a struggle to pull through, but then so were many 100-watt signals. So while SSB QRP is a challenge it should not be dismissed as not worth the effort involved. Being on the other end I was only too happy to pull them through and earn the points. Hearing them also made me smile since I know what it's like to be in their shoes.

It also pays to listen closely to the weak ones as you S & P across the bands. I worked one multiplier this way, a VP5, who was running 5 watts. He was CQing to little effect. I heard no other VP5 that weekend, so it's a good thing I was paying attention to every weak signal I ran across.

On an amusing note someone mused on the N1MM Logger group after the contest about how to log the station who gave his power as 500 milliwatts. Apart from the logging challenge it goes to show just how far QRP (or QRPp) can go, even on SSB. The lowest power station I logged was running 3 watts.

The exclamation point

Later Sunday evening while exporting my contest log and reporting my results I tuned around 20 meters. I ran across the fierce North American pile-up on E30FB, Eritrea. Of course I jumped in. I was still running 100 watts. Mix pile-up tactics and a heaping load of good luck and I got through in only 5 minutes. That was the exclamation point on my +13 db contest effort.

Next up

I have no immediate contesting plan except, perhaps, CQ WPX SSB later this month. So after 3 straight posts about contesting I am likely to return to antennas in my next article.

I know from web site statistics that antenna articles are by far the most popular, especially those that are about a particular antenna and not on theory or other general aspects of the topic. Since antenna articles take some time I can't produce them at the rate of one per week. So you will keep on seeing many articles that are about other topics that interest me, such as the one you are now reading.

I intend to cover some more general points about vertical antennas that I touched one previously. This will set the ground work for specific antenna designs.

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