2000 ARRL 10 m Contest: ZS6Z on Autopilot

Last updated 2001-01-23

During the 2000 contest season, I decided to make use of the solar cycle peak to try my hand at some single band contesting on 28 MHz. I pulled down my 80 m beam from its perch at 36 m, and replaced it with a long boom 7 element beam. I erected a separate vertically polarised spotting antenna, and integrated three receivers into a single switching system to allow the operator to look for multipliers while receiving. I also added switching systems to allow the operator to select any combination of four Yagis, pointing in three different directions.

I had good success in the CQ World Wide DX Contests. On RTTY in September, I came within 1% of doubling the existing world 28 MHz record, despite software problems. So far, no other comparable claim has surfaced, and it looks like a win is on the cards. On SSB, things didn't work quite as well, and I ended up claiming third place behind ZX5J and 5X1Z. On CW, it again looks like a convincing win. Conditions were not the greatest, and although my claimed score is above the world record, it's probably too close to stand up to the scrutiny of The Committee.

However, the station work and the contests themselves, combined with three university exams over the same period, left me feeling just a touch overwhelmed. There were many little niggling issues that didn't get addressed in that time, and that were crying out for attention.

It was against this backdrop that I had to think about the ARRL 10 m Contest. Its early December date placed it just after CQWW CW; perfect from a hardware point of view, but too close to have fully recovered from the contest season. I really didn't relish the thought of dedicating another weekend to radio. On the other hand, I would have loved to let the station flex its muscles and possibly even leave a new record that might stand until the next cycle.

Enter Koji Tahara, JM1CAX. Koji is now better known as JY9NX, but in other times he sported the callsign ZS6CAX and was audible on ground wave from my place. Koji is still studying through a South African university, and periodically has to stop by to deal with study arrangements. It just so happened that he casually enquired about doing the ARRL 10 m contest, just as I was coming to the conclusion that the contest would not happen. This was the solution to my problem! I quickly hammered out an agreement with Koji. These days, hosting a guestop is no laughing matter, as I live in the tiny little house where the station is, but Koji had been looking for an excuse to quit smoking, and we both thought we could coexist happily for the weekend. He preferred to use the Pretoria Contest Club callsign ZS6Z rather than his own ZS6CAX. I was happy, as long as he was prepared to send everyone a bureau QSL at his expense. Everything was set and done.

During the SSB contest, my FT1000MP's T/R relay had died on me. It was the first glitch with this wonderful radio after four years. I ordered replacement parts from Yaesu USA, but these were mistakenly shipped by air mail instead of express. By the time they addressed the problem, it was too late. I ended up doing the CW contest with the broken relay, but it was not the best fun I've ever had. I wrote to Koji, and he managed to arrange replacement relays out of Germany. They arrived in Jordan just a few days before his departure.

When Koji arrived at my place on Friday night, we spent some time doing dual on the station layout. Koji was rather the worse for wear, as his flight had been delayed and he had spent more than a full day in transit. I could see his eyes glazing over as I explained the use of the PTT-interlocked audio switching between the three receivers...

The Orion OR2800P controller for the rotator on the big Yagi also chose this moment to die. It was running haywire all over the place, and the only way to turn the antenna ended up being to look at it through the window and turn off the power when the beam came to its desired bearing. This exercise demanded some agility, as one has to cock one's head almost down to the carpet to be able to see the beam.

We spent the evening looking for the contest rules and finding the relay's location in the workshop manual, and Koji selected some Japanese delicacies from the menu of a local Oriental restaurant. We also had to install CT on my computer and get it running with the DVP. Koji got to bed just before midnight, while I slaved away into the early hours of the morning to replace the relay. Just removing the relevant unit and replacing the relay itself took the better part of an hour, but at least the repair seemed to do the trick. I also set up some targets for him to chase. We'd spent considerable effort trying to locate the records for the contest, but without success. ARRL Contest Branch couldn't help, as they were apparently in the process of re-doing the records. However, we checked the results for the past four years, and hoped that nothing bigger had survived from the previous solar cycle.

Koji got up around 05:30 local time (03:30 UTC). The band was already up and running, so he started up shortly afterwards to the east. By the time I was conscious again, he was in full flight. Koji's eyes stretched when I showed him the target: 3850 QSOs. No single operator had made much over 3600 before, and the skepticism was not hard to detect in his features. However, I pre-empted any contemplated lack of cooperation by simply informing Koji that he wouldn't leave the farm alive if he didn't make it. Fortunately, Koji isn't over-burdened with political correctness, and managed a wry smile in response.

I spent most of the day reading and sleeping, while QSOs continued to accumulate. Now and then, I would bring a cup of coffee, some food and the odd pat on the back. I would also bring the rate sheet up to date, and comment on his performance relative to target. Despite some early finger trouble, he was clearly getting the hang of operating all the buttons. Conditions were terrible, and it was tough going. By the end of Saturday, with 18 hours of operating in the log, Koji was 179 QSOs behind the target. He had been slipping behind the hourly targets throughout the day, and there didn't seem to be much that he could have done to improve.

During the night, I decided not to revise the target, but rather to wait and see what the morning would bring. He again started just before 06:00 local time, and by 10:00 local I was able to re-assess the targets. I decided to keep the hourly targets for the Sunday intact, but to adjust the cumulative targets downwards by 179 to compensate for the losses on Saturday. Koji still seemed somewhat apprehensive at the thought of having to make almost 3700 QSOs, but kept plugging away. After the first hour, he matched my target exactly. The motivational improvement was noticeable. In the following four hours, he managed to improve on the revised target by first a dozen, then 30, then 80, then 150. I drew a bold black line through the reduced targets, and informed Koji that he was back on the orginal target: 3850 QSOs. I also drew thick black lines through the continental records as they tumbled; first Oceania and Europe, later Africa. Only the Americas remained.

Two hours later, he was on track with the original targets. I called him at 23:45 local time, just when his allowed 36 hours of operating time expired. Koji was exhausted but jubilant. The multipliers were somewhat behind schedule, but with the QSO points being what they were, he'd passed P49V's score by just about 2%. According to the sources we had, this score seems to be the world record. It's hard to tell whether 2% is enough to survive the log checking process, but the heady feeling of beating the world record under indifferent conditions, and of breaking 3 million points, is not a total waste of time!

During the next few days, we watched the 3830 Reflector to see if any competing scores would surface. I noticed with some amusement that Koji had remarked on my "considerable pressure for a good result" in his posting. He'd obviously taken the death threat seriously enough...

Perhaps this is the way I should be contesting. I managed to read several hundred pages, rest enough for a change, spend much time in the kitchen, listen to classical music for several hours, go to church and even spend time chatting with my neighbour, and still saw a world record crumbling in the process. Maybe this guest-op thing is not such a bad idea! It's almost as much fun as the autopilot in the C402 that I regularly fly.

Bernie van der Walt ZS4TX and I are planning a Multi-Two effort in the ARRL DX contest next year (2001). That's another pastime I haven't tried. Maybe I should wait until I've tried that before I decide what to do with my contesting future. Perhaps that's even better!

As for the feedback from Koji on the contest hardware: He claims that he found six multipliers on the third receiver while transmitting, and that around 20 multipliers were found on the second receiver while listening simultaneously to the run frequency. Those don't sound like big numbers, but with a total multiplier of 250, they constitute almost 10% of the total score! Without them, Koji would have ended up well short of several of the continental record. Even with inadequate isolation, the spotting beam was clearly making a big contribution. Some development work remains, as none of this stuff can be bought off the shelf, but at least we seem to be on the right track.

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