woensdag 29 november 2023

DXCC 319 : TX7L Marquesas Islands

Contacted and confirmed TX7L, Marquesas Islands. A seemingly easy country, however, took 28 years to contact and almost didn't happen again. With only the OB1-30 available, it was a matter of waiting for the right moment on 30m. Luckily, at the right time in the shack and in CW, I could operate without issues.

Unfortunately, due to the same antenna problems, missed Temotu and North Cook Island. Very disappointing

dinsdag 28 november 2023

160m and CQ-WW-CW contest SOHP-A-160

After the euphoria of the Bouvet expedition, activities have dropped back to zero. And I paid for it in cash: two out of three motors of the Steppir are no longer functioning. After opening up the motor boxes, I managed to get the driver back to work, but the second motor was completely stuck. Ordered a new one from Steppir (excellent and fast service, by the way, so unfortunate that there are no dealers in Europe anymore), and in the coming weeks, I will try to mount it again.


Steppir : metal strips are still looking like new even after 20 years



So, onto 160 meters.

With 76 confirmed countries, there is still a lot of work to do. 10-band DXCC gets the highest priority at this moment. During my first tests of the wire antenna last week, I had significant EMC problems. Because the Flexradio is directly connected to the internet router, I managed to crash the router with the slightest power, causing all kinds of consequences. I was warned that the 1:2.47 unun, which ensures the correct impedance, plays no role as a current balun. I did experience the same kind of problems in 2022 but not so frequently as this year.

Two solutions implemented : first, I connect the radio to a separate Wifi booster, to avoid a physical connection between the radio and the router.

Secondly, I quickly ordered an MFJ 915 choke from Wimo (also very fast service), and now all problems seem to be solved. The only drawback is the limitation of 1500 W (outgoing and returning power combined). Because of that, I use power in the range of 800W-1000W. Better to use a bit less power than to risk a broken system.

160m CQ-WW-CW contest


Two adjustments for the 160m contest this year: I installed only 12 radials due to the suspicion that there are enough reflections available in the extremely wet ground. The antenna, still an inverted L with a vertical leg of 15m and a horizontal section of about 17m, was carefully trimmed to resonate at 1824 kHz, just okay for a good SWR between 1800 and 1850 kHz (so that I can smoothly operate FT8 later this year).



The second adjustment this year is the focus on reception. For this, I installed the necessary hardware back in August. The Ameritron RC4 switch, powered through the coax, serves as the heart of the receiving system. Connected to it is a 60m beverage-on-ground that I had successfully used last year. But this year, I've also added 2 K9AY-style single loops that are oriented towards the Caribbean and the US. The fourth position was intended for a beverage antenna, but it didn't happen this year.

I use the simple loop by qro.cz and the 160m design. This means lower (only 5m) but wider and more wire used in comparison with the normally used K9AY.





The decision not to go for a complete K9AY setup is twofold: I didn't want to bother with additional multi-wire control wires because I don't have enough free positions to the shack and didn't want to mess with the rotor and Steppir control wires. I had planned a relay circuit for switching direction 180 degrees with just two a 12DC and ground wire, but due to bad weather and especially lack of time, it didn't get installed.

Secondly, I can later use these two loops as a two-element broadside/endfire array in the hope of achieving an equivalent result without having to install a beverage.

Regarding the operation of the receiving antennas during the contest, here are the observations:

  • - With one exception, the transmitting antenna was always worse in reception than the receiving antennas. Without a separate receiving antenna, I don't start any contest on 160m.
  • - The loops subjectively provided better reception, and the BOG seemed more directional.
  • I had hoped to disable the reception of European stations towards the Caribbean, but this did not work. The Caribbean was pure chaos again this year.
  • - Towards the States, I needed the loop; with a vertical, it would have been hopeless. I made very nice contacts like AA7A in zone 3, but the reception was just a bit too weak, resulting in losing many points. The difference with stations in the Top-10 ranking is that a beverage towards the States is necessary, given the many points to be earned.

The contest:

I had set a few goals, knowing that due to good propagation, many people were not going to use 160m. As always, trying to work new countries, especially the Caribbean. Secondly, testing the receiving antennas. Thirdly, achieving a better score than last year. A top score in ON is almost impossible since the top-10 positions are occupied by ON4UN, ON4WW, and ON4IA, all stations with multiple beverages and arrays.

The biggest successes occurred just before the contest and at the end of the contest. When testing on Friday evening in FT8, I worked 7O73T. On Sunday evening, I was called by 4W8X. At first, I thought it was a pirate, the signal was very strong, but meanwhile, this QSO has been confirmed. In between, I can add C3 and ZF1 as a new country, and I attempted to contact A60A. The status of this qso is still uncertain."

The inverted L performed very well. I made it through everywhere. 800W was sufficient for me because I wasn't strong enough on reception. On 160m, reception is everything!

But the weakest point this year was the operator. The preparation for the contest was dramatic. Tired, no time, and especially insufficient CW training. I usually practice a few weeks in advance with Morserunner and Rufz, but this year it seemed inadequate. I was unable to pull stations strongly from the noise, had to ask for repeats several times, and lost a lot of QSOs as a result. Moreover, I had to take a 3-hour nap on Saturday night. The concentration loss due to fatigue was too significant, and the risk of penalty points increased. When my body calls, I have to listen, unfortunately.

Despite all this, I still made 830 contacts. The strongest strategic choice was to manually change the direction of the loops on Sunday, giving me three receiving antennas pointing east. I stopped at 21h UTC on Sunday for practical reasons. Next time, I need to be able to take Monday off.

All in all, I am very satisfied, and this gives hope to work the last 20 countries for 160m DXCC. Being present in the shack is key, and this is a weak point for me. Everything has to happen over the weekend...

setup before the contest, FT8 testing...