After some success with CQWW CW with the 10m Moxon, I decided to participate in ARRL 10m DX contest. It was held on Saturday/Sunday Dec 10th and 11th 2022.

Preparations

The day before the contest, I booted up my Windows computer that has the N1MM logger and PowerSDR. I connected the 10m antenna just to verify things are okay. N1MM was configured for the contest as well.

First day

I got up to the shack with a cup of coffee at around 7.00AM and heard some QSOs on 10m. It has been a rainy and cold weekend here in Bangalore. It was raining continuously the previous night. Since it is morning time, the asian stations were active, so I went up the terrace and turned the Moxon towards the east.

I mostly did S&P on the first day. At around 8.00AM, the noise floor went up by ~10db and I could only hear noise and a handful of very powerful stations popping out of the noise. It was very disappointing. I was trying to make contact with a very weak 4Z4 station when that happened. It was clearly some local QRM from someone's power supplies or sparks from electrical equipments as it was very broadband. The NB/NB2 algorithms on PowerSDR didn't help much. I tried fiddling with the NR2 parameters without much success. Very disappointed, I decided to wind up a bit and go and have some breakfast and come back. I came back to the shack at around 9.45 or so. The broadband noise was still there. But in a few minutes, it disappeared, showing the spectrum of literally hundreds of stations.

I quickly tried to make contact with as many stations as I can. At around 11.30am or so, I started hearing some russian stations, so I turned the antenna towards the North-West. Continued with S&P.

I had to step out again at around 1.15pm or so and had to get ready before that. I could come back only at around 4pm. I made contacts from 4pm to around 6pm and wound up for the day.

On the first day I made around 105 QSOs. It was all S&P. I made a mental goal of at least doubling that number on the second day as it was a relatively free day.

Second day

I started slightly early at 6.30am on Sunday and went up the terrace to turn the antenna back to the East. After some S&P, I found an empty spot and mustered up some courage and started to do a run (i.e. calling CQ). Calls started trickling in. Again at around 8.00am, the noise floor went up. I decided to take a break and come back at 9.45. And just like the previous day, the noise disappeared at around 10.00am. I continued the CQ run. By around 11.30, I made around 200 QSOs in total. I mentally aimed for a 500 qso run.. why not? Ignorance is bliss!

My homebrew 100W PA was getting hot and I was a bit scared of it getting burnt as it doesn't have air cooling yet. Temperature was less than 20℃ and that helped a lot. Whenever it was too hot, I took some breaks, sometimes, even turned off the radio for ~10 minutes. By around 4.30pm or so, I had hit 400 QSOs. After that I went slow as the fatigue had set in. I made another 40 QSOs mostly in S&P mode and decided to call it a day.

Conclusions

Overall, I am pleased with the performance and I am totally surprised that I could make so many contacts at all. I am attributing the success to the HPSDR rig's Rx weak signal performance and the 10m Moxon which performed really well.

I posted my scores on 3830 and uploaded logs into the contest website and into the LoTR. See you next year.