IS0/EA8DBM (JN40eo)
IS0
The plan for tomorrow, August 28, is straightforward.
If the weather permits and there is interest, I'll be operating from Corsica until 8:00 local time. After that, I'll take a couple of hours to pack up and then travel 150 km to the port.
It will take about two hours to reach the port, with the ferry departing at 15:30. I’ll arrive around 19:00. In that case, I probably won’t have the energy to set up right away. However, if there’s no one to work with in the morning, I’ll try to catch the 12:30 ferry instead. That would get me there around 16:00, and I’ll definitely be ready for moonrise at about 23:50 UTC.
This is my 10th expedition, and I’ve gained some experience along the way. Here are a few tips that might make things easier for both of us:
1: If you’re a “Big Gun” with a dish 4 meters or larger and several hundred watts of power, I will definitely see and hear you. The only thing to keep in mind is to be aware of your surroundings and avoid sitting too close to someone else’s frequency.
2: The most common group consists of operators with a 3 to 3.5-meter dish and 250-500 watts of power. Generally, I can see you and you can see me, but occasionally I might miss you. If that happens, it’s a good idea to let me know in the chat that you’re calling. I’m not always looking at the monitor since I have to constantly check on my “umbrella antenna” and PA, which are 20 meters away from me.
I have a loud “Beep” set up for any messages addressed to me in the chat, so I won’t miss your message.
To make it easier for me to find you, it would be helpful if you could tell me your frequency shift.
3: The most challenging but also the most interesting group consists of operators with dishes ranging from 1.8 to 2.5 meters, often using non-optimized TV offset dishes with 100-200 watts of power.
I typically won’t see your signal, so it’s crucial to let me know your offset. This will help me search for you in the right spot and prevent others from interfering with your signal.
If your signal is very weak, I’ll insert your call sign in the TX1 field and call you directly. In my experience, this often significantly improves decoding.
When calling from TX2, keep in mind that my parabolic antenna is very fragile and sensitive. Any gust of wind can alter its configuration, affecting both signal gain and direction. Even a small breeze can cause an offset.
If decoding fails, switching to 120-second D mode can be highly effective. However, I can only do this if the outside temperature is below 22-24 degrees Celsius. Otherwise, after about 70-80 seconds, my PA goes into protection mode and shuts down.
Finally, the most important thing is patience, patience, and more patience! On my side, it’s practically unlimited—only the lunar window can limit it.
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I was initially relieved by the absence of malfunctions with the TC, but something about it made me cautious. It almost seemed too smooth to be true. And, as fate would have it, my concerns weren't unfounded.
On the calm morning of August 29, with both the sun and moon visible in the sky, I set everything up as usual. I aimed at the sun—but heard nothing. I tried adjusting in every direction—left, right, up, down—but there was no response at all. This was particularly baffling because just before disassembling the TC, everything had checked out fine: ground was at 2 dB, and the sun at 6 dB.
Still determined, I attempted to call CQ. I managed to connect with four "big guns," but I noticed something strange. I was hearing them at 8 dB weaker than usual, and they all reported back that my signal was also weaker—by 8-10 dB.
2024-08-29,09:00:00,2024-08-29,09:02:00,DG5CST,JO60,1296.100999,Q65,-26,-22,,,,
2024-08-29,09:03:00,2024-08-29,09:06:00,HB9Q,JN47,1296.100999,Q65,-17,-23,,,,
2024-08-29,09:14:00,2024-08-29,09:18:00,NC1I,FN32,1296.100999,Q65,-20,-24,,,,
2024-08-29,09:58:00,2024-08-29,10:00:00,UA3PTW,KO93,1296.100999,Q65,-25,-25,,,,
I went through the usual troubleshooting steps. I replaced the LNA, made patches to the feed, and even swapped out the circulator, but nothing worked. My last hope now rests on Paul W2HRO. I'm hoping I can get a spare feed from him; otherwise, it looks like the expedition season might be over.
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This morning, I measured the SWR on both feed ports, and instead of the usual 1.08, it was reading 1.4. I also checked the noise levels: ground noise was at 1.5 dB, and sun noise at 2.5 dB. For those with larger antennas, you might still be able to make a few QSOs. I logged two QSOs:
2024-08-30,10:02:00,2024-08-30,10:04:00,ON4AOI,JO21,1296.100999,Q65,-24,-27,,,,
2024-08-30,10:10:00,2024-08-30,10:16:00,G4CCH,,1296.100999,Q65,-28,-22,,,,
However, during the QSOs, people in the chat started reporting significant fluctuations in my signal level. When I rechecked the SWR, it had risen to 1.8, which suggests a potential issue with the soldering inside the feed. I decided to stop transmitting to prevent any damage to the amplifier.
Unfortunately I have to stop the expedition due to damage to the feed. A new feed has been ordered and sent, but I will receive it only next week.
A big thank you to everyone who provided help and support:
Lothar DF2VJ for the donation
Dan HB9Q for the paid subscription
Dan N5TM and Petr AG6EE for the same-day shipment of the pre-owned feed for free
Paul W2HRO for sending the new feed on the same day
I hope to continue my journey by mid-September.