Saturday, 20 December 2008

3B8GT, Mauritius

Ham radio has been slow here at VE3MPG. I do get on most mornings just to listen around and I work PSK 99.99% of the time. It’s just a lot easier than trying to decipher SSB sigs with my less than perfect ear.

mauritius_map1 I was on this morning just before lunch and heard VE3JW, the amateur station over at the Museum of Science and Technology about 24 Kms to the north of me. Darin, VE3OIJ was just signing with a station, 3B8GT. Had to look that one up; and quickly, after Darin’s final, I got a call in to that DX station. He responded with a 599 and he was strong here too with some QSB. 3B8GT is the island of Mauritius about 900 kilometres to the east of Madagascar and east of Reunion Island in the Indian Ocean. A good catch indeed with all of 20 watts reaching my Cushcraft R6000 vertical. I’m not really sure how much signal reaches the antenna as I’m feeding it with 100 feet of RG59 el cheapo coax. That’s 75 ohm coax, but my FT-950 swr meter tells me there’s no reflected power. Let’s say that less than 20 watts gets radiated. The Museum uses a beam but I was hearing the Mauritius station Q5 here.3b8gt

The op on Mauritius is Alexey 3B8GT with a very modest station according to his listing – 50 watts to a 3 element yagi. Conditions seemed to be perfect this morning but looking at the solar terrestrial data indicated the solar flux at 69, A-index at 2 and the K-index at 0. Not so good propagation it says. Nevertheless the actual working conditions seemed excellent at the time. Local temperature was –17C, crisp and sunny. When I signed with Alexey I hung around a bit to see who might work him but he called CQ for a good ten minutes and no takers. My strategy is to look for weak traces on the waterfall and try to work those stations – usually they turn out to be some good DX. Last spring I worked Reunion Island late in the evening on 20 meters using this strategy – it took me a week to snag him due to pile ups he was generating. That contact was using a 20 meter hamstick and 20 watts.

Another PSK31 tip:
Use the center of your waterfall. Testing will show that your transmit (TX) and receive (RX) will be strongest there. Don’t blindly use 1000Hz tone or strictly follow the VFO ‘set it and forget it' concept. You can easily lose 20% or more of your power on each edge of your pass band. Pass band centering of the signal will give the best results of both RX and TX.

CIA World Fact Book on Mauritius

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