Saturday, September 15, 2012

Weekend DX - And How Does The Afedri SDR-net Cope?

I drove to Kongsfjord Friday afternoon to do further tests of the 340 (alas, jury's still out and I don't know when it will return - if at all), and do some DX. Australia's been going quite well for several days, however for some reason only South Australia. The rest of the country is mostly absent, even the most common of them all, 4QD-1548. X-band has been exceptionally quiet.

Radio National 729 and 5AN 891, both in Adelaide, have had very nice signals, such as this one recorded at 17:30 UTC on 729 kHz. It was recorded off the Afedri SDR-net.

Conditions towards North America last night were mediocre, but enough to make a comparison of the dual 340 beverage, compared to two single 340's. A dual beverage has definitely more gain than a single one - average measurements suggests 5-6 dB or one S-unit. But it is more susceptible to Loran C noise too, and the F/B ratio has not been improved. It was impossible to measure if the front lobe had become narrower, which is basically the idea behind the dual beverage.

Some time ago I promised to get back to the Afedri SDR-net's capacity as a MW DX receiver. Could it really stack up with the much more expensive SDRs like the G33DDC, Perseus and NetSDR? Well yes it can. If I pay a bit attention to its somewhat fragile front-end, and reduce the VGA gain when necessary, there isn't much the other SDRs can do that the Afedri can't. It's a keeper. It has been appointed official DU hunter, and is connected to the 500 meter 50 degrees beverage.

I'm writing this Saturday evening, hoping to hear some North Americans tomorrow morning. Next weekend will see the inauguration of Bakker's MINI-whip to the MAX-Gain (21 ft) mast which was ordered a few days ago.

While waiting, I'm enjoying "Luftgitar" (Air Guitar in English), a rock program  on RAS-2 - via satellite of course.

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