Radio and rails...

M0RVB

More ISS SSTV

I managed a couple of rather poor grabs from the ISS SSTV event of the 28th and 29th January. Nothing to write home about, my setup is not suitable being simply a loft mounted colinear. However, this one fragment was interesting because when received the ISS was over the middle of Poland. Not too bad for around 800 miles or so. In fact, I received another fragment after this... And two further grabs on the 29th, the first over the English channel and the second as it passed over Poland.

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M0RVB

Snow effect

It's snowing fairly heavily here today and I wondered what effect, if any this would have on my QO100 reception. Very little it seems. There is no loss of signal strength when viewing the lower beacon, but the noise floor has raised a little. There's not a great deal on the dish but then it's pretty much vertical. There is a wedge of snow at the bottom of the POTY rain cover. Clearing the snow off made no noticeable difference to the signal. It's snowing less now and still nothing noticeable. I need to compare with a clear sky... which we had the next morning. There is actually very little difference, the noise floor appears better but it's very hard to say by how much and indeed if this is even real. The signal strength appears very slightly better. Without proper measuring methods it seems the snow and ice made hardly any difference.

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M0RVB

SSTV, DRM and QO100

A combination of things finally came together. I’ve never played with digital SSTV before, plus I had some time to fiddle about and wanted to see if I could decode some of the digital stuff from QO100. Finally, I received a couple of nice digital pictures of the Dakar rally from F6HA, neatly incorporating my previous main love of motorsport! My setup is far from perfect (read, a series of accidentally cobbled together bits): Windows 10 laptop running the excellent SDR Console and connected to my QO100 transceiver via Ethernet, audio mixer feeding from the laptop and to the Linux PC, and QSSTV on the Linux PC. There is a lot of noise in my QO100 setup that I need to figure out because it really messes up analogue SSTV and seems to have made these digital modes even more fiddly. This is probably not helped by the audio running round the shack. In an ideal world I’d have a decent Windows PC with two screens and a virtual cable. That needs to wait until we sort out what is to happen with an older PC desktop here as if it is to be replaced I will nab it and…

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M0RVB

More ISS SSTV captures

Two good captures early this morning, again on the FTM100DE and its co-linear. These are pictures 12 (received at 04:30 UTC) and 1 (04:47 UTC) of the series: There was another pass just now and I wanted to try the FT450D plus its 144/28 transverter and loft mounted horizontal dipole. A bit disappointing but the pass was a lot further south and the pic was received with the ISS still over the Atlantic. Anyway, this is number 9 of the series, received at 09:33 UTC:

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