Amateur radio (250)

M0RVB

The cold of winter...

Yes I know it's not really cold here in the UK, especially having spent a few winters in Montreal. But it's damp... always damp. I had set up an electronics bench in the workshop but I was always conscious of the humidity. Recently it's been hovering above 80% and so I have finally given up the idea and moved the test gear inside. My original aim was to have the shack in the workshop but three things always stopped me: the fact that having a lot of relatively expensive gear in a wooden workshop in the garden is generally a bad idea; the humidity; and the fact that all my antennas are in the loft. So the radios stayed indoors, now joined by the test gear, which makes sense anyway. Plus there's more light 'up here' with a large south-facing window. So far, so good...

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M0RVB

Another band bites the dust

Well, sort of. On FT8 I mean. I just received a couple of transverters from the transverters store in the Ukraine. These are not the newer model with the TCXO but are cheap and cheerful. Yes, they do drift a little but it's a toe in the water for me pending something else later on. I already have the Spectrum Communications 70MHz transverter and that works nicely but these are small units when compared, so I got a 70MHz and a 144MHz one. I connected the 144MHz one up today and set the FT450D to 28.174 and immediately heard FT8 tones. I'd not even fired up WSJT-X but sorted that quickly and made my first 144MHz FT8 contact within 2 minutes of turning the transverter on - followed by one further QSO and an indication via pskreporter that I had been heard all the way in NI. Yes, I know this is a minor achievement compared to those of other radio amateurs but it's still a new one to me... I now plan to sell off some kit including the Trio TR-9130 which has worked well. The one thing I don't like about that set is the notchy and fairly…

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M0RVB

Fiddling with APRS

I've been fiddling recently with trying to receive satellites but without all the going outside and waving yagi antennas around... I've heard a few QSOs on DIWATA 2 and there is a very good pass in a day or so where I may be able to get a call in. This is using the Trio TR-9130 as receiver as it has a horizontal dipole connected, and the FTM100DE as transmitter, though so far without success on transmit. Anyway, I remembered the FTM100 has APRS built in and the ISS often sends and receives this in 145.825 and so I've been leaving the radio switched on. Today I noticed it did indeed receive packets from the ISS. I also downloaded UISS by ON6MU which seems to 'just work' - nice that, I downloaded it and ran it and it found the sound card and returned an APRS message on a later ISS pass. Oddly, the FTM100D did not decode that message (the squelch is set to 0). It comes with a module called SoundModem by UZ7HO which seems pretty comprehensive. Another package to play with...

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M0RVB

Boxing day

A minor project requires a metal enclosure so I got one off eBay. I have a 5V PSU and three Pi's to install to keep these all nice and tidy. The enclosure is sized to take the PSU and has ample room for the Pi's and a fan. The enclosure arrived and is surprisingly well made for the price. It has plastic surrounds front and back. The front and rear panels are held with screws and the top comes off. There are two metal runners inside to maintain the structure with the top removed. Not a bad little case. The only odd thing is the description. Apparently the features of the case are 'surface mounted', ok I expect this means 'sat on a desk', and 'underground electrical enclosure switch junction box'. Not so sure on that one!

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M0RVB

QO100 dish alignment experiments

After some fiddling I now have a decent amount of signal coming down from QO100, but also questions. The azimuth was already correct and I had adjusted that to maximum signal strength on a TV channel with a GT Media V8 Finder. But the elevation is numerically wrong, or the markings on the dish are wrong, which is more likely. Fiddling with elevation got the strongest beacon signal at about 26db and 26 degrees marked, but the AMSAT info says it should be around 23 degrees at my QTH. Mind you, for all I know the garage wall is not perfectly vertical! All SSB signals look good now except for one or two that are difficult to hear. However, having got that far, no adjustment to the position of the POTY in the arm or its skew make any noticeable difference, so I've left that one. Also, when transmitting a tone from SDR Console it actually peaks higher than the beacon so I had to reduce the drive appropriately. An SSB signal test showed very poor audio and no adjustments in SDR Console got it to where it needed to be. Turning the mic gain up in Windows itself cured…

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