Amateur radio ⁽²⁵⁰⁾

I am (still) gathering microwave test gear and have now acquired a rather nice HP frequency counter, good to 18GHz (but apparently tested to 20GHz). This will help once I begin constructing the numerous kits waiting their turn, in particular a 10GHz transverter. Microwaves have interested me since my school days, not because of school but because I remember being interested and being at school. Actually, the interest probably dates further back to me seeing various microwave towers around the place and my grandfather telling me what they were. Anyway, having something means trying it out... so here it is with a HT keyed on 145.5, and more interestingly to me a 6cm FPV transmitter held close by (until I realised it was getting hot!). The meter had not even warmed up for the 6cm test - me being impatient! Now, I just need a signal generator and a spectrum analyser...

I suddenly developed an interest in POTA and SOTA. Not sure why, I never seem to go anywhere other than the railway once a week, or shopping. But there you are. So far I have been active as a hunter and although I have only one confirmed QSO it's still more than zero. The QSO format seems to suit me too. I do prefer digital modes due to having naff hearing but this should get me onto the voice modes.

I've been meaning to set up something to generate a testcard via composite video for a while and, as is typical of me the ideal solution was sitting there in a BATC magazine on my bookshelf. CQ-TV No 270 has the details of one such setup using a Raspberry Pi Zero. I don't have one of those and Pi systems are hard to come by these days but surprisingly I had a 3B not doing anything. Software downloaded, 4-way jack to RCA plugged in and connected to a TV and, nothing. Well, a buzz. Checked the cable, all ok. Checked what the Pi wants... ...why does the Pi have to have the connections different from what appears to be a standard hi-fi 4-way to RCA lead? Or, rather, why does the hi-fi 4-way lead I have have to have different connections? Grumble. Ok. I wanted to test this seeing I had it all sitting in one of the bedrooms attached to a TV. Stripping down a 4-way jack lead that I never needed and which was far too short to be of use I made a lead. It would last probably half a second in normal use but worked sufficiently…

I grabbed one of these a few days ago, in part because there are a couple of dashboards for the telemetry of a couple of cubesats, but also because of the RF range vs the cheap SDR dongles I already had (SDRPlay RSP2pro excepted, not cheap and very useful, but also, not a dongle!). I failed to get anything off of AO-73 on a good pass via waving the Arrow II at the window - almost got it, just insufficient waving / pointing vs the window blinds, wall, shelves...! But the dongle sometimes dies. I read that this can be because of the USB post so I need to work on that - I have a powered USB hub to try. Anyway, another toy. Maybe it's time to invest in a reasonable laptop (the MacBook is getting old now and being a 15" model is a tad unwieldy) and go outdoors. Update: a powered hub seems to have cured the lock-up as I had the AO-73 telemetry dashboard running from mid-day on 30th to mid-morning on the 31st. It also stands the dongle up rather than it drooping in the socket when horizontal. No luck with AO-73 telemetry though...

I acquired a DTX1 DATV transmitter. Although this is rather dated now it is still a useful tx capable of transmitting between 350 and 1350MHz. As a test setup over my usual 6" or so transmission path here it is on 437MHz transmitting a test card (yes the test card is all wrong but at least has the callsign and it is unlikely to propagate beyond the garden). The test card is coming from a little device that reads an SD card (and other formats) and sends a selected image. I did try an old digital camera I have which has video output but which refused to do anything, not even when plugged into a TV. Anyway it proves the DTX1 works.