Radio, railways, stuff...

I finally got myself a handheld satellite antenna - an Arrow II. It packs away quite small and is easy to put together, albeit you need to remember the size of the 2m elements when waving it about if constructing indoors like I did first time. I got the one without the diplexer because I plan to use two handhelds for full duplex rather than acquire a full duplex radio. Of course, the first order of the day was to try to bounce APRS off the ISS, in which I failed while waving said antenna about the shack. I received APRS easily enough but it was just too hard to try to track the ISS from the shack. I missed the good pass because the FT2D was refusing to see the GPS and I had not stored local coordinates - I have now. So, day 2 and I assembled just the 2m elements outdoors. Turned the FT2D on and it found the GPS almost immediately. I wonder just how much lead paint is on the shack walls! After figuring out where the ISS was on what was quite a low pass for us I picked it up and, finally got a call in. The following are screenshots from ariss.net: The actual 'raw' data as reported on ariss.net was "20210414100126 : M0RVB-7]USUPTS,NA1SS*,WIDE2-1,qAU,DB0NU-10:`w?pl [/`Hello from IO93_(" Next time I will try to reply to APRS 'calls' but this time was just a trial run to see how many arms you actually need. I can well imagine the complexity of tracking and calling through a LEO satellite, and logging as well. Anyway, this harness, which came via Amazon and was only just over £8 may work... not properly adjusted yet but seems to fit the bill:

So I now have a functional Creed 75 teleprinter. The person it came from had done a first rate job at cleaning it up and getting it to function. Thus far all I have done is put it in the workshop waiting for me to make some time and space to have a play. I also need to get my head around it as I have never had a 75 before. And here it is. It is in good shape given how old it is and I hope eventually to be able to sneak this into the shack, aka the little bedroom. There is just no way the 444 would hide in there but there is almost a 75-sized hole. The innards do look neat and care has been taken in getting it working. More to the point though it prints just fine, a stage I have yet to reach with the 444. The first order of play is to get some volts onto it via the TDMS and make sure it receives as well as sends. Ah, that means I need to fix the TDMS which has stopped working. This also means I need to rearrange all the valve collection as this is taking up half the workshop right now. Snowballing...

I thought it would be a useful experiment to make up a 23cm groundplane antenna. There is a useful guide at https://vk1nam.wordpress.com/2017/06/24/23cm-14-wave-ground-plane-antenna/ Using some 2mm copper wire from a supplier on eBay plus a N-type female socket the construction was fairly simple. Using the dimensions given above plus a bit for fiddle room I soldered the vertical element to the centre conductor of the socket. For the radials, given it was copper wire I decided to press my jewellers anvil to work and flattened the end of each element sufficiently to drill a 2.5mm hole. Using 2.5mm bolts each was secured to the respective mounting hole in the socket, and then the excess thread was cut off with a Dremel. Bringing it all indoors - the heavy stuff like drills and hammers live in the workshop - I calibrated my NanoVNA and gave the new antenna a go. It was a bit off but then each element was too long. Trimming each gave a fairly flat SWR where I wanted it. Well, almost, but near enough to stop cutting bits off! But does it work? Yes, I can open up GB3WC from the shack holding the antenna up inside the window. It’s about two S-points down on the Yagi, or anyway two of whatever the divisions are on the signal strength meter on the FT2D. Surprisingly I can get into the repeater with the antenna on the desk, albeit only coming alway up the signal strength bar and very hissy. It was the same when sitting the antenna in an old bottle as a support - at that altitude there are a lot of houses and trees between us and the repeater. For a bit of copper wire and a socket it was a fun little thing to make. I actually planned to make a collinear and may still,  but this was nice and simple and quick.