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I am surprised that I actually managed to do something useful today. For a while now I have been meaning to put a Cross Country Wireless HF/VHF/UHF antenna splitter to use and today was the day. It is now sat upside down on the top shelf above the radios, fed from the discone in the loft and feeding two little LoRa modules, one for TinyGS and one receiving radiosondes. The TinyGS receiver had been running for some time sat in the loft and was previously the only thing connected to the discone. The radiosonde receiver had a 70cm ground plane in the shack and never received anything. Since reorganising the feed it has burst into life, rather surprisingly finding a balloon quite close to this QTH which was apparently launched from somewhere to the west of the Lake District but the data does not show the launch site. Looking at the altitude figure in the data I suspect it is already sat on the ground. Pity I cannot go out right now to see if I can find it. Now, the cabling is RG58 and so not particularly good at UHF. The next step is to put a pre-amp next…

Well I fiddled with the teleprinter some more, wondering if I could at least get it to print with just 30-0-30VDC - it needs 80-0-80. Nothing. I tried connecting directly to the relevant pins for the receiving relay but could not feel any resistance when this was applied. Odd, because I could measure its resistance with a multimeter, so what's up. Strangely the next time I tried I could no longer measure the resistance. Might have been me. Then it occurred to me that on the 444 everything comes out on the 50-way D connector and you can get directly at the receiver coil, and I can see the relevant ohms. So, re-wiring the lash-up and still with 30-0-30V and with a resistor in series just in case and it burst into life. Almost. It did print, or rather tried. It got most of the letters wrong, but is at least trying. Most likely the voltage is just not quite enough, or my lash-up resistor is denying it sufficient current but I'd rather not risk the coil right now. However, and more of a concern was that although it went through the motions, the carriage did not move. It was…