Radio, railways, stuff...

M0RVB

Allstar Link project

One of my ongoing projects was to build an Allstar Link node. I had acquired a working Baofeng 888 from eBay some time ago and a few days ago duly programmed it (all the channels in case I ever accidentally turn that switch) to the 70cm frequency I want to use. Also in the box of waiting bits was a Pi 3B, ex my Portsdown project (that has a Pi 4 now), a CM108 USB dongle and a dummy load. Anyway, it came to the top of the project list (= I wanted something relatively simple to fiddle with. The CM108 came from Amazon and only cost a couple of quid. They had four available, all of which are now here! Following the excellent guide (among other similarly excellent guides) at https://allstarsetup.com/modify-a-cm108-sound-fob/ this was abused into something ready for use. Next came the 888 modifications (all relevant information can be found via https://allstarsetup.com/allstar-mini-node-construction-details/) which went fine except the information I was reading did not make clear how one powers the radio. I figured that out. Note that the radio needs 3-and-a-bit volts so two diodes in series with the 5V line works ok here (I need to add another yet). Anyway, in the true spirit of let's cobble stuff together and see if it works, here is the node in all it's glory! Powering it up resulted in the expected flashing of LEDs on the Pi and no release of magic smoke. But all was not well. The first issue I encountered was that it was not opening up the Ethernet port. Scrabbling about for an HDMI lead the Windows PC monitor was pressed into service and the Pi seemed to be endlessly rebooting. I caught sight of a message saying the voltage was low. Odd, as it was powered by a 5A bench supply. Anyway, plugging it into a Pi wall-wart cured that. But I did not get the expected voice announcement of the IP address. However, as I still had the monitor attached I plugged a UCB keyboard in to do the initial setup. The setup failed at stage 1! The Allstar wiki gave a username and password that would not work. A bit of Googling threw up root / root (*) and that worked. After having gone through the setup all seemed ready to go. I am not yet sure of all the options so selected the default in a number of cases, but I did chose to invert the COS line. Google was not helpful here. I could see it was transmitting as the red LED on the radio would light but nothing was being received. A check, again, on the saved CHIRP config showed that I had managed to set the channels up as duplex with a 5MHz offset. I don’t remember how but anyway… I changed those, uploaded it to the radio and power cycled the node and it duly announced my callsign and it’s IP address. Woo. For now, it's all back in…

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M0RVB

More projects

Some aluminium arrived for a couple of antenna projects. This took a while as the first order got lost somehow and now they only sent part of what I ordered, but sufficient to make a start. The first ones are for 70MHz, a ground plane for 4m FM, so I can reinstall the AT588, and a halo. I can't fit a big wheel type in the loft but a halo will fit and replace the current dipole.

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M0RVB

ISS SSTV event

Not done very well at all with the current ISS SSTV event that runs from the 21st June, or with the previous event a few weeks before. So far, I have not one single decent image to show for it. Not sure why exactly, nothing has changed here. All I can think is the station transmits earlier, completing as it approaches the west coast of Ireland and so it does not start the next one until it is south-east from me. But I can't remember how it went last time so not sure if that is even a thing. Anyway, I submitted the 'best of the worst' image, which at least has a complete top and tail, but only a fuzz for the actual image of whatever it should have been. I could crack out the Arrow and go dancing in the garden. Maybe next time...

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