If you’re not a radio amateur you will probably find this boring and mostly indecipherable. If you are a radio amateur you may also find this boring and mostly indecipherable 
I’ve made some more progress. I’m back on packet (AX25). It took some work to get going again, not least because there aren’t many packet stations left running. The local BBS was off air after a computer failure and I couldn’t hear any other stations.
The BBS Sysop got his end working but couldn’t hear me very well. That proved to be a very lossy bit of flexible coax I’d used between the radio and much thicker (RG213) coax. Having fixed that I still couldn’t hear his station at all. He had it working locally but there was no signal reaching me. After some diagnostics I discovered that if I parked outside his house I could hear the signal but it was pretty much noise half a mile away (and I’m a mile and a half from him). I visited him today to check his cables and antenna (SWR testing). SWR should be close to 1:1. Higher values, e.g. 2:1 are worse. That means a lot of signal is being reflected back down the coax and not being transmitted by the antenna.
A quick test of his coax+antenna gave a SWR reading of 4.6:1 which is basically disastrous! He’d added a short extension cable recently so I resoldered the ends of that and got an SWR of 1.1:1 (good) for the extension. We put the antenna+longer coax back onto the extension and were back to 4.6:1. We’d suspected the extension because it was the new bit.
We went to test the long coax + antenna and in connecting the tester (a nanoVNA for those who can decipher my radio ramblings) the N-Plug on the end of the coax fell off in my hand. We were pretty sure we’d found the source of the problem. We fitted a new plug and re-tested. The complete coax+antenna was 1.15:1 which is very good.
Once I got home I could now hear his signal so I just needed to tweak my transmit and receive audio levels. They’re not perfect yet but they’re good enough to sustain a connection between me and the BBS. I’ve sent my first packet message since 1997 and explored a bit of the surrounding packet infrastructure.
If there’s anyone still using packet then if you’d like to you can send me a message at:
g6fci@gb7esc.#16.gbr.euro
I’ve also started to experiment with WPSD to replace Pi-Star (which is no longer being developed). I’ve got it kind of working but there’s something wrong because incoming conversations make a nasty digital noise rather than some actual speech. I need to investigate further because it’s not usable in it’s current state.
That’s all my radio ramblings for today.