I operated "ham" radio since I was 15 years old, all with home built equipment and antennas. Yes, that first year was illegal .
I eventually ended up in a small Adelaide company and designed their solid state HF single sideband transcievers to commercial specs before I went on to other things. Another Adelaide company, Codan, is still making that type of gear to military specs, as far as I know. It could be a very useful backup if satellites are knocked out.
Sadly, satellites and mobile phones have reduced the attraction of that hobby these days. They were the good ol days waiting for the few days a year when the 52MHz (6 metre band) would open up to other Australian states, and at the peak of the sunspot cycle we got a few days every 12 years to Japan! Otherwise, 52MHz was mostly line of sight.
There's a heap of tech stuff I could get into but maybe over a beer sometime hehe.
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