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Thu 21 Sep 2023

Submission for October's ^Zine

Can be found on:

Issues 1 - 6 on ~loghead's webpage

Issues 7 onward on ~singletona082’s webpage

Heya ^C!

Like most radio amateurs, I’ve had some thoughts on how, in the event of disaster, we can get a good amount of information around our community and the countryside - Some kind of event like the bushfires experienced down the Eastern side of Australia in the ‘Black Summer’ of 2019/20, or as experienced in Greece earlier this year.

I first became interested in amateur radio around the time of the Arab Spring & Hurricane Sandy. Several north-African dictators ordered the internet disconnected. Hurricane Sandy proved that seawater and subterranean phone exchanges were a bad mix. Both of these events, happening at around the same time, had activists and organisers cut off from not only each other, but also news from the outside world.

I remember finding the response by those organisers to be astounding. Routers were being flashed with custom OpenWRT to become ad-hoc mesh networks, and some of these were connected to packet radio. Crucially, and where my amateur radio fascination started, north-African organisers used these radios to connect with other organisers in Italy & Spain, providing links for email exchange. 1200 baud isn’t a lot, but it’s more than nothing. Organisers in New York were able to simply extend the mesh to neighbourhoods which were still internet connected.

Then along came the ‘Black Summer’, and my mind started to move back to 2012. How can we manage real time communication in hostile environments, and provide updates about our community? What tools are available to me to do this, considering my limited budget? This is when I decided to become a licenced amateur.

Some of the lessons I took from the 2019/20 season were:

Telephone exchanges burn just as well as any other building in a bushfire
Fibre-optic can (and will) melt
VHF & UHF don’t like physical barriers – like smoke
VHF & UHF repeaters are connected together by the internet
We’ve built our entire communication systems around centralised spoke & node exchanges, with VHF & UHF backups
In one region of Victoria during 2019/20 all this infrastructure burned, leaving tens of thousands with no outside communication for some days

VK has many and interesting limitations on what an amateur is able to do with their radio, and one of these limitations is ‘no encryption’. Operating a link for regular email isn’t allowable, as TLS in VK isn’t allowable, making it effectively useless for my thoughts.

The thing I was thinking would most be suited to this work – Gemini – isn’t allowable, due to its use of encryption. That leaves us with either HTTP or Gopher. Either are fine, I guess. Here’s a vid by VK3FOX, looking at TCP/IP over packet radio [1].

JS8Call is an interesting project, which concerns itself with low-power keyboard-to-keyboard text messaging, which includes relaying. It’s used easily on 40m & 80m, making it more robust with smoke & other obstacles, and better for longer range work. This is a presentation by VK3GRK on how it works[2].

This is another vid by VK3FOX, showing BBS on packet radio[3]. I think there’s a lot of potential for this technology in times of crisis. I’m thinking that everything except Zork would be good in times of crisis.

And last, but by no means least, there’s CW & voice. I use software to ‘help’ me decode CW (I’m crap at it), and software can be used to make it a kind of keyboard-to-keyboard system, albeit without forward error correction. Sometimes the most simple technology is the most appropriate.

I think my next experiments will be software-aided CW over 80m, and setting up a BBS for use with packet radio – Which may be the most quintessential definition of the ‘Smol Net’. What also helps is I’m finding this super fun :)

[1] (HTTP, YouTube) VK3FOX’s vid on TCP/IP over radio

[2] (HTTP, YouTube) VK3GRK’s vid on JS8Call

[3] (HTTP, YouTube) VK3FOX’s vid on BBS over radio

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