Five levels of encryption on the Australian Signals Directorate coin

7 September 2022

Sen, an all-round IT professional, writes about decoding messages embedded in the recently issued Australian Signals Directorate (ASD) fifty cent coin. While a fourteen year old boy in Tasmania is credited with making the discovery of four messages “hidden” on the coin, it turns out there is a fifth level of encryption.

The outer ring came close to looking like Morse Code and was giving some output that almost looked like real words, but just a bit too gibberish. After much banging-of-heads-on-keyboards we realised I’d transcoded the outer strings wrong, which meant of course we were trying to break codes that didn’t exist.

Note that Sen’s article contains spoilers, the messages are revealed in their entirety, so read it later if you still want to decode the coin’s messages yourself.