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British naval signal and letter flags codified 1817. Morse code from 1840s. Ham radio still uses it when signal took weak fir voice. Proficiency was required f
by peter303 6y ago
British naval signal and letter flags codified 1817.
Morse code from 1840s. Ham radio still uses it when signal took weak fir voice. Proficiency was required for a ham license until 2006.
- CydeWeys 6y agoMorse may not be the oldest but my bet is on it being by far the most widely still used of anything nearly two centuries old. I got into ham radio a decade ago and learned Morse (poorly) just because. It already wasn't a requirement, but so many still use it.
- stjohnswarts 6y agoHopefully there's an app for listening to it and interpreting it? I bet those old timers get pretty fast with the Morse
- js2 6y agoIn my college comp-sci networking class, one of our projects was to figure out a system for sending messages visually between two parties spaced 100 yards (91 meters) apart as quickly as possible. Each team of four came up with their own signaling method, trying to balance how many bits were transmitted with each symbol with how quickly we could encode/decode the message. Binoculars were not allowed. We were outside, so we didn't know how windy it would be. I seem to recall on my team, we were sending two bits per symbol. I think it was just a large cardboard box, we colored each of the four flaps visually distinct, then unfolded one of the flaps for each symbol. I don't recall a single team thinking to re-purpose naval flags. Duh.
- Joker_vD 6y agoThere is also flag semaphore which is very fast and very recognizable and gives you about 5 bits per signal.
- alexhutcheson 6y agohttps://en.wikipedia.org/wiki/Flag_semaphore https://en.wikipedia.org/wiki/Flag_semaphore would have been good if you needed to send arbitrary text. Naval flags would be higher bandwidth if you could pre-arrange a modest-sized dictionary of the words and phrases you’d need. https://www.navalgazing.net/Signalling-Part-1 https://www.navalgazing.net/Signalling-Part-1 is a good read.
- js2 6y agoIt’s been over two decades but I think the requirement may have been an arbitrary bitstream but if not that, it was likely any of the visible ASCII characters.
- skeeter2020 6y agoBraille is originally from a similar timeframe and carries six bits. Modern enhancements have focused on the protocol above the payload to make it more efficient.
- anoncake 6y agoIf that counts, then so do Chinese characters (1200 BC or older)