Works with no internet. Turn words into Morse or Morse into words, play it as beeps or flashes of light, and practise sending it.
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Hold the key down for a dash, tap it for a dot. Pause for a letter; pause longer for a new word. It reads back what you sent at the speed set below (start slow).
Listening and watching live only work on a secure (https) page, so on the Vault's own Wi-Fi record a video instead: the phone's camera records the sound too. On the website, live works.
The whole code (tap one to hear it)
Signals sent as one run, with no gaps
Good to know
The timing is the code: a dash lasts three dots. Leave one dot of silence inside a letter, three between letters and seven between words.
SOS is sent as one unbroken run, ...---..., over and over. Any signal sent three times (three flashes, three blasts) also means help.
Reading a signal works best with a steady beep (a radio's Morse tone, a whistle, a horn) in a quiet place, or a clear light in the dark, at up to about 15 words a minute. A few words sent at an even pace read best; set the speed above to roughly match a very short message.
At night, 💡 Flash the screen turns the whole phone into a signal lamp: turn the brightness all the way up and point it.
More, with pictures: the Signals & Morse guide (how to learn it by ear, and sending it by light, sound and flags).