Re: ...or after an electromagnetic pulse event.
An EMP pulse isn't magic. It will be unpredictable, but probably won't kill most small electronics. Especially small devices inside a big tin can that aren't attached to anything (e.g. a charger) when it happens.
It's hard to foresee the communications speed needed after such an event, but I doubt that there is much of a difference between the 4-5 WPM possible by manual transcription and double that with an experienced operator (I'm don't expect a signal light will support 20WPM.. not that anyone will be sending a lengthy missive.)