I'm not sure if deprecated is the right word. When the zombie invasion comes, I do not feel confident in my ability to get the cellular network back up running.

I'm not sure if deprecated is the right word. When the zombie invasion comes, I do not feel confident in my ability to get the cellular network back up running. I could easily build a spark gap transmitter though, using spare parts that can be found anywhere and high-school level electrical engineering. In seriousness, it seems somehow foolish to deprecate an extremely reliable, cheap and time-tested form of communication. That said, I never got far in my own attempts to learn Morse code :-)