Mastodawn

@tiefpunkt
MMDVM Hotspot hat for a Raspberry Pi is what we mainly use in the ham world for this kind of situation

You would need a board that could support duplex

You would have to set-up a private host so that it doesn't connect to any ham networks

Private channels are a thing so no need to worry about that

Pistar or WSPD is the os for the Pi

Getting pmr to work would need analog FM mode but with a bit of effort this could be achieved