I wonder if ship speaking tubes/voicepipes might be improved.
There even used to be C.B. telephones that used two channels.
https://www.radiomuseum.org/r/johnson_vi_messenger_130_242_0130.html
The Johnson Messenger 130a was such an example...then came car-phones that used a city based transmitter before smaller, more numerous cells were added.
There even used to be C.B. telephones that used two channels.
https://www.radiomuseum.org/r/johnson_vi_messenger_130_242_0130.html
The Johnson Messenger 130a was such an example...then came car-phones that used a city based transmitter before smaller, more numerous cells were added.
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