Great find from BoingBoing. There is something about these old time info videos, you can tell they really put some work into them. A very early video from Bell teaching how their mobile phone works. I think the best part of the video is when they explain the use of a mobile phone!
MTS was a pre-cellular VHF radio system that linked to the Public Switched Telephone Network (PSTN). As such it used both radio signals and telephone lines to connect parties. MTS was the radiotelephone equivalent of land dial phone service. The Mobile Telephone Service was one of the earliest mobile telephone standards. It was operator assisted in both directions, meaning that if one were called from a land line the call would be routed to a mobile operator, who would route it to one’s phone. Similarly, to make an outbound call one had to go through the mobile operator, who would ask for the mobile number and the number to be called, and would then place the call.
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