As I noted last week, the term “wireless telephone” in the early 1920s didn’t necessarily mean a device that could both transmit and receive messages. In fact, most radio devices during this time were simply either a transmitter or a receiver. However, some inventors were having a lot of fun tinkering with what was essentially walkie-talkie technology, in that they were developing transceivers — devices that could both transmit and receive radio messages. An article in the March 21, 1920 Sandusky Register in Sandusky, Ohio retold the story of a man in Philadelphia named W. W. Macfarlane who was experimenting with his own “wireless telephone.” With a chauffeur driving him as he sat in the back seat of his moving car he amazed a reporter from The Electrical Experimenter magazine by talking to Mrs. Macfarlane, who sat in their garage 500 yards down the road.



More: http://blogs.smithsonianmag.com/paleofuture/2012/01/the-worlds-first-carphone