Check out these téléphone mobile images:
Image by Monster.
I understand that these are soon to be removed, the curse of the mobile phone continues.
Radio Electronics Nov 1948
Image by Whiskeygonebad
This is a the "Mobile Phone" commercial use concept that existed in 1948. Motorola among many were in a battle for miniaturization, yet they were all still stuck in the pre-transistor tube/valve age. The dawn of a new era was at hand. Bell Labs, now know as Lucent Technologies, developed a promising three-terminal device constructed on a substrate of germanium along with other trace metals. It showed gain using very low voltages as compared to tubes. This two-way radio depicted above has a microphone/speaker shaped like a telephone handset. It is not full duplex: You have on the handset handle a PTT [Push To Talk} button bar to press in when you want to speak and to release to listen. Motorola recently tried to legally keep anyone from commercially using the term PTT that they use on their annoying cell "walkie-talkie feature" phones. They lost. BTW: Half of that box is full of Batteries. An "A Battery ", [4 to 12v] just for the tube heaters, and a "B Battery", for the actual working circuitry [likely 90v – 2x45v Batteries in series or as 1 unit].
Chances are that you now have not millions, but billions of transistors devices in your home and they ain’t leaving.
Say Hello to the Transistor 1948.