When we think of the first mobile phones, it may conjure images of the brick telephone used by 90s icon Zack Morris from Saved by the Bell. But recently, an advertisement for a Mobile Telephone Service (MTS) from the 1940s was found by Open Culture.

The movie explains the multiple benefits of being able to communicate while on the road, conducting business, and in case of car trouble. It also shows how some of the cutting-edge equipment at the time was used and installed in vehicles.

“This is mobile telephone service. In this service conversations travel part way by radio part way by telephone lines,” the announcer explains.

Initially, the system had only 3 channels with more licenses added, bringing the total to 32 channels across 3 bands. According to the video, “In order to reach vehicles traveling the highways between cities, a number of transmitting and receiving stations connected to telephone lines are spaced at intervals along the highway so that one will always be in range of the moving vehicle. The antennas are placed preferably on high ground because the high frequency waves are limited in distance to the line of sight.”

MTS was operated by Bell Telephone Company and its first call was made from St. Louis on June 17, 1946, from a Motorola Car Radiotelephone. The system was replaced in the 1980s by cellular service. But for a time, we lived in the convenient future of mobile phone calls connected manually by a live operator.