Happy Anniversary to the World's First Cell-Phone Call

43 years ago today, on April 3, 1973, a Motorola engineer named Martin Cooper made the first cell phone call. At the other end of the line from his 2.5 pound Motorola Dyna-Tac prototype was Cooper's chief rival, Joel S Engel, the head of Bell Labs. "Joel, this is Marty," Cooper said, according to a 2013 interview with the BBC. "I'm calling you from a cell phone, a real handheld portable cell phone."

"Portable" is relative, of course. The Dyna-Tac was as big as it was heavy: 9 x 5 x 1.75 inches. Packed inside of this shoebox were 30 circuit boards and a battery with about a half-hour of talk time that required 10 hours of recharging. It had no display, and offered only three features: talk, listen, dial. It was, in a word, dumb.

But it worked. The Dyna-Tac had by then already gone through some FCC testing in Washington, DC, and, on the big day, Cooper was to demonstrate the phone to a press conference at the Manhattan Hilton. Motorola was at the time trying to convince the FCC to allocate more frequency bandwidth to companies trying to commercialize the nascent technology. Hence, the PR push.

Before heading upstairs to the conference, Cooper decided that he'd better make sure the damn thing worked first. "He picked up the two-pound Motorola handset called the Dyna-Tac and pushed the 'off hook' button," a 2000 New York Times interview with Cooper recalls. "The phone came alive, connecting Mr. Cooper with the base station on the roof of the Burlington Consolidated Tower (now the Alliance Capital Building) and into the land-line system. To the bewilderment of some passers-by, he dialed the number and held the phone to his ear."

By that time, the primitive idea of mobile telephone communications was actually quite old. AT&T had first commercialized a variation in the 1940s called Mobile Telephone Service, which was based on VHF radio communications, the range of frequencies more commonly employed for two-way radio use and television and radio broadcasts. Only a small slice of VHF channels were available to the service and collisions between transmissions were a common and prohibitive occurrence.

MTS was essentially a form of two-way radio communication with an operator in the middle that bridged landline callers with mobile callers. A "call" would be announced not by a ring, but by the voice of an operator over the radio saying that they had a call for that specific user. Every user would hear every incoming call and the idea was that they just ignored the ones that weren't for them.

The hardware required for MTS also weighed about 80 pounds.

Real portability would have to wait for the advent of cellular communications. Here, users can be passed between base stations and frequencies can be continually reused. In addition to truly portable hardware, this means that users can reasonably move around from place to place with some guarantee of service.

In the 2000 Times interview, Cooper offered a prediction: "Cellular was the forerunner to true wireless communications. And just as people got used to taking phones with them everywhere, the way people use the Internet is ultimately going to be wireless. With our technology, you will be able to open your notebook anywhere and log on to the Internet at a very high speed with relatively low cost. At the moment, our story is about what a relatively small company is doing with high-tech stuff in Silicon Valley."

''But when people get used to logging on anywhere," he added, "well, that's going to be a revolution.''