First Handheld Mobile Phone Call (1973): Martin Cooper

The first public call on a handheld mobile phone was made on 3 April 1973 by Martin Cooper of Motorola, standing on Sixth Avenue in Manhattan. Using a prototype the size of a brick, he phoned a rival engineer at AT&T’s Bell Labs. The demonstration showed that a cellular telephone could belong to a person rather than a car, a decade before such phones went on sale.

Background: car phones and the cellular idea

Mobile telephones existed long before 1973, but they were bulky radios installed in cars. The first US mobile telephone service opened in St. Louis in 1946. Each city had only a few channels, so very few people could use the service at once and waiting lists were long.

In 1947 Bell Labs engineers Douglas Ring and W. Rae Young described a better approach: divide a city into small areas, or “cells”, each served by a low-power transmitter, so the same radio frequencies could be reused in different cells. As a user moved, the call would be handed from one cell to the next. The idea needed more radio spectrum, faster switching and smaller electronics, and for two decades it remained mostly on paper.

By the late 1960s AT&T, the giant US telephone monopoly, was asking the Federal Communications Commission (FCC) for spectrum to build a cellular system. Its plans focused on car phones. Motorola, the leading maker of two-way radios for police and businesses, feared that AT&T would dominate the new market and argued that people, not cars, needed to be mobile.

Building the DynaTAC prototype

Martin Cooper had worked at Motorola since 1954 and led its work on portable communications. In late 1972, with the FCC weighing its decision, Motorola executive John F. Mitchell backed a crash programme to build a working handheld cellular phone that could be shown to regulators and the public.

Industrial designer Rudy Krolopp’s team produced the casing, and engineers squeezed radio, control and battery circuits into it in about three months. The phone, called the DynaTAC (Dynamic Adaptive Total Area Coverage), weighed about 1.1 kilograms and was about 23 centimetres tall without its antenna. It had a numeric keypad and a battery that allowed about 20 to 30 minutes of talk before needing roughly 10 hours to recharge.

To make a call possible, Motorola set up a base station on a building in midtown Manhattan, connected to the ordinary telephone network.

The call on Sixth Avenue

On 3 April 1973, before a press conference at the New York Hilton, Cooper stood on Sixth Avenue with the prototype. He looked up the number of Joel Engel, head of the Bell Labs cellular effort, and called him directly.

Cooper’s account is that he told Engel he was calling from a real, handheld, portable cellular phone, and that the line went quiet. Engel later said he did not remember the call. Either way, the point was made publicly: Motorola had a working personal cellular phone, and AT&T did not.

Cooper and his colleagues then demonstrated the phone to reporters at the press conference. The event was meant as much for regulators in Washington as for the public: it showed that a personal cellular service was technically possible.

From prototype to product

The prototype was a demonstration, not a product. Building a working cellular network required FCC approval of spectrum, standards, switching systems and many base stations. The FCC spent years on the question, and AT&T and Motorola continued to compete over how the market should be organised.

Other countries moved first. Japan’s NTT opened a cellular car-phone network in Tokyo in 1979, and the Nordic Mobile Telephone system began in Scandinavia in 1981. In the United States, the first commercial cellular network opened in Chicago on 13 October 1983, using a standard known as AMPS.

The years between 1973 and 1983 were spent on the less visible work. Motorola and AT&T both ran trial systems, with AT&T’s test network in Chicago beginning service to trial customers in the late 1970s. The FCC finally set aside spectrum for cellular service in the early 1980s and decided that each market would have two licensed carriers, one of them a local telephone company. Engineers also had to shrink the electronics: early phones relied on many separate chips, and only steady advances in integrated circuits made a practical handset possible.

Motorola’s commercial handheld phone, the DynaTAC 8000X, received FCC approval in September 1983 and went on sale in 1984 for 3,995 US dollars, a high price that limited it to business users. It weighed about 0.8 kilograms and offered about 30 minutes of talk time.

Key people

Martin Cooper is usually called the father of the handheld mobile phone, a title he has accepted while stressing that the work was a team effort. John F. Mitchell, who led Motorola’s communications business, pushed for the project and is credited by many historians as its champion.

At Bell Labs, Joel Engel and Richard Frenkiel led much of the engineering of the cellular system itself, including how calls were handed between cells. In 2013 Cooper, Engel and Frenkiel were among five engineers awarded the Charles Stark Draper Prize of the US National Academy of Engineering for their contributions to cellular telephony.

Myths and facts

Cooper’s call is sometimes described as the first mobile phone call ever. It was not: radio telephones had carried calls from cars since the 1940s, and engineers in several countries, including the Soviet Union, built experimental portable radio telephones in the 1950s and 1960s. Cooper’s call is significant as the first public call on a handheld phone designed for a cellular network.

Another common belief is that the 1973 phone was the one later sold to the public. The DynaTAC 8000X of 1983 was a new, lighter design built on ten years of further development. The 1973 prototype could make calls only within range of Motorola’s single demonstration base station, not across a city-wide network.

Legacy

The brick-sized DynaTAC became an icon of the 1980s. Phones shrank rapidly in the 1990s as digital networks such as GSM spread from Europe across the world, and text messaging and mobile data followed.

Later devices such as the iPhone turned the mobile phone into a pocket computer. By the 2020s there were more mobile subscriptions in the world than people, a shift that began with a telephone call made on a New York street, more than a century after the telephone patent of 1876.

Timeline

• 1946: The first US mobile telephone service for cars opens in St. Louis.
• 1947: Bell Labs engineers describe the cellular concept.
• 1972, late: Motorola begins a crash programme to build a handheld cellular phone.
• 1973, 3 April: Martin Cooper makes the first public handheld cellular call in New York.
• 1979: NTT opens a cellular car-phone network in Tokyo.
• 1983, September: The FCC approves the Motorola DynaTAC 8000X.
• 1983, 13 October: The first US commercial cellular network opens in Chicago.
• 1984: The DynaTAC 8000X goes on sale for 3,995 US dollars.

Why it matters

Cooper’s call made the case that a telephone number could belong to a person instead of a place. That idea reshaped communication, work, travel and daily life in almost every country in the world.