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    • Apr 3, 2023
    • 2 min read

The 'Brick' that Changed the World

Updated: Jul 21, 2023

#54 Science in History

3rd April 1973


On April 3rd, 1973, Martin "Marty" Cooper made the first-ever cellular phone call.

Cooper, who was an engineer and executive at Motorola, placed the call on a prototype of what would become the first handheld cellular phone, the Motorola DynaTAC. Cooper called his rival, Joel Engel, who was head of research at Bell Labs, the research arm of AT&T, which at the time was the largest telephone company in the United States. Cooper famously said to Engel, "I'm calling you from a cellular phone, but a real cellular phone. A handheld, portable, real cellular phone." The call lasted for about 20 minutes and marked a major milestone in the development of mobile communication technology.


The phone that Martin Cooper used was a prototype of what would become the Motorola DynaTAC. The prototype was a large, brick-shaped device that weighed around 2.5 pounds (1.1 kg) and measured 9 inches (23 cm) in length. It had a talk time of only 35 minutes and took around 10 hours to charge.

A Motorola DynaTAC 8000X from 1984

The final version of the DynaTAC, which was released 10 years later in 1983 (1985 in the UK), was smaller and more portable than the prototype. It measured around 10 inches (25 cm) in length and weighed 28 ounces (794 grams). The DynaTAC had a talk time of around 1 hour and took around 10 hours to charge. You could store up to 30 phone numbers and it also had a dedicated redial button. The analogue phone and operated on the Advanced Mobile Phone System (AMPS) network, which was the first commercial cellular network in the United States. It had a maximum power output of 600 milliwatts and a range of around 10 miles (16 km) from a cell tower. The phone had a numeric keypad and a monochrome LCD screen that displayed call information and battery life.


‘The Brick’, as it became known, was costly at £3000* (nearly £7000 in today’s money) and was initially marketed to wealthy businesspeople, celebrities, and government officials, rather than to the public. Even so, it generated a lot of excitement and interest among consumers - waiting lists quickly formed. Some reports suggest that the waiting list for the DynaTAC was as long as six months, with customers putting down deposits to reserve their phones.


Despite the high cost and limited availability, the DynaTAC was a commercial success, paving the way for the development of more affordable, widely available cellular phones in the years that followed.



*If you visited the electrical retailer ‘Currys’ back in 1985, you could buy a fridge-freezer, washing machine and microwave oven for just over £600!





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