Prototype of the world’s first handheld electronic calculator, the CAL-TECH
Photo: Smithsonian Libraries

Jerry Merryman, one of three people at Texas Instruments credited with inventing the world’s first handheld electronic calculator in the 1960s, died at a Dallas hospital on February 27. Merryman was 86 years old.

In the fall of 1965, Merryman and his coworkers at TI were tasked with creating a handheld electronic calculator in an era when most electronics, from computers to calculators to televisions, were enormous machines. The smallest calculator at the time weighed over 45 pounds. Eighteen months later, in 1967, Merryman helped deliver a 3-pound prototype to his boss. It was dubbed the CAL-TECH and that prototype now sits in the Smithsonian.


As the Associated Press notes, the team was led by Jack Kilby who invented the integrated circuit in 1958 and would go on to win the Nobel Prize in Physics in the year 2000. There were plenty of people who thought it couldn’t be done, but Merryman, along with his colleagues like James Van Tassel at TI, worked night and day on the project.

“[Kilby] called some engineers in his office and said we need to make some sort of personal computing device. It would have to have some buttons on it to put in a problem, and some neon lights or something to give the answer,” Merryman told the Associated Press in a video interview from 2007. “It would have to be battery-operated and small enough to hold in your hand.”

One of the biggest problems wasn’t simply making the calculator relatively small, it was doing so without breaking the bank. As Merryman told the AP, some at TI were convinced that you could make the thing without spending thousands of dollars on parts alone.

The prototype could do four basic functions: addition, subtraction, multiplication, and division. And while the calculator is incredibly primitive to those of us in the 21st century, it revolutionized the world of electronics. The term “calculator” hadn’t caught on yet, so the first generic name for the thing internally at TI was a “slide rule computer.” A commercial version of the calculator, branded as the Pocketronic, went on sale in 1970.


As the 1996 paper “The History of the Hand-Held Electronic Calculator,” by Kathy B. Hamrick explains, TI wanted to make a handheld calculator because at the time, the company’s microchips were only being used by the military and industry. TI’s chips were powering the Cold War’s Minute Man missiles that stood ready in the event of nuclear war, but the tech company wanted to break into the consumer market to create a demand for its chips.

When the Pocketronic calculator hit the market, popular media didn’t mention Merryman or anyone else on the Texas Instruments team by name. It was important work in the field of consumer electronics, but like so many inventions of the 20th century done at labs and big companies, it was largely anonymous labor.

The handheld calculator received plenty of 40th birthday celebrations in 2007 though, and the introduction of the CAL-TECH prototype into the Smithsonian was rewarding for Merryman nonetheless.


“The most overwhelming thing was seeing my prototype between the work of Tom Edison and Graham Bell at the Smithsonian,” Merryman said at a ceremony in 2007.

“He always said that he didn’t care anything about being famous, if his friends thought he did a good job, he was happy,” Phyllis Merryman, Jerry’s wife, told the AP. 

[Associated Press]