The Calculator That Helped Land Men on the Moon

Olivetti’s Programma 101 embodied the company’s holistic approach to technical efficiency, ease of use, and smart design

3 min read
Italy’s Olivetti Programma 101.
Photo: Elisabetta Mori

After the sale of its computer business to General Electric in 1964, Italy's Olivetti managed to retain control of its small electronic calculators. The most notable of these would be the Programma 101.

Introduced at a Business Equipment Manufacturers Association show in New York in October 1965, this programmable desktop calculator proved an immediate success. Also known as the P101 or the Perottina (after the chief engineer who designed it, Pier Giorgio Perotto), it eventually sold more than 40,000 units, primarily in the United States but also in Europe. NASA bought a number of P101s, which were used by engineers working on the 1969 Apollo 11 moon landing.

Chief among the machine's selling points was its portability. Roughly the size of an electric typewriter, it could be used in program mode like a computer, with stored instructions, while in manual mode it served as a high-speed calculator. Its memory consisted of a magnetostrictive delay line, which used pulses of sound traveling along a coil of nickel alloy wire to store numeric data and program instructions. This kind of memory was used in several other small computers and calculators, including the Ferranti Sirius, a small business computer, and the Friden EC-130 and EC-132 desktop calculators.

The P101 had a 36-character keyboard, a built-in mechanical printer, and a magnetic card reader/recorder, for storing and retrieving programs. Olivetti supplied a library of commonly used programs. There was no display as such.

The P101 used only high-level instructions, so programming it was extremely simple. As a promotional video proclaimed, “A good secretary can learn to operate it in a matter of days!" The ad showed the P101 being used in a research lab, beside a swimming pool, and even at a betting hall.

At a time when bulky mainframe computers required a team of programmers, engineers, and operators to run, the P101's compact size, capabilities, and ease of use were remarkable. Like all computers of that era, it wasn't exactly cheap: The P101 could be leased on a monthly basis, or bought outright for US $3,200 (about $25,000 today). For comparison's sake, the monthly rent on an IBM System/360 mainframe ranged from $2,700 to $115,000, with purchase prices from $133,000 to $5.5 million.

The calculator's technical features inspired imitation: Hewlett-Packard reportedly paid Olivetti approximately $900,000 in royalties because of the similarities between the architecture and the magnetic cards of the HP 9100 programmable calculator series and those of the Programma 101.

Photo of the engineering team that developed Olivetti's Programma 101 desktop calculator.Pier Giorgio Perotto (seated, left) led the engineering team that developed Olivetti's Programma 101 desktop calculator. His team also included (clockwise from top left) Gastone Garziera, Giancarlo Toppi, and Giovanni De Sandre.Photo: The Picture Art Collection/Alamy

The P101's aesthetic and ergonomic design was the work of a talented young Italian architect named Mario Bellini. In contrast to Ettore Sottsass Jr.'s futuristic look for Olivetti's ELEA 9003 mainframe, Bellini's P101 is curvy and sensual while still being user friendly. Its rounded edges comfortably supported the user's wrists and hands. Magnetic cards could be easily inserted into the central slot. On the right-hand side, a green/red light added a touch of color while also alerting the user to any malfunctions. The Programma 101 is now part of the permanent collection at the Museum of Modern Art in New York City.

If you own a Programma 101 and need to get it fixed, don't despair. A team that includes some of the P101's original designers, former Olivetti engineers, and volunteers will help you restore and repair it. Their lab is located in the Museo Tecnologicamente in Ivrea, the town near Turin where Olivetti was founded.

For more on Olivetti's pioneering computers, see “The Italian Computer: Olivetti's ELEA 9003 Was a Study in Elegant, Ergonomic Design."

For more about Mori's close encounter with an ELEA 9003 computer, see “The Last Working Olivetti Mainframe Sits In a Tuscan High School."

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