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IBM 603

The First Commercial Electronic Calculator

The IBM 603 brought the speed and power of electronic computation to business, laying groundwork for an entire industry, and proving that the future of technology lay in electronic devices.

As early as 1936, IBMer A. Halsey Dickinson was researching computation that used vacuum tubes. He would later invent the first method to perform electronic addition and subtraction. Vacuum tubes held great promise for researchers because they could be quickly switched on or off in a circuit called a “flip-flop.” That meant the tubes could represent the binary counters that were growing in favor in the scientific community.

The University of Pennsylvania used this technology to create the Electronic Numerical Integrator And Computer (ENIAC) for the US Army. The ENIAC contained 17,480 vacuum tubes and was used for atomic research. Byron Phelps, who would later serve as the lone engineer on the electronic multiplier prototype of the IBM 603, designed the decimal counting wheel for the ENIAC.

The counting wheel in the ENIAC used 10 vacuum tubes per number—far too many for a commercial product. Phelps cut this number in half by inventing binary-coded decimal representation, a way of using five tubes to represent 10. Fewer vacuum tubes meant smaller, faster, less expensive electronic devices.

It also meant more reliable computers. At that point, vacuum tubes were prone to intermittent failure. If one of the tubes failed, the machine provided skewed results. With 17,468 tubes pulsing 100,000 times a second in the ENIAC, there were 1.8 billion chances of a tube failure every second. Reducing the number of tubes reduced the chances for error.

By December 1942, Phelps and C.A. Bergfors had built a prototype electronic calculator in an attic at the Endicott Engineering Laboratory. The IBM 603, modeled after this prototype, was released in 1946.

IBM quickly followed the 603 with the 604, which boasted a number of technological innovations. Its construction was modular, featuring “pluggable units.” This meant each tube could be tested prior to its installation, speeding the manufacturing process and simplifying servicing of the machines. Malfunctioning machines could be quickly diagnosed and repaired.

The 604 also switched from radio tubes to miniature tubes. To minimize intermittent tube failure, Ralph Palmer founded an IBM vacuum tube research facility on the bank of the Hudson River. Affectionately known as the “pickle factory” because it was purchased from vegetable and jam merchants R. U. Delapenha & Co., the facility was where IBM created cleanliness and quality control standards for the production of digital devices that were adopted across the industry. The facility is also where IBMer Jerrier Haddad designed a 6J6 replacement tube that General Electric put into production.

Technical specs of a vacuum tube

Innovations at the pickle factory

IBMers at the pickle factory developed clean room practices now standard for producing digital technology. It was also where Jerrier Haddad designed a 6J6 replacement tube that General Electric, concerned that IBM might begin manufacturing tubes of their own, quickly put into production.