Ed Roberts (computer Engineer) - Calculators

Calculators

Ed Roberts's first real experience with computers came while at Oklahoma State University where engineering students had free access to an IBM 1620 computer. His office at the Weapons Laboratory had the state of the art Hewlett-Packard 9100A programmable calculator in 1968. Roberts had always wanted to build a digital computer and in July 1970, Electronic Arrays announced a set of six LSI integrated circuits that would make a four-function calculator. Roberts was determined to design a calculator kit and got fellow Weapons Laboratory officers, William Yates and Ed Laughlin, to invest in the project with time and money.

The first product was a "four-function" calculator; it could add, subtract, multiply and divide. The display was only 8 digits, but the calculations were performed with 16 digits of accuracy. The MITS Model 816 calculator kit was featured on the November 1971 cover of Popular Electronics. The kit sold for $179 and an assembled unit was $275. Unlike the previous kits MITS had offered, thousands of calculator orders came in each month.

The monthly sales reached $100,000 in March 1973 and MITS moved to a larger building with 10,000 square feet (930 square meters) of space. In 1973 MITS was selling every calculator they could make, 110 employees worked in two shifts assembling calculators. The functionality of calculator integrated circuits increased at a rapid pace and Roberts was designing and producing new models. The popularity of electronic calculators drew the traditional office equipment companies and the semiconductor companies into the market. In September 1972, Texas Instruments (TI) introduced the TI-2500 portable four-function calculator that sold for $120. The larger companies could sell below cost to win market share. By early 1974, Ed Roberts found he could purchase a calculator in a retail store for less than his cost of materials. MITS was now $300,000 in debt, and Roberts was looking for a new hit product.