Calculator This led the way to the first credit-card-sized calculators, such as the Casio "Mini Card LC-78" of 1978, which could run for months of normal use on button cells. There were also improvements to the electronics inside the calculators. All of the logic functions of a calculator had been squeezed into the first "calculator on a chip" integrated circuits (ICs) in 1971, but this was leading edge technology of the time and yields were low and costs were high. Many calculators continued to use two or more ICs, especially the scientific and the programmable ones, into the late 1970s. The
Koyo Electronics Corporation Limited Koyo Electronics Corporation Limited Koyo Electronics (Kōyō Denki) and its subsidiary Koyo Electronics Industry (Kōyō Denshi Kōgyō), often collectively referred to as just Koyo, are Japanese electronics companies based in Kodaira, Tokyo that manufactured radios since 1955 until 1973, and now its subsidiary manufactures industrial electronics devices and factory automation control systems. Their first product was a vacuum tube radio released in 1955, and their first transistor radio was the KR-6TS-1 radio released in the spring of 1957 at the price of 14,000 yen. Through the 1960s, Koyo had manufactured and sold millions of portable transistor radios, particularly, their best-selling