HITAC 5020

This was the first large general-purpose computer, domestically-developed in Japan. It was designed and manufactured primarily for calculations relating to science/engineering or scientific management, but it was also appropriate for business calculations. It was a second-generation computer which used transistors, and was developed by Hitachi's own technology. Its performance was equivalent to that of American computers which were dominant at that time, and it marked a new age of the Japan’s domestic computers.

In April 1960, Kenro Murata and Kisaburo Nakazawa -- the leading designers of TAC, the University of Tokyo's vacuum tube based computer -- joined Hitachi Ltd., and development of the HITAC 5020 began. Design began in 1961, and the first prototype was completed in May 1963. After that, the design and prototyping of channels were done, and in 1964, a prototype of the entire system was finished. In 1965 the #1 machine was delivered to Kyoto University.

The following are the related components which are preserved:

• Core memory stack
• Core memory stack plane
• Flip-flop with a delay line
• Flip-flop
• Sense-up circuit for memory
• Delay line register