Hitachi HIPAC 101

This was a parametron-based computer, developed by enhancing the HIPAC MK-1 for display at a computer exhibition sponsored by UNESCO and held in Paris in June 1959. The main improvements included: use of eyeglass-type parametrons as the logic element, and conversion of the magnetic drum control circuits from vacuum tubes to transistors. Overall, the system was smaller than the HIPAC MK-1, and reliability was also markedly improved.