From the “everyone needs a hobby” department, we found this ultra-detailed miniature of an IBM 1401 mainframe system to be completely enthralling. We may have written this up at an earlier ...

His latest installment is an article describing the strange implementation of the IBM 1401’s qui-binary arithmetic. Full disclosure: It has not been confirmed that [Ken] is an “old-timer ...

IBM's second successful commercial computer (the first was the 650). Introduced in 1959 and offered until 1971, the 1401 was an outstanding success. More than 12,000 systems were installed ...