The Random-Access Memory Accounting Machine—II. The Magnetic-Disk, Random-Access Memory

Abstract

The design features are described of a new large-capacity memory device having random access to information stored magnetically on rotating disks. The mechanical arrangement of an array of 50 disks is shown, and details are given of the pair of magnetic recording heads, which are spaced accurately from the disk surface by air jets. The access mechanism and the timing system for positioning the heads on the disk tracks are described. The total storage capacity of the system is 5,000,000 alphanumeric characters.