LARGE CAPACITY MAGNETIC DRUM STORAGE SYSTEM.

This paper describes the design and test results of a large capacity magnetic drum storage system developed for the DIPS-11 system. It has a 15 MB storage capacity, a 5. 3 ms average access time and a 1. 45 MB/s data transfer rate. Linear and track density are 156 bits/mm and 3 tracks/mm, respectively. For achieving higher recording density and higher transfer rate, flying head spacing and magnetic film thickness were decreased. A new modulation method and a new signal sensing method are employed. The performance of the drum controller was also improved by employing a variable length record format, multiple requesting function and logical device concept.