Peripheral Equipment:Magnetic Drum Units

Brief HistoryExhibits

year/month Timeline
【World】Gustav Tauschek invented magnetic drum memory
【World】IBM used magnetic drum memory in the IBM 650
1956  Electrotechnical Laboratory developed Japan’s first magnetic drum unit, which was used as the main memory for the ETL Mark IV.
1958  Fujitsu completed the D101 magnetic drum unit, the company’s first computer-system-use model.
1958  Hokushin Electric (later Yokogawa Hokushin Electric and currently Yokogawa Electric) developed a magnetic drum unit as the main memory for electronic computers.
1959  Hokushin Electric (later Yokogawa Hokushin Electric and currently Yokogawa Electric) developed the MD 1001A magnetic drum unit as auxiliary memory for electronic computers.
1960  Fujitsu completed the FACOM 621 magnetic drum unit to serve as the auxiliary memory unit for the FACOM 222 System.
1961/04 NEC completed the IR-807 and IR-809 magnetic drum units for use as internal memory in the NEAC-2205 and NEAC-1201.
1962/11 NEC completed the 523 magnetic drum unit and used it in the NEAC-2206 and NEAC-2230.
1964/05 Oki Electric completed the Model G Series magnetic drum unit.
1966/04 NEC announced the N271A magnetic drum unit of FM recording type with floating magnetic heads and plated recording media.
1968/09 Hitachi completed the H-8566 magnetic drum unit, which used the floating head method and boasted the highest performance of any Japanese made unit.
1968  Fujitsu completed the FACOM 624 high-capacity, high-performance drum unit that utilized the floating head method.
1969/08 Hitachi completed the H-8567 magnetic drum unit that achieved four times smaller volume and two times higher capacity.
1969  Fujitsu completed the FACOM 628K magnetic drum unit for use at the system drum in the midsize general-purpose computer FACOM 230-25/35.
1970  NTT completed the Model No.1 Magnetic Drum Unit (4 MB unit capacity).
1971  Fujitsu completed the FACOM 6621 magnetic drum unit using a 4-bit parallel data transmission method to achieve high-speed data transmission.
1975/07 Hitachi completed the H-8575 magnetic drum unit that achieved high speed with twice rpm and also achieved four times higher capacity.
1975  NTT completed the Model 301 magnetic drum unit (Model JS4160), which had world-class performance.