【Mitsubishi Electric】 M-834 Disk Pack Unit

This was Mitsubishi Electric's first removable disk pack drive, announced in 1969. It had complete compatibility with the IBM-2311 and CDC9463. The M-834 was used with the MELCOM 3100 and MELCOM 9100.

This unit had the following features.

  • The positioning mechanism was electric, so handling was simple.
  • It employed integrated circuits for high reliability.
  • The unit was independent because the power supply was built-in.
  • Self-diagnosis functions were built-in, so malfunctions could be discovered quickly.
Main Specifications of M-834 Disk Pack Unit
Memory capacity 7,250KB
Track capacity 3,625byte
Number of tracks 200+3 spare tracks
Memory Disk sides 10side/pack
Disk rotation speed 2,400rpm
Data transfer speed 156Kbyte/s
Positioning time Max. 135ms,Min. 24ms
Bit density 44bit/mm(Max.)
Track density 4track/mm
External dimensions(Width×Depth×Height) 610mm×920mm×1,050mm
Weight 250kg

M-834 Disk Pack Unit