RC25 disk drive

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RC25
Manufacturer: DEC
Drive Controller(s): KLESI Low-End Storage Interconnect‎
Capacity: 26 Mbytes (fixed)
26 Mbytes (removeable)
Transfer Rate: 1.25 Mbytes/sec
Average Access Time: 30.5-45.5 msec
Revolutions per Minute: 2850
1/2 Revolution Time: 10.5 msec
Average Seek Time: 20-35 msec
Maximum Seek Time: 55 msec
Media: 1 fixed
1 removeable
Total Surfaces: 4 (2 fixed, 2 removeable)
Number of Heads: 4
Tracks per Surface: 821
Sectors per Track: 31
Bytes per Sector: 512
Tracks per Inch: 1,000
Density: 12,350 bits/inch
Start Time: 60 secs (max)
Stop Time: 30 secs (max)
Physical Size: 10.4" x 19.9" x 22.1"
Weight: 65 lbs (single drive)
Power Consumption: 300 watts (idle)


The RC25 disk drive was a combination non-removable-media disk and removable-pack disk (using a sealed pack) on a singled spindle, from DEC. Each 8" platter had a capacity of 26 MB, for a total of 52 MB. It connected to the device controller via the DEC standard Low End System Interconnect bus; a second 'slave' drive can be connected to the first 'master' drive. It uses the Mass Storage Control Protocol, and is member of the Digital Storage Architecture.

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