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IBM 2401 magnetic tape unit

IBM 2401 Magnetic Tape Unit

IBM 2401 Magnetic Tape Unit

Models 1, 2 and 3

Each of these models, specifically designed for use on the IBM System/360, used a nine-track read/write head and had a single density of 800 bytes per inch. Any of these models could be attached to IBM System/360 through the 2803 or 2804 Tape Control.

Model 1 Model 2 Model 3
Data rate (8 bit bytes per second) 30KB/
60KD
60KB/
120KD
90KB/
180KD
Tape Speed (inches per second) 37.5 75.0 112.5
Nominal IRG Time (milliseconds) 16.0 8.0 5.3
Rewind Time (minutes) 3.0 1.4 1.0
Rewind and Unload (minutes) 2.2 1.5 1.1

Models 4, 5 and 6

Also specifically designed for use on the IBM System/360, these models of the 2401 used a nine-track read/write head and recorded data at 1600 bytes per inch. They could be attached to IBM System/360 through the IBM 2803/2804 Tape Control, Model 2.

Model 4 Model 5 Model 6
Data rate (8 bit bytes per second) 60KB/
120KD
120KB/
240KD
180KB/
360KD
Tape Speed (inches per second) 37.5 75.0 112.5
Nominal IRG Time (milliseconds) 16.0 8.0 5.3
Rewind Time (minutes) 3.0 1.4 1.0
Rewind and Unload (minutes) 2.2 1.5 1.1

Initial shipments of the improved 2401s from IBM's Boulder, Colo., manufacturing facility began in August 1966, one year after they were announced. More than 30,000 of these tape drives were installed within the first four years of their availability.