User's Manual

Specifications
11
The following table lists the specifications for the DDS-4 drive.
Specification
Value
Capacity (with 2:1 compression)
90 m MP
120 m MP+
125 m MP++
150 m MP+++
4.0 Gbytes
8.0 Gbytes
24.0 Gbytes
40.0 Gbytes
Track density (DDS)
147.34 tracks per mm
Error recovery
Read-after-write
Reed Solomon ECC (C3 - 3 levels)
Recording unrecoverable errors
< 1 in 10
15
data bits
Tape drive type
Computer grade 4DD mechanism
Head configuration
2 read heads, 2 write heads
Recording format
DDS-4
Recording method
Helical scan (R-DAT)
Cartridge
73.66 mm × 53.34 mm × 10.16 mm
Transfer rate (sustained)
5.500 Kbytes per sec (DC ON)
Synchronous transfer rate (burst)
80 Mbytes per sec max
Asynchronous transfer rate (burst)
10 Mbytes per sec max
Search speed (max)
400x normal (3260 mm per sec)
Average access time
90 m cartridge
120 m cartridge
125 m cartridge
<30 sec
<40 sec
<40 sec
Drum rotation speed
10,000 RPM (all DDS modes)
Tape speed
20.375 mm per sec.
Head-to-tape speed
20.4 mm per sec.