1.1.1 System Support
As of this printing, the TLZ07 drive is supported by a variety of Digital
systems. Consult your Digital Sales Support representative for a list of
supported systems. Your particular system must have a standard SCSI (small
computer system interconnect) port, a KZQSA (Q–bus to SCSI adapter), or
HSD05 (DSSI bus to SCSI adapter).
1.2 Design Features
The TLZ07 cassette tape drive uses state of the art technology. The TLZ07
cassette tape drive’s design incorporates the Digital Data Storage (DDS)
recording format and Digital Audio Tape (DAT) recording technologies.
1.2.1 What is Digital Audio Tape (DAT?)
DAT technology provides a high recording density with a very low error rate
through the helical scan recording method. With this method of recording,
both the tape and the recording head move simultaneously. The read and write
heads are located on a rapidly rotating cylinder, or drum that is tilted at an
angle in relation to the vertical axis of the tape. This causes the tracks to be
recorded diagonally across the tape, resulting in an extremely high recording
density, far higher than what is achievable with stationary-head devices.
1.2.2 What is Digital Data Storage (DDS?)
DDS uses a recording format that supports the use of digital audio tape
for computer applications. The objectives of DDS are to maximize storage
capacity and performance, facilitate data interchange, and provide very fast
random access. In addition, this format has three levels of error correction,
which ensures high data integrity. The DDS-DC format, which is a superset
of the basic DDS DAT format, allows you to back up 8 gigabytes of data in
approximately 3 hours minimum with no operator intervention, assuming 2:1
compression ratio.
NOTE
Use of non-DDS media may result in degraded drive performance and
is not recommended by Digital Equipment Corporation.
1–2 TLZ07 Cassette Tape Drive Product Description
