Figure 9-22.—A magnetic tape cartridge.
standard cartridge uses 600 feet of 1/4-inch tape.
Instead of reflective markers, holes punched in the tape
are used to indicate BOT/EOT.
The unit contains four read/write heads. Data may
be written on or read from four addressable tracks (0, 1,
2, or 3). Separate data maybe stored in each track, or
tracks may be used as a continuation of the previously
selected track. Data is stored serially one bit at a time
down the length of the track. Up to 60 megabytes of data
may be stored on one 600-foot cartridge.
Cartridge units are slower than standard tape drives,
but the cartridges are more rugged and easily
transported. In addition, the cartridge unit has less
moving parts than the standard tape drive, which
contributes to increased unit reliability and
,
maintainability.
TOPIC 3—MAINTENANCE
REQUIREMENTS
Preventive maintenance of magnetic tape devices
consists of performing mechanical and electrical
alignments and testing the tape units using several
different maintenance programs.
ALIGNMENT
Magnetic tape units require many mechanical and
electronic adjustments/alignments. Some of these
adjustments are required only during unit installation.
Others must be done when a faulty component or
assembly is removed and/or replaced. Still others are
needed because of normal equipment usage (wear and
tear).
Alignment checks or adjustments required on a
periodic basis are covered by the Planned Maintenance
System (PMS) Maintenance Index Page (MIP) and
Maintenance Requirement Cards (MRCs) that apply to
the unit you are maintaining.
You may find nonperiodic adjustment procedures
or technical specifications for periodic alignment
checks in the technical manual for the magnetic tape
device in your system.
9-19
