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Document:	TK70 Streaming Tape Drive Owner's Manual
Order Number:	EK-0TK70-OM
Revision:	1
Pages:	36
Original Filename:

OCR Text

EK-OTK70-OM-001

TK70

Streaming Tape Drive
Owner's Manual

Prepared by Educational Services
of Digital Equipment Corporation

Ist Edition, July, 1987

The reproduction of this material, in part or whole, is strictly prohibited. For copy
information, contact the Educational Services Department, Digital Equipment
Corporation, Maynard, Massachusetts 01754.
The information in this document is subject to change without notice. Digital Equipment

Corporation assumes no responsibility for any errors that may appear in this document.
NOTICE: This equipment generates and uses radio frequency energy. It has been type
tested and found to comply with the limits for a Class B computing device in accordance
with the specifications in Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protection against radio and television interference in a residential installation. However, there is no guarantee that interference will not occur in a particular
installation. If this equipment does cause interference to radio or television reception, the
user is encouraged to try to correct the interference.
The following are trademarks of Digital Equipment Corporation, Maynard,
Massachusetts.

DECmate
DECnet
DECsystem-10
DECSYSTEM-20

DECUS
DECwriter
DIBOL
MASSBUS
PDP
P/OS

Professional
Q-Bus
Rainbow
RSTS
RSX
RT

UNIBUS
VAX
VAXstation
VMS
VT
Work Processor

Contents
Preface

vii

Chapter 1~ Overview
1.1

TK70 Description . . . .. ... ... .

1.2

TK70 Backup Performance . . . . ... .......
... 000y 1-2

i ittt 1-1

1.3

COMPACTape Il Tape Cartridge . ..................... 1-3

1.4

TK70 Specifications. . . . ... ........ ...

1.5

Related Documents

2-1

Light Summary

. . . . . .. .¢t i i i v v v ot ot

o e e

iiiiiiiiiiiiiiiiiiiiiiiiiiii

Preface

HOW TO USE THIS MANUAL

This manual is intended as an aid for first-time users of the TK70 tape
drive. We suggest you read this manual once completely before using the
TK70. When you are ready to use the TK70, turn to Chapter 2, Operating
Procedures.

Chapter 1 — Overview — briefly describes the TK70 tape drive, lists
operating system considerations, describes the COMPACTape II tape
cartridge, provides specifications, and lists related documents.

Chapter 2 — Operating Procedures — illustrates the controls and indicators on the front of the tape drive and explains their use. It provides a
step-by-step explanation of how to plug in, use, and remove a TK70 tape
cartridge.

Chapter 3 — Problem Resolution — explains how to identify and resolve
TK70 problems. This chapter provides symptoms and lists the most likely
cause of failure.

Chapter 4 — Services — lists the services that Digital Equipment Corpo-

ration provides its customers.

Appendix A — Standard VMS System Commands — lists some of the
VMS commands used with the TK70. It includes a series of steps for

backing up files on a TK70 using the VMS operating system.

Appendix B — Glossary — defines some of the terms commonly used in

this book.

vii

Chapter

Overview
1.1 TK70 Description
The TK70 is a streaming tape drive that stores up to 296 million bytes
(or characters) on each of its associated tape cartridges. It is used with
Digital microcomputer systems. Though the TK70 is physically small, it
has much of the functionality of Digital’s larger tape drives, like the TU81.
The TK70 fits a standard peripheral slot in your microsystem.

The TK70 can read data from a tape that was written by its predecessor,
the TK50. The TK50, however, cannot read data from a tape that has
been written by the TK70.

The TK70 is used primarily as a backup storage device, and to load
software onto Digital computer systems. For example, the VMS operating
system may be loaded from the TK70. The tape-distributed version of

VMS is loaded from a TK50-formatted tape.

The TK70 uses a tape cartridge (labeled COMPACTape II) that contains
the magnetic tafie on a single reel. This single reel is an important feature
to understand, because it affects the use of the TK70.
When you insert the tape cartridge into the drive, the tape is automatically
threaded onto a take-up reel inside the drive. When the tape has been
fully wound onto the take-up reel, it can take up to 90 seconds to rewind
completely. The tape must be fully rewound before you can remove the cartridge
from the tape drive. This procedure is different from a device that uses a
cartridge with two reels, such as a video cassette recorder (VCR). A VCR
tape can be ejected at any time—it doesn’t have to be rewound first.

Overview

1-1

Two main components comprise the TK70 subsystem: the drive unit is
one; a printed circuit board controller is the other. The controller is
plugged into the backplane of a Digital microsystem. Figure 1-1 shows

the
TK70 in a MicroVAX II computer system. A cable internal to the
system enclosure connects the controller to the drive.
Figure 1-1:

The TK70 in a MicroVAX Il

SHRA-0237.87

1.2 TK70 Backup Performance
You can enhance TK70 backup operation performance through the use of
various software "switches,” or command qualifiers, on the operating
system specific backup utilities. Each operating system has its own
backup utility, which is documented in the operating system specific
manual set. The value of these qualifiers to the performance of the TK70
is dependent upon the system in which the
TK70 resides, and on the
loading of that system. Refer to Appendix A, Standard VMS System
Commands, and the software manuals for your operating system.

1-2

Owerview

1.3 COMPACTape Il Tape Cartridge
The COMPACTape II tape cartridge, Figure 1-2, is a 10 by 10 cm (4
by 4 in) plastic cartridgle_ that can be used by the TK70 or TK50 tape
drives. The COMPACTape II is the successor to the COMPACTape

cartridge. The COMPACTape II is designed with t’i}hter tolerances than

the COMPACTape to support the higher recording densities of the TK70.
The COMPACTape II is the new standard, and eventually will replace the
COMPACTape cartridge.

The TK70 should use only the COMPACTape II tape cartridge to record
data. The TK70 is able to read any COMPACTape or COMPACTape
II cartridge originally written by the TK50. However, the TK70 cannot
overwrite a tape written by the TK50. The TK70 can only read data on that
tape. Before executing a command to the tape, the
TK70 determines if

the cartridge has been written by the TK50. If this is the case, the TK70
automatically write protects the tape. If the command you gave the TK70 was

a write command (like BACKUP or COPY), the operating system sends
a message that the tape cartridge is write protected and does not execute
that command.

Figure 1-2:

The COMPACTape Il Tape Cartridge
ORANGE
INDICATOR

PROTECT

SWITCH

SHR-0240-87

Overview

1-3

The labels provided with the COMPACTape II tape cartridge havg;(paces
for you to check whether the cartridge has been written by the TK50 or
the TK70. If you write data to the cartridge with the TK50, check the
block on the label that says 95 MB. If you write to the tape cartridge with
a TK70, check the block that says 296 MB. If you use both TK50 and TK70
drives, remember that the TK50 is unable to read or write tapes that have
originally been written by the TK70.
The tape cartridge has a write-protect switch to prevent accidental erasure
of data. When the switch is moved to the left and the small orange
rectangle is visible, data may not be written to the tape.

Inside the cartridge, a 608~foat single reel of magnetic tape stores data. A
plastic cartridge leader is at the beginning of the tape. Some guidelines
for COMPACTape cartridge use follow.

1-4

Do not drop or bang the cartridge. This may cause the leader to
be displaced, in which case the tape cartridge is unusable and may
damage the drive. (See Paragraph 3.5.1, Inspecting the Cartridge.)

Keep tape cartridges out of direct sunlight and away from heaters and
other sources of heat.

Store tape cartridges where the temperature is between 10 and 40°C
(50 to 104°F).

If the tape cartridge has been exposed to extremes of heat or cold, let
it stabilize at room temperature for the same amount of time it was
exposed—up to 24 hours.

Do not place cartridges near sources of electomagnetic interference,
such as terminals, motors, and video or X-ray equipment. Data on
the tape may be erased.

Store tape cartridges in a dust-free environment where the relative
humidity is between 20 and 80 percent.

Place an identification label only in the space provided for one on the
front of the cartridge.

Owverview

1.4 TK70 Specifications
Mode of Operation:

Streaming

Media:

12.77 mm (1/2 in) unformatted magnetic tape

Track Density:

96 tracks per inch

Bit Density:

10,000 bits per inch

Number of Tracks:

Transfer Rate (at host):

125 Kbytes per second

Tape Speed:

100 inches per second

Track Format:

Multiple track serpentine recording

Cartridge Capacity:

296 Mbytes, formatted (approx.)

Power Réa;jirements:

12V + 5% @ 1.6 A (2.4 A surge),

75 mV ripple peak-to-peak

+5V £ 5% @ 1.1 A (1.5 A surge),
75 mV ripple peak-to-peak
Power Consumption

Drive:

40 W, maximum

Host Adapter:

15 W, maximum

Querview

1-5

1.5 Related Supplies and Documentation
You should have a blank COMPACTape II tape cartridge, which you will
need to run tests on your TK70 subsystem.
The TK70 requires VMS version 4.6 or later releases.

Other operating

systems will support the TK70 in the future.

Table 1-1 lists the TK70 documentation available from Digital Equipment
Corporation,

Table 1-1:

Related Documents

Order No.

Title

TK70 Streaming Tape Drive Subsystem Technical Manual'
EK-OTK70-SM

TK70 Streaming Tape Drive Subsystem Service Manual

AA-Z407B-TE

VAX/VMS Backup Utility Reference Manual

Al-Y506B-TE

Guide to VAX/VMS Disk and Magnetic Tape Operations

AA-Z424A-TE

VAX/VMS Mount Utility Reference Manual

1Restricted distribution

1-6

Owverview

(MicroVAX II)

Chapter

Operating Procedures
This chagater provides operating instructions for the TK70 tape drive. The

operation section is divided into two parts: inserting and using the tape
cartridge, and removing the tape cartridge from the drive.

2.1 Controls and Indicators
The TK70 tape drive (Figure 2-1) has three lights, a beeper, an unload
switch, and a handle (the cartridge insert/release handle).

The fellewin§ garagraphs summarize the use of the switch and define the
conditions of the lights. See Paragraph 2.2, Operation, for an explanation
of how to insert, use, and remove tape cartridges.

2.1.1 Lights
Table 2-1
is a summary of the possible conditions of the lights.

Operating Procedures

2-1

Figure 2-1:

The TK70 Tape Drive

—

ORANGE:

| /WR!TE PROTECTED

°3

——— YELLOW:

TAPE IN USE

|
T———GREEN:

OPERATE HANDLE

BUTTON

SHAR-0251-87

2-2

Operating Procedures

Table 2-1:

Light Summary

Light

State'

Condition

Orange — Write Protected

On‘

Tape write protected

Off

Tape write enabled

Blinking?

Tape being used

Steady

Tape ready for use

OK to operate handle

Off

Don’t operate handle

Blinking

Cartridge error detected

Yellow — Tape in Use
Green — Operate Handle

1Al three lights blink to indicate a fault.
2Irregular blinking indicates that a read or write is in progress. Regular blinking indicates that

the tape is loading or unloading.

2.1.2 Beeper

A beep sounds when you can operate the handle. When you hear the

beep, the green light is on.

2.1.3 Unload Switch
The unload switch rewinds the tape. The tagz must be completely
before the cartridge can
rewound and unloaded back into the cartridge
be removed from the drive.

2.1.4 Cartridge Insert/Release Handle
To insert a tape cartridge, pull the cartridge insert/release handle to
the open position. To lock the cartridge in place, push the cartridge
insert/release handle to the closed position. To eject the cartridge after
it has been rewound, pull the cartridge insert/release handle to the open
position.

The handle may be pulled only when the green light is on, and after the
momentary beep sounds. (When you hear the beep, the green light is
on.)

Operating Procedures

2-3

2.2 Operation
2.2.1 Inserting and Using the Tape Cartridge
The numbered steps that follow correspond to Figure 2-2. Before you begin,
make sure the power is on.
1.

When the green light is on steadily, pull the handle to the open

position.

Insert the cartridge. |
Push the handle to the closed position. The green light turns off and
the yellow light begins to blink, indicating that the tag:e is loading.
When the tape is loaded (ready for use), the yellow light stays on
steadily. Whenever the yellow light is on steadily and it is the only
light on, the tape is ready to use.

NOTE
If the write protect switch on the cartridge is in the protected
position, the orange write protect light is on and you will be
unable to write data to the tape. If you move the write protect
switch to the enabled position during operation, the system
software does not recognize the fact that the tape is no longer
write protected. You must software unload, and then reload the
tape cartridge again before the software recognizes the cartridge
as write enabled.
|

Similarly, if you move the write protect switch from the write
enabled position to the write protected position during operation,
the tape is not actually write protected until the current command
is finished executing.

When the tape is being used (read, written, or rewound), the yellow light
blinks. If an error occurs during operation (reading/writing), all three

lights blink. If an error occurs when you are inserting the tape cartridge,
the green light blinks and the tape does not move. If this happens, refer
to Chapter 3, Problem Resolution.
When the yellow light is on steadily, you can proceed with your operation.
This operation may be to boot your operating system, or possibly, back up
files onto the TK70. Refer to your system documentation for instructions
on booting your operating system.

When a read or write is in progress, the yellow light blinks irregularly.

2-4

Operating Procedures

Figure 2-2:

Inserting the Tape Cartridge

SHR-0256-87

Operating Procedures

2-5

2.2.2 Removing the Tape Cartridge from the Drive
1.

Press the unload switch (Figure 2-3). You can lift the handle when
the green light comes on (the beep will also sound).

Pull the handle to the open position while the green light is on and

Push the handle to the closed position.

remove the cartridge.

CAUTION

When you remove a tape cartridge from the drive, return it to
its plastic case. Tape cartridges must be removed from the drive
before drive power is turned off. Failure to remove the cartridge
can result in damage to the cartridge and to the drive.

2-6

Operating Procedures

Figure 2-3:

Removing the Tape Cartridge

SHR-0257-87

Operating Procedures

2-7

Chapter

Problem Resolution
This chapter provides instructions to follow if your TK70 fails.

3.1 Correctable Failure During Tape Motion
If the TK70 fails during operation, you may be able to reset the fault and
then rewind, unload, and remove the tape cartridge.
If all three lights are blinking (indicating a failure),

press the unload

switch. If the detected error is correctable, the tape wil begin to rewind.
While the tape is rewinding, the yellow light is blinking. When the tape
has unloaded, the green light comes on and the beep sounds. You can
then pull the handle to the open position to eject the tape cartridge.

3.2 Non-Correctable Failure During Tape Motion
If the tape does not rewind when you push the unload switch and the
lights continue to blink, the error is not correctable. Call Digital Field
Service.

3.3 Failure During Cartridge Insertion
When the tape cartridge is damaged, or if internal portions of the drive
that handle the cartridge are not working, a cartridge fault occurs. If
the green light blinks and the tape doesn’t move (the yellow light does
not blink), a cartridge fault has been detected. Remove the cartridge
and try another. See also Paragraph 3.5.1, Inspecting the Cartridge, and
Paragraph 3.5.2, Inspecting the Drive Leader.

Problem Resolution

3-1

3.4 Testing
If you purchased diagnostics from Digital, follow the instructions you

received with your diagnostic tape or diskette to detect any problems

with the TK70 or other device on your system.

3.5 Inspection
If you have trouble loading a tape cartridge, it is a good idea to perform
a brief inspection of both the tape cartridge and the drive leader.

3.5.1 Inspecting thelfiCartrldge

Figure 3-1 shows the correct position of the tape leader inside the
cartridge. Before you attempt to use the tape cartridge, be sure the tape
leader is in the same position as the one in Figure 3-1. Lift the catch with
your thumb and open the small door to expose the leader.
CAUTION

Do not touch exposed portions of magnetic tape. If the tape leader

is not in the correct position, do not attempt to fix it. Use a new

cartridge instead.

3.5.2 Inspecting the Drive Leader
Compare the leader inside your drive with those shown in Figure 3-2. If

the leader is unhooked, misplaced, or damaged, call Digital Field Service.
Do not attempt to fix the leader.

Figure 3-1:

Inspecting the Cartridge Leader

DOOR LOCK

(RELEASE BY LIFTING
DOOR LOCK WITH THUMB)
SHR-0002-86

3-2

Problem Resolution

Figure 3-2:

Inspecting the Drive Leader

TAKE-UP
LEADER

NOTCH IN
LEADER

BUCKLING
LINK

/
CARTRIDGE INSERT/RELEASE
HANDLE (DOWN)

TAKE-UP

LEADER

BUCKLING

LINK

p ACCEPTABLE
CORRECT LOCATION
OF LEADER

)

LEADER
* UNHOOKED

UNACCEPTABLE
CALL FIELD SERVICE
TAKE-UP

LEADER
NOTCH

LEADER D!SPLACED
ABOVE
L

SHR-0249.87

Problem Resolution

3-3

Chapter

Digital Repair Service

ON-SITE SERVICE offers the convenience of service at your site and
insurance against unplanned repair bills. For a small monthly fee, you
receive personal service from our Service Specialists. Within a few hours,

the specialist is dispatched to your site with
you fast and dependable maintenance.

equipment and parts to give

BASIC SERVICE offers full cavera§e from 8 a.m. to 5 p.m., Monday
through Friday. Options are available to extend your coverage to 12-, 16-,
or 24-hour days, and to Saturdays, Sundays, and holidays.

DECservice offers a premium, on-site service providing committed response to remedial service requests made during contracted hours of
coverage. Remedial maintenance will be performed continuously until
the problem is resolved, which makes this service ideal for customers
requiring maximum service performance.

Under Basic Service and DECservice, all parts, materials, and labor are
covered in full.
CARRY-IN SERVICE offers fast, personalized response, and the ability
to plan your maintenance costs for a smaller monthly fee than On-Site
Service. When you bring your unit to one of 160 Digital Servicenters
worldwide, factory-trained personnel repair your unit within two days.
This service is available on selected terminals and systems. Contact your
local Digital Field Service office to see if this service is available for your
unit.

Digital Repair Service

4-1

Digital Servicenters are open during normal business hours, Monday
through Friday.

DECmailer offers expert repair at a per use charge. This service is
designed for users who have the technical resources to troubleshoot,
identify, and isolate the module causing the problem. Mail the faulty
module to our Customer Returns Center where the module is repaired
and mailed back to you within five days.

PER CALL SERVICE offers a maintenance program on a noncontractual,
time-and-materials-cost basis. This service is available with either OnSite or Carry-In Service. It is appropriate for customers who have the
expertise to perform first-line maintenance, but may occasionally need
in-depth support from Field Service.

Per Call Service is also offered as a supplementary program for Basic
Service customers who need maintenance beyond their contracted
coverage hours. There is no materials charge in this case.
On-Site Per Call Service is provided on a best effort basis, with a
normal response time of two to three days. It is available 24 hours a
day, seven days a week.

Carry-In Per Call Service is available during normal business hours,

with a two to three day turnaround.

For more information on these Digital service plans, prices, and special
rates for volume customers, call the Digital Field Service office nearest
you.

4-2

Digital Repair Service

Appendix

Standard VMS System Commands

A.1 VMS Commands Used with TK70
The TK70 uses all the standard magnetic tape commands that can be
invoked by your operating system. This section outlines some of the
major commands by which the VMS operating system accesses the TK70.
If you are using an operating system other than VMS, use the same
commands for the TK70 that you normally use for any magnetic tape
device. See the reference documentation supplied with your system.

The following command descriptions are written assuming the TK70 tape
cartridge is already in the drive and the TK70 is called MUAO by the
system. These commands have several qualifiers and options. For more
etailed information on these commands, refer to your operating system
manuals.

Standard VMS System Commands

A-1

A.1.1 ALLOCATE

ALLOCATE provides exclusive access to a device (such as the TK70)
and optionally establishes a logical name for that device. Once you
have allocated a device, other users cannot access that device until you
explicitly DEALLOCATE it, or until you log out. Use the following format
to allocate the TK70.

ALLOCATE MUAO:

[logical name]

Example: To allocate the TK70 for your use and assign it the logical name

TAPEL, type the following.
$ ALLOCATE MUAO: TAPE1l:

A.1.2 INITIALIZE
CAUTION

Make sure that the tape is blank before initializing. Any data on

the tape will be destroyed.

INITIALIZE writes directory information and file structure, specifies the
device name (MUAO, or TAPE1l), and writes a volume name to the
magnetic tape volume on the TK70. The tape must be write enabled
for the initialize operation. The command has the following format.
INITIALIZE logical name:

[volume name]

Example: To initialize the device called TAPE1 and assign the volume
name GMBO001, type the following.
$ INITIALIZE TAPEl: GMBOOlI

While the tape volume is being initialized, the yellow light blinks. When
the initialize is complete, the tape rewinds and then the yellow light stays
on steadily.

For detailed information regarding volume names and magnetic tape op-

erations, refer to the Guide to VAX/VMS Disk and Magnetic Tape Operations

(AI-Y506B-TE).

A-2 Standard VMS System Commands |

A.1.3 MOUNT

MOUNT lets you make a magnetic tafie volume available for processing.

With the TK70, MOUNT takes the following format.

MOUNT/FOREIGN/CACHE=TAPE logical name: volume name

Example: To make GMB001 on TAPE1 available for processing, type the
following,.
$ MOUNT/FOREIGN/CACHE=TAPE TAPEl: GMB0O1

When you MOUNT the tape volume, the yellow light blinks. The yellow
light stays on steadily when the tape reaches BOT. The console displays
a message such as GMB001 MOUNTED ON MUAQO:.

Generally, the MOUNT command allows you to perform either write or

read operations. However, you have an option to write protect the tape
volume by using the INOWRITE qualifier. Here is the command format.
MOUNT/FOREIGN/CACHE=TAPE/NOWRITE logical name: volume name

When you MOUNT the tape volume with the INOWRITE qualifier, the
orange light comes on and the yellow light blinks.
The /FOREIGN qualifier must be used when you
perform BACKUP
commands. It must not be used when you perform COPY commands.
For more information, see the VAX/VMS Mount Utility Reference Manual
(AA-Z424A-TE).

A.1.4 DISMOUNT
DISMOUNT cancels the previous MOUNT command (makes the unit
unavailable for processing) and rewinds the TK70 tape. To rewind and
unload the TK70 tape (to ready it for ejection from the drive), use the
following command format.
DISMOUNT logical name:

When the DISMOUNT command is invoked, the tape rewinds. As the
tape is rewinding, the yellow light blinks. When the rewind is complete
and the tape is ready for ejection, the green light comes on and the beep
sounds.
To rewind to BOT without unloading the tape, use this format.
DISMOUNT/NOUNLOAD logical name:

Standard VMS System Commands

A-3

While the tape is rewinding, the yellow light blinks. When the operation is
complete, the yellow light stays on steadily, indicating that the tape is again
ready for use,

A.1.5 BACKUP

BACKUP provides a means of protection against file volume corruption

by creating functionally equivalent backup copies.

To back up a file on the TK70, use this command format.
BACKUP/NOCRC/BUFF=5/BLOCK=16384 filename.ext devicename[logical name}:filename.bck

In addition to backing up single files, you can back up lists of files and
entire volumes. The yellow light blinks as the data is being written to the
tape.

By selecting the INOCRC, /BUFF=5, and /BLOCK=16384 qualifiers,
e comyou can achieve optimum performance from your TK70.
detecerror
CRC
e
host-availabl
the
of
use
the
mand line above excludes
checking
error
embedded
the
on
depends
and
capability,
ion
tion/correct
and correction capabilities of the TK70. Keep in mind that TK70 error
correction capabilities relate specifically to the TK70—not to the entire
system.

Use of the INOCRC qualifier requires a systems management decision
relative to data integrity vs. performance. In most instances, TK70
internal error detection and correction capabilities are sufficient to ensure
data integrity and recovery. The host-level CRC provides another level
of error detection and correction, which may be important under some
conditions.

Refer to your system manuals before deciding on qualifiers for use with
the BACKUP command. For detailed information about BACKUP, see
the VAX/VMS Backup Utility Reference Manual (AA-Z407B-TE).
You can also COPY files onto the COMPACTape Il tape cartridge. See
your operating system reference manuals for more information on the
COPY command.

A-4 Standard VMS System Commands

A.2 Backing Up on the TK70 with VMS
This section provides a general series of steps for backing up files on
a TK70 when you are using the VMS operating system.
The steps are
written assuming the TK70 is device MUAO, and that a tape has been
inserted.
1.

$ ALLOCATE MUAO(: TAPEL:

$ MOUNT/FOREIGN/CACHE
=TAPE TAPE 1:GMB001

$BACKUP/NOCRC/BUFF =5/BLOCK = 16384 filename.ext

$ DISMOUNT TAPEL:

$ DEALLOCATE TAPEl:

TAPE1:filename.bck

After step 5, you can remove the tape cartridge from the drive. Refer to

Paragraph-2.2.2.

Standard VMS System Commands

A-5

Appendix

Glossaryof Terms
BOT

Beginning of Tape. This is the first position on the tape where data can
be written. BOT is set automatically. You need perform no operations in
regard to BOT.
Cartridge Insert/Release Handle

This handle sets the internal mechanisms of the TK70 to accept or eject
the tape cartridge. The handle is pulled open to insert a tape cartridge,
pushed closed so the tape can be used, and pulled open again to eject
the cartridge after the tape has been completely rewound.
Cartridge Leader

A plastic leader at the beginning of the magnetic tagre. The mating of the
cartridge leader with the drive leader is like the threading of a needle.
The leader inside the cartridge serves as the ““eye’’ of the needle. This

plastic leader may be either black or white.
Drive Leader

A plastic leader inside the TK70. After the drive leader mates with the
cartridge leader, it draws the magnetic tape out of the tape cartridge and
onto the take-up reel inside the drive. As the tape is wound onto the
take-up reel, it passes the magnetic read and write heads.
insertion

Placing the tape cartridge in the TK70. The cartridge leader mates with
the drive leader during insertion.

Glossary of Terms

B-1

Load

When the tape cartridge has been inserted correctly and the leaders have
mated, the drive automatically winds the tape to BOT.

Unload Switch

A switch on the front of the tape drive that rewinds and unloads the
tape. When this operation is complete, the cartridge may be ejected.
The green light comes on and the beep sounds to indicate that you may
pull the handle to the open position and remove the cartridge.

Write Protect Switch

A switch on the COMPACTape II tape cartridge that prevents data from
being written to the tape. In its protected position, a small orange
indicator is visible on the front of the tape cartridge. In its write enabled
position, no orange rectangle is visible and data may be written to the
tape.

B-2

Glossary of Terms