AT&T Network Adapter 25, Installation And Maintenance Manual

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MAINTENANCE
USING THE DIGITAL TAPE UNIT
The Model DC4 Digital Tape Unit (DTU) or equivalent is extremely important
in system maintenance. System Translations are stored in the DTU and can
be accessed in the unlikely event that translations are lost during a system
f a i l u r e .
This section covers the following:
●
Setting Up the DTU
●
Saving Translations
●
Verifying Translations
●
Restoring Translations.
Setting Up the DTU
The DTU must be properly connected to the system before it can be used.
Refer to Section 2, “Installation” in this manual for connection information.
The DTU automatically turns on when ac power is applied.
The DTU must also be connected to the CPU/Memory CP. Normally, this
connection is made through port 3 in the octopus cable originating from the
CPU/Memory CP. This connection should be verified, however, because the
port can be reassigned from the SAT.
A high quality audio cassette tape should be used. Examples of acceptable
tapes are the Maxell UD XL-II C60 or C90, and the TDK SA C60 or C90.
Before operating the DTU, always follow these steps:
1.
2.
3.
4-14
Press the STOP/EJECT button on the unit. (The plastic cover pops
u p . )
Insert the cassette so the exposed portion of
unit’s buttons. Press the cassette downward
p l a c e .
Close the cover.
the tape faces
until it snaps
t h e
into