HP 7942 Service Manual page 130

Backdating Information
7942 and 7946
C.
Remove the top shroud (refer to paragraph
A5-4) and the front panel (refer to paragraph
A5-7).
d. Disconnect connector P I on ribbon cable assemb-
ly W6 (27) from connector J2 on tape drive
DOC UI-FRA2 (50). (Connector PI can be
reached through the opening in the side of the
mainframe assembly.)
e. Disconnect connectors P3 and P4 on ribbon cable
assembly W3 (37) from connectors Jl and J2,
respectively, on disc drive assembly UO-FRA 1
(35).
f. Remove the two T 10 screws (23) which secure
the mounting bracket (24), with tape drive as-
sembly U I-FRA I (26) attached, to the
mainframe assembly (51).
,. Withdraw the mountinl bracket (24), with tape
drive assembly U I-FRA I (26) attached, from
the mainframe assembly.
h.
Disconnect connector P
8
on power cable assemb-
ly WI (38) from connector J3 on tape drive as-
sembly UI-FRAI (26).
i. Remove the four TIO screws (25) which secure
tape drive assembly UI-FRAI (26) to the
mountinl bracket (24) and remove tape drive
assembly UI-FRAI (26).
j.
Disconnect connectors P2, P3 on ribbon cable as-
sembly W6 (27) from their mating connectors
on tape drive assembly UI-FRAI (26).
Note: Further disassembly of tape drive
assembly U 1-FRA 1 is described in
the Tape Drive Service Manual,
Section V, Replaceable Parts.
Reinstallation is a reversal of the removal proce-
dure. Ensure that the cable assembly connectors
disconnected in steps d, e,h, and
j
are firmly seated
in their mating connectors.
AS-9. FAN
To remove the fan (31), proceed as follows:
a. Perform the preparation for service procedure
outlined in paragraph AS-2.
AS-4
b. Ensure that the power cord is disconnected from
the -AC LINE connector on the rear panel of
the drive.
c. Remove the top shroud (refer to paragraph
A5-4), front panel (refer to paragraph AS-6),
and tape drive assembly (refer to paragraph
AS-8).
d. Remove the two 6-32 hex standoffs (8) and lock
washers (9) which secure the HP-IB connector
on HOC FRA S (6) to the rear panel of the
mainframe assembly (51).
e. Disconnect connector Pion cable assembly W2
(30) from connector J2 on HDC FRAS
(6).
Slide
HDC FRA5 (6) forward to provide access to the
fan (31).
f. Remove the TID screw (29) which secures cover
plate (28) to the rear panel of the mainframe as-
sembly (51).
I. Disconnect connector P2 on cable assembly W2
(30) from connector J2 on disc drive DDC
UO-FRA2 (49).
h. Disconnect connector P3 on cable assembly W2
(30) from connector JI in tape drive DOC
UI-FRA2 (50).
i. Release the fan (31) cable from the cable clamps
(58) on the mainframe assembly (51).
j.
Remove the four TIS screws (32) which secure
grille (33) and fan (31), with captive nuts (34)
attached, to the rear panel of the mainframe as-
sembly (51 ) ..
k. Release cable assembly W2 (30) from the cable
clamp (59) on mainframe assembly (51).
1.
Remove cable assembly W2 (30) from the
mainframe (51) by passinl the cable forward
out the front of the mainframe.
m. Turn the fan (31) counterclockwise until its
outer edge clears the top of the tape drive hous-
ing on the mainframe assembly. When the fan
is clear of the housing, remove the fan from the
drive.
Reinstallation is a reversal of the removal proce-
dure. When the fan is installed, ensure that the
fan cable is aligned with the cable clamps (S 8) on