Installing The Dsu; Use Of Head Cam Alignment Tool - HP 7925D Service Manual

7925
Alignment and Adjustment
INSTRUCTIONS
OJ
LOOSEN KNUR LED SCREWS
o
SLIDE ALIGNMENT TOOL ONTO SPINDLE HUB
o
ENSURE THAT ALIGNMENT TOOL BUTTS UP AGAINST CAMS
m
SECURE ALIGNMENT TOOL ON SPINDLE HUB, USING KNURLED SCREW
Figure 3-2. Use of Head Cam Alignment Tool
disc drive, and all alignment and adjustment procedures
which require the use of the DSU are provided in the
following paragraphs.
3-9. INSTALLING THE DSU
WARNING
Adjustments requiring the DSU are
performed with power supplied to
the disc drive, and protective covers
removed. Such maintenance should
be performed only by service-trained
personnel who are aware of the
hazards involved (for example, fire
and electrical shock).
To install the DSU, proceed as follows:
a. Disconnect the ac power cord from the ac mains
power.
b. Remove the shroud from the disc drive enclosure.
c. Loosen the three screws that secure the preamp shield and
remove the shield.
d. Disconnect the interconnect cable from J1 on I/O
sector PCA-A2.
e. Loosen the two screws that secure the card cage
cover and cable mounting bracket to the card cage
and remove the cover and mounting bracket.
f. Insert head alignment PCA, part no. 13354-60110, into
card slot AI. (See figure 3-4.) Ensure that the PCA is
correctly oriented, then firmly seat the PCA in the recepta-
cle. The component side of the PCA must face toward the
right side of th,e card cage as viewed from the front.
g. Hang the DSU Test Module, part no. 13354-60005, on the
top outer edge of the card cage.
3-3