4-74
Assembly Access
HP
98760A Standard Color Graphics Display
This section contains assembly access procedures for the replaceable parts
in
the
HP
98760A
display. This manual provides these procedures because the
98760A
does not have
its
own service
manual. If
the
HP
98770A
High-Performance Color Graphics Display
or
the
HP
98780A
Monochromatic Display
is
used with the computer, refer to the appropriate display service manual
for access procedures.
The alphalinterface
board
is
mounted
to the bottom of the display. The procedure to remove the
alpha/interface
board
is
provided previously
in
this chapter.
This section contains assembly access procedures for the following replaceable assemblies:
• Display power supply
board
•
Sweep
board
• Display motherboard
•
RFI
board
• Graphics/digital video
board
• Video
board
• CRT/yoke assembly
• Fan
WARNING
THE PROCEDURES
IN
THIS SECTION ASSUME THAT THE AC
POWER CORD HAS
BEEN
UNPLUGGED
FROM
THE DISPLAY
AND THAT THE DISPLAY HAS
BEEN
REMOVED FROM THE COM-
PUTER. DISPLAY REMOVAL
IS
DESCRIBED PREVIOUSLY IN
THIS
CHAPTER.
CRT
Safety
Precautions
Observe the following safety precautions whenever you are working with
or
near
the CRT.
WARNING
THE CRT CAN IMPLODE
IF
DROPPED, HIT BY A TOOL
OR
OTHER OBJECT,
OR
SUBJECTED TO
STRESS
EXCEEDING THE
GLASS STRENGTH. THE
MOST CRITICAL
AREA
OF
THE EN-
VELOPE
IS
THE FUNNEL
AREA.
A BREAK IN THIS AREA WILL
ALMOST ALWAYS RESULT IN AN IMPLOSION.
• Handle the CRT with care to avoid breakage
and
possible implosion of the CRT envelope.
• Always wear safety glasses.
• Use a protective
shop
jacket
or
coat.
• Use a rubber
mat
or
carpet
on
the floor
in
the working area to reduce the possibility of
breakage
if
dropped.
•
When
the CRT
is
removed from the chassis, place
it
face down
on
a soft pad, upholstered
chair,
or
magazine, etc.