Hp 98760A Standard Color Graphics Display - HP 9020 Service Manual

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.