Hughes Model 230 Projector Service Manual

Chapter 4---Maintenance (Removal/Replacement)
Model 230 Service Manual4-15
Figure 4-11.   Horizontal/Vertical Deflection PCB.
4.12   Video Input Cards (VICs)
Instructions for installing, removing, editing and VIC Settings are covered in
Chapter 5 of the Model 230 Users Guide.
4.13   Video Amplifier PCB
The Video Amplifier PCB for the 3 CRTs is located under the Electronic Module,
on the bottom frame of the projector behind and under the CRT assemblies.
To remove a Video Amplifier PCB:
1.   Remove the...

Chapter 4---Maintenance (Removal/Replacement)
4-16Model 230 Service Manual
away from the rear of the projector. Use extreme care not to break any of these
connections when removing the CRT/Yoke Assembly.
4.   Carefully remove the Green CRT/Yoke Assembly by sliding it backward and
upward as far as possible before disconnecting the Green CRT Socket
Connector from the CRT neck. Use care to avoid bumping the CRT as it is
being removed and to avoid breaking any of the wires that connect from the
CRT Socket...

Chapter 4---Maintenance (Removal/Replacement)
Model 230 Service Manual4-17
10. Disconnect the 3 Focus cables that run from the CRT Socket Connectors to
the Focus connectors on the HVPS. NOTE: Observe that each of the 3
Focus cables (large, red wires that run from each CRT Socket Connector to
the Focus connectors on the HVPS) is joined near the CRT by a coupler plug
and jack. Disconnect (and label) the focus cables at these couplers.
11. Loosen the 6 pozidrive screws that secure the Video Amplifier PCB to...

Chapter 4---Maintenance (Removal/Replacement)
4-18Model 230 Service Manual
4.   Remove the 4 pozidrive screws (Figure 4-13) and lift the board out.
5.   Reinstall in the reverse order from above.
4.15   CRT/Yoke Assembly
 WARNING!!! The CRT/Yoke Assemblies should be handled with
extreme caution. If dropped they can implode and flying glass can cause severe
injury to personnel. Be careful not to bump or drop the CRT. Place in a safe area
immediately after removal.
Three CRT/Yoke Assemblies are located in...

Chapter 4---Maintenance (Removal/Replacement)
Model 230 Service Manual4-19
6.   Remove the wires from the cable clamp for the CRT/Yoke Assembly that is
being removed.
7.   Loosen the CRT Holder Ring (knurled knob in Figure 3-8). NOTE: The CRT
Holder Ring should be only hand-tight. If it cannot be removed by hand only,
a flathead screwdriver can be used in the slots on the CRT Holder Ring to
help loosen it. Do not use a tool of any kind to tighten this ring-it should be
hand tight only.
8. 
 CAUTION! For...

Chapter 4---Maintenance (Removal/Replacement)
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3.   Disconnect the connector on the top of the appropriate ILA® assembly.
(Figure 4-14).
Figure 4-15.  ILA® Assembly top view. The overlap screws shown are
visible after the 
ILA® assembly is removed.
4.   Loosen the two wingnuts at the top of the appropriate ILA® assembly (Figure
4-15).
5.   Slide the spring clip at the top of the ILA
® assembly backward (Figure 4-15).
This will free the ILA® assembly.
6.   Grasp the ILA
®...

Chapter 4---Maintenance (Removal/Replacement)
Model 230 Service Manual4-21
4.   Loosen the CRT Lens Stopper Ring (the thin collar just in front of the CRT
Holder knurled ring-Figure 4-14) and slide it off the back of the Relay Lens.
5.   Loosen the wing nut on top of the Relay Lens mount (the bracket at the rear
of the Relay Lens).
6.   Remove the 2 long hex bolts at the front of the Relay Lens (shown in Figure
4-15).
7.   Remove the 2 hex bolts at the rear of the Relay Lens (these bolts are level
with...

Chapter 4---Maintenance (Removal/Replacement)
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4.19   Prism Assembly
 CAUTION! The removal of the Prism Assembly requires
removing the Dichroic Mirror Assembly (X-Plate). In most cases this necessitates
an optical realignment. HJT does not recommend performing this
replacement in the field. Optical alignment is critical and requires projector
power to be on. This results in an additional safety hazard due to the high
intensity light beam emanating from the optical area with...

Chapter 4---Maintenance (Removal/Replacement)
Model 230 Service Manual4-23
Figure 4-17.   Dichroic Mirror Assembly.
Figure 4-18.   Prism Assembly mount. 

Chapter 4---Maintenance (Removal/Replacement)
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10. Remove the remaining three hex bolts from the rear of the Prism assembly.
These screws are located in the cavities where the ILA® assemblies were
removed.
11. The Prism is now free to be removed.
 CAUTION! The Prism assembly is heavy (about 70 lbs).
Use two people to lift it out of the projector.
12. Replace the Prism assembly in the reverse order.
4-20   Recommended Spares
It may be advisable to maintain a supply of spares...