Hughes Jvc 200 Projector Service Manual

							Chapter 4---Maintenance (Removal/Replacement) 
2.   Remove the 2 flathead screws that secure the VIC to the 
projector rear panel. 
3.   Grasp the VIC connector bracket and pull the VIC out 
(Wiggle the VIC a little, if necessary, to extract it). 
4.12   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 front and rear covers (Section 4.2). 
2.   Tilt the Electronic Module up (Section 3.3). 
3.   Loosen the Green CRT Holder Ring (knurled knob-see 
Figure 3-5). Read the Caution below this step before 
removing the CRT Holder Ring completely. NOTE: The 
holder ring should only be hand-tight. If it cannot be 
removed by hand, a flathead screwdriver can be used in 
the slots on the CRT Holder Ring (Figure 3-5) to help 
loosen it. Use care not to let the flathead screwdriver slip 
out of the slot and possibly damage components. Do not 
use a screwdriver or any other tool to tighten this ring-it 
should be hand-tight only.  
CAUTION! This step is performed with the CRT Socket 
Connector still connected to the Green CRT and the ground 
wire still connected from the CRT/Yoke Assembly to the CRT 
Socket Connector. This is because the Green CRT Socket 
Connector is close to the rear of the projector and is easier to 
disconnect from the CRT after the CRT/Yoke Assembly is 
loose and is moved 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 Connector to the Video 
Amplifier. 
5.   Move the Green CRT/Yoke Assembly away from the rear 
of the projector, then disconnect the Green CRT Socket 
Connector and the ground wire between the CRT/Yoke 
Assembly and the CRT Socket Connector. NOTE: It may 
be helpful to perform this step with a partner-one person 
to hold the CRT/Yoke Assembly firmly and the other to 
remove the CRT Socket Connector and the ground wire. 
6.   Gently lay the Green CRT Socket Connector on the top of 
the Video Amplifier PCB. 
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							 Chapter 4---Maintenance (Removal/Replacement) 
7.   Place the Green CRT Assembly in a safe location on or 
against one of the other CRT Assemblies. 
8.   Disconnect the Red and Blue CRT Socket Connectors 
and gently lay them on the top of the Video Amplifier 
Board. 
9.   Disconnect the 3 connectors (push in slightly, squeeze 
the tabs, and pull out), J67, J68, and J69 from the Video 
Amplifier PCB. Move the cables out of the way. 
 
Figure 4-9.   Video Amplifier PCB showing breakaway CRT Socket 
Connectors. 
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 the projector frame. 
12. Make sure everything is out of the way, then slide the 
Video Amplifier PCB toward the left so the mounting 
screws will clear the access holes and remove the board 
from the projector.  
13. Reinstall in the reverse order from above. NOTE: The 
Video Amplifier PCB is shipped with the 3 CRT Socket 
Connectors attached at the end in a “breakaway” 
arrangement (Figure 4-9). Use a pair of diagonal cutters 
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							Chapter 4---Maintenance (Removal/Replacement) 
and carefully cut the socket connectors away from the 
Video Amplifier PCB. The spacers between the CRT 
Socket Connectors can be discarded. 
4.13   Scan Reversal PCB 
The Scan Reversal PCB is located on the right side of the Electronic 
Module. 
To remove the Scan Reversal PCB: 
1.   Remove the projector rear cover. 
 
Figure 4-10.   Scan Reversal PCB. 
2.   Disconnect 7 connectors; J52, J54, J64, J65, J66, J50 (or 
J50A), and J100 (or J101). To remove, push in slightly, 
squeeze the tabs, then pull connector out. 
3.   Move all cables out of the way. 
4.   Remove the 4 pozidrive screws (Figure 4-10) and lift the 
board out. 
5.   Reinstall in the reverse order from above. 
4.14   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. 
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							 Chapter 4---Maintenance (Removal/Replacement) 
Three CRT/Yoke Assemblies are located in the CRT Assembly area 
below the card cage. To remove a CRT/Yoke Assembly (refer to 
Figure 4-11): 
 
Red ILA 
Green ILA 
Metal-Framed 
Air Filter 
behind grille. 
CRT/Yoke 
Assemblies 
Air Filter on 
bottom. 
Cable Harness 
to Scan 
Reversal PCB Relay 
Lenses Rollbar Bracket 
CRT Lens 
Stopper Ring 
Blue ILA 
Video Amplifier 
PCB below 
CRTs
Figure 4-11.   View of CRTs, Relay lenses and ILA® 
Assemblies. 
1.   Remove front and rear covers (Section 4.2). 
2.   Tilt the Electronic Module up and lock it in place (Section 
3-3). 
3.   Remove the two pozidrive screws from the top of the High 
Voltage Power Supply (HVPS) cover (Figure 4-5) and 
loosen the one screw at the bottom of the cover (do not 
remove the bottom screw-it is difficult to replace-the 
HVPS will slide up and over it). 
4.   Remove the CRT anode cable (for the CRT that is to be 
replaced) from the HVPS. 
5.   Disconnect the Yoke plug and cable harness from the 
Scan Reversal PCB for the appropriate CRT (see Figure 
3-7). 
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 3-5). 
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. 
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							Chapter 4---Maintenance (Removal/Replacement) 
8.   CAUTION! For the Green CRT/Yoke Assembly only, 
this step is best performed with the Green CRT still 
connected to the CRT socket connector and the ground 
wire still connected from the CRT to the socket connector. 
This is because the Green socket connector is close to 
the rear of the projector and is easier to disconnect from 
the CRT after the CRT/Yoke Assembly is loose and is 
moved away from the rear. Be careful not to break any of 
these connections.  
Gently remove the CRT/Yoke Assembly by sliding it 
backward and upward as far as possible before 
unplugging the CRT socket connector from the neck. Use 
caution to avoid bumping the CRT/Yoke Assembly as it is 
being removed. 
9.   After removing the CRT/Yoke Assembly, carefully unplug 
the CRT socket connector and the ground wire that 
connects the CRT to the socket connector. NOTE: It may 
be helpful to have another person assisting for step 9. 
One person can unplug the CRT socket connector and 
ground wire, while the other person holds the CRT/Yoke 
Assembly firmly. 
10. After verifying that all cables are out of the way, remove 
the CRT/Yoke Assembly from the projector. 
11. Reinstall the CRT/Yoke Assembly in the reverse order. 
NOTE: When reinstalling the CRT/Yoke Assembly, plug 
the CRT ground wire into the CRT Socket Connector first, 
then partially plug in the Green socket connector into the 
CRT. When the CRT is completely installed it will be 
easier to fully insert  the CRT into the socket connector. 
12. Perform a CRT Mechanical focus adjustment (Section 
3.5) and CRT Rotation (Section 3.6) after replacing the 
CRT/Yoke Assembly. Check the CRT Mechanical Focus 
on the other two colors to verify that they are still correct. 
It is possible the other focus adjustments could have been 
disturbed by the removal and replacement of the 
CRT/Yoke Assembly. 
4.15   ILA® Assembly 
To remove an ILA® Assembly: 
1.   Remove the rear cover (Section 4.2). 
2.   Tilt up the Electronic Module (Section 3.3). 
3.   Disconnect the connector on the top of the appropriate 
ILA® assembly. (Figure 4-11). 
 
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							 Chapter 4---Maintenance (Removal/Replacement) 
 
Figure 4-12.  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 4-12). 
5.   Slide the spring clip at the top of the ILA® assembly 
backward (Figure 4-12). This will free the ILA® assembly. 
6.   Grasp the ILA®  assembly by its housing and slide it out.  
7.   Replace the ILA® in the reverse order from above. 
8.   Recheck convergence, shading, ILA® bias and G2 and 
readjust, if necessary (User’s Guide, Sections 5.8, 5.10, 
5.7, 5.9). 
9.   Recheck the ILA® Back Focus (Section 3.4) and the ILA® 
Overlap adjustment (Section 3.8). 
4.16   Relay Lens 
To remove a Relay Lens (refer to Figure 4-11): 
1.   Remove the rear cover (Section 4.2). 
2.   Tilt up the Electronic Module (Section 3.3) 
3.   Remove the corresponding CRT Assembly behind the 
Relay Lens that is to be removed. 
4.   Loosen the CRT Lens Stopper Ring (the thin collar just in 
front of the CRT Holder knurled ring-Figure 4-11) and 
slide it off the back of the Relay Lens. 
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							Chapter 4---Maintenance (Removal/Replacement) 
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 4-12). 
7.   Remove the 2 hex bolts at the rear of the Relay Lens 
(these bolts are level with the bottom of the Relay Lens 
and hold the bracket in place). 
8.   Remove the Relay Lens. Leave the Relay Lens Bracket 
and the CRT Lens Stopper Ring in the projector-do not 
send them back with the Relay Lens. 
9.   Replace the Relay Lens in reverse order from above. 
4.17   Projection Lens 
To remove the Projection Lens: 
1.   Remove the sponge cover from around the front of the 
Projection Lens. 
2.   Disconnect and label the Projection Lens Focus and 
Zoom motor cables (The Focus motor is at the top of the 
Projection Lens. The Zoom motor is at the bottom.) 
3.   Loosen (do not remove) the hex locking screw at the right 
side (Figure 4-13) of the Projection Lens. 
4.   Rotate the Projection Lens left or right so that the notch 
on the lens clears the locking screw on the lens holder 
(Figure 4-12). Carefully slide the lens out.  
 
Locking screw 
Notch may be above 
or below the holding 
screw, depending on 
how lens was 
installed 
Figure 4-13.   Projection Lens locking screw and removal notch. 
WARNING!!! If the locking screw is in line with the notch shown, the 
lens can fall out if the projector is pointed downward. 
5.   Replace the Projection Lens in reverse order. NOTE: The 
same basic procedure above is used to install or remove 
optional fixed lenses. 
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							 Chapter 4---Maintenance (Removal/Replacement) 
NOTE: When changing from a zoom to a fixed lens, or vice 
versa, the ILA® Back Focus (Section 3.4) may need 
readjustment. 
4.18   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 the optical cover off. If 
removal and replacement is absolutely necessary, proceed with 
extreme caution and wear safety glasses. 
The Prism Assembly requires the removal of more components and 
assemblies than any of the other assemblies. Be sure to have 
storage cabinets or tables to house the various items as they are 
removed to provide access to the Prism Assembly. Allow about 3-4 
hours to perform the removal and replacement of the Prism 
Assembly. Refer to Figures 4-1 and 4-11 for the assemblies 
referenced in this procedure. 
To remove the Prism Assembly: 
1.   Remove front and rear covers (Section 4.2). 
2.   Remove the Optical Shield by removing the 3 screws 
holding it. 
3.   Remove the Arc Lamp air filter and cover (3 screws). 
4.   Remove the Arc Lamp (Section 4.4). 
5.   Remove the Lamphouse Dock (Section 4.4). 
6.   Remove the lower right side panel (5 screws). 
7.   Remove the X-Plate (Dichroic Mirrors) assembly by 
removing the four hex bolts securing it (see Figure 4-14). 
CAUTION! Use care when lifting the mirror assembly. 
Place it in a safe, level storage area. 
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							Chapter 4---Maintenance (Removal/Replacement) 
 
Figure 4-14.   Dichroic Mirror Assembly. 
8.   Remove the 2 hex bolts from the front of the Prism 
assembly (see Figure 4-15). 
 
Figure 4-15.   Prism Assembly mount. 
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							 Chapter 4---Maintenance (Removal/Replacement) 
9.   Remove the Rollbar assembly (2 pozidrive bolts/nuts on 
left side and two nuts on right side). Disconnect and label 
the 2 connectors on the hinge assembly for the shutter 
motors (1 in front and 1 in rear). Remove and label the 
jumper that connects the front interlock switch to the rear 
interlock switch. 
10. Remove the Rollbar Bracket that was holding up the left 
side of the Rollbar assembly. 
11. Remove the 3 ILA® asssemblies (Section 4.15). 
12. 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 (see Figure 4-
15). 
13. 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. 
14. Replace the Prism assembly in the reverse order. 
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