Digital Equipment VR320 User manual

VR320MonitorServiceGuide
Order Number EK-VR320-SV-001
Digital Equipment Corporation

First edition, April 1990
The information in this document is subject to change without notice and should not
be construed as a commitment by Digital Equipment Corporation. Digital Equipment
Corporation assumes no responsibility for any errors that may appear in this document.
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Computer Software clause at DFARS 252.227–7013.
Copyright © Digital Equipment Corporation 1990
All Rights Reserved.
Printed in U.S.A.
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This document was prepared and published by Educational Services Development and
Publishing, Digital Equipment Corporation.

Contents
About This Manual v
1 Overview
1.1 Product Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1
1.1.1 RefreshRate ................................... 1–2
1.1.2 ModelVariations ................................ 1–2
1.2 Tools and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2
1.3 Recommended Spare Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–3
2 Troubleshooting
2.1 BeforeYouStart................................... 2–1
2.2 Troubleshooting Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . 2–1
2.3 Troubleshooting Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–2
3 Removing and Replacing FRUs
3.1 Procedures....................................... 3–1
3.1.1 Rear Cover Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2
3.1.2 Top Cover Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–6
3.2 Field Replaceable Units (FRUs) . . . . . . . . . . . . . . . . . . . . . . . 3–8
3.2.1 Interconnect Cable Removal . . . . . . . . . . . . . . . . . . . . . . . . 3–9
3.2.2 Deflection Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–10
3.2.3 Discharging the CRT . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–14
3.2.4 Power Supply Module Removal . . . . . . . . . . . . . . . . . . . . . 3–18
3.2.5 Power Supply Module Replacement . . . . . . . . . . . . . . . . . . 3–27
3.2.6 Video Casting Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–30
3.2.7 CRT/Chassis Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–35
3.3 CRT Disposal (Trained Service Personnel Only) . . . . . . . . . . 3–35
iii

iv Contents
4 Aligning the Video Monitor
4.1 Introduction...................................... 4–1
4.1.1 BeforeYouStart................................. 4–1
4.1.2 Displaying Screen Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–2
4.2 Monitor Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–3
4.3 Using the Radiance Meter . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–4
4.4 ColorAdjustments................................. 4–6
4.5 Deflection Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–13
4.5.1 Vertical Linearity (VLIN) . . . . . . . . . . . . . . . . . . . . . . . . . 4–16
4.5.2 Vertical Centering (VCEN) . . . . . . . . . . . . . . . . . . . . . . . . . 4–17
4.5.3 Height (HEIGHT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–18
4.5.4 Horizontal Phase, Horizontal Linearity, and Horizontal
Centering (HPHASE, HLIN, HCEN) . . . . . . . . . . . . . . . . . 4–19
4.5.5 Horizontal Width (WIDTH) . . . . . . . . . . . . . . . . . . . . . . . . 4–21
4.5.20 Side Pincushioning (PIN) . . . . . . . . . . . . . . . . . . . . . . . . . . 4–23
4.5.7 Trapezoid (TRAP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–25
4.5.8 Focus (FOCUS1, FOCUS2, DYN PHASE, HPARAB,
VPARAB)...................................... 4–27
5 Changing Refresh Rates
5.1 Refresh Rates of VR320 Monitors . . . . . . . . . . . . . . . . . . . . . 5–1
5.2 Changing the Refresh Rate . . . . . . . . . . . . . . . . . . . . . . . . . . 5–1
5.3 Product Variation Label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–2
A Alignment Screens
A.1 Circle-Crosshatch Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . A–1
A.2 All-WhitePattern.................................. A–2
A.3 Central Rectangle Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . A–3
A.4 AllEsPattern .................................... A–4
A.5 Color Bars I Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–5
A.6 Color Bars II Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–5

Contents v
B VR320 Documentation
Index
Figures
1–1 VR320 Color Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–1
3–1 Power Switch/Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–2
3–2 Removing the Power Cord . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–3
3–3 Removing the Signal Cables . . . . . . . . . . . . . . . . . . . . . . . . . . 3–4
3–4 Removing the Rear Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–5
3–5 Tilting the Top Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–6
3–6 Removing the Top Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–7
3–7 VR320 Field Replaceable Units . . . . . . . . . . . . . . . . . . . . . . . 3–8
3–8 Removing the Interconnect Cable . . . . . . . . . . . . . . . . . . . . . 3–9
3–9 Removing the Cable from the Deflection Module . . . . . . . . . . 3–10
3–10 Disconnecting Cables from the Deflection Module . . . . . . . . . 3–11
3–11 Removing the Deflection Module . . . . . . . . . . . . . . . . . . . . . . 3–12
3–12 Refresh Rate Switch on the Deflection Module . . . . . . . . . . . 3–13
3–13 Removing the CRT Anode Cable from the Clamp . . . . . . . . . 3–15
3–14 Discharging and Removing the CRT Anode . . . . . . . . . . . . . 3–17
3–15 Removing the Interconnect Cable from the Power Supply . . . 3–18
3–16 Removing the Dynamic Focus Cable . . . . . . . . . . . . . . . . . . . 3–19
3–17 Removing the Degauss Cable from the Power Supply . . . . . . 3–20
3–18 Loosening the Power Supply Screws . . . . . . . . . . . . . . . . . . . 3–21
3–19 Sliding the Power Supply Out (Partially) . . . . . . . . . . . . . . . . 3–22
3–20 Removing the LED Cable from the Power Supply . . . . . . . . . 3–23
3–21 Disconnecting the Focus Pack and Focus Cables . . . . . . . . . . 3–24
3–22 Removing the Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . 3–25
3–23 Removing the Focus Wires . . . . . . . . . . . . . . . . . . . . . . . . . . . 3–26
3–24 Refresh Rate Jumper on the Power Supply . . . . . . . . . . . . . . 3–27
3–25 Attaching the Focus Wires to the Power Supply . . . . . . . . . . 3–28
3–26 Removing Cables from the Video Casting . . . . . . . . . . . . . . . 3–31
3–27 Removing the Plug from the Video Casting . . . . . . . . . . . . . . 3–32
3–28 Removing the CRT Socket Connector . . . . . . . . . . . . . . . . . . . 3–33
3–29 Removing the Video Casting . . . . . . . . . . . . . . . . . . . . . . . . . 3–34

vi Contents
3–30 Crushing the Evacuation Point . . . . . . . . . . . . . . . . . . . . . . . 3–38
4–1 UserAdjustments ................................. 4–3
4–2 RadianceMeter ................................... 4–4
4–3 Using the Radiance Meter . . . . . . . . . . . . . . . . . . . . . . . . . . 4–5
4–4 Color Adjustment Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–6
4–5 G2Adjustment ................................... 4–7
4–6 Brightness and Contrast Controls . . . . . . . . . . . . . . . . . . . . . 4–8
4–7 Service Switch and Blue and Red Cutoff . . . . . . . . . . . . . . . . 4–9
4–8 Setting Service Switch to Normal Position . . . . . . . . . . . . . . . 4–11
4–9 Blue, Green, and Red Gain Controls . . . . . . . . . . . . . . . . . . . 4–12
4–10 Location of Deflection Adjustments . . . . . . . . . . . . . . . . . . . . 4–13
4–11 Using the Metric Measuring Tape . . . . . . . . . . . . . . . . . . . . . 4–15
4–12 Circle-Crosshatch Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–16
4–13 VCEN, VHOLD, and VLIN Controls . . . . . . . . . . . . . . . . . . . 4–17
4–14 Vertical Height Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–18
4–15 HPHASE, HLIN, and HCEN Controls . . . . . . . . . . . . . . . . . . 4–20
4–16 Measuring the Width of the Viewing Area . . . . . . . . . . . . . . 4–21
4–17 Horizontal Width Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–22
4–18 Video Area on Screen Bowed Out . . . . . . . . . . . . . . . . . . . . . . 4–23
4–19 Video Area on Screen Bowed In . . . . . . . . . . . . . . . . . . . . . . . 4–23
4–20 Pincushion Adjustment (PIN) . . . . . . . . . . . . . . . . . . . . . . . . 4–24
4–21 Screen Wider at Top . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–25
4–22 Screen Wider at Bottom . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–25
4–23 Trapezoid Adjustment (TRAP) . . . . . . . . . . . . . . . . . . . . . . . . 4–26
4–24 Focus Adjustment Controls . . . . . . . . . . . . . . . . . . . . . . . . . . 4–27
4–25 Circle-Crosshatch Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–28
5–1 Product Variation Label . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5–3
A–1 Circle-Crosshatch Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . A–1
A–2 All-WhitePattern.................................. A–2
A–3 Central Rectangle Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . A–3
A–4 AllEsPattern .................................... A–4
A–5 Color Bars I Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–5
A–6 Color Bars II Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A–5

Contents vii
Tables
1–1 Refresh Rates of Monitor Models . . . . . . . . . . . . . . . . . . . . . . 1–2
1–2 Tools and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1–2
1–3 VR320 Recommended Spare Parts . . . . . . . . . . . . . . . . . . . . . 1–3
2–1 Blank Screen, No Video or Raster . . . . . . . . . . . . . . . . . . . . . 2–3
2–2 Blank Screen, No Video but Raster Present . . . . . . . . . . . . . . 2–4
2–3 Loss of Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2–5
2–4 ColorProblems.................................... 2–6
2–5 Poor Display Quality: Color, Brightness, Geometry, or Focus 2–8
5–1 Refresh Rates of Monitor Models . . . . . . . . . . . . . . . . . . . . . . 5–1
5–2 Product Variation Label Information . . . . . . . . . . . . . . . . . . . 5–2

AboutThisManual
This guide describes how to service your VR320 monitor.
Guide Organization
This guide covers the following topics:
• Chapter 1 provides a general overview of the product and includes a
list of spare parts.
• Chapter 2 describes the troubleshooting procedures.
• Chapter 3 provides the removing and replacing procedures for the
Field Replaceable Units (FRUs).
• Chapter 4 describes the alignment procedures.
• Chapter 5 describes the procedures to change the refresh rate of the
monitor.
• Appendix A describes the alignment screens.
• Appendix B describes related documentation.
Audience
The procedures in this guide are for service technicians trained only by
Digital Equipment Corporation.
Conventions
Warning Provides information to prevent personal injury.
Caution Provides information to prevent damage to the equipment.
Note Provides general information you should be aware of.
PN Part number.
v

1
Overview
1.1 Product Description
The VR320 color monitor (Figure 1–1) has a direct viewed, 485 mm,
antiglare CRT with contrast enhancement. The built-in tilt-swivel
assembly lets the user adjust the screen for viewing comfort. When
connected to a host system, the monitor can display information sent to
the host system and information the host system sends to it.
MA-0244-90.DG
Figure 1–1 VR320 Color Monitor
1–1

1–2 Overview
1.1.1 Refresh Rate
The monitor operates at a refresh rate of either 66 Hz or 72 Hz. It is
preset for the system as ordered. If you change the monitor to another
system, check the refresh rate of the new system and then set the switch
on the deflection module and the jumper on the power supply module to
match the new system. Refer to Chapter 5.
1.1.2 Model Variations
Table 1–1 lists the different VR320 models and their refresh rates.
Table 1–1 Refresh Rates of Monitor Models
Model Pixels x Lines Refresh Rate Applicable Area
VR320-CA 1280 x 1024 66 Hz Northern Hemisphere
VR320-C4 1280 x 1024 66 Hz Southern Hemisphere
VR320-DA 1280 x 1024 72 Hz Northern Hemisphere
VR320-D4 1280 x 1024 72 Hz Southern Hemisphere
1.2 Tools and Equipment
You need the following tools and equipment to service the VR320
monitor:
Table 1–2 Tools and Equipment
Tools and Equipment Part Number
Terminal Technician Tool Kit 29-27340-01
Static protection kit 29-26246-00
Anode discharge tool 29-24717-00
Metric measuring tape 29-25342-00
Safety goggles 29-16141-00
Gloves 29-16146-00

Overview 1–3
1.3 Recommended Spare Parts
The following are the recommended spare parts for the VR320 monitor:
Table 1–3 VR320 Recommended Spare Parts
Spares Part Number
Power supply module 54-19621-01
Deflection module 54-19301-01
Video casting assembly 70-27010-01
Interconnect cable 70-27000-01
CRT/chassis assembly 70-27429-03
CRT/chassis assembly 70-27429-04

2
Troubleshooting
This chapter describes how to troubleshoot a VR320 monitor problem
through fault isolation.
2.1 Before You Start
The following information will help you troubleshoot the monitor easily
and effectively:
WARNING
If you smell burning components, press the monitor power switch
to off and disconnect the power cord.
• If you are going to service a display quality type of problem, tell
the customer to let the monitor warm up for at least 20 minutes, if
possible, before you arrive and begin the troubleshooting procedures.
• Magnetic fields affect monitor performance and can give a false
indication of a monitor failure. Place the monitor away from any
electromagnetic devices, such as printers and terminals, or away from
large magnetized objects, such as filing cabinets and steel beams in
walls.
NOTE
Any time you replace a video casting assembly, deflection module,
or power supply module, perform all the necessary adjustments.
Refer to Chapter 3.
2.2 Troubleshooting Procedures
These procedures assume that only one assembly has failed or only one
problem exists. Always troubleshoot the most obvious symptom first.
However, one symptom may indicate multiple failures. Problems may
come from either the host system or the monitor.
2–1

2–2 Troubleshooting
Troubleshoot the VR320 monitor as follows:
1. Ask the operator to describe the problem. The operator often is the
most knowledgeable person.
2. Identify the problem. The screen display often indicates which
problem is occurring.
3. Isolate the problem. Refer to the troubleshooting tables to find the
suggested solutions.
4. Display the host system alignment test patterns to make sure that
no other problem exists. Refer to the host system service guide for
displaying test patterns.
2.3 Troubleshooting Tables
The troubleshooting tables list the possible cause in order of probability.
This troubleshooting information applies to the following types of video
problems your VR320 monitor may exhibit:
• A blank screen, without video or raster (Table 2–1)
• A blank screen, without video, but raster present (Table 2–2)
• Loss of synchronization (Table 2–3)
• Color problems (Table 2–4)
• Poor display quality: color, brightness, geometry, or focus (Table 2–5)
Use the troubleshooting tables as follows:
1. Note the general symptom of the problem.
2. Check the Symptom column for a match.
3. Check the conditions in the Possible Cause column in the order given.
4. Perform the action in the Suggested Solution column in the order
given.
NOTE
Any time you replace a video casting assembly, deflection module,
or power supply module, perform all the necessary adjustments.
Refer to Chapter 3.

Troubleshooting 2–3
Table 2–1 Blank Screen, No Video or Raster
Symptom Possible Cause Suggested Solution
Blank screen, no
video or raster.
Power to the monitor
is on (power switch
is in), but power
indicator is off.
Power cord is not
connected.
Low or no power
at wall outlet.
Connect the power cord to
the power source or monitor.
Use another power source. If
the problem continues, call
the facilities person.
Power supply module
is faulty. Replace the power supply module (Section 3.2.4).
Deflection module is
faulty. Replace the deflection module
(Section 3.2.2).
Video module is faulty. Replace the video casting
assembly (Section 3.2.6).
No video or raster,
but power indicator
is on.
Brightness or contrast
control is set too low. Adjust the brightness and contrast controls.
Internal cabling is
loose or faulty. Check all cabling connected to the deflection module and
the video casting assembly,
including the CRT socket. If
necessary, secure the cables.
Cutoff is set
improperly. Perform the cutoff alignment procedures (Section 4.4).
Deflection module is
faulty. Replace the deflection module (Section 3.2.2).
Video casting
assembly is faulty. Replace the video casting assembly (Section 3.2.6).
Power supply module
is faulty. Replace the power supply
module (Section 3.2.4).
CRT/chassis assembly
is faulty. Replace the CRT/chassis
assembly (Section 3.2.7) only
after trying all the other
solutions.

2–4 Troubleshooting
Table 2–2 Blank Screen, No Video but Raster Present
Symptom Possible Cause Suggested Solution
No video or cursor
is visible even when
the contrast control
is at maximum;
however, raster is
visible by adjusting
the brightness
control.
Host screen saver is
activated.
Power to the host
system is not on.
External signal
cables are
disconnected.
Press any key to reactivate the
display.
Turn power to the host system
on.
Connect the signal cables
at the monitor and the host.
Signal cable is faulty. Replace the signal cable.
Refer to the host system
documentation.
Host system is not
supplying video
signals to the
monitor.
Connect the monitor to a
known working host system
with the same refresh rate
(Chapter 5) and verify the
problem before replacing any
monitor modules.
Host system is
faulty. Repair the host system.
Internal cabling is
loose or faulty. Check all cabling connected
to the deflection module and
the video casting assembly. If
necessary, secure the cables.
Video casting
assembly is faulty. Replace the video casting
assembly (Section 3.2.6).
Deflection module is
faulty. Replace the deflection module (Section 3.2.2).
CRT/chassis
assembly is faulty Replace the CRT/chassis assembly (Section 3.2.7) only
after trying all the other
solutions.

Troubleshooting 2–5
Table 2–3 Loss of Synchronization
Symptom Possible Cause Suggested Solution
VR320 video display
with 4-bar color
pattern is out of
sync.
Incorrect refresh rate
setting. Check the refresh rate of the
host system and verify that the
monitor refresh rate matches
the host system.
Video cables are
faulty or improperly
connected.
If green is not present, connect
the video cables.
After connecting the video
cables and green is still not
present, swap the red and
green video cables at both the
monitor and host system.
If the display is now green
and in sync, replace the video
cable.
After connecting the video
cables and green is still not
present, swap the red and
green video cables at the
monitor. If the display is now
green and in sync, repair the
host system.
After swapping the red and
green video cables and the
display is green but out of
sync, go to the next probable
cause.
If green is present,
the problem is with
the monitor or host
system.
If another VR320 monitor is
available, swap the monitors
and see if the problem
continues.
If the problem continues,
repair the host system. If the
problem does not occur, the
problem is in the monitor.
If another VR320 monitor
is not available, replace
the deflection module
(Section 3.2.2).

2–6 Troubleshooting
Table 2–3 (Cont.) Loss of Synchronization
Symptom Possible Cause Suggested Solution
Deflection module is
faulty. Replace the deflection module
(Section 3.2.2).
If the problem
continues, the video
casting assembly is
faulty.
Replace the video casting
assembly (Section 3.2.6).
If the problem still
continues, the host
system is faulty.
Repair the host system.
NOTE
Make sure the monitor has warmed up for at least 20 minutes
before you use Table 2–4. Refer to Appendix A for the color
patterns.
Table 2–4 Color Problems
Symptom Possible Cause Suggested Solution
Wrong color display. When
4-color bar pattern is
displays, the primary colors
are not in their proper
sequence.
Video cables are
crossed. Swap the video cables.
Red or blue color is missing.
Missing color is restored
when red and blue cables
are swapped at both the
monitor and host system.
Color that was present is
now missing.
Signal cable is faulty. Replace the signal
cable. Check that the
cables are installed in
the correct connectors.
Red or blue color is missing.
Missing color is restored
when red and blue cables
are swapped at the monitor.
Host system is
faulty. Repair the host system.

Troubleshooting 2–7
Table 2–4 (Cont.) Color Problems
Symptom Possible Cause Suggested Solution
Green color is missing, but
video is in sync. Swap red and green
video cables at the
monitor. If green
is still missing, the
problem is in the
monitor.
Repair the monitor.
If green is restored,
the problem is in the
host system.
Repair the host system.
Video casting
assembly is faulty. Replace the video casting assembly
(Section 3.2.6).
CRT/bezel/chassis
assembly is faulty. Replace the CRT/chassis assembly
(Section 3.2.7) only
after trying all the
other solutions.

2–8 Troubleshooting
Table 2–5 Poor Display Quality: Color, Brightness, Geometry, or Focus
Symptom Possible Cause Suggested Solution
Poor centering. Centering controls
on top of the monitor
or on the deflection
module are set
incorrectly.
Adjust the centering controls
on top the monitor and check
the deflection adjustments.
Refer to Chapter 4.
Poor geometry,
and/or linearity. Monitor is out of
adjustment. Perform appropriate adjustments. Refer to
Chapter 4.
Deflection module
assembly is faulty. Replace the deflection module assembly (Section 3.2.2)
and perform all deflection
adjustments.
Poor color purity.
Different colors
can be seen when
an all-red pattern
displays.
Monitor needs to be
degaussed. Press the degauss button to
correct color distortions.
Local magnetic
fields. Remove any electromechanical
devices from the vicinity of the
monitor, or move the monitor
to another location.
CRT/chassis
assembly is faulty. Replace the CRT/chassis
assembly (Section 3.2.7) only
after trying all the other
solutions.
Poor light output
(using the all-white
diagnostic pattern)
Brightness or
contrast controls
set too low.
Adjust the brightness and
contrast controls.
Video casting
assembly is out of
adjustment.
Perform the color adjustments.
Refer to Chapter 4.
Host system is not
supplying correct
signal levels.
Repair the host system.
Video casting
assembly is faulty. Replace the video casting assembly (Section 3.2.6).

Troubleshooting 2–9
Table 2–5 (Cont.) Poor Display Quality: Color, Brightness, Geometry, or
Focus
Symptom Possible Cause Suggested Solution
CRT wearout Replace the CRT/chassis
assembly (Section 3.2.7) only
after trying all the other
solutions.
Poor color balance. Video casting
assembly is out of
adjustment.
Perform all color adjustments.
Refer to Chapter 4.
Signal levels from
the host system
are not properly
balanced.
Repair the host system.
Video casting
assembly is faulty. Replace the video casting assembly (Section 3.2.7).
CRT/chassis
assembly is faulty. Replace the CRT/chassis
assembly (Section 3.2.7) only
after trying all the other
solutions.
Display is not clear
or sharp. Focus is out of adjustment. Perform focus adjustment. Refer to Chapter 4.
Cutoff and Gain
settings are too high. Readjust the cutoff and gain settings. Refer to Chapter 4.
Internal cabling is
loose or faulty. Check all cabling connected to the deflection module and
the video casting assembly. If
necessary, secure the cables.
Power supply module
is faulty. Replace the power supply
module (Section 3.2.4).
Video casting
assembly is faulty. Replace the video casting assembly (Section 3.2.7).
Deflection module
assembly is faulty. Replace the deflection module assembly (Section 3.2.2)
and perform all deflection
adjustments.