DEC VR315, VR325 Service Manual

VR315andVR325MonochromeMonitors ServiceGuide

Order Number EK-VR315-SV-002

Digital Equipment Corporation

Second Edition, February 1991

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.

The software described in this document is furnished under a license and may be used or copied only in accordance with the terms of such license.

No responsibility is assumed for the use or reliability of software on equipment that is not supplied by Digital Equipment Corporation or its afﬁliated companies.

Restricted Rights: Use, duplication, or disclosure by the U. S. Government is subject to restrictions as set forth in subparagraph ( c) ( 1) ( ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227–7013.

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 vii

1 Overview

1.1 Product Description ................................ 1–1

1.1.1 Model Variations ................................ 1–2

1.2 Tools and Equipment ............................... 1–2

1.3 Recommended Spare Parts List ....................... 1–3

2 Troubleshooting

2.1 Before You Start. . . ................................ 2–1

2.2 Troubleshooting Procedures . . ........................ 2–2

2.3 Troubleshooting Tables.............................. 2–2

3 Removing and Replacing FRUs

3.1 Introduction ...................................... 3–1

3.1.1 Removing the External Cables ...................... 3–2

3.1.2 Removing the Rear Cover . ........................ 3–3

3.1.3 Removing the Top Cover . . ........................ 3–4

3.2 Field Replaceable Units (FRUs)....................... 3–5

3.2.1 Interconnect Cable ............................... 3–6

3.2.2 Power Supply Module ............................ 3–8

3.2.3 Discharging the CRT and Removing the Anode Cap ..... 3–10

3.2.4 Deﬂection Module ............................... 3–12

3.2.5 Video Casting Assembly . . . ........................ 3–16

3.2.6 CRT/Chassis Assembly............................ 3–20

3.3 CRT Disposal (Trained Service Personnel Only) . . . ....... 3–21

3.4 Tilt-Swivel Base . . ................................ 3–24

iii

iv Contents

4 Aligning the Video Monitor

4.1 Introduction ...................................... 4–1

4.1.1 Before You Start . ................................ 4–1

4.1.2 Check LEDs and Heater Filament................... 4–4

4.1.3 Displaying Screen Tests . . . ........................ 4–4

4.2 Monitor Adjustments ............................... 4–5

4.3 Deﬂection Adjustments ............................. 4–6

4.3.1 Raster Adjustment ............................... 4–6

4.3.2 Anode Voltage Adjustment . ........................ 4–6

4.3.3 Height and Width Adjustments ..................... 4–6

4.4 Using the Radiance Meter . . . ........................ 4–8

4.5 Cutoff Adjustment . ................................ 4–10

4.6 GAIN Adjustment . ................................ 4–11

A VR315 and VR325 Documentation

Figures

1–1 Monochrome Monitor ............................... 1–1

3–1 Removing Cables from the Monitor .................... 3–2

3–2 Rear Cover Removal ............................... 3–3

3–3 Top Cover Removal ................................ 3–4

3–4 Field Replaceable Units ............................. 3–5

3–5 Disconnecting the Interconnect Cable . . . ............... 3–7

3–6 Removing the On/Off Switch Cable from the Power Supply . . 3–8

3–7 Removing the Power Supply . ........................ 3–9

3–8 Discharging the CRT and Removing the Anode Cap ....... 3–11

3–9 Loosening the Captive Screw . ........................ 3–13

3–10 Disconnecting Cables from the Deﬂection Module . . ....... 3–14

3–11 Removing the Deﬂection Module ...................... 3–15

3–12 Removing Cables from the Video Casting ............... 3–17

3–13 Removing the CRT Socket Connector ................... 3–18

3–14 Removing the Video Casting . ........................ 3–19

3–15 Crushing the Evacuation Point ....................... 3–23

3–16 Tilt-Swivel Base . . ................................ 3–25

4–1 User Controls and Indicator . . ........................ 4–3

Contents v

4–2 Circle-Crosshatch Pattern . . . ........................ 4–4

4–3 Using the Metric Measuring Tape ..................... 4–5

4–4 Internal Controls . . ................................ 4–7

4–5 Radiance Meter . . . ................................ 4–9

4–6 Using the Radiance Meter . . . ........................ 4–10

4–7 GAIN, G2, and FOCUS (G4) Adjustments .............. 4–11

Tables

1–1 Tools and Equipment ............................... 1–2

1–2 Recommended Spare Parts. . . ........................ 1–3

2–1 Blank Screen, No Video or Raster ..................... 2–3

2–2 Blank Screen, No Video, but Raster is Present ........... 2–5

2–3 Poor Display Quality ............................... 2–6

4–1 Monitor Controls and Indicators ...................... 4–2

AboutThisManual

VR315 and VR325 Video Monitors

This guide describes how to service the VR315 and VR325 monochrome monitors in the ﬁeld.

Manual Organization

This manual is organized as follows:

• 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.

• Appendix A describes related documentation.

Conventions

Convention Meaning

Caution Provides information to prevent damage to the equipment. Warning Provides information that relates to personal safety. Note Provides general information. PN Refers to a part number.

monitor Refers to the VR315 and VR325 monochrome monitors.

This type of number in text refers to an item in an illustration.

vii

Overview

1.1 Product Description

The monochrome monitor (Figure 1–1) has a direct viewed antiglare screen with an auto-ranging power supply for worldwide operation. Its built-in tilt-swivel base lets the user adjust the screen for viewing comfort. When connected to a host system, the monitor displays information sent by the host.

Figure 1–1 Monochrome Monitor

MA-0299-90.DG

1–1

1–2 Overview

1.1.1 Model Variations

The monitor is available in the following models:

Model Applicable Area

VR315-DA Northern hemisphere VR315-D4 Southern hemisphere VR325-DA Northern hemisphere VR325-D4 Southern hemisphere

1.2 Tools and Equipment

Table 1–1 lists the tools and equipment you will need to service the monitor:

Table 1–1 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 List

Table 1–2 lists the recommended spare parts for the monitor.

Table 1–2 Recommended Spare Parts

VR315 Part

Spare Part

Power supply 54-19629-02 54-19629-03 Deﬂection module 54-19826-01 54-19826-02 Video casting assembly 70-27073-01 70-27073-01 Module interconnect cable 70-27000-02 70-27000-02 CRT/chassis assembly

Northern Hemisphere 70-27477-01 70-27481-03 Southern Hemisphere 70-27477-02 70-27481-04

Number

VR325 Part Number

Troubleshooting

This chapter describes how to troubleshoot a 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 off and disconnect the power cord.

• If you are going to service a display quality type of problem, tell the customer to warm the monitor 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.

2–1

2–2 Troubleshooting

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.

Troubleshoot the monitor as follows:

1. Ask the operator to describe the problem. The operator often is the most knowledgeable.

2. Identify the problem. The screen display often indicates which problem is occurring.

3. Isolate the problem. Refer to the troubleshooting tables (Section 2.3) 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 three types of video problems that the monitor may exhibit:

• A blank screen, without video or raster (Table 2–1)

• A blank screen, without video, but raster present (Table 2–2)

• Poor display quality (Table 2–3)

Use the troubleshooting tables as follows:

1. Note the 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.

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 (the power switch is in) but the power indicator light is off.

No video or raster, but the power indicator is on.

The power cord is not connected to the power source or monitor.

Low or no power at wall outlet.

Power supply module is faulty.

Deﬂection module is faulty.

Video module is faulty.

Brightness or contrast is set incorrectly.

Power to the host system is not on.

Host signal cable is disconnected.

Connect the power cord to the power source or monitor.

Use another wall outlet. If the problem continues, call the facilities person.

Replace the power supply module (Section 3.2.2).

Replace the deﬂection module (Section 3.2.4).

Replace the video casting assembly (Section 3.2.5).

Adjust the brightness and contrast controls.

Turn power to the host system on.

Connect the signal cable to the monitor and host.

2–4 Troubleshooting

Table 2–1 (Cont.) Blank Screen, No Video or Raster

Symptom Possible Cause Suggested Solution

No video or raster, but the power indicator and LED on the deﬂection module are on.

No video or raster, but the power indicator LED is on; the deﬂection module LED is off.

Deﬂection module is faulty.

Video casting assembly is faulty.

CRT/chassis assembly is faulty.

Internal cabling is loose or faulty.

G2 Bias is set incorrectly.

Signal cable is faulty.

Deﬂection module is faulty.

Replace the deﬂection module (Section 3.2.4).

Replace the video casting assembly (Section 3.2.5).

Replace the CRT/chassis assembly (Section 3.2.6) only after trying the previous solutions.

Check all cabling going to the deﬂection module and the video casting assembly, including the CRT socket connector. If necessary, secure the cables.

Correct the G2 adjustment. (Section 4.5).

Replace the signal cable. Refer to the host system documentation.

Replace the deﬂection module (Section 3.2.4).

Troubleshooting 2–5

Table 2–2 Blank Screen, No Video, but Raster is Present

Symptom Possible Cause Suggested Solution

Raster can be displayed by adjusting the brightness control, but no video or cursor can be seen even when the contrast control is at maximum.

The Host system CRT screen saver feature is activated.

Internal cabling is loose or faulty.

The host system is not supplying video signals to the monitor.

Host system is faulty.

Video casting assembly is faulty.

Deﬂection module is faulty.

Faulty CRT/chassis assembly

Press any key to reactivate the display.

Check all the cables to the deﬂection module and the video casting assembly.

Connect the monitor to a known working host system (if available) to verify the problem before replacing any monitor modules.

Repair the host system.

Replace the video casting assembly (Section 3.2.5).

Replace the deﬂection module (Section 3.2.4).

Replace the CRT/chassis assembly (Section 3.2.6) only after trying the previous solutions.

2–6 Troubleshooting

NOTE

Make sure the monitor has warmed up for at least 20 minutes before you use Table 2–3.

Table 2–3 Poor Display Quality

Symptom Possible Cause Suggested Solution

Poor geometry, centering, height, width, and/or linearity.

Poor light output (using the all-white diagnostic pattern). The Display is not bright enough.

Controls on top of the monitor are out of adjustment.

Local magnetic ﬁelds. Remove any electro-

Monitor is out of adjustment.

Deﬂection module is faulty.

CRT/chassis assembly is faulty.

The brightness or contrast control is set incorrectly.

Host system is not supplying correct signal levels.

GAIN and Cutoff adjustments may be incorrect.

Video casting assembly is faulty.

Deﬂection module is faulty.

See section 4.1.

mechanical devices from the vicinity of the monitor, or move the monitor to another location.

Perform the alignment procedure. Refer to Chapter

4. Replace the deﬂection module

(Section 3.2.4). Replace the CRT/chassis

assembly (Section 3.2.6) only after trying the previous solutions.

Adjust the brightness and contrast controls.

Repair the host system.

Perform the GAIN adjustment (Section 4.6) and the Cutoff adjustment (Section 4.5).

Replace the video casting assembly (Section 3.2.5).

Replace the deﬂection module (Section 3.2.4).

+ 42 hidden pages

DEC VR315, VR325 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual