Notes on the Troubleshooting and Repair of Computer and Video Monitors

Summary

Notes on the Troubleshooting and Repair of Computer and Video Monitors Version 3.22 (5-Dec-09) Reproduction of this document in whole or in part is permitted if both of the following conditions are satisfied: This notice is included in its entirety at the beginning. There is no charge except to cover the costs of copying. Table of Contents Preface Introduction Monitors 101 CRT Basics Monitor Placement and Preventive Maintenance Monitor Troubleshooting Monitor Adjustments Low Voltage Power Supply Problems Deflection Problems High Voltage Power Supply Problems Raster, Color, and Video Problems Blank picture, power light on, digital controls (if any) active Brightness control has no effect No color - black and white picture One color is too weak or too strong Psychodelic color Monitor manufacturing quality and cold solder joints Why can't monitor manufacturers learn to solder properly? Intermittent, flickering, or missing colors Some commentary on monitor and TV whacking Ghosts, shadows, or streaks in picture adjacent to vertical edges General streaks or lines to the right of bright or dark areas Washed out picture Retrace lines in picture White/gray retrace lines Red, green, or blue retrace lines Bad CRT causing retrace lines Red, green, or blue full on - fog over picture Totally white screen (probably with retrace lines) Shorts in a CRT Providing isolation for a CRT H-K short Rescuing a shorted CRT High voltage to focus short Dark picture Brightening an old CRT Color balance changes across screen from left to right Bleeding highlights Trailing lines in one or more colors Purity problems with bright pictures Why does the intensity appear so non-uniform in bright areas? Brightness changes from left-to-right across screen Picture fades in and out Occasional brightness flashes Occasional static, lines, spots, or other unsightly blemishes Flickering monitor Excessive brightness and/or washed out picture Focus problems Bad focus (fuzzy picture) Focus drift with warmup Abou...