Applica RV500C : Technical information : Page 193

2.6.2.2 Pattern Checks

These symptoms relate to operating the display with a crosshatch pattern

displayed. Pattern checks must be done using pattern A on the IBM

Personal System/2 Color Displays Test-Pattern Diskette.

Before starting any checks, ensure that all plugs and connectors are

positioned correctly and securely.

Refer to "Adjustment Procedures" in topic 2.6.2.3 when adjustments are

required.

Refer to the "Display-Specific Removals and Replacements" in topic 2.6.1

for removal and replacement procedures.

+------------------------------------------------------------------------+

¦ Symptom ¦ Action ¦

+-----------------------+------------------------------------------------¦

¦ Displayed image width ¦ Adjust RT7 for modes 1 through 3, RT8 for mode ¦

¦ is too large or too ¦ 4. If symptom persists, replace card tray ¦

¦ small. ¦ assembly. ¦

+-----------------------+------------------------------------------------¦

¦ Displayed image ¦ Adjust RT6. If symptom persists, replace card ¦

¦ height is too large ¦ tray assembly. ¦

¦ or too small. ¦ ¦

+-----------------------+------------------------------------------------¦

¦ Color purity of ¦ Check degauss circuit. Ensure that Q2 is ¦

¦ displayed image is ¦ connected. Power off for 30 minutes. Power ¦

¦ poor. ¦ on again to check degauss action. If symptom ¦

¦ ¦ persists, replace card tray assembly. ¦

¦ ¦ ¦

¦ ¦ ITC defective. Replace ITC. ¦

+-----------------------+------------------------------------------------¦

¦ Contrast or ¦ Replace card tray assembly. ¦

¦ brightness controls ¦ ¦

¦ are not working. ¦ ¦

+-----------------------+------------------------------------------------¦

¦ Maximum or minimum ¦ Adjust video color point as appropriate. ¦

¦ white is poor. ¦ ¦

+-----------------------+------------------------------------------------¦

¦ East-west pincushion ¦ Adjust RT14, RT11, and RT12 for optimum ¦

¦ correction is poor ¦ vertical lines. If this is not possible, ¦

¦ (vertical lines are ¦ replace the card tray assembly. ¦

¦ bowed or barrel ¦ ¦

¦ shaped). ¦ ¦

+-----------------------+------------------------------------------------¦

¦ No horizontal or ¦ If good with test raster (signal cable ¦

¦ vertical ¦ disconnected), replace signal cable. ¦

¦ synchronization. ¦ ¦

¦ ¦ ¦

¦ One or more colors ¦ ¦

¦ missing. ¦ ¦

+-----------------------+------------------------------------------------¦

¦ Displayed image does ¦ Ensure that Q1 and Q4 are connected. If ¦

¦ not synchronize ¦ symptom persists, replace card tray assembly. ¦

¦ horizontally. ¦ ¦

+-----------------------+------------------------------------------------¦

¦ Displayed image does ¦ Ensure that Q1 and Q4 are connected. If ¦

¦ not synchronize ¦ symptom persists, replace card tray assembly. ¦

¦ vertically. ¦ ¦

+-----------------------+------------------------------------------------¦

¦ Background raster is ¦ Adjust RT15. If raster cannot be centered, ¦

¦ not centered ¦ centering circuit is faulty. Replace card ¦

¦ horizontally. ¦ tray assembly. ¦

+-----------------------+------------------------------------------------¦

¦ Displayed image is ¦ Adjust RT3 for modes 1 through 3, RT2 for mode ¦

¦ not centered ¦ 4. If image cannot be centered, centering ¦

¦ horizontally. ¦ circuit is faulty. Replace card tray ¦

¦ ¦ assembly. ¦

+-----------------------+------------------------------------------------¦

¦ Displayed image ¦ Height selection circuit is faulty. Replace ¦

¦ height varies ¦ card tray assembly. ¦

¦ excessively between ¦ ¦

¦ modes. ¦ ¦

+-----------------------+------------------------------------------------¦

¦ Displayed image ¦ Width regulation is unstable. Ensure that Q1 ¦

¦ appears broken up ¦ and Q4 are connected. If symptom persists, ¦

¦ horizontally. ¦ replace card tray assembly. ¦

+------------------------------------------------------------------------+

PS/2 Displays Maintenance Manual

Pattern Checks

2.6.2.2 - 1