Editing VT100 CRT Alignment Guide (section)

== Faults that adjustment will not cure ==
{| class="wikitable styled-table" style="width:100%; text-align:left;"
|+ '''Display faults needing parts'''
! Symptom !! Cause !! Source
|-
| Display bows in or out at the edges || Yoke pincushion misadjusted; DEC replaces the CRT and yoke assembly || DEC Table 5-3<ref name="tm51" />
|-
| Characters narrow on the left or right || Monitor board, flyback transformer, CRT and yoke, or controller || DEC Table 5-3<ref name="tm51" />
|-
| Horizontal line only || Vertical oscillator failed || DEC section 5.6.4<ref name="tm578" />
|-
| Blank white raster, ballooned display || C439 and CR408 (Elston and DEC boards) || Randy Hick, community<ref name="hick" />
|-
| Narrow screen || L402 || Randy Hick, community<ref name="hick" />
|-
| Very wide characters || CR409 || Randy Hick, community<ref name="hick" />
|-
| Overlap in the centre, narrow right side || C437 || Randy Hick, community<ref name="hick" />
|}
See [[VT100 Troubleshooting Guide]] for the rest of DEC's symptom table.