Apple Macintosh Performa 577 - Manual (Page 24)

Troubleshooting Symptom Charts/Video
(Continued)
- 7
Video
(Continued)
Raster tilted or
shifted
1 Verify that adjacent computer equipment is properly
grounded. Move electrical devices away from monitor.
Temporarily shut off all fluorescent lights in area.
2 Perform appropriate geometric adjustments in Adjustments
chapter.
3 Perform yoke adjustment. Refer to “Yoke” in Adjustments
chapter.
4 Replace analog board.
Raster distorted
(barrel-shaped,
corners not square,
stretched or
compressed at top of
display, or sides not
perpendicular)
1 Verify that adjacent computer equipment is properly
grounded. Move electrical devices away from monitor.
Temporarily shut off all fluorescent lights in area.
2 Perform appropriate geometric adjustments in Adjustments
chapter.
3 Replace analog board.
4 Replace CRT (only in rare instances).