NEC FE791SB Computer Monitor User Manual


 
1-39
MultiSync FE791
SB
/ FE991
SB
15
Troubleshooting
No picture
Display card should be completely seated in its slot.
Power Button and computer power switch should be in the ON position.
Signal cable should be completely connected to display card/computer.
Check connector for bent or pushed-in pins.
Image is scrolling or unstable
Signal cable should be completely attached to the computer.
Check pin assignments and signal timings of the monitor and your display card with respect to
recommended timings and pin assignments.
If the Macintosh cable adapter is used, check for proper connection or make sure the display card is
Macintosh compatible and that the card is properly seated in the computer.
LED on monitor is not lit (no green, orange colour can be seen)
Power Switch should be in the ON position and power cord should be connected.
Picture is fuzzy or colour looks blotchy
Adjust Brightness and Contrast Controls or adjust the Moiré Canceler control.
Access the Degauss Control through OSM controls. Activate the Degauss Control.
CAUTION: A minimum interval of 20 minutes should elapse before the Deguass Control is used a second
time when not switching between modes.
Picture bounces or a wavy pattern is present in the picture
Move electrical devices that may be causing electrical interference away from the monitor.
See inside cover of User’s Manual for FCC information.
Edges of the display image are not square
Use the OSM Geometry Controls to straighten the edges.
If possible, position the front of the monitor facing east.
Display image is not centered, too small, or too large
Use the OSM Size and Position Controls to adjust the image.
Thin lines appear on your screen
Thin lines are normal for an aperture grille CRT and are not a malfunction.
These are shadows from the damper wires used to stabilize the aperture grille and are most noticeable when
the screen’s background is light (usually white).
Black vertical lines are visible on the screen
Thin vertical black lines on one or both sides of the screen. This minor condition is caused by grille element
overlap which can occur during shipping.
Position an open white window over the affected area of the screen and maximize the brightness and
contrast controls. This will cause localized heating of the overlap which will clear in a few minutes. Be sure
to readjust the brightness and contrast controls back to the normal viewing level after this procedure.