NEC AccuSync LCD72VM User Manual page 76

OSM Functions – Warnings
NO SIGNAL
Video Input: No Signal
Warning for factory menu
This function gives a warning when input signal is not
active. After power on or when input signal become
inactive, this warning will appear.
No signal OSD shall be shown after around 0.5sec from
decision of video mode. This OSD shall be turned off after
5 seconds automatically. Then go to power saving mode.
"No Signal" OSD Shall be displayed in the center of
screen.
This is right.
Because this warning message is for user. We urge to
no enter to service menu.
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