VarTech Systems VT121 DiamondVue Series, User Manual

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13
Image position:
If it is impossible to position the image correctly, ie the image adjustment controls will not move the
image far enough, then test using another graphics card. This situation can occur with a custom
graphics card that is not close to standard timings or if something is in the graphics line that may be
affecting the signal such as a signal splitter (please note that normally a signal splitter will not have
any adverse effect).
Image appearance:
A faulty panel can have blank lines, failed sections, flickering or flashing
display, incorrect graphics card refresh rate, resolution or interlaced
mode will probably cause the image to be the wrong size, to scroll,
flicker badly or possibly even no image. Incorrect jumper settings on the
controller may cause everything from total failure to incorrect image.
CAUTION: Do not set the panel power input incorrectly. Sparkling on the
display: faulty panel signal cable.
Backlight:
Items to check include: Power input, Controls, Inverter and Tubes generally in this order. If half the
screen is dimmer than the other half: Check cabling for the inverter. For a specific backlight tube
check the AC pins orientation (CAUTION: Never reverse any DC power pins). Also: If adjusting
brightness control has no effect the chances are that the VR rating or method of adjusting brightness
is not compatible or correctly connected to the inverter. If system does not power down when there
is a loss of signal
Continued failure:
If unit after unit keeps failing consider and investigate whether you are short circuiting the
equipment or doing something else seriously wrong.
Generally after common sense issues have been resolved we recommend step by step
substitution of known working parts to isolate the problem.
SECTION 6
6.1
Cleaning
Occasionally clean the display panel and cabinet with a soft cloth dampened (not soaked) with a mild
(non-abrasive) glass cleaner. Keep turning a fresh side of the cloth toward the screen surface to
avoid scratching it with accumulated grit.
Note:
The solvent should be applied only to the cloth, and not directly on the monitor screen.