VarTech Systems GDM-5001PT Service Manual Download Page 13

Page: 13 / 53

1-8

Getting Started

Additional Information

Symptom

Check these items

You cannot adjust the monitor
with the buttons on the front
panel

White does not look white

Screen image is not centered or
sized properly

Edges of the image are curved

White lines show red or blue
shadows at edges

Picture is fuzzy

Picture bounces or has wavy
oscillations

Picture is flickering

Picture appears to be ghosting

Wavy or elliptical (moire)
pattern is visible

Two fine horizontal lines
(wires) are visible

Hum is heard right after the
power is turned on

• If the control lock function is set to on, set it to off using the OPTION OSD (page 15).

• Adjust the color temperature (pages 11 – 12).
• Check that the 5 BNCs are connected in the correct order (from left to right: Red–Green–

Blue–HD–VD).

• Press the

button (page 6).

• Adjust the size or centering (page 9).
• Some video modes do not fill the screen to the edges. This problem tends to occur with

certain video boards.

• Adjust the geometry (page 10).

• Adjust the convergence (pages 12 – 13).

• Adjust the contrast and brightness (page 8).
• Degauss the monitor (page 14).

If you place equipment which generates a magnetic field, such as a loudspeaker, near the
monitor, or you change the direction of the monitor, color may lose uniformity.
The degauss function demagnetizes the metal frame of the CRT to obtain a neutral field for
uniform color reproduction. If a second degauss cycle is needed, allow a minimum interval
of 20 minutes for the best result.

• If red or blue shadows appear along the edges of images, adjust the convergence

(pages 12 – 13).

• If the moire is cancelled, the picture may become fuzzy. Decrease the moire cancellation

effect (pages 12 – 13).

• Isolate and eliminate any potential sources of electric or magnetic fields. Common causes

for this symptom are electric fans, fluorescent lighting or laser printers.

• If you have another monitor close to this monitor, increase the distance between them to

reduce the interference.

• Try plugging the monitor into a different AC outlet, preferably on a different circuit.
• Try the monitor on a different computer in a different room.

• Set the refresh rate on the computer to obtain the best possible picture by referring to the

computer’s manual.

• Eliminate the use of video cable extensions and/or video switch boxes if this symptom

occurs. Excessive cable length or a weak connection can produce this symptom.

• Cancel the moire (pages 12 – 13).

The moire may be modified depending on the connected computer.

• Due to the relationship between resolution, monitor dot pitch and the pitch of some image

patterns, certain screen backgrounds sometimes show moire. Change your desktop pattern.

• These wires stabilize the vertically striped aperture grille (page 17). This aperture grille

allows more light to pass through to the screen giving the Trinitron CRT more color and
brightness.

• When the power is turned on, the auto-degauss cycle is activated. While the auto-degauss

cycle is activated (3 seconds), a hum may be heard. The same hum is heard when the
monitor is manually degaussed. This is not a malfunction.

Additional Information

Self-diagnosis Function

This monitor is equipped with a self-diagnosis function. If
there is a problem with your monitor or computer(s), the
screen will go blank and the

indicator will either light up

green or flash orange.

If the

indicator is green

Remove any plugs from the video input 1 and 2
connectors, or turn off the connected computer(s).

Press and hold the

button for 2 seconds.

If all four color bars appear (white, red, green, blue), the
monitor is working properly. Reconnect the video input
cables and check the condition of your computer(s).

If the color bars do not appear, there is a potential
monitor failure. Inform your service representative of
the monitor’s condition.

If the

indicator is flashing orange

Press the

button to turn the monitor off and on.

If the

indicator lights up green, the monitor is

working properly.

If the

indicator is still flashing, there is a potential

monitor failure. Count the number of seconds between
orange flashes of the

indicator and inform your

service representative of the monitor’s condition. Be sure
to note the model name and serial number of your
monitor. Also note the make and model of your
computer and video board.

indicator

Specifications

Picture tube

0.25 – 0.27 mm aperture grille pitch
21 inches measured diagonally
90-degree deflection

Viewable image size

Approx. 403.8

302.2 mm (w/h)

(16

inches)

19.8” viewing image

Resolution

Horizontal: Max. 1600 dots
Vertical: Max. 1200 lines