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– 13 –

20

If there is something wrong with the input signal, one of the
following messages appears.

1 The input signal condition

“OUT OF SCAN RANGE” indicates that the input signal
is not supported by the monitor’s specifications.

“NO INPUT SIGNAL” indicates that no signal is input, or
the input signal from the selected input connector is not
received.

2 The selected input connector

Indicates which input connector is receiving the wrong
signal. If there is something wrong with the signal from
both input connectors, “HD15” and “BNC” are
displayed alternately.

To solve these problems, see “Troubleshooting” below.

This section may help you isolate the cause of a problem and as a result, eliminate the need to contact technical support.

If the u indicator  is not lit

If the “NO INPUT SIGNAL”
message appears on the screen,
or if the u indicator is either
orange or alternating between
green and orange

If the “OUT OF SCAN RANGE”
message appears on the screen

If no message is displayed and
the u indicator is green or
flashing orange

If using a Macintosh system

If using Windows



 95

• Check that the power cord is properly connected.
• Check that the u (power) switch is in the “on” position.

• The screen is blank when the monitor is in power saving mode. Try pressing any key on the

computer keyboard.

• Check that your computer power switch is in the “on” position.
• Check that the input select setting is correct.
• Check that the video signal cable is properly connected and all plugs are firmly seated in

their sockets.

• Check that the 5 BNCs are connected in the correct order (from left to right: Red–Green–

Blue–HD–VD) (page 6).

• Ensure that no pins are bent or pushed in the HD15 video input connector.
• Check that the video board is completely seated in the proper bus slot.

• Check that the video frequency range is within that specified for the monitor.

Horizontal: 30 – 94 kHz (GDM-400PS), 30 – 107 kHz (GDM-500PS)
Vertical: 48 – 160 Hz
Refer to your computer’s instruction manual to adjust the video frequency range.

• If you are using a video signal cable adapter, check that it is correct.

• See “Self-diagnosis Function” (page 22).

• Check that the Macintosh adapter and the video signal cable are properly connected (page

6).

• If you cannot find your model’s name (GDM-400PS or GDM-500PS) among the Sony

monitors in the Windows 95 monitor selection screen, select the DDC standard monitor or
install the Windows 95 Monitor Information Disk (page 7).
The DDC standard does not apply to the 5 BNC connectors. If you use the DDC standard,
connect the computer to the HD15 connector with the supplied video signal cable.

• Check your graphics board manual for the proper monitor setting.
• Check this manual and confirm that the graphics mode and the frequency you are trying to

operate at is supported. Even if the frequency is within the proper range, some video
boards may have a sync pulse that is too narrow for the monitor to sync correctly.

    INFORMATION

OUT  OF  SCAN  RANGE

INPUT : HD15

21

• Degauss the monitor (page 15).

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.

• Adjust the landing (pages 13 – 14).

• If the control lock function is set to on, set it to off using the OPTION OSD (page 16).

• Adjust the color temperature (pages 12 – 13).
• Check that the 5 BNCs are connected in the correct order (from left to right: Red–Green–

Blue–HD–VD) (page 6).

• Press the ASC button (page 7).
• Adjust the size or centering (page 10).
• Some video modes do not fill the screen to the edges. This problem tends to occur with

certain video boards.

• Adjust the geometry (page 11).

• Adjust the convergence (pages 13 – 14).

• Adjust the contrast and brightness (page 9).
• Degauss the monitor (page 15).

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 13 – 14).

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

effect (pages 13 – 14).

• 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 13 – 14).

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 19). 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.

– 14 –

     Seven screws
     (+BVTT 3 x 8)

4

     Two screw covers
     (L and R)

1

     Side cover

7

     Video shield

9

     Cabinet

3

     Four screws
     (+BVTP 4 x 16)

2

     Four screws
     (+BVTT 3 x 8)

6

     Screw
     (+BVTT 3 x 8)

8

     EMI shield

5

CN406
CN405

CN404
CN403
CN401
CN402

     A board

2

     Three screws
     (+BVTT 3 x 8)

1

– 15 –

CN404

CN403

CN601

     AC inlet (3P)

6

     Two screws
     (Ext tooth washer screw M4)

2

     Three screws
     (+BVTT 3 x 8)

7

     Two screws
     (+KTP 3 x 8)

5

     Rear shield

3

     I/O terminal board

8

     Screw
     (Ext tooth washer screw M4)

4

     A board

1

GND

GND

Connector (9pin)

GND

CN406
CN405

CN602

     Shield (D)

2

     D board

5

     Three screws
     (+BVTP 3 x 10)

3

     Screw
     (+BVTT 4 x 8)

1

     Printed circuit
     board holder

4

– 16 –

CN601

D board

AC inlet (3P)

Four screws

  Tapping screw 5: U/C model

  Self tapping screw 5: AEP, UK model

CN801

H board

Two screws

(+ BVTP 4 x 16)

Bezel

2

Two printed circuit board stoppers

4

3

Claw

5

1

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