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VOFS (Offset voltage) adjustment
Method 1
1. Write down a adjustment value of VOFS ADJ in the factory mode.
2. Set this adjustment value to center (128).
3. Adjust VR2701 so that the voltage between K2701 (VOFS) and K2703 (SUS GND) becomes

45V.

4. Return it to the value that wrote down a adjustment value of V-OFFSET in step 1.

Method 2
1. Read the adjustment value of VOFS ADJ in the factory mode.
2. Adjust VR2701 so that the voltage between K2710 (VOFS) and K2703 (SUS GND) becomes

following voltage 

±

 0.5V.

VH (voltage for scan IC) Adjustment
Adjust so that the voltage between K2716 (VH) and K2720 (PSUS) becomes 103V 

±

 0.5V.

PSUS (=GNDH) is a floating GND and the electric potential is different from that of chassis 
GND. Be sure not to short-circuit PSUS (=GNDH) and another GND, because that may 
damage the unit.

The symptom is case of mis-adjustment
If the VH adjustment is not performed properly, dots like blinking luminance points appear. If 
deviated greatly from the right adjustment point, panel will light white.

White 100%

VR2701 (VOFS)
(Y DRIVE Assy)

VR2703 (VH)
(Y DRIVE Assy)

IC5V Adjustment
Adjust so that the voltage between K2707 (IC5V) and K2720 (PSUS) becomes 5.0V 

±

 0.1V.

PSUS (=GNDH) is a floating GND and the electric potential is different from that of chassis 
GND. Be sure not to short-circuit PSUS (=GNDH) and another GND, because that may 
damage the unit.

The symptom is case of mis-adjustment
If the VOFS Voltage adjustment is not performed properly, dots like blinking luminance points 
appear. If deviated greatly from the right adjustment point, panel will light white.

VR2702 (IC5V)
(Y DRIVE Assy)

Note : Be sure to measure between specified test points.

VOF000

0.4

25

VOF134

2.599212598

45.94488

VOF006

0.4984375

25.9375

VOF141

2.71496063

47.04724

VOF013

0.61328125

27.03125

VOF147

2.814173228

47.99213

VOF019

0.71171875

27.96875

VOF153

2.913385827

48.93701

VOF026

0.8265625

29.0625

VOF160

3.029133858

50.03937

VOF032

0.925

30

VOF166

3.128346457

50.98425

VOF038

1.0234375

30.9375

VOF172

3.227559055

51.92913

VOF045

1.13828125

32.03125

VOF179

3.343307087

53.0315

VOF051

1.23671875

32.96875

VOF185

3.442519685

53.97638

VOF058

1.3515625

34.0625

VOF191

3.541732283

54.92126

VOF064

1.45

35

VOF198

3.657480315

56.02362

VOF070

1.5484375

35.9375

VOF204

3.756692913

56.9685

VOF077

1.66328125

37.03125

VOF211

3.872440945

58.07087

VOF083

1.76171875

37.96875

VOF217

3.971653543

59.01575

VOF090

1.8765625

39.0625

VOF223

4.070866142

59.96063

VOF096

1.975

40

VOF230

4.186614173

61.06299

VOF102

2.0734375

40.9375

VOF236

4.285826772

62.00787

VOF109

2.18828125

42.03125

VOF242

4.38503937

62.95276

VOF115

2.28671875

42.96875

VOF249

4.500787402

64.05512

VOF122

2.4015625

44.0625

VOF255

4.6

65

VOF128

2.5

45

White 100%

REF_DIG mode
in Factory mode

XSUSB ADJ
YSUSB ADJ

X-SUS-B, Y-SUS-B Adjustment
Set to the indicated value with the remote control unit.
(Refer to "Timing adjustment of control signal of X and Y Drive Assys".)

White 100%

VR3701 (VRN)
(X DRIVE Assy)

VRN (minus reset voltage adjustment)
Adjust so that the voltage between K3707 (VRN) and K3702 (SUS-GND) becomes
-300V 

±

 1.0V.

Reference : Adjustment values using the Media color-difference meter (CA-100)

Adjust the parameter in the OFFSET-DIGITAL of factory mode as follows;

PANEL R-HIGH

PANEL B-LOW

In this time, dispay uses the mask (MASK04) of factory mode.

x

295

y

306

291

300

∗

When perform the various adjustment by RS-232C control, execute a "DM0" command (release the limit of pulse number) 
beforehand.
After the adjustment completion, execute a "DM 3" command (Limit of pulse number: 64%, shipping state) by all means.

As for this adjustment, adjustment with set state is difficult.
Therefore replace it every Assy when replacing the pulse module.

Display a SUSOUT waveform

Power ON and display a SUSOUT 
waveform

Display a SUS-D waveform

Display a SUS-U waveform

Power ON and 
display a SUS-D waveform

Display a SUS-U waveform

Measuring points of waveform
are refered to next page.

Power ON
Black Mask Screen

Coarse adjustment of
SUS-U, SUS-B, SUS-G

SUS-D adjustment
Adjust the waveform to 20-25ns.

SUS-U adjustment
Adjust the waveform to 20-25ns.

Power OFF

Compare waveform, 

and do harmonize 

almost?

Yes

No

Adjust VR resistance value
of SUS-B and SUS-G to match
VR resistance value of SUS-D
within 

±

 2

Ω

.

Adjust VR resistance value
of SUS-B and SUS-G to match
VR resistance value of SUS-D
within 

±

 2

Ω

.

Power OFF

Adjustment end

SUS-D readjustment
Adjust the waveform to 20-25ns.

SUS-U readjustment
Adjust the waveform to 20-25ns.

X DRIVE

Y DRIVE

SUS-U

VR3203

VR2204

SUS-D

VR3202

VR2203

SUS-B

VR3201

VR2202

SUS-G

VR3200

VR2201

Pulse Module

X DRIVE

Y DRIVE

Upper

Lower

Upper

Lower

SUSOUT

K3105

K3106

K2212

K2203

SUS-U

K3200

K3204

K2220

K2224

SUS-D

K3108

K3205

K2207

K2225

• Pulse module loads in DRIVE Assy as one of heat measures of DRIVE Assy. Adjust the drive timing of the pulse module 

driving parallel with VR.

• Pulse module has each peculiar delay time. Readjustment is necessary when replaced the pulse module in the X and 

Y DRIVE Assys.

CR delay circuit is each inserted on signal path of four control signals (SUS-U, SUS-B, SUS-D, SUS-G) driving 
the pulse module.
Quantity of delay can adjust pulse module of one side with VR.
Adjust VR while measuring a waveform of the pulse module, and match a timing.

Use this sustain pulse
and adjust.

Magnify 6SF block

Magnify the adjustment waveform

Magnify 6SF block

CH1 : Y SUSOUT Under (K2203), 50V/div
CH2 : Y SUSOUT Upper (K2212), 50V/div
CH4 : YPR-U1 (K2038)- Trigger, 5V/div
Trigger : 2msec delay

CH1 : Y SUSOUT Under (K2203), 50V/div
CH2 : Y SUSOUT Upper (K2212), 50V/div
CH4 : YPR-U1 (K2038)- Trigger, 5V/div
Trigger : 2msec delay

CH1 : X SUSOUT Under (K3106), 50V/div
CH2 : X SUSOUT Upper (K3105), 50V/div
CH4 : YPR-U1 (K2038)- Trigger, 5V/div
Trigger : 2msec delay

Timing adjustment of the pulse module control signal adjusts with the sustain pulse of eighth pulse (X DRIVE) and 
the ninth pulse (Y DRIVE) from the back of 6SF.

µ

µ

• Perform adjustment of waveform with a black mask screen.
• It is easy to adjust when turned field AB offset to OFF (RS-232C
  command: OCN) in adjustment.

Note:
• Sampling rate of oscilloscope sets it more than 500MS/s in order
  to perform ns order adjustment.
• Collecting calibration of probe before adjustment by all means.

• Connect GND of probe measuring waveform to SUSGND terminal
  by all means.
• Precise waveform is not displayed, and an adjustment gap may
  occur that does not collect GND properly.

When took waveform be each drive Assy unit, measure it at the 
fourth sustain pulse from the back except for a large width sustain 
pulse.
Therefore, when measured both waveform of the X and Y drives 
together, it becomes the sustain pulse of 8 and 9 pulses from the 
back.

When there is a gap with waveform of CH1 / CH2 of the part which 
enclosed in the following circle, adjust required VR to overlap the 
waveform.

Adjust with SUS-B

Adjust with SUS-U

Adjust with SUS-G

Use this sustain pulse
and adjust.