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1

US Model

Canadian Model

AEP Model

UK Model

E Model

Subject : Addition of Electrical Adjustments.

Addition of Block Diagrams.
Addition of IC Block Diagrams.

1-1. Equipment Used ................................................................. 2
1-2. Connection of Equipment .................................................. 2
1-3. 5V Adjustment ................................................................... 2
1-4. Frequency Adjustment ....................................................... 2
1-5. PLL Free Run Frequency Adjustment ............................... 2
1-6. Brightness Temporary Level Adjustment ........................... 3
1-7. Sharpness Adjustment ........................................................ 3
1-8. Contrast Adjustment ........................................................... 3
1-9. Color Adjustment ............................................................... 3
1-10. Hue Adjustment ................................................................. 3
1-11.

γ 2 Adjustment .................................................................... 3

1-12.

γ 0 Adjustment .................................................................... 3

1-13. RGB Gain (1) Adjustment ................................................. 3
1-14. RGB Gain (2) Adjustment ................................................. 3
1-15. B and R Level Adjustments ................................................ 3
1-16. VCOM AMP Adjustment ................................................... 3
1-17. VCOM Bias Adjustment .................................................... 4
1-18. Blank Level Adjustment ..................................................... 4
2-1. Block Diagram –Main Section– ......................................... 5
2-2. Block Diagram –B/L (Display) Section– ........................... 6
2-3. Block Diagram –RGB (Display) Section– ......................... 7
2-4. Block Diagram –LCD (Display) Section– ......................... 8
2-5. IC Block Diagrams ............................................................ 9

2

When measuring, the ground should be connected to the ground (pin 15 of connector B1) in the display board unless otherwise specified.

The following measuring equipment are used for these electrical adjustments:
• Oscilloscope
• NTSC pattern generator
• Stabilized power supply
• Digital voltmeter
• Frequency counter
• Connection box (XA-117)

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to the C10 position of L19.
3. Adjust VR1 so that the reading on the voltmeter stands at the specified value.

Specified value: 5.00 ± 0.05 V

This frequency adjustment on the DC-DC converter is only performed if there is switching noise mixed on the screen.

Adjust RV20 to a position in which no noise appears on the screen.

1.  Make the input signal no signal.
2.  Connect frequency counter to pin th of IC U705.
3.  Adjust the semi-fixed resistor VFRER until the frequency is at 15895 ± 20 Hz.

VIDEO IN

VIDEO

G
N
D

B+

pattern generator

connection box

XA-117

monitor

XVM-R75

stabilized

power supply

14.4V

3

1. Display gray scale on the monitor screen.
2. Connect digital multimeter to pin wl of IC U600.
3. Adjust the semi-fixed VBRI so that the reading on the digital

voltmeter stands at the specified value.

Specified value: 2.06 ± 0.04 V

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to pin rk of IC U600.
3. Adjust the semi-fixed VPIC so that the reading on the voltmeter

stands at the specified value.

Specified value: 2.59 ± 0.04 V

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to pin 2 of IC U600.
3. Adjust the semi-fixed VCNT so that the reading on the voltmeter

stands at the specified value.

Specified value: 1.25 ± 0.04 V

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to pin 6 of IC U600.
3. Adjust the semi-fixed VCOL so that the reading on the voltmeter

stands at the specified value.

Specified value: 2.58 ± 0.04 V

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to pin qd of IC U600.
3. Adjust the semi-fixed VTIN so that the reading on the voltmeter

is at 3.18 ± 0.04 V.

γ

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to pin wh of IC U600.
3. Adjust the semi-fixed resistor VGA2 so that the reading on the

voltmeter is at 2.43 ± 0.04 V.

γ

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to pin wj of IC U600.
3. Adjust the semi-fixed resistor VGA1 so that the reading on the

voltmeter is at 1.40 ± 0.04 V.

1. Display gray scale on the monitor screen.
2. Connect digital voltmeter to pin wk of IC U600.
3. Adjust VRGB so that the reading on the voltmeter is at 2.05 ±

0.04 V.

1. Display 5-step gray scale on the monitor screen.
2. Connect oscilloscope to pin wa of IC U600.
3. Adjust the semi-fixed resistor VRGB so that the level of the signal

on the fifth step from the above stands at the specified value A.

Specified value A: 0.58 ± 0.04 V

4. Adjust the semi-fixed VGA1 so that the level of the signal on the

first step from the above stands at the specified value B.

Specified value B: 3.25 ± 0.04 V

5. Adjust the semi-fixed VBRI so that the level of the signal on the

fourth step from the above stands at the specified value C.

Specified value C: 1.47 ± 0.04 V

6. Repeat items 3 to 5 and adjust the levels of the signals on the

fifth, first and fourth steps to their specified values.

1. Display 5-step gray scale on the monitor screen.
2. Connect oscilloscope to pin wa specified as G_OUT of IC U600.
3. Measure the black-to-black level.
4. Connect oscilloscope to pin wf specified as B_OUT of IC U600.
5. Adjust VSUB so that the back-to-black level is equal to the level

measured in item 3.

6. Connect oscilloscope to pin ql specified as R_OUT of IC U600.

7. Adjust the semi-fixed resistor VSUR so that the back-to-black

level is equal to the level measured in item 3.

1. Display gray scale on the monitor screen.
2. Connect oscilloscope to the Q701 emitter.
3. Adjust the semi-fixed resistor VCOM until the level A of the

output waveform stand at the specified value.

Specified value: 7.0 ± 0.04 V

GND level

A

C

B

black-to-black level

A

4

1. Display gray scale on the monitor screen.
2. Connect oscilloscope to the Q15 No. 2.
3. Adjust the semi-fixed resistor VCDC until the levels A and B of

the output waveform stand at their respective specified values.

Specified value: A: 5.3 ± 0.04 V

B: 1.7 ± 0.04 V

1. Display gray scale on the monitor screen.  Set the screen to the

Normal mode.

 – DISPLAY BOARD – (CONDUCTOR SIDE)

C10

VR18

VR19

VR20

U705

Q15

Q701

VCDC

VCOM

VSUR

VRGB

VSUB

VBRI

U600

VLOW

VHIG

VCOL

VPIC

VTIN

VGA2

VGA1

VCNT

VFRER

L19

VR1

If not black on the right and left ends,
adjust VHIG and VLOW so that black
vertical bands appear on the right and
left ends of the screen.

2. Connect digital voltmeter to pin 8 of IC U602.
3. Adjust the semi-fixed resistor VHIG so that the reading on the

digital voltmeter is at less than 0.5 V.

4. Connect digital voltmeter to pin 2 of IC U602.
5. Adjust the semi-fixed resistor VLOW so that the reading on the

digital voltmeter is at more than 6.0 V.

A

GND level

B