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2-7

CN402

CN405

CN407

CN408

CN403

CN406

A board

I/O terminal board assy

Rear shield

CN3002

CN3001

CN3003

S board

CN509

CN506

CN502

CN505

CN504

CN501

CN508

FBT

D board

CN5001

CN5003

CN5002

CN002

CN003

CN001

CN007

CN011

CN010

N board

CN601

CN603

CN602

CN651

G board

AC inlet

CN650

CN652

CN655

CN653

CN654

4pin

4pin

CN2601

US board

CN801

CN802

CN891

Picture tube

J board

H board

H2 board

HV Regulator
Circuit Check

HV Protector
Circuit Check

Beam Current
Protector Circuit
Check

When replacing or repairing the shown below table, the

following operational checks must be performed as a

safety precaution against X-rays emissions from the unit.

3-1

Part Replaced (

[)

RV901

HV ADJ

*

Confirm one minute after turning on the power.

1) Enter black crosshatch signal (black on white back-

ground), and check that high voltage is in the speci-

fied range.

[Specification]: 28.50 ± 0.10 kV

2) Check that the voltage of D912 cathode on the D

board is 29.0 V or more.

1) Enter black crosshatch signal (black on white back-

ground).

2) Apply the specified voltage to the D912 cathode on

the D board, and check that high voltage is 0.1 kV or

less.

[Specification]: 34.00 + 0.00/– 0.05 V

1) Apply 4.5 V DC to CN504 0 pin on the D board,

and check high voltage value.

2) Connect constant current source to a section between

T902 (FBT) qa pin and qs pin (GND) on the D board,

and check that high voltage checked in 1) lowers by

1.50 kV or more when the specified current flows to

the qa pin.

[Specification]: 2.00 + 0.00/– 0.01 mA

1) Connect constant current source to a section between

T902 (FBT) qa pin and qs pin (GND) on the D board,

and check that the voltage of CN504 0 pin becomes

0 V or less when the specified current flows to the qa

pin.

[Specification]: 1.63 + 0.00/– 0.01 mA

1) Apply 264 V AC.

2) Enter about 5 V to CN650 4 pin on the G board, and

check that the output voltage of CN653 2 pin is

about 15 V.

3) Enter about 0 ± 0.2 V to CN650 4 pin, and check

that the output voltage of CN653 2 pin becomes 1.0

V or less.

1) Check that the protector operates, when the voltage

of CN010 qh pin on the N board is lowered to 0 V or

less (for more than 2 seconds).

Part Replaced (

])

D Board IC901, R923, R924,

R929, R943, T902(FBT)
• Mounted D Board

D Board C922, C926, D912,

D915, D921, Q907,
Q908, R921, R922,
R932, R937, R939,
T902(FBT)
• Mounted D Board

D Board C921, C933, D901,

D913, R920, R928,
R930, R931, T902(FBT)
• Mounted D Board

N Board IC001, R031, R032

• Mounted N Board

•

1. Enter the full white signal. (or the full black dots signal).
2. Adjust the contrast to the maximum.
3. Make the screen monogreen.
Note: Off the outputs from R ch and B ch of SG.
4. Reverse the DY, and adjust coarsely the purity magnet so

that a green raster positions in the center of screen.

5. Adjust the tilt of DY, and fix lightly with a clamp.
Note: “TILT” = “128”.

•

1. Put the set inside the Helmholtz coil. (“LCC SW” = “12”)
2. Input the single green signal and set the “CONTRAST” =

“255”.

Note: After the W/B adjustment with 9300K, measure an aver-

age of 

Σ

Ik when a full white signal is entered in the CONT

MAX/BRT CENT status. Then make adjustment so that
the specified screen can be attained after aging for 2 hours
with Ik equivalent to 30% of the average value.

3. Demagnetize the metal part of the chassis with the hand de-

gausser and coil degausser, and the CRT surface with the
hand degausser.
Input AC 230V to AC IN, turn on and off the power to per-
form auto degaussing. (Perform auto degaussing by setting
“FUNCTION SW” = 1. Return to the original value after
use.)
Demagnetize the CRT surface with the hand degausser
again.

Note:
(1) Hand degauss must be used on stand-by or power-off condi-

tion.
This model has an automatic earth magnetism correction
function by using an earth magnetism sensor and a LCC coil.
When using a hand degauss while monitor (LCC coil) is be-
ing operated, it sometimes gets magnetized, and the system
may not work properly as a result.

(2) Adjust in a non-magnetic field.
(3) If adjusting in a magnetic fields, add the shift from the non-

magnetic field in your estimation.

4. Attach the wobbling coil to the designated part of the CRT

neck.

5. Attach the sensor of the landing adjustment unit on the CRT

surface.

6. Adjust the DY position and purity, and the DY tilt, and land-

ing of the center and 4 corners with the landing checker.
After adjustment, set “LCC SW” to “13”.

 ± 6

 ± 6

 ± 6

 ± 6

 ± 6

 ± 6

 ± 6

 ± 6

 ± 6

<Specifications>
Adjust so that the green is within
the specification given right.
4 corner adjust target : within ± 1

The red and blue must be within
the specification given right with
respect to the green.

A difference between red and blue
must be within the specification
given right.

0 ± 3 0 ± 7.5 0 ± 3

0 ± 3 0 ± 7.5 0 ± 3

0 ± 3 0 ± 7.5 0 ± 3

(µm)

(µm)

10

10

10

10

7

10

10

10

10

(µm)

* Adjustment and measurement should be made at the points

one inch inside the fluorescent screen.

7. Tighten DY screw.
Note: Torque 22 ± 2 kg.cm (2.2 ± 0.2 Nm) auto degauss it.
8. For the up/down swing, swing the DY and insert a wedge so

that the up and down pins are equal at the top and bottom.
Adjust the H.TRP VR of DY so that the horizontal trapezoid
is equal at the left and right. Insert the wedge firmly so that
the DY does not shake.

9. Check the landing of each corner, and if it does not satisfy

the specification, adjust the landing of four corners using
“LCC LT“, “LCC LB”, “LCC RT” and “LCC RB”.
However, the register adjustment must be limited within the
following range.

“LCC NS”

128 ± 15

“LCC LT”, “LCC LB”, “LCC RT”, “LCC RB”

128 ± 45

After adjustment, save the service data.

10. Remove the sensor and wobbling coil.
11. Switch the signal to R.G.B., and check that each color is

pure.

12. Check that the DY is not tilting, and fix the purity Mg with a

white pen.  Fix wedges with RTV.

4-1

•

Write terrestrial magnetism sensor reading VX and VY to
“LCC VX” and LCC VY” respectively. Adjust the land-
ing by moving “LCC NS”, “LCC LT”, “LCC LB”, “LCC
RT” and “LCC RB”. However, the register adjustment
must be limited within the following range.
“LCC NS”

128 ± 45

“LCC LT”, “LCC LB”, “LCC RT”, “LCC RB”

128 ± 40

Save the service data.

4-2

Connect the communication cable of the computer to the connector located on the D board. Run the service software and then follow
the instruction.

IBM AT Computer

as a Jig

*The parts above (

1

 and 

2

) are necessary for DAS adjustment.

To BUS CONNECTOR

1-690-391-21
Cord,Connection

D-sub
(9 pin [female])

mini Din
(8 pin)

1

A-1500-819-A
Interface Unit

2

Connector
Attachment

Box Unit

4 pin

•

(1) Receive an image of the white crosshatch signals (white

lines on black).

(2) Place the protrusions of the 6-fold poles magnet attached to

the CRT neck upon each other.

(3) Make rough adjustment of the H and V direction conver-

gence by using 4-fold poles magnet.

•

1. 9300K

x = 0.283 ± 0.015
y = 0.298 ± 0.015

(All White)

2. 6500K

x = 0.313 ± 0.015
y = 0.329 ± 0.015

(All White)

3. 5000K

x = 0.346 ± 0.015
y = 0.359 ± 0.015

(All White)

•

•

Adjust the focus volume 1 and 2 for the optimum focus.

•

B

a

a     3.5 mm
b     3.5 mm

a

b

b

A

MODE

A

B

16 : 9

474

474

16 : 10

266

296

MODE

A

B

4 : 3

395

296

5 : 4

370

296

B

C

A

A

0.24 mm

70kHz

70kHz >

0.24 mm

B

0.24 mm

C

0.28 mm

0.28 mm

0.32 mm

V

fH

* Set so that the protruding parts of

the 2 magnet rings agree with
each other.

XBV

XCV

B

R

B

R

R
B

B
R

R

B

B

R 

TLV

TLH

YBH

YCH

R B

R B

H-TRP

YBH

TLH

TLV

APH

XBV

YCH

XCV

Purity

4-pole magnet

6-pole magnet

2-pole magnet

Focus 1

Focus 2

FBT