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– 17 –

3

When one side of the rubber cap is
separated from the anode button, the
anode-cap can be removed by turning
up the rubber cap and pulling up it in the
direction of the arrow 

c

.

1

Don’t hurt the surface of anode-caps with shartp shaped material!

2

Don’t press the rubber hardly not to hurt inside of anode-caps!
A material fitting called as shatter-hook terminal is built in the
rubber.

3

Don’t turn the foot of rubber over hardly!
The shatter-hook terminal will stick out or hurt the rubber.

NOTE: Short circuit the anode of the picture tube and the anode cap to the metal chassis, CRT shield or carbon painted on the CRT, after

removing the anode.

1

Turn up one side of the rubber cap in
the direction indicated by the arrow 

a

.

2

Using a thumb pull up the rubber cap
firmly in the direction indicated by the
arrow 

b

.

Open the D block
(Refer 2-2.)

6P (DY)

10P (DY)

Four screws

(+ BVTT 4 x 8)

A board

Open the G block
(Refer 2-3.)

Neck assy

Deflection yoke

Picture tube

Three connectors

Anode cap

1

2

3

4

5

6

8

9

7

– 18 –

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.

1) Confirm that the voltage of the pin 2 of CN901 on D

board is within the voltage range shown below.

Standard: 9.00 ± 0.065 VDC

1) Confirm that the HV protector circuit works and TV

Raster disappears when apply the voltage as shown

below between pin 3 of CN901 on D board and

GND using an external DC power supply.

Check Condition: Less than 34.10 VDC

1) Measure HV voltage and record that value.

2) Shorted between pin 1 and pin 4 of CN901 on D

board.

3) Connect to the Constant Current Jig (A) between pin

1 of CN901 on D board and GND, confirm that the
Beam Current Protector Circuit works and HV go

down more than 1.25 kV from the value of (1).

Check Condition: 1.50 mA

1) Connect to the Constant Current Jig (B) between pin

1 of CN901 on D board and GND, confirm that the
Beam Current Protector Circuit works and TV Raster

disappears.

Check Condition: 1.59 mA

1) Confirm that the voltage of pin 3 of CN901 on D

board is within the voltage range shown below.

Standard: more than 28.0 VDC

HV Regulator
Circuit Check

HV Protector
Circuit Check

Beam Current
Protector Circuit
Check

Part Replaced (

]

)

D Board IC901, T902

• Mounted D board

D Board Q660, Q661, D916,

D935, C924, R665,
R667, R940, R980,
T902
• Mounted D board

G Board PH680, Q680, Q683,

D680, R680, R685,
R686, R687, R688,
R689
• Mounted G board

D Board IC901, D904, D907,

D908, R011, R908,
R909, R921, R925,
R926, R929, R930,
T902
• Mounted D board

Input voltage : 100 ~ 240 VAC

Input signal : White Cross Hatch at 107 kHz

Beam control : BRT and CONT 

→

 Minimum

B+ voltage

: 195 ~ 205 VDC

– 19 –

•

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” shall be set at 0.

•

1.

Put the set inside the Helmholtz coil. (“LCC SW” = “12”)

2.

Input the single green signal and set the CONT control to
MAX.

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

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
“MON CON REG2”=152. 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 being
operated, it sometimes gets magnetized, and the system may
not work properly as a result.

(2) Adjust in a non-magnetic field. BV=45uT.
(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”.

•

Write terrestrial magnetism sensor reading VX and VY to
“LCC VX” and LCC VY” respectively. Adjust the landing
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 ± 15

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

128 ± 40

Save the service data.

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

* Adjustment and measurement should be made at the points one

inch inside the fluorescent screen.

 ± 6

 ± 6

 ± 6

 ± 6

 ± 4

 ± 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.

0 ± 3

0 ± 7.5 0 ± 3

0 ± 5

0 ± 5

0 ± 5

0 ± 3

0 ± 7.5 0 ± 3

(µm)

(µm)

10

10

10

10

7

10

10

10

10

(µm)

7.

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 DY TLV VR so that the horizontal trapezoid is
equal at the left and right. Insert the wedge firmly so that the
DY does not shake.

8.

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 ± 40

After adjustment, save the service data.

9.

Remove the sensor and wobbling coil.

10. Switch the signal to R.G.B., and check that each color is pure.
11. Check that the DY is not tilting.

– 20 –

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

XBV

XCV

R

B

B

R

R

B

B

R

B

B

R 

H. AMP

H. TILT (TLH)

YBH

YCH

R B

R B

R

•

(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. (Fig. 1)

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

by using 4-fold poles magnet.

(4) Make a rough adjustment of the V direction convergence by

using “V. STAT”.

* Set so that the protruding parts of

the 2 magnet rings agree with each
other.

*

•

•

(1) 9300K

x = 0.281 ± 0.005
y = 0.311 ± 0.005

(All White)

(2) 6500K

x = 0.313 ± 0.005
y = 0.329 ± 0.005

(All White)

•

•

FBT

IBM AT Computer

as a Jig

1-690-391-21

1

A-1500-819-A
Interface Unit

2

*The parts above (                ) are necessary for DAS adjustment.

1

3

D-sub
(9 Pin [female])

mini Din
(8Pin)

4 Pin

3-702-691-01
Connector Attachment

3

To BUS CONNECTOR

4 Pin

4 Pin

Protrusions

60

°

*

Fig. 1

Fig. 3

Fig. 2

TLV
YCH
YBH

XBV
XCV
APH

B

a

a     3.2 mm
b     3.2 mm

a

b

b

A

MODE

A

B

1, 2

388 mm

291 mm

B

A

MODE

A

B

1

0.24 mm

0.24 mm

2

0.24 mm

0.32 mm