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– 13 –

Anode cap

Purse lock

Deflection yoke

Top cover

TOP VIEW

Open the D blook
(Refer 2-2.)

CN508

2P (DY)

2P (NA)

Two screws

(+- BV tapping screw M4 x 8)

A board

Open the G blook
(Refer 2-3.)

Neck assy

Deflection yoke

Picture tube

Three connectors

1

2

3

4

5

6

7

9

8

Anode cap

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 

.

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

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.

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.

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

.

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

.

Install the anode cap as shown a figure.

– 14 –

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 !. of IC901 on

G board is within the voltage range shown below.

Standard: 9.00

±

0.10 VDC

1) Using an external DC power supply, apply the

voltage shown below between cathode of D916 on G

board and ground, and confirm that the HV Hold-

Down circuit works. (TV Raster disappears)

Check Condition: Less than 31.30 VDC

1) Record the initial regulation value of ABL-

SHUTDOWN and using a PC computer, input the

“255” for maximum value of resistor.

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

!] of T902 (FBT) on G board and ground, and

confirm that the Beam Current Protector Circuit

works. (TV Raster disappears)

Check Condition: Less than 1.34 mA

Input the initial regulation value of ABL-SHUTDOWN

that was recorded c)-1).

1) Shorted between pin !] of IC901 and ground.

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

!] of T902 (FBT) on G board and ground, and

confirm that the Beam Current Protector Circuit

works. (TV Raster disappears)

Check Condition: Less than 1.63 mA

1) Confirm that the voltage of the cathode of D916 on G

board is within the voltage range shown below.

Satndard: Less than 23.30 VDC

HV Regulator
Circuit Check

HV Hold-Down
Circuit Check

Beam Current
Protector Circuit
Check-1

Beam Current
Protector Circuit
Check-2

Voltage of 3rd
winding of FBT

Part Replaced (])

G board

IC901
• Mounted G board

G board

D935
• Mounted G board

G board

IC901, D933, D934,
R907, R908, R909,
R910
• Mounted G board

G board

R973, R974
• Mounted G board

G board

T902 (FBT)
• Mounted G board

Input voltage : 100–120 VAC

Input signal : White dots or Cross Hatch

Controls

: BRT and CONT

→

Minimum

B+ voltage

: 175–185 VDC

– 15 –

•

1.

Enter the full white signal. (or the full black dots signal).

2.

Adjust the contrast to the maximum.

3.

Make the screen monogreen.

4.

Adjust the brightness is easy to see with the G2 resistor.

5.

Reverse the DY, and adjust coarsely the purity magnet so
that a green raster positions in the center of screen.

6.

Moving the DY forward, adjust so that an entire screen be-
comes monogreen.

7.

Adjust the tilt of DY, and fix lightly with a clamp.

•

1.

Put the set inside the Helmholtz coil.

2.

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

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

age of 

Σ

1k 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 1K 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
“MONCONREG2”=152. Return to the original value after
use.)
Demagnetize the CRT surface with the hand degausser
again.

Note:
(1) At the degaussing, set LCC current to zero.
(2) Adjust in s 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.

Note: Using RV701, 702, 703 and 704 on the L board, adjust the

landing of four corners.

7.

For the up/down and left/right swing, swing the DY and in-
sert a wedge so that the up and down pins are equal at the top
and bottom and 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
RV701, 702, 703 and 704 on the L board. If this adjustment
failed, attach the Disk-Mg onto the funnel section and add
correction value.

Note:
(1) Do not paste more than 2 magnets to one corner.
(2) Paste within 80 to 100 mm from the DY on the diagonal line

of the magnet.

(3) If using the magnet, be sure to demagnetize with the hand

degausser and check. (At the degaussing, set LCC current to
zero.)

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, and fix the purity Mg with a

white pen.

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.
Adjust RV 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

(

µ

m)

(

µ

m)

10

10

10

10

7

10

10

10

10

(

µ

m)

– 16 –

B

a

a 

 3.5 mm

b 

 3.5 mm

a

b

b

A

MODE

A

B

9

350 mm

280 mm

1-8, 10

373 mm

280 mm

B

A

A

0.24 mm

B

9

0.28 mm

0.28 mm

0.32 mm

V

MODE

1-8, 10

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.

•

•

(1) 9300K

x = 0.283 

±

 0.010

y = 0.298 

±

 0.008

(All White)

(2) 6500K

x = 0.313 

±

 0.010

y = 0.329 

±

 0.008

(All White)

(3) 5000K

x = 0.346 

±

 0.008

y = 0.359 

±

 0.008

(All White)

•

(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 direction convergence by

using H. STAT VR (left side of the video block).

(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.

XBV

XCV

B

R

B

R

R

R

B

B

R

B

B

R 

H. AMP

H. TILT (TCH)

YBH

YCH

R B

R B

•

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

H.STAT

Magnet

Protrusions

60°

ƒ

Fig. 1

Fig. 3

Fig. 2

TLY YCH YBH

APH

TLH

XCV

XBV