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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

.

CN2 (DY)

GND (DY)

CN4 (DY)

Two screws

(+ BVTT 4 x 8)

A board

Neck assy

Deflection yoke

Picture tube

Three connectors

1

2

3

4

6

7

Anode cap

5

– 18 –

Part Replaced (

[

)

RV901

HV ADJ

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) Hardware logic circuit

•

Turn the POWER SW on, and check that the RASTER

fades in.

•

Connect a variable resistor (20 k

Ω

 or more) and an

ammeter in series between FBT pin !] and – 15 V line

(– side of C637). Decrease gradually the resistance of

the variable resistor from maximum to minimum, and

confirm that the Beam Current Protector Circuite

works (TV Rester disappears). The current must be

within the range shown below.

Standard current: Less than 1.09 mA

(2) Software logic circuit

•

Turn the POWER SW on, and check that the RASTER

fades in.

•

Short between + of C639 and GND.

•

Connect a variable resistor (20 k

Ω

 or more) and an

ammeter in series between FBT pin !] and – 15 V line

(– side of C637). Decrease gradually the resistance of

the variable resistor form maximum to minimum, and

confirm that the Beam Current Protector Circuite

works (TV Raster disappears). The current must be

within the range shown below.

Standard current: Less than 1.14 mA

HV Regulator
Circuit

HV HOLD
DOWN Circuit

Beam Current
Protector Circuit

Part Replaced (

]

)

D board IC901, R903, R922,

T901,

RV901

• Mounted D board

D board D913, D916, C923,

R920, R927, R935,
R936, T901
• Mounted D board

D board IC901, D901, D902,

D918, R053, R918,
R923, R928, R932,
R933, R934, R939,
T901
• Mounted D board

* 

Confirm one minute later turning on the power.

•

(1) Confirm that the voltage between cathode of D913

and GND is more than 17.5 V DC.

(2) Using external DC Power Supply, apply the voltage

shown below between cathode of D913 and GND,

and confirm that the HV HOLD DOWN circuite

works. (TV Rester disappears)

Standard voltage: Less than 23.40 V DC

– 19 –

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.

<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 ± 4 0 ± 7.5

0 ± 4

0 ± 4 0 ± 5

0 ± 4

0 ± 4 0 ± 7.5

0 ± 4

(µm)

8

8

8

8

7

8

8

8

8

(µm)

8.

Tighten DY screw.
Torque: 22±2 kgcm (2.2±0.2 Nm)
Auto-degauss it.

9.

Adjustment each top and bottom pins by switching DY neck
up-down, and adjust V. TILT and horizontal trapezoid by
swinging DY neck right-left. And then fix with 4 wedges.
(Insert wedge certainly so that the DY will not loosen.)

Fixing DY with wedges.

“a” and “b” must be equal, and
“c” and “d” must be almost equal.

<How to drive in wedges>

Apply a locking agent to the up-
per wedges only.
In such a case, apply agent so that
it enters both sides of wedge and
also inside the DY.

c

a

b

d

10. Check landing at each corner and in case not in specification,

adjust by sticking disk magnets on CRT funnel. (After plac-
ing disk magnets, absolutely hand degauss and check the re-
sults.)

11. Remove the sensor and wobbling coil.
12. Check that the DY is not tilting. Then, fix purity magnets

with white paint and fix wedge with RTV.

(µm)

± 5

± 5

± 5

± 5

± 5

± 5

± 5

± 5

± 5

•

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 128.

•

1.

Put the set inside the Helmholtz coil.
Set “LCC SW” at 0.
And check “LCC LT”, “LCC LB”, “LCC RT”, “LCC RB” at
128.

2.

Input the single green signal and set the “CONTRAST” to
MAX.
<Landing adjustment luminance>
Landing adjustment after 2 hours of aging by Landing ad-
justment luminance.
*Landing adjustment luminance

:same luminance on aging (Reference: 

Σ

IK=250uA)

*Max luminance

: 110 ch/m 

Σ

IK=750uA

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.
(When degaussing, set the current of LCC at 0.)

Note:
(1) Adjust in a non-magnetic field. BV=45uT.
(2) 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.

Pull the TLH plate nooked on stopper.

6.

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

7.

Adjust the DY position and purity, and the DY tilt, and land-
ing of the center and 4 corners with the landing checker.
Purity Adjustment use 2-pole magnet on DY side, Don't use
on Neck Assy one.

– 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.

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

•

(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 conver-

gence by using 4-fold poles magnet.

•

•

•

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

•

(1) COLOR  INDEX = 3

x = 0.283 ± 0.005
y = 0.298 ± 0.005

(All White)

(2) COLOR  INDEX = 2

x = 0.313 ± 0.005
y = 0.329 ± 0.005

(All White)

(3) COLOR  INDEX = 1

x = 0.346 ± 0.005
y = 0.359 ± 0.005

(All White)

* Set so that the protruding parts

of the 2 magnet rings agree
with each other.

XBV

XCV

R

B

B

R

R

B

B

R

B

B

R 

H. AMP

H. TILT (TLH)

R

B

B

R

V. TILT (TLV)

YBH

YCH

R B

R B

R

Protrusions

60

°

Fig. 1

Fig. 3

XCV

YBH

XBV

APH

TLH

TLV

YCH

Purity

B

a

a     3.2 mm
b     3.2 mm

a

b

b

A

MODE

A

B

1-3

352 mm

264 mm

B

A

MODE

A

B

3

0.24 mm

0.24 mm

1, 2

0.24 mm

0.32 mm

FOCUS 1

FOCUS 2