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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

.

2-3

    A board

10

     Anode cap

8

     Screw
     (+P 4 x 12)

6

     Screw
     (+P 4 x 12)

4

     Three connectors
     (CN2, 4, GND)

9

     Screw
     (+BVTT 4 x 8)

1

CN4

CN2

GND

    Stand assy

3

     Hook (17)

5

     Hook (17)

7

     Two screws
     (+BVTP 3 x 10)

11

     Four screws
     (Tapping screw 5 : U/C, SH model)
     (Self tapping  screw 5 : AEP, UK model)

12

     Chassis assy

13

     Picture tube

16

Cushion

    Two claws

2

     Deflection yoke

15

     Neck assy

14

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
• Mounted D board

D board D913, D916, C923,

R920, R927, T901
• Mounted D board

D board IC901, D902, D918,

D919, R923, R928,
R932, R933, R934,
R942, R944, R945,
R947, R948, R951,
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

3-1

•

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.

2.

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

<Landing adjsutment luminance>
Landing adjsutment after 2 hours of aging by Landing adjustmet
luminance.

•

Landing ajdustment luminance
: 1/2 of Landing between COOL and HOT

(Reference:  IK = 200 µA)

•

Max luminance
: 120 cg/m

2

  IK = 650 µA

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.

(1) Adjust in a non-magnetic field. BV=55uT (SH Model).
(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.

With landing checker adjsut DY position, punity, DY tilt,
DY center and landing of hte 4 corners. Purity Adjsutment
use 2-pole Mg on DY side.

8.

Fasten DY with screw.

Note: Torque 22 ±2kg·cm (2.2 ± 0.2 Nm)

Perform auto degaussing.

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.

 ± 7

 ± 7

 ± 7

 ± 7

 ± 5

 ± 7

 ± 7

 ± 7

 ± 7

<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 ± 5

0 ± 7.5 0 ± 5

0 ± 5

0 ± 5

0 ± 5

0 ± 5

0 ± 7.5 0 ± 5

(µm)

(µm)

10

10

10

10

7

10

10

10

10

(µm)

Fixing DY with wedges.

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

9.

Adjust vertical swing with vertical pins, and also adjust hori-
zontal swing so that horizontal keystone and vertical tilt are
optimum, then fix with four wedges.
(When fixing DY with wedges, insert wedges completely so
that the DY does not shake.)

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.

<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.

10. Check the landing of each corner, and if they do not satisfy

the specification, paste a Disk-Mg onto the funnel and ad-
just.

11. If using the magnet, be sure to demagnetize with the hand

degausser and check.

12. Remove the sensor and wobbling coil.
13. Check that the DY is not tilting, and fix the purity Mg with a

white pen.

c

a

b

d

4-1

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.

•

•

(1) 9300K

x = 0.283 ± 0.005
y = 0.298 ± 0.005

(All White)

(2) 6500K

x = 0.313 ± 0.005
y = 0.329 ± 0.005

(All White)

•

•

Adjust the focus volume 1 and 2 for the optimum focus.
Standard: HMC, VMC ± 0.1 mm (In the center of screen)

Protrusions

60

°

Fig. 1

Fig. 3

* 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)

YBH

YCH

R B

R B

R

FOCUS 1

FOCUS 2

XCV

YBH

XBV

APH

TLH

TLV

YCH

Purity

B

a

a     2.4 mm
b     2.4 mm

a

b

b

A

A

B

4 : 3

312 mm

234 mm

5 : 4

293 mm

234 mm

B

A

MODE

A

B

C

f

H

 

  

 60 kHz

0.24 mm

0.24 mm

0.32 mm

f

H

 < 60 kHz

0.24 mm

0.32 mm

0.36 mm

4-2