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– 17 –

D block

G block

D board (Refer to 2-2.)

Rear shield

D,G boards

A board (Refer to 2-4.)

G board

(Refer to 2-3.)

CAUTION : SHORT 

ƒ

 If the claw is hooked,

@

 opening and closing

@

 the board is impossible.

@

 Do not try to do it by force.

ƒ

 If the claw is hooked,

@

 opening and closing

@

 the board is impossible.

@

 Do not try to do it by force.

*

The D and G blocks are not widely
opened after the wires are properly
arranged, as shown in the figure.

– 18 –

Four screws

(Tapping screw)

CN3001

CN3002

H1 board

Two screws

(+ BVWHTP screw 3 x 12)

Bezel

5

6

7

8

2

Two screws

(+ BVTP 4 x 16)

1

H2 board

4

Two screws

(+ BVWHTP screw 3 x 12)

Claw

9

J board

CN4001

3

D block

G block

– 19 –

Anode cap

Purse lock

Deflection yoke

Top cover

TOP VIEW

Open the D blook
(Refer 2-2.)

CN6010

2P (NA)

Four 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

8

Anode cap

2P (DY)

9

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.

– 20 –

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 IC4202

on GB board is within the voltage range shown be-

low.

Standard: 9.00

±

0.10 V DC

1) Using an external DC power supply, apply the

voltage shown below between cathode of D4220 on

G board and ground, and confirm that the HV Hold-

Down circuit works. (TV Raster disappears)

Check Condition: Less than 33.8

  V DC

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 T4202 (FBT) on G board and ground, and

confirm that the Beam Current Protector Circuit

works. (TV Raster disappears)

Check Condition: Less than 1.55 mA

Input the initial regulation value of ABL-SHUTDOWN

that was recorded c)-1).

1) Shorted between pin !] of IC4202 on GB board and

ground.

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

!] of T4202 (FBT) on G board and ground, and

confirm that the Beam Current Protector Circuit

works. (TV Raster disappears)

Check Condition: Less than 1.72 mA

1) Confirm that the voltage of the cathode of D4220 on

G board is within the voltage range shown below.

Satndard: More than 28.0 V DC

HV Regulator
Circuit Check

HV Hold-Down
Circuit Check

Beam Current
Protector#1
Circuit Check

Beam Current
Protector#2
Circuit Check

Voltage of 3rd
winding of FBT

+0.0
–0.1

Part Replaced (])

GB board

IC4202
• Mounted GB board

GB board

G board

D4220
• Mounted G board

GB board

G board

D4204,D4206,D4220,
R4211,R4212,R4216,
R4219
• Mounted G board

GB board

IC4202
• Mounted GB board

GB board

G board

R4222, R4223
• Mounted Gboard

GB board

G board

T4202(FBT)
• Mounted G board

Input voltage : 100–120 V AC

Input signal : White dots or Cross Hatch

Controls

: BRT and CONT 

→

 Minimum

B+ voltage

: 193–201 V DC