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– 17 –

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

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

+0.0
–0.1

Part Replaced (])

GB board

IC4202
• Mounted GB board

G board

D4220
• Mounted G board
• Mounted GB board

G board

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

GB board

IC4202
• Mounted GB board

G board

R4222, R4223
• Mounted G board
• Mounted 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 Å® Minimum

B+ voltage

: 193~201 V DC

– 18 –

9.

Adjust the DY position and purity, and the DY tilt, and land-
ing of the center and 4 corners with the landing checker.

Note:
(1) Adjust in s non-magnetic field. BV=35uT.
(2) If adjusting in a magnetic fields, add the shift from the non-

magnetic field in your estimation.

<Specification>

Adjust the green of corners 1 to 4, and center 6 to ±5 µm, and red
and blue to within ±7 µm of green, and the difference between
red and blue to within ±10 µm.
Adjust the green of 5 and 7 to within ±10 µm, and red and blue to
within ±7 µm of green, and the difference between red and blue
to within ±10 µm.

(Set each corner to 1st frame of the crosshatch.)

10. 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.

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

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

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.

(4) If the specification cannot be satisfied though the adjustment

of 11 was made, the following adjustment may be made.
a) Adjust the “LCC xx” register that corresponds to the part

to be adjusted. (See the following figure)

Note : “LCC NS” =108~148

except for “LCC NS”=114~142

b) Execute the service saving.

“LCC LT”

“LCC NS”

“LCC RT”

“LCC LB”

“LCC NS”

“LCC RB”

(5) If performing a manual degaussing after adjustment of “LCC

xx”, set “LCC xx” to 128 (of “LCC SW” to 0).
(After degaussing, return the adjustment value to original
value.)

12. Remove the sensor and wobbling coil.
13. Switch the signal to R.G.B., and check that each color is

pure.

14. Check that the DY is not tilting, and fix the purity Mg with a

white pen.

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.

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: Set to É 1k=300 µA with the signal green signal, and af-

ter aging for about 30 minutes, adjust so that it is exactly
this value.

3.

Before making any adjustment, confirm that respective
preadjustment values of the registers listed below have
been entered correctly.

LCC K TEMP

100 LCC R TOL

128

LCC K EW C

105 LCC SW7

7

LCC K NS C

0 LCC TEMP

151

LCC K NS

160 LCC VX

#

LCC K NS FOR ROT 64 LCC VY

#

LCC K ROT FOR NS 46 LCC K VY NS

0

LCC K POL

255 LCC P TOL

128

LCC WO

128

#=Input values in time adjustments

Also, confirm that “LCC NS=LCC LT=LCC LB=LCC
RB=LCC RT=128”

4.

Send the “LCC READ” command of the ECS.
If the ECS command cannot be used, execute the status read-
ing and VX, VY and V TEMP values may be entered to
“LCC VX”, “LCC VY” and “LCC TEMP” respectively.

5.

Execute the service saving.

6.

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 REG 2”=152. Return to the original value after
use.)
Demagnetize the CRT surface with the hand degausser
again.

Note: Hand degauss must be used on stand-by or power-off con-

dition.
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.

7.

Attach the wobbling coil to the designated part of the CRT
neck.

8.

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

1

2

4

3

6

7

5

– 19 –

MODE

A

B

1,3

395 mm

296 mm

2

370 mm

296 mm

a

B

A

b

4,5,8,9

474 mm

266 mm

6,7

474 mm

296 mm

MODE

a 

b 

4

3.0 mm

3.8 mm

other mode

4.4 mm

4.4 mm

Run the service software and then follow the instruction.

(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”.

Protrusions

60°

ƒ

Fig. 1

Fig. 3

ƒ

Set so that the protruding 

     parts of the 2 magnet rings 
     agree with each other.

TLV

YCH

YBH

RV801

A board

APH

XBV

XCV

TLH

XBV

XCV

B

R

R

R

B

B

R

B

B

R 

H. AMP

H. TILT (TLH)

YCH

R 

B

B

R

YBH

R B

(1) 9300K

x = 0.283 ± 0.008
y = 0.298 ± 0.008

(2) 6500K

x = 0.313 ± 0.008
y = 0.329 ± 0.008

(3) 5000K

x = 0.346 ± 0.008
y = 0.359 ± 0.008

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

FOCUS2

FOCUS1

FBT

IBM AT Computer

as a Jig

1-690-391-21

1

D-sub

(9 Pin [female])

mini Din

(8Pin)

To BUS CONNECTOR

Purity

6-pole Mg

B

A

A

0.24 mm

B

7

2,3,4,5,6

0.32 mm

0.28 mm

0.36 mm

MODE

1,8,9

0.28 mm

0.40 mm

Fig. 2

– 29 –

D

A

M

G

L

H1

J

H2

GB

GA

• All capacitors are in µF unless otherwise noted. (pF:  µµF)

Capacitors without voltage indication are all 50 V.

• Indication of resistance, which does not have one for rating

electrical power, is as follows.

Pitch: 5 mm

Rating electrical power 1/4 W (CHIP : 1/10 W)

• All resistors are in ohms.

•

: nonflammable resistor.

•

: fusible resistor.

•

: internal component.

•

: panel designation, and adjustment for repair.

• All variable and adjustable resistors have characteristic curve B,

unless otherwise noted.

•

: earth-ground.

•

: earth-chassis.

• All voltages are in V.

• Readings are taken with a 10 M  digital multimeter.

• Readings are taken with a color-bar signal input.

• Voltage variations may be noted due to normal production

tolerances.

•

*

: Can not be measured.

• Circled numbers are waveform references.

•

: B + bus.

•

: B – bus.

• When replacing components identified by 

, make the

necessary adjustments indicated. (See page 17)

• When replacing the part in below table, be sure to perfome the

related adjustment.

RESISTOR

: RN

METAL FILM

: RC

SOLID

: FPRD

NONFLAMMABLE CARBON

: FUSE

NONFLAMMABLE FUSIBLE

: RW

NONFLAMMABLE WIREWOUND

: RS

NONFLAMMABLE METAL OXIDE

: RB

NONFLAMMABLE CEMENT

COIL

: LF-8L

MICRO INDUCTOR

CAPACITOR

: TA

TANTALUM

: PS

STYROL

: PP

POLYPROPYLENE

: PT

MYLAR

: MPS

METALIZED POLYESTER

: MPP

METALIZED POLYPROPYLENE

: ALB

BIPOLAR

: ALT

HIGH TEMPERATURE

: ALR

HIGH RIPPLE

GB board

IC4202
• Mounted GB board

G board

D4220
• Mounted G board
• Mounted GB board

G board

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

GB board

IC4202
• Mounted GB board

G board

R4222,R4223
• Mounted G board
• Mounted GB board

G board

T4202(FBT)
• Mounted G board

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

G

D

S

2

3

4

5

6

7

8

9

0

!¡

!™

!¢

–

1

G

D

S

G

S

S

D

G

D

Ver.1.4

Transistor
(FET)

Transistor

Transistor

Discrete semiconductot

(Chip semiconductors that are not actually used are included.)

Diode

Diode

Diode

Diode

Diode

Diode

Diode

Diode

Diode

Source

Source

Anode

Anode

(NC)

(NC)

Cathode

Anode

Cathode

Common

Cathode

Cathode

Common

Cathode

Cathode

Common

Common

Common

Common

Cathode

Anode

Base

Emitter

Collector

Base

Emitter

Collector

Drain

Gate

Gate

Drain

Device

Printed symbol

Terminal name

Circuit

*

Anode

Anode

Anode

Cathode

Anode

Anode

Cathode

!£

Transistor
(FET)

Transistor
(FET)

!∞

Emitter

Collector

Base

Transistor

Source

Gate

Drain