Tatung CM-1496 Series, CM-1498 Series Service Information

SERVICE INFORMATION

MODEL: COLOR

CM-1496X

DISPLAY

CM-1498X

MONITOR

~

-

;

~

'i

~

-

COLOR

ro~~~

1.REMOVAL

2.MECHANICAL

3.TECHNICAL

4.

5.

DISPLAY

CM-1496X/CM-1498X

OF

REAR DISASSEMBLY

INFORMATION GENERAL DESCRIPTION 5-1

SWITCHING

5-2

AUTOMATIC

5-3

VERTICAL

OF

COVER

OPERATION

MODE

POWER

DEGAUSSING

DEFLECTION

SUPPLY

CIRCUIT

SERVICE

CIRCUIT

MANUAL

-

PAGE

1 2 3

4

5 5 6 6

5-4

HORIZONTAL

5-5

DYNAMIC

5-6

VIDEO

5-7

MODE

5-8

SELF-TEST

5-9

SIGNAL

6.ALIGNKENT

7.TROUBLE

8.REPLACEMENT ASSEMBLY ASSEMBLY ASSEMBLY ASSEMBLY ASSEMBLY ASSEMBLY

9.CIRCUIT

PINCUSHION

CIRCUIT

CONTROL

CABLE

PROCEDURE

SHOOTING

PARTS PCB-MAIN PCB-CRT PCB-POWER PCB-LINE PCB-LED CRT

BOARD

LAYOUTS

DEFLECTION

CIRCUIT

CORRECTION

CIRCUIT

CONNECTIONS

LIST

FILTER

CIRCUIT

6 7 7 8 9

9 10 14 25

25

29 30 32 32 33

34

10.CIRCUIT

DIAGRAM

36

:

,-

I

,1

Ii

'I

II

/

Ii

~

9

I

I!

•

*

3.TECHNICAL

***f,,*f,(t.:**~,~(;~****~~****~'c~'cf,,**~,

INFORMATION

*

APPLICATIONS:

POWER

VIDEO

SYNC.

SIGNAL DISPLAY

DATA

LINEARITY:

INPUT:

SIGNALS:

CONNECTOR:

TUBE:

AREA:

Analog alphanumeric

Mains

100 -125/200 -240VAC

50/60

1.0A(100 -125VAC)/0.6A(200-240VAC)

Red,

input levels:

Vertical frequency

Horizontal frequency: 31.5 Miniature 14"(l3V),

(CM-1496X) P22 reflectivity

180 x 240 6%

R.G.B.

voltage: Hz

green, blue, analog video signals

D90

phosphor.

mm

Max.

input color display for graphics

use

SWITCHABLE

0 - 0.7Vp-p

shell degree

,0.28mm

light

45% -65%

53 -90

male

15

deflection,

dot pitch.

transmission rate

Hz

KHz/35.5 Pin connector

0.31

(CM-1498X)

KHz

mm

dot pitch,

46%

and

IHSCONVERGENCE:

WHITE COODINATES

USER

OPERATING

WEIGHT:

COLOR:

CONTROLS:

AMBIENT:

Center: 0.3 Corner: 0.5

X:

0.313

Y:

0.329

Power detent), contrast control H.SIZE

Temperature: 0 -

Relative humidity:

12.5

ON -OFF

kg

mm mm

4,5

V.CENTER,

(net)

Max. Max.

(CM-1496X)

switch, Brightness control (with center

V.SIZE

35

C

10 -80%

0.4

H.PHASE

4,5

CONTROL

mm

1,2,3

Max.

(CM-1498X)

H.PHASE

4

.-

*************

*

4.GEMERAL

*

~=~---*

CM-1496X/CM-1498X dot pitch signals

text

display.

It

is various industry graphic standards such as, the 800X600, sizing

to

l024X768.

A

self-test

from

cted white with a

CRT

and

TTL-level seperte sync.

designed to provied

IBM

circuitry

pattern

the driver source. raster vertical

is a high

with etched

8514A

extending

black bar

l024X768

that

provides automatic

shall

resolution

faceplate.

you

be

available The

beyond

on

the

color display using a 0.31/0.28

Analog

signals

with a

and

self-test

the display bezel at the top

left

wide

incorporates the automatic

when

and/or

are adopted for graphic

range

sizing

the signal cable

pattern

right

16-1evels

of

compatibility with

IBM

VGA

PS/2, super

resolution

will

consist

edges.

R.G.B.

of

640X350

is and

ma

video

and

VGA

vertical

up

disconneof a full

bottom,

4

5-1

SWITCHING

The

s~itching

~ormal

case and

a secandary voltage

A.

The

follows:

1.

aui

The

effects the switching

~

Enabling

Simultaneously with

becomes exceptIon resistant

3.

Enabl

In current supply for the control additional

ready for operation.

,;<

5.

MODE

- .

TDA4601

POWER

is

transistor

and

overload operation as well as during disturded operation . In

of

disturbance the drive

SUPPLY

designed for driving

in flyback converter

rise

start-ur

ld-ur

procedures include three consecutive operating

internal

ref erence vol tage

DESCRIPTION

CIRCUIT

of

IS

prevented.

OF

OPERATION

controlling

power

the switching

intenal reference voltage supplies the voltage

charging

of

the coupling

electrolytic

transistor.

of

internal

available providing

of

the control

voltage reference voltage va

reaching approx

all

lOgIC

with a thermally

12V.

component

current supply.

ing

of

control lagH

conjunction with the generation

stabilization

circuit

of

lOgIC

The

the reference voltage.

is

activated

Integrated

,;:

and

protecting the

supplIes during

transistor

is

start-up

inhibited

phase

regulator

capacitor cannected to

Vl=4V

an

Internal

voltage

elements. with the

stable

and

by

means

circuit

overload

of

is

as

and

The

an

then

B.

Normal At feedback ( control input overload

~ectified

amplifier operates with

a~prox

The

current simulator Pin 4 the operating range The at collector

propovtion range

b~tween

voltage

operation mode/control operation

the input

of

coil

2 the zero passage

~re

registered

and

1.4mA

overload

collctor Pin

4

amplitude

depending

identification

current is sImulated

and

internally

fluctcations

an

input voltage

on

the

set threshold voltage current applIcable with the switching to

~he

of

the control a

DC

WhICh

increased

voltage

can

vary

arnplifie~

~apactance

clamped

up

to a

mode

of

the frequency provided

and

forwarded to the control logic Pin 3

standing

internal

limits

by

identification)

of

the feedback

of

approx voltage reference. in conjunction with

of

the control amplifier

an

external

RC The transistor

caos

thus the reguired operatIng

is

established

at

2V

and

max

amplitude

the range

a

sa~tooth-snaped

of

4V during secondary load reductlon the switching frequency and.

Ie,

are present at

A~d

to R804 resistor

the

Pin 5

~t

is possible

the outp;.it:1.t ?in 8

5.

the

bas~

current amplifler forwards the sawtooth-shaped

the output

1S

of

present

6.

between

determines the

switching

transistor.

to

4i11

externally

be

Inhibited

inhibit when

A current feedback with Pin 8 and

max

amplItude

of

7,

the

volltage

an

the applIed value

base

by

the

receives the

coil

2V

the control

and

a current

collector

combinatIon present

largest

possible

increase in

of

control

lies

rising

(reference voltage)

is

increased

the operatlon

of~Vref

external

of

V4

voltage

resistor

of

the

-O.IV

the

driv1ng current for

of

AC

C.

Protective The

base

outpu~

~r~~:sistor

supply

of

voltage

operation

mode

current shut-down

l.

61,1

P

i;l

7 to

1S

inhibited T his

a:

Pin 9 reach'Os

.

activated

As

a

result protective

a

va

lue~6.

5

by

the

control logic

drive

the

measure

7

V

or

if

clamps

of

the switching

is

enabled

vol

tage at

if

.::;;:

the the

Vre~

2

...

....

-.:

-

-O.IV

5-2

AUTOMATIC

a~e

present

DEGAUSSING

at

CIRCUIT

5.

Posistor

(ADG)

R803

circuit

and

degaussing

to demagnetic the

CRT.

Posistor

line seconds, degaussing current thus decrease to function

5-3

VERTICA~

The

R343.

running frequency The

mirror Pin 9

C305 Pin Pin

shows

low

voltage. current

resistance is

completed.

DEFLECTION

vertical

C310

resistance

and

of

and

10

of

12

of

sync. signal is applied to Pin 5 & Pin 4

connected to

of

between

then the height

Q301

is

output

C306.

This

Q301

is the output

Q301

is the inverting input

resitance value in normal temperature.

of

about

of

posistor increase

CIRCUIT

the

oscillator

Pin 7

of

the

is

also the input

coil

L991

compose

shadow

20

Ap-p

mask

flows into degaussing

rapidly

less

3,

Pin 4 inside

of

0301

and

the scanning.

current

of

the buffer stage.

mirror

of

the amplifier.

an

Automatic Degaussing

and

internal

due

than

120 m Ap-p,

and

Pin 6 determin the

to

shield

when

rising

of

Q301.

in the

apply

coil.

after

in heat,

degaussing

R342. free-

Q301.

ground defines the current

that

of

buffer stage.

changes the

series

AC

of

R307 centering and

the parabola. available across across output

The deflection used

The

and

R310

define the

of

the output voltage.

R310.

applied at the feedback input Pin

R312. R305, scanning current.

output

of

po~er

yoke

to

stabilize

supply voltage

DC

level across

R308

C309.

R30B

and

R310

produce the

amplifier

by

a negative slop current ramply.

the

po~er

of

the

from

amplifier.

power

output stage

the trace tlme the supply votage IS obtained

by

D301.

internal

15

from

~ump

to Pin

14

5-4

HORIZONTAL

The

positive horizontal sync. pulse amplified ty /

R403

while

dUrlng

flyback generator.

is

the output

lo~

to

high

condition.

2.

of

Q301

is the

DEFLECTION

to

Pin 3 of

Q406.

Then the

the

retrace

of

the flyback generator

An

external

main

supply voltage input.

CIRCUIT

be

applied through the

horizontal

Ie

C309,

and

the

the Pin 1

time

this

capacitor

from

Pin 6

Q402.

so

allowing a correct

C308

in conjuction with

12

of

0301,

AC

feedback voltage, taken

linearity

of

Q301

is

forced at Pin

from

the

a small part

correction

drives the

R309

and

main

supply votage

Pin is supplied

that,

differential

of

when

C304

Q201

driven.

transfers

is

converted

circuit

on

vertical

C307

2.

During

from

R307

of

the

are

the

jumps

the

and

C407

The

positive

~ntegrated

horizontal flyback pulse derived

by

the comparable

from

Pin 5

sa~tooth-waveform

6

generator

of

FBT

which

T403

is

com-

posed of

Pin 4 The

ween

the supper

R410,

of

0402.

discriminator

the sync. input

imposed

low-pass-filter

R406

via The

to Pin 7

oscillator the timing. horizontal

The

predriver output

led

by

oscillating

R402

and

R411. R423.

inside the pulse outRut

R407,

of

Q402.

inside

R404,

R405.

of

R403

at

C408.

from

Pin 3

C404

and thereby

IC

Q402

R422,

frequency.

Q402

is

Pin 8 of

IC

from

C403,

is

at

Q402 and

an C402

0402.

and

C410.

detects

the sawtooth-waveforme Pin 5 AFC

controlling

RC

and

Pin 1

then

be

applied via

the phase

difference

from

of

0402

is

integrated

voltage

is

the

oscillator.

obtained

type with Pin 7 used to control

C410

of

altogether

which

duty cycle

determine the

and

is

control-

C405

to

betPin 4 . by

the

applied

Regulated voltage applied

The

output signal

coupled

by

T401

to

the horizontal output stage

from

at

Pin 6

Pin 1

of

0402

Q402

is

then amplified

thus sawtooth-waveform current through the horizontal

obtained. Also during the

retrace flyback pulse at about this voltage

5-5

DPC

The

raster

The

R326, R327,

pulse

of

about

CIRCUIT

Side

Dynamic

width

vertical

is

transfered

22.0KV

Pincushion Correction

as

a function

castle-waveform

R328,

for side pincushion correction,

Q302

and

Q303

stages

able The

reactor inductance

T402.

of parabolic current. horizontal

deflection

the

time

of

the

1100

volts

and

rectified

tor

anode

ot

vertical from

C316

etc.

to

and

then

T402

this

output winding is

drives

output winding

yoke.

horizontal

is

produced

by

the

of

CRT.

circuit

deflection.

Pin 1

of

produce a parabolic

this

parabolic voltage

the control winding

is

about 8 - 9

Q403

deflection. at

the

FBT

T403

(Side

0301

is

modulated

inserted

volts.

by

for

ON-OFF

deflection

a horizontal

collector

to obtain high

DPC)

modulates the

integrated

waveform

is

amplified of

the

by

the

in

series

Q401

and

control,

coil

is

of

Q403.

by

C314,

necessary

by

satur-

vertical

with the

The

to

5-6

VIDEO

The color.

:dentical. Video

and The Analog

to input

Contrast is Pin 7

horizontal

correct

yoke

current

side pincushion

is

th8n modulated

distortion.

CIRCUIT

color display contains three video

amplifiers,

these three amplifiers for the red, green

amplifier

consists

of

preamplifier cut off adjustment CIrcuit. operation

video signals IS preadjusted

of

FBT

of

only Q501. DC

controlled

(T403)

to

one

channel (blue) is described here.

by

R502

from

14

of 0501.

PIS

of

0501.

The

7

Q501

and coupling

output

by

the

correction

one

and

blue

(H51387P),

clamp of

pulse provided

Q501

is

voltage

for each primary

CRT

guns

are

output stage

VIA

C501.

C502

from

at

21.

C504 The

is

B+

used for

of

preamp.

clamp

(12V)

pulse to charge.

and

output stage

is

provided

from

S.M.P.S.

5-7

"The

co~posite

clamp MODE

(1)

the Blanking level

CONTROL

HORIZONTAL H.Sync.

(F/V

1.

So

and

"LOW"

control

(2)

HOR.

WIDTH

When

Hf=31KHz,

is

"V',

90VDC 105VDC change as

Hor.

(3)

HOR.

OSC.

When

Hf=31KHz,

then

#12#14#

the time constant

blanking pulse

CIRCUIT

FREQUENCY

pulse with

CONVERTER)

we

get a when

Hor.

Then

"HIGH"

Hor.

width,

CONTROL

Q212#1

QE801#B

was

is

sent to

the

base

width

FREQ.

sent

current

when

CONTROL

is to

Q212#1

are connected.

of

is

to A suitable

DETECT

different there

freq.

Hor.

"L", FBT

FBT#9

at

osc.

is

#9.

and

of

ar-e

Pin 1

is

"H", QE801

QE801.

Hf=35KHz.

is

"H".

Hor.

osc.

provided

position.

frequency

different

of

Q212

35.5KHz.

freq.,

Q209#C

cutoff,

When

Hf=35KHz.

DE801

is

then

Q209#C

When

Hf=35KHz

circuit

from

vert.

was

voltage

when

This signal

Hor.

phase.

is

"L",

then

cutoff.

change

is

"L".

Q203#13#14

will

circuit

sent to Pin 6

at

the output Pin

Hor.

freg.

can

Q214#C DE801

QE801

is

is conducted

Adjusting

the output

Q203#9#10#11

are connected,

be

changed.

to

Q407.Gl

of

is

31.

be

used

"H".

QE802#C

conducted

RE810

of

QE801

is

Q211_

5KHz

to

and and

can

so

"L",

(4)

HOR. When connected.

(5)

VOLTAGE Q201 posltlve. get a "H". reference). sync.

MODE

1 +

MODE

2

MODE

3

(6)

SIZE Q208 Q209#C picture size "H". disabled.

PHASE

CONTROL

Hf=31KHz,

AT

POSITIVE

74LS86

#3

"L"

at

pointHD.

It's

the

The

H.SYNC.

CONTROL

OF

74LS138

is

"L".

of

so

that

Since

Q203#15#2

is

an

also positive. This pulse

same

output

V.SYNC.

+ H

MODE

is

a 3-to-8 decoder (Multiplexer). 0205

mode

Q208#13#14

Q214#C

are connected.

END

.OF

C204

XOR

LOGIC

However

condition

at

POINT

3

is

conducted. Adjusting

3.

From

are

is also

When

(POINT

IC.

"D")

If

the input pulse

will

a negative pulse

at

point

#8

and

#6

are

"D"

L H

table 1 we

"H".

"H"

POINT

H

L

H

can

D202/0204

R241/R207

Hf=35KHz.

and

C203

be

filtered

will

HE".

always

Q203#15#1

(POINT

be

(See

HE") of

by

filtered

tabe 1 for

are

#2

C204

as

positive for easy

"E"

know

TABLE

R315

that

1

When

can

Q208#1#2

fH=31KHz.

vary the

are cutoff R208/R211 are

are also disabled too.

is to

a

are

(7)

SIZE From Adjusting adjusting

(8)

SIZE

CONTROL

table

OF

1.

R208 R208

CONTROL

OF

MODE

DIE

can

vary

since

MODE

2 are

picture

R208 1

H/L,

is

Q208#14

size

parallel

8

is

"L".

R315.has to

to

R315

now.

0202

are conducted.

be

preseted before

.-

Q2081l3

(9)

SIZE Q304(PWB-1627) delay the sync. pulse. around voltage.

0305#C

available

fH=35KHz)

(10)

SIZE When There

condition,

have disconnected adjusting.

SELF

5-8

Self via with black

is

connected

a dark screen.

is

CONTROL

11.6mS. is

CONTROL the period

is a negative pulse at

enough

TEST test

signal suppied

R214,

R215,

vertical

"L",

R211

is availabe

OF

KODE

4

74LS123

When

We

The

DC

voltage

,

0210tC

parallel

in series to

OF

MODE

5

of

sync. pulse

will discharge

"L

and

n

C322

voltage

and

R207

from

R216

to

bar

on

to

a system unit the

and

is a

monos

table multivibrator.

In

mode

4,

delay

is

from

"H",

to

that

Pin 5 will

then

R340,

pulse for 11.6aS, 0213#14#13

R241.

is

much

0304#5.

by

the

to

saturate

is disabled.

heater buffered the video input the

left

and/or right edges.

collector

parallel

the period

make

(R241

is

longer than way

0305

Only

by

to

generate

of

to

R315

of

vertical

Q305

saturated.

are connected.

always

11.6mS

Once

of

Then,

the pulse

D312 . So,

R241

is

0205,

Q213#14#13

0206,

full

When

0204

is

grounded

We

use

it

sync. is

it

becomes a DC

When

R207

available

(e.g

when

18mS)

in

C322

cannot

will

available for

0207

white screen

the display

to

make

to

is

"L"

and

5-9

SIGNAL

1 2

3 4 5

6

7 8

CABLE

CONNECTIONS:

Signal

------ ------

Red

Signal 9

Green

Blue

Jumper

Signal

tD

10 Self-test Red

Return Green Blue

Return

10

11

12 13 14 15

Signal No

Digital

Jumper

No

Horizontal Vertical No

Ground

to Pin

Sync.

10

.-

9

':.

6.

Al.l

GMMEMT

6-1

o

5

1

EQUIPl'IENTS

1.

Manual

2.

DSClll.Qscop~

3.

D~gi!al

4. Color a:1alyzer

5.

Pdt:'

6.

EHT

meter with high voltage

5-2

POWER

SUPPLY

degaussing

+

probe

vcltmeter

OUTPUT

coil

VOLTAGE

PROCEDURE

probe

l~

Connect a DVM means

6-3

VERTICAL

of

Connect

to S.K.P.S. output red wire adjust the voltage to

R813.

FREQUENCY a frequency counter across the

the frequency. disconnected

6-4

HORIZONTAL Use a test

and

R405(35.5KHz)

6-5

PINCUSHION

Straighten

6-6

WIDTH

~djust

6-7

VERTICAL

from

FREQUENCY

pattern.

the side

the

data

CENTERING

Center the data area with

To

49Hz

the

Without

to

get the color bar in

lines

area width

PC.

by

means

horizontal sync. input. adjust

with

to

240

R338.

R327

+/-

of

and

vertical

R314.

an

R328.

5

mm

using

deflection

the

signal

upright

L402.

coil.

cable

R422(31.5KHz)

position.

(fH=31.5KHz)

90V

adjust

must

by

be

6-8

VERTICAL

~cjust

6-9

HEIGHT 3 (480

LINEARITY

the squares equal in height with

Adjust data area height

6-10

HEIGHT 2 (400 Switch

with

6-11

HEIGHT 1 (350 Switch to

with

6-12

HEIGHT 5 (600

to

R208.

150

R211.

lines)

to

lines)

400

lines

(Be

sure that height 3

mode. Adjust data area height to

lines) lines

(Be

mode

sure that height 3

lines)

R316.

180

+/-

5

mm

with

R315.

has

been

adjusted)

Adjust data area height to

has

been

aajusted)

10

180

+/-

+!-

5

mm

.-

Switching to

wi

6-13

HEIGHT 4 (768

th

R241.

600

lines

lines)

mode. Adjust data area height

to

180

+/-

5

II

Switching with

R207.

6-14

FOCUS

ADJUST

Adjust

6-15

WHITE

Turn

X/Y the brightness

minimum. Turn

the sub-brito

-25V. Turn

the

disappears.

Turn

the

achieve

0-5

F.L.

Use

full

at

detent, coordinates. to achieve correct

to

768

FBT

lines

(Be

sure that height 5

focus

VR

mode

to

get best

VR

Set cut-off drive

VR

R443

G2

control to a position

brightness

VR

to

the color coordinates

field

white pattern, turn the

adjust

Then

R502, turn contrest X,Y

coordinates.

Adjust data area height to

has

been

adjusted)

overall

to

center

VR

R910/R940/R970

to a position

max.

and

X=0.313

focus screen.

detent

position, to center.

where

to get the brightness

adjust

the

Y=0.329

contrast

R532

and

VR

R562

to get

to achieve the correct 3J.L.

contrast

to get the

R910,R940

roughly

to

maximum,

Adjust

180

+/-

5

mm

VR

to

Gl

voltage

is

just

and

brightness

R970

to

brightnes

X,Y

R910/R940/R970

F/V

6-16

Adjsut

between

INTERLACE

6-17

CONVERTER

R235 Q212#3(+)

ADJUSTMENT: VR

to get

and

ADJUSTMENT:

Receiving 1024x768(interlaced)

Adjust

R218

so

that

(MODE

0.7V

Q212#2(-)

small "s"

3,

FULL

+/-

0.1 between

after

signal,

is

not

WHITE

SIGNAL) #P2

warm

up

the

display small

distorted.

(+) set

and

for

"s"

character.

#P1

20

minutes.

(-)

or

.-

11

I.

IBm

Magnets Ring

Deflection

Yoke

Stopper

6 - Po

CRT

le

Convergence magnet

Neck

~-?ole

o

6-18

5

STATIC

NOTE:

t

(1)

(2)

(3)

CONVERGENCE

Before

be

Apply

attempting

operate for

the crosshatch pattern to the display.

Adjust the pa

ttern.

ADJUSTMENT:

any

at

least

BRIGHTNESS

Refer to the structure the

relative

. I

",U"

..

REO·-

--

_.

position

BLU

.RcD

+f

I

-

--

of

I

convergence adjustment, the display should

thirty

and

of

the convergence

convergence

minutes.

CONTRAST

picture tube

magnet

controls for well defined

(See

Fig

6-1) to

make

sure

magnet.

RED

/SLU

GAN

RcD

;(

_.

__ • __

r=ff="

BLU

GRN-

---

I

..l._

--I

I

I I

I

-l

Fig

(4)

Adjust them

and

of

the picture

(5)

Turn

both

superimpose red screen

(6)

Adjust

green

rotating

(7)

Repeat

6-2

two

tabs

of

superimpose

tabs at the

(See

Fig

two

tabs

one.

Adjusting the angle

both

magnets

(See

6-2)

of

and

6-pole

the 4-pole

red

and

Fig

6-2).

same blue horizontal lines

affects

Magnets

blue

tile

Magnets

the horizontal

adjustments (4). (5). (6).

12

Fig

6-3

to

change

vertical

keeping

to

superimpose red/blue line with

affects until

lines

their

the

best convergence

the angle in

the center area

angles constant to

at

the center

vertical

lines.

lines

(See

between

of

Fig

6-3)

is

obtained.

the

and

.-

Tatung CM-1496 Series, CM-1498 Series Service Information

Specifications and Main Features

Frequently Asked Questions

User Manual