EMERSON TC1972D, TC1972D TV Service Manual

SERBIKE

MAWAL

‘,:, ”

TCl9i’m

CAUTION

Before

this

Servicing the chassis. read the “IMPORTANT SERVICE SAFETY INFORMATION” on

manual.

SPECIFICATIONS

SPEAKER

VOICE

ANTENNA
RECEIVING

UHF. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CATV . . . . . . . . . . .

.

..Carrier
SoundIFCarrier
Color

WEIGHT
DIMENSIONSS

SIZEE

COILIMPEDANCE . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1/16"

INPUTT

IMPEDANCE . . . . . . . . . . .

CHANNELS

.

.

Sub -

........................................................................

Frequencyy...................

.......................

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency

Frequency

...................................

...................................

....75

.

..................

,,:

6KHz

0.33

.

8ohms

ohm

.

.

.

0+/-3db

oz.

Magnet

at

600Hz

Coaxial

.

23-36 .

input

.14-69

.

.

.

14-22

.

(AA-FFF)

.

45 .75MHz
41

.25MHz

42

.17MHz

38

lbs

19’ REMOTE CONTROL COLOR
TELEVISION WITH ON-SCREEN
PICTURE CONTROLS

AKB

CCD

AUTOMATIC

KlNE

CLOSED CAPTION DECODER

CONTENTS

IMPORTANT

ELECTRICAL ADJUSTMENTS

1.

BEFORE MAKING ELECTRICAL ADJUSTMENTS

1-1.

2.

BASiC

2-1.
2-2:BRIGHT.

2.3:
2-4.

2-5.

2-6.
2-7.

3.

PURITY

3-1.

3.2:
3-3.

3-4:
MAJOR
SEMICONDUCTOR

BLOCK
PRlNTED CIRCUIT

MAIN.
CRT/REMOCONN

SCHEMATIC DIAGRAMS

TUNERR
IF/MICON...
CHROMA
DEFLECTIONN

POWER/AUDIOO
MECHANICAL
MECHANlCAL
ELECTRlCAL

SERVICE SAFETY INFORMATION

PREPARE THE FOLLOWING

TOOLS FOR ELECTRICAL

AOJUSTMENTS

VIF

ANDD

AFT

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

AGC.

CUT

OFF

FOCUS . .

VERTICAL

VERTICAL

HORIZONTAL POSITION

AND CONVERGENCE ADJUSTMENT

STATIC CONVERGENCE ROUGH ADJUSTMENTj

PURITYy
STATIC CONVERGENCE
DYNAMIC

COMPONENTS

DIAGRAM,

......................................................................

..........................................................................

...................................................................

........................................................................

..................................................................

EXPLODED VIEW.

REPLACEMENT

REPLACEMENT PARTS

TINT AND

............................ 5

SIZE

....................

POSITIONN

...............................................................

CONVERGENCE.

LOCATION GUIDEE

BASE

CONNECTIONSS

..............................................................

BOARDS

............................................................

............................................................

MEASUREMENT

ADJUSTMENTS ....

COLOR

............................................

....................

.......................................

.................................

............................

.............................

......................................... 7

PARTS LIST................. 8

LIST

......

page 2 of

BIAS

...................

.3.

4

...-............13. 19

...

10..

3

16

2

, ,
. 2

.
. 3
14
.

3

5

5

j

5

5

5
6
6

7

8

9

2

5

ELECTRICAL ADJUSTMENTS

1. BEFORE MAKING ELECTRICAL
ADJUSTMENTS

Read and perform
the circuits or replacing electrical parts or
assemblies.

CAUTION

Use

an isolation transformer when performing

any service on lhis chassis.
Before removing the anode cap. discharge

electricity because it contains high voltage
When removing a

alter unfastening or changing a wire. be
put the

Inferior
transistors. When replacing
use only specified silicon grease
Remove all old silicon before applying new
silicon.

l-l:

Prepare the following measurement tools

wire

silicon grease can damage

for electrical

1. Sweepmarker Generator

2. Oscilloscope

3. Digital Voltmeter

4. Color Bar Generator

these

PCB

back in its original position.

adjustments

adjustments when repairing

or related component.

IC’s

and

IC’s

and transistors.

(YG6260M).

PCB

sure

to

ohm

1OK

12V

77

AGC TP210

4. Adjust
becomes as shown in Fig. 2-l-b.

5,

6.

L205

until the waveform marker (45.75MHz)

45.75MHz

1

Disconnect output terminal of the sweepmarker

TP201.

generator from
of the tuner pack.
Adjust tuner pack coil until the

becomes as shown in Fig. 2-l-c.

then connect it to TP

waveform

BASIC ADJUSTMENTS

2.
2-1:

VIF AND AFT

NOTE

Connect input and output terminals of the
sweepmarket generator to the circuit as shown

in Fig. 2-l-a. then adjust it.

SWEEPMARKER
GENERATOR OUTPUT

SWEEPMARKER
GENERATOR

INPUT

-60

I

1. Connect output terminal of the sweepmarker
generator to TP201. (Connect a
resistor between them.)

2. Connect input terminal of the sweepmarker

to

generator

3. Connect a
terminal
adjust
oscilloscope readable.

TP204.

1OK

ohm variable resistor to IF AGC

(TP210). 12V

to make the waveform of the

line and ground. then

0.022.uF

47KohmIN60

2.7K

““E

ohm

TP

,GND

Fig. 2-1

41.24MHz

7

Disconnect the

and

2.7K

ohm resistor.

8.

Disconnect input and output terminals of the
sweepmarker generator.
Connect the AFT adjustment oscillator (45.75MHzl

9

to

TP,

of the tuner pack through a

a

resistor.
Connect the digital voltmeter to

10
11

Adjust
of

4.5VDC

L204

TP206

changes dramatically. and adjust to

at that point.

10K

ohm variable resistor

2.7K

ohm

TP206.

to find the point where the voltage

2-2: BRIGHT, AGC, TINT AND COLOR

On-Screen Display Adjustment

Insert

the point of a straightened paper clip into
the hole on, the remote control marked with
arrow as shown in Fig. 2-2.

The adjustment mode display will appear as

in

Fig.

2-3.

an
shown

3

ELECTRICAL ADJUSTMENTS

NOTE

Use

the

1 -

7

keys on the remote control to Select
the options show” in Fig. 2-3.
Press the

7

key to end the adjustments

ADJUSTMENT MODE

1. AGC/BRIGHT/TINT/COLOR

2. SUB BRIGHT AUTO

3. AGC MANUAL

4. COLOR MANUAL

5. TINT MANUAL
6,

BRIGHT MANUAL

7.

END

AUTO

not

4. Confirm noise does

5. Change the channel. confirm other channels
are ‘normal.

2-2-C:

TINT

1.

Receive the color bar patter”.

2. Using the remote Control. set the brightness
and color to center position.

3. Using the remote control, set the contrast
to

maxlmum

4. Connect the

5. Activate the adjustment mode display and press
the 5 key.

6. Press the VOL. UP/DOWN key a” the remote
Control
Fig.

2-4

position.

oscilloscope

until

the waveform becomes as show” in

appear,

to TPO23.

I

c

2-2-A:

1. Receive the monochrome pattern

2. Activate the adiustment mode display and press

3. Press the VOL. UP/DOWN key on the remote

2-2-B.
NOTE

In case of weak electric field.

1. Tune to a noisy channel.

2. Activate the adjustment mode display and press

3. Press the VOL. UP/DOWN key a” the remote control

4. Change the channel. confirm other channels

I” case of strong electric field.
(Radio frequency interlerence can cause diagonal

1. Aclivate the adjustment mode display and press

2.

3. If there is still a problem after pressing the VOL.

BRIGHT

the 6 key.
control until 0% of gray scale will begins to lighten.

AGC

Adjust after performing adjustments in section 2-l

the 3 key.
until noise is at minimum.
are normal.

streaks to appear.)

the 3 key.
Press

the VOL. UP/DOWN key on the remote

control

until diagonal streaks are at minimum.

UP/DOWN key
an attenuator to
repeat step

on

the remote control. install

the

antenna

1.

terminals

Fig. 2-3

the”

2-2-D: COLOR

1.

Receive the color bar patter”,

2. Using the remote control, set the brightness
and tint to center position.

3. Using the remote control, set the contrast

maximim position

to

4. Connect the oscilloscope to

5. Activate the adjustment mode display and
the 4 key.

6. Adjust the VOLTS RANGE VARIABLE knob of
the oscilloscope until the range between

100%

and 0% is set to 5 scales a” the Screen

Ihe

oscilloscope.

of

7. Press the VOL. UP/DOWN key
control until the red color level is set to

the

4.75th

scale (95%) from while 0%.

(Refer

to Fig. 2-5)

TP022.

on

white

the remote

Fig. 2.5

press

4

ELECTRICAL

ADJUSTMENTS

4. Confirm red

5. Adjust

watching the

/

/

3-3:

STATIC CONVERGENCE

NOTE

Adjust after performing adjustmenls in section 3-2.

1. Receive the crosshatch pattern from
generator.

2. Combine red and blue of ‘the 3
pattern on the center of the screen by adjusting
the pair of 4 pole magnets.

3. Combine red/blue (magenta) and green by
adjusting the pair of 6 pole magnets.

the slant

and

blue

of

screen.

colors

Ihe

deflection yoke while

then

tighten

the fixing screw.

MAGNET

6 POLE MAGNETS

-

I

Fig.

4 POLE MAGNETS

PURITY MAGNETS

3-1

color

color

crosshatch

bar

SCREW

WEDGE

WEDGE

(

WEDGE POSITION

Fig. 3-2-b

WEDGE

3-4: DYNAMIC CONVERGENCE
NOTE

Adjust after performing adjustments in section 3-3.

1. Adjust the differences around the screen by moving

the deflection yoke upward/downward and

right/left. (Refer to Fig. 3-2-a)

2. Insert three wedges between the deflection yoke

and CRT funnel to fix the deflection yoke.
(Refer to Fig. 3-2-b)

Fig. 3-2-e

ELECTRICAL ADJUSTMENTS

2-3: CUT OFF

1. Receive the color bar petter”.

2. Using the remote control. set brightness and
contrast to

3. Connect the oscilloscope to

4. Adjust the screen control until voltage is 150VOC.
(Refer to Fig. 2-6)

minimum

ON”

position.

--

,TPO24.

jiO”

Fig. 2-f

NOTE

Lessen the value of R444......Picture will move right.

Lessen the value of
R444

and

C460
resistor or capacitor to determine the optimal value
and insert that value component.

3.

PURITY

AND

C460 ,...,.Picture

are fixed components. Use a variable

will move left.

CONVERGENCE

ADJUSTMENT

NOTE

1. Turn the unit on and let it warm up for at
least

30 minutes before performing the

adjustments.

2. Place the CRT surface facing east or west to

reduce the terrestrial magnetism.

3. Turn ON the unit and demagnetize

degauss Coil,

followiiig

with

a

2-4: FOCUS

1. Receive the broadcasting signal.

2. Adiust the locus control until picture is distinct
2-5: VERTICAL SIZE

1. Receive the crosshatch petter” from the color
bar generator.

2. Adjust the bright and contrast controls until
the

crosshatch patter” is distinct.

3. Adjust VA401 until the center of crosshatch
is square.

4. Receive broadcasting signal, the” confirm
picture is

2-6: VERTICAL POSITION

1,

Receive the color bar patter”.

2. Using the remote control. set brightness and
Contrast Lo maximum position.

3. Adjust the value of A429 and
line of the color bar comes to approximate center
of the CRT.

NOTE

Lessen the value of R430......Picture will move about

Lessen the value of R429.....Picture will move about

R429 and R430 are fixed resistors. Use a variable
resistor to determine the optimal value and insert
that value resistor.

2-7:

Receive the color bar patter”.
Using

contrast to maximum position.
Adjust the value of
of both
Receive
picture

normal.

R430

until horizontal

5mm

UP.

5mm

DOWN.

HORIZONTAL POSITION

the remote control. set brightness and

R444

and

C460

until the color width

screen

edges are equal.

the broadcasting signal, the” confirm

is

normal.

3-1: STATIC CONVERGENCE (ROUGH

1. Tighten the screw for the magnet. Refer to the
adjusted

(Refer

If the deflection yoke and magnet are in one
body, untighten the screw for

2. Receive the green
bar generator.

3.

Slide the deflection yoke until it touches

funnel side of

4. Adjust center of screen to green. with red
and blue a” the sides, using the pair
purity magnets.

5. Switch the color bar generator from the
raster patter” to, the crosshatch

6. Combine red
Patter” on the
the pair of

7. Combine red/blue (magenta) and green by
adjusting the pair of 6 pole magnets.

8. Adjust the crosshatch petter” to change to

white by repeating steps 6 and 7.

3-2:
NOTE

Adjust after; performing adjustments in section 3-1
Receive

generator.
Adjust the pair of purity magnets to center
color on the screen.
Adjust the pair of purity magnets so the color
at ends are equally wide.

Move the deflection yoke backward (to
side) slowly, and Stop it at the position
the whole screen is green.

to

PURITY

CRT

for the position.

Fig. 3-1)

the

CRT.

and

center

4

pole magnets.

the green

raster petter” from color bar

the

raster

patter” from

pattern.

blue of the 3

of the screen by adjusting

ADJUSTMENT

body.

color

the

of

green

color crosshatch

the

neck

when