Orion TC1973D Service Manual

COLOR TELEVISION RECEIVER

TC1973D

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1

SPECIFICATIONS

1

UHF
CATV

All the specifications and features are subject to change without notice.

DISASSEMBLY INSTRUCTIONS

1. REMOVAL OF ANODE CAP

Read the following NOTED items before starling work.

After turning the power off there might still be a potential
voltage that is very dangerous. When removing the
Anode Cap, make sure to discharge the Anode Cap’s
potential voltage.

’

Do not use pliers to loosen or tighten the Anode Cap
terminal, this may cause the spring to be damaged.

REMOVAL

1.

Follow the steps as follows to discharge the Anode Cap.

(Refer to Fig. l-l.)

Connect one end of an Alligator Clip to the metal part of a

flat-blade

screwdriver and the other end to ground.
While holding the plastic part of the insulated Screwdriver,
touch the support of the Anode with the tip of the
Screwdriver.
A cracking noise will be heard as the voltage is discharged.

GND

on the CRT

GND on the CRT

Fig. 1-l

2. Flip up the sides of the Rubber Cap in the direction

of

the
arrow and remove one side of the support
(Refer to Fig. l-2.)

Rubber Cap

CRT

V

Support

Fig.

1-2

3. After one side is removed. pull in the opposite direction to
remove the other.

NOTE

Take care not to damage the Rubber Cap.

INSTALLATlON

1. Clean the spot where the cap was located with a small

amount of alcohol. (Refer to Fig. l-3.)

NOTE

Confirm that there is no dirt. dust, etc. at the spot where
the cap was located.

2. Arrange the wire of the Anode Cap and make sure the
wire is not twisted.

3. Turn over the Rubber Cap. (Refer to Fig. l-4.)

Fig. 1-4

4

DISASSEMBLY INSTRUCTIONS

4,

Insert one end of the Anode Support into the anode button.

then the other as shown in Fig. I-5.

Fig.

l-

5. Confirm that the Support is securely connected.

6. Put on the Rubber Cap without moving any parts.

2. REMOVAL OF DEFLECTION YOKE
(Refer to

Fig. 2-1)

I.

Loosen the screw

0.

2. Remove the Convergence . Purity Magnet in the

direction of arrow (A).

3. Loosen the screw

0.

4. Remove the 3 Wedges.

5. Remove the Dellection Yoke in the direction of
arrow

(8).

INSTALLATION

tnstall new Deflection Yoke in reverse steps of REMOVAL.

NOTE

After adjusting the purity and the convergence. fix the
screw 0 and lock the wedges.

Wedge

Fig.

2-.

5

ELECTRICAL ADJUSTMENTS

1. BEFORE MAKING ELECTRICAL
ADJUSTMENTS

Read and perform these adjustments when repairing the
circuits or replacing electrical parts or

PC6

assemblies.

CAUTION

Use an isolation transformer when performing any

sarvce

on this chassis.

1.

CUTOFF

2.

VSIZE

3.

BRI.

AUTO

4.

X-RAY

5.

CONT

8.

END

Before removing the anode cap, discharge electricity

because it contains high voltage.

When removing a PCB or related component, after
unfastening or changing a wire, be sure to put the wire
back in its original position.

Inferior

sillcon

grease can damage

IC’s

and transistors.

When replacing

IC’s

and transistors. use only specified

silicon grease

(YG6260M).

Remove all old silicon before applying new silicon.

1-l: Prepare the following measurement tools far

electrical adjustments.

1.

Sweepmarker Generator

2. Oscilloscope

3. Digital Voltmeter

4. Color Bar Generator

L

Fig.

2-Z

1.

AUTO

2. vco

3. AFT

4. AGC

5. COL

6. TINT

7.

BRI

8. END

2. BASIC ADJUSTMENTS

Fig. 2-3

On-Screen Display Adjustment

the of a straightened paper clip into the hole

on remote control marked with an arrow as shown

2-1: VCO AND AFT
NOTE

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

in Fig.

2-4-a,

it.

Fig. 2-f.

The adjustment mode display will appear as shown

Fig.2-2 andFig.2.3.

NOTE

Use the

1 8

keys on the remote control to select the

options shown in Fig. 2-2 and Fig. 2-3.

Press the 8 key to end the adjustments.

Fig. 2-l

SWEEPMAKER
GENERATOROUTPUT

0.22

rF

-

GND
SWEEPMAKER
GENERATOR INPUT 47Kohm

lN60 4.5 pF

Fig. 2-4-z

1.

Connect output terminal of

Ihe

sweepmarker generator to

TP201.

2. Connect input terminal of the sweepmarker generator to
TP204.

3. Connect a

10K

ohm variable resistor to IF AGC terminal

(TP210). 12V

line and ground. lhen adjust to make the

wavelorm 01 the oscilloscope readable

3

,

f

.

ELECTRICAL ADJUSTMENTS

10

Kohm

AGC TP210

4. Activate the adjustment mode display (Fig.

2-3)

and

press the 2 key.

5. Adjust VOL. UP/DOWN key on the remote control until
the waveform maker

(45.75MHz)

becomes as shown in

Fig. 2-4-b.

6.

7.

6.

9.

45.75 MHz

x

Fig. 2-4-t

_

Disconnect output terminal 01 the sweepmarker generator

from

TP201,

then connect it to TP al the tuner pack.

Disconnect the

10K

ohm and the

2.7K

ohm variable

resistors.

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

(45.75MHz)

to TP of the tuner pack.

1 O.Connect the digital voltmeter to TP206.
1

l.Activate

the adjustment

mode

display (Fig. 2-3) and press

the 3 key.

12.Adjust

VOL. UP/DOWN key on the remote control to find

the point where the voltage of

TP206

changes dramatically,

and adjust to

4.5VDC

at that point.

2-2: BRIGHT, AGC, TINT AND COLOR
2-2-A: BRIGHT

1.

Receive the monochrome pattern.

2. Activate the adiustment mode displav

(Fig. 2-3)

and

press the 7

ke;.

,.

”

3. Press the VOL. UP/DOWN key on the remote control
until the boundary between 0% and 10% white starts
to become visible.

2-2-B: AGC
NOTE

Adjust after performing adjustments in section 2-1.

In case of weak electric field.

1. Tune to a noisy channel.

2. Activate the adjustment mode display and press
the 4 key.

3. Press the VOL. UP/DOWN key on the remote control
until noise is at minimum.

4.

Change the channel. confirm that the other channels
are normal.

In case of strong electric field.
(Radio frequency interference can

cause

diagonal

streaks to appear.)

1. Activate the adjustment mcde display and press

rhe

4

key.

2.

Press the VOL. UP/DOWN key 0” the remote

control untit

diagonal streaks are at minimum.

3. If there is still a problem after pressing the VOL. UP/DOWN
key on the remote control. install an attenuator to the

antenr,

terminals. then repeat step

1.

4. Confirm that noise does not appear.

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

2-2-C: TINT

1.

Receive the color bar pattern.

2. Connect the oscilloscope to TP023.

3. Activate the adjustment

mode

display (Fig. 2-3) and press

the 6 key.

4. Press the VOL. UP/DOWN key on the remote control

until

the waveform becomes as shown in Fig.

2-5.

1

I

Fig.

2i

2-2-D: COLOR

1.

Receive the color bar pattern.

2. Connect the oscilloscope to TP022

3. Activate the adjustment mode (Fig. 2-3) display and press
the 5 key.

4. Adjust the VOLTS RANGE VARIABLE knob of the
oscilloscope until the range between white 0% and 1 CO%
is set to 5 scales on the screen of the oscilloscope.

5. Press the VOL. UP/DOWN key an the remote control

untii

the red color level is adjusted to

4.75scalesf95%1

for

:he

white level. (Refer to Fig. 2-6)

I

b+4

I

I

95%

LL

h-

J

--OX

k

I-_-_-

--

100%

7

ELECTRICAL ADJUSTMENTS

2-3: CUT OFF

1.

Receive the color bar pattern.

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

mm~mum

position.

3. Connect the oscilloscope to TP024.

4. Adjust the

screen

volume until voltage is

15OVDC.

(Refer to Fig. 2-7)

---­.

.

.-

--

*

.

.

.

I

DC1

50V

GND-

Fig.

2-

2-4: FOCUS

1.

Receive

the broadcasting signal.

2. Adjust the focus control until picture is distinct
2-5: VERTICAL SIZE

1.

Receive the crosshatch pattern

lrom

the color bar generator.

2. Activate the adjustment mcde display (Fig.

2-2)

and press

the 2 key.

3. Press the VOL. UP/DOWN key on the remote control until
the horizontal

overscan

is equal to the vertical

averscan.

2-6: VERTICAL POSITION

1. Receive the color bar pattern.

2.

Using the remote control, set brightness and contrast to
maximum position.

3. Adjust the value of R429 and R430 until horizontal line of
the color bar comes to approximate center of the CRT.

NOTE

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

value resistor.

Lessen the value of R430

Picture will

move

about

5mm UP.

Lessen the value 01 R429

Picture will move about
5mm DOWN.

2-7: HORIZONTAL POSITION

1.

Receive the color bar pattern.

2. Adjust the value 01 R443 and

C460

until the color width

01

both screen edges are equal.

3. Receive the broadcasting signal, then confirm picture is

normal.

NOTE

R443 and

C466

are fixed components. Use a variable
resistor or capacitor to determine the optimal value and
insert that value component.

Lessen the value of R443

Picture

will move right.

Lessen the

value 01

C460

Picture Will move left.

8

I

1

7

I

ELECTRICAL ADJUSTMENTS

3. PURITY AND CONVERGENCE
ADJUSTMENT

NOTE

1. Turn the unit on and let it warm up

for

at least 30

minutes before performing the following adjustments.

2. Place the CRT surface lacing east or west to reduce the
terrestrial magnetism.

3. Turn ON the unit and demagnetize with a

Degauss

Coil.

3-I: STATIC CONVERGENCE (ROUGH ADJUSTMENT)

1.

Tighten the

xrew

for the magnet. Refer to the adjusted

CRT for the position. (Refer to Fig.

3-l)

If the deflection yoke and magnet are in one body,

untighten

the screw for the body.

2. Receive the green raster pattern from color bar
generator.

3. Slide

the

deflection yoke until it touches the funnel

side 01 the CRT.

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

5. Switch the color bar generator from the green raster
pattern to the crosshatch pattern.

6. Combine red and blue of the 3 color crosshatch pattern

on the center ol the screen by adjusting the pair of
4 pole magnets.

7. Combine red/blue (magenta) and green by adjusting the

pair of 6 pole magnets.

6. Adjust the crosshatch pattern to change to white

by repeating steps 6 and 7.

3-2:

PURITY

NOTE

Adjust after performing adjustments in section 3-1.

1.

Receive the green raster pattern from color bar

generatar.

2. Adjust the pair of purity magnets to center the

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

3. Move the deflection yoke backward (To neck side)
slowly. and stop it at the position when the whole
screen IS green.

4. Confirm red and blue colors.

5~

Adjust the slant of the deflection yoke while watching the

screen. then tighten the fixing screw.

DEFLECTION YOKE
DEFLECTION YOKE SCREW
MAGNET SCREW

PURITY MAGNETS
6 POLE MAGNETS

4 POLE MAGNETS

Fig.

3-l

3-3:

STATIC CONVERGENCE

NOTE

1. Receive the crosshatch pattern lrom color bar generator.

2. Combine red and blue of the 3 color crosshatch 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.

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

lix

the deflection yoke.

(Refer to Fig. 3-2-b)

UPWARD/DOWNWARD SLANT

RIGHT/LEFT SLANT

Fig. 3-2-a

\

0

/

NEDGE

WEDGE

WEDGE

WEDGE POSITION

Fig. 3-2-b

9