SAMSUNG CT566BVX-STR, CT566BVX-XAP, CT566BWX-STR, CT567BWX-STR, CT567BWX-XAP Service Manual

...

0 (0)

SAMSUNG CT566BVX-STR, CT566BVX-XAP, CT566BWX-STR, CT567BWX-STR, CT567BWX-XAP Service Manual

COLOR TELEVISION RECEIVER

Chassis :	KCT57A
Model:	CT566BVX/STR
	CT566BVX/XAP
	CT566BWX/STR
	CT567BWX/STR
	CT567BWX/XAP
	CT766DWX/STR
	CT766DWX/XAP

COLOR TELEVISION RECEIVER		CONTENTS
1.		Precautions
2.		Specifications and IC Data
3.		Alignment and Adjustment
4.		Tr oubleshooting
5.		Exploded View and Parts List
6.		Electric Parts List
7.		Block Diagram
8.		PCB Layout Diagram
9.		Wiring Diagram
10.		Schematic Diagrams

Precautions

1. Precautions

Follow these safety, servicing and ESD precautions to prevent damage and protect against potential hazards such as electrical shock and X-rays.

1-1 Safety Precautions

1.Be sure that all of the built-in protective devices are replaced. Restore any missing protective shields.

2.When reinstalling the chassis and its assemblies, be sure to restore all protective devices, including: nonmetallic control knobs and compartment covers.

3.Make sure that there are no cabinet openings through which people—particularly children—might insert fingers and contact dangerous voltages. Such openings include the spacing between the picture tube and the cabinet mask, excessively wide cabinet ventilation slots, and improperly fitted back covers.

If the measured resistance is less than 1.0 megohm or greater than 5.2 megohms, an abnormality exists that must be corrected before the unit is returned to the customer.

4.Leakage Current Hot Check (Figure 1-1): Warning: Do not use an isolation transformer during this test. Use a leakagecurrent tester or a metering system that complies with American National Standards Institute (ANIS C101.1, Leakage Current for Appliances), and Underwriters Laboratories (UL Publication UL1410, 59.7).

5.With the unit completely reassembled, plug the AC line cord directly into the power outlet. With the unit’s AC switch first in the ON position and then OFF, measure the current between a known earth ground (metal water pipe, conduit, etc.) and all exposed metal parts, including: antennas, handle brackets, metal cabinets, screwheads and control shafts. The current measured should not exceed 0.5 milliamp. Reverse the powerplug prongs in the AC outlet and repeat the test.

				(READING SHOULD
				(READING SHOULD
			LEAKAGE	NOT BE ABOVE
DEVICE			CURRENT		0.5mA)
UNDER			TESTER
TEST
TEST

		TEST ALL
	EXPOSED METAL
		SURFACES
2-WIRE CORD
ALSO TEST WITH
PLUG REVERSED
(USING AC ADAPTER						EARTH
PLUG AS REQUIRED)					GROUND

Fig. 1-1 AC Leakage Test

6.Antenna Cold Check:

With the unit’s AC plug disconnected from the AC source, connect an electrical jumper across the two AC prongs. Connect one lead of the ohmmeter to an AC prong. Connect the other lead to the coaxial connector.

7.X-ray Limits:

The picture tube is especially designed to prohibit X-ray emissions. To ensure continued X-ray protection, replace the picture tube only with one that is the same type as the original. Carefully reinstall the picture tube shields and mounting hardware; these also provide X-ray protection.

8.High Voltage Limits:

High voltage must be measured each time servicing is done on the B+, horizontal deflection or high voltage circuits. Correct operation of the X-ray protection circuits must be reconfirmed whenever they are serviced. (X-ray protection circuits also may be called “horizontal disable” or “hold-down”.)

Heed the high voltage limits. These include the X–ray Protection Specifications Label, and the Product Safety and X-ray Warning Note on the service data schematic.

Samsung Electronics

1-1

Precautions

1-1 Safety Precautions (Continued)

9.High voltage is maintained within specified limits by close-tolerance, safety-related components and adjustments. If the high voltage exceeds the specified limits, check each of the special components.

10.Design Alteration Warning:

Never alter or add to the mechanical or electrical design of this unit. Example: Do not add auxiliary audio or video connectors. Such alterations might create a safety hazard. Also, any design changes or additions will void the manufacturer’s warranty.

11.Hot Chassis Warning:

Some TV receiver chassis are electrically connected directly to one conductor of the AC power cord. If an isolation transformer is not used, these units may be safely serviced only if the AC power plug is inserted so that the chassis is connected to the ground side of the AC source.

To confirm that the AC power plug is inserted correctly, do the following: Using an AC voltmeter, measure the voltage between the chassis and a known earth ground. If the reading is greater than 1.0V, remove the AC power plug, reverse its polarity and reinsert. Re-measure the voltage between the chassis and ground.

12.Some TV chassis are designed to operate with 85 volts AC between chassis and ground, regardless of the AC plug polarity. These units can be safely serviced only if an isolation transformer inserted between the receiver and the power source.

13.Some TV chassis have a secondary ground system in addition to the main chassis ground. This secondary ground system is not

isolated from the AC power line. The two ground systems are electrically separated by insulating material that must not be defeated or altered.

14.Components, parts and wiring that appear to have overheated or that are otherwise damaged should be replaced with parts that meet the original specifications. Always determine the cause of damage or overheating, and correct any potential hazards.

15.Observe the original lead dress, especially near the following areas: Antenna wiring, sharp edges, and especially the AC and high voltage power supplies. Always inspect for pinched, out-of-place, or frayed wiring. Do not change the spacing between components and the printed circuit board. Check the AC power cord for damage. Make sure that leads and components do not touch thermally hot parts.

16.Picture Tube Implosion Warning:

The picture tube in this receiver employs “integral implosion” protection. To ensure continued implosion protection, make sure that the replacement picture tube is the same as the original.

17.Do not remove, install or handle the picture tube without first putting on shatterproof goggles equipped with side shields. Never handle the picture tube by its neck. Some “in-line” picture tubes are equipped with a permanently attached deflection yoke; do not try to remove such “permanently attached” yokes from the picture tube.

18.Product Safety Notice:

Some electrical and mechanical parts have special safety-related characteristics which might not be obvious from visual inspection. These safety features and the protection they give might be lost if the replacement component differs from the original—even if the replacement is rated for higher voltage, wattage, etc.

Components that are critical for safety are indicated in the circuit diagram by shading,

( ) or ( ! ).

Use replacement components that have the same ratings, especially for flame resistance and dielectric strength specifications.

A replacement part that does not have the same safety characteristics as the original might create shock, fire or other hazards.

1-2	Samsung Electronics

Precautions

1-2 Servicing Precautions

Warning1: First read the “Safety Precautions” section of this manual. If some unforeseen circumstance creates a conflict between the servicing and safety precautions, always follow the safety precautions.

Warning2: An electrolytic capacitor installed with the wrong polarity might explode.

1.Servicing precautions are printed on the cabinet. Follow them.

2.Always unplug the unit’s AC power cord from the AC power source before attempting to: (a) Remove or reinstall any component or assembly, (b) Disconnect an electrical plug or connector, (c) Connect a test component in parallel with an electrolytic capacitor.

3.Some components are raised above the printed circuit board for safety. An insulation tube or tape is sometimes used. The internal wiring is sometimes clamped to prevent contact with thermally hot components. Reinstall all such elements to their original position.

4.After servicing, always check that the screws, components and wiring have been correctly reinstalled. Make sure that the portion around the serviced part has not been damaged.

5.Check the insulation between the blades of the AC plug and accessible conductive parts (examples: metal panels, input terminals and earphone jacks).

6.Insulation Checking Procedure: Disconnect the power cord from the AC source and turn the power switch ON. Connect an insulation resistance meter (500V) to the blades of the AC plug.

The insulation resistance between each blade of the AC plug and accessible conductive parts (see above) should be greater than 1 megohm.

7.Never defeat any of the B+ voltage interlocks. Do not apply AC power to the unit (or any of its assemblies) unless all solid-state heat sinks are correctly installed.

8.Always connect a test instrument’s ground lead to the instrument chassis ground before connecting the positive lead; always remove the instrument’s ground lead last.

Samsung Electronics

1-3

Precautions

1-3 Precautions for Electrostatically Sensitive Devices (ESDs)

1.Some semiconductor (“solid state”) devices are easily damaged by static electricity. Such components are called Electrostatically Sensitive Devices (ESDs); examples include integrated circuits and some field-effect transistors. The following techniques will reduce the occurrence of component damage caused by static electricity.

2.Immediately before handling any semicon ductor components or assemblies, drain the electrostatic charge from your body by touching a known earth ground. Alternatively, wear a discharging wrist-strap device. (Be sure to remove it prior to applying power— this is an electric shock precaution.)

3.After removing an ESD-equipped assembly, place it on a conductive surface such as aluminum foil to prevent accumulation of electrostatic charge.

4.Do not use freon-propelled chemicals. These can generate electrical charges that damage ESDs.

5.Use only a grounded-tip soldering iron when soldering or unsoldering ESDs.

6.Use only an anti-static solder removal device. Many solder removal devices are not rated as “anti-static”; these can accumulate sufficient electrical charge to damage ESDs.

7.Do not remove a replacement ESD from its protective package until you are ready to install it. Most replacement ESDs are packaged with leads that are electrically shorted together by conductive foam, aluminum foil or other conductive materials.

8.Immediately before removing the protective material from the leads of a replacement ESD, touch the protective material to the chassis or circuit assembly into which the device will be installed.

9.Minimize body motions when handling unpackaged replacement ESDs. Motions such as brushing clothes together, or lifting a foot from a carpeted floor can generate enough static electricity to damage an ESD.

1-4	Samsung Electronics

Specifications and IC Data

2. Specifications and IC Data

2-1 Specifications


Model	CT566BV		CT566BW/567BW/568BW	CT633BW	CT683BW	CT766DW

Television System :	NTSC-M

Channels :	VHF : CH 2 ~ CH 13
	UHF : CH 14 ~ CH 69
	CATV : CH 1, CH 14 ~ CH 125

	Picture IF Carrier : 45.75 MHz
Intermediate Frequencies :	Sound IF Carrier : 41.25 MHz
	Color Sub Carrier : 42.17 MHz

Sound System	MONO			MTS

Picture Tube :		A53QCX89X01		A63AFW32X	A68ADT25X01	A70QBZ791X

Power Requirements :	AC100~240V, 50/60Hz

Antenna Input Impedance :	75 ohm unbalanced type

Speaker Impedance :	8 ohm, 3W + 3W

Protection :	X-Ray Protection, Fail Safe Circuit

Samsung Electronics

2-1

Specifications and IC Data

2-2 IC Line Up

Table 2 - 1 IC Line - Up

Loc No

Specification

Description

Remarks

SF101

M3951M

SAW FILTER (VIF)

SF102

M9260M

SAW FILTER (SIF)

TDA8377

ONECHIP TV PROCESSOR

CT566BV/CT567BW/CT568BW/CT766DW

IC201

TDA8373

ONECHIP TV PROCESSOR

CT633BW/CT683BW

IC202

LA7510

AUDIO IF AMP/4.5M DETECT

IC301

TDA8350Q

VERTICAL AMP IC

IC603

TDA7057AQ

SOUND AMP IC

IC602

μPC 1460HA

VOLUME CONTROL IC

STEREO MODEL ONLY

IC701

TDA4053

SWITCHING IC

STEREO MODEL ONLY

S6709

CT633BW/CT683BW/CT766DW

IC801

POWER IC

STR5707

CT566BV/CT566BW/CT567BW/CT568BW

IC802

KA7630

MULTI REGULATOR IC

IC901

SZM322

MICOM

IC902

XL24C02P

EEPROM

ICD01

TDA9850

MTS IC

STEREO MODEL ONLY

2-2	Samsung Electronics

Specifications and IC Data

2-3 Semiconductor Base Diagrams

ELECTROLYTIC-

CONDENSER

TRANSISTOR

KSC2073

KSA940

2SD1887

2SD1880

KSD5072

DIODE

TRANSISTOR

KSC815Y

KSA539-Y

E B C

TRANSISTOR

TDA8133

TDA8356

KA7812

KA7809

XLS24C02P (PIN 8)

TDA8375 (PIN 56)

RM168E (PIN 42)

TDA9850 (PIN 22)

TDA4053 (PIN 16)

SAW-FILTER

M3951M

M9260M

TRANSISTOR

C2331-Y

KSR1010

G	E C B
out

Fig. 2-1 Semiconductor Base Diagrams

Samsung Electronics

2-3

Specifications and IC Data

2-4 One Chip TV-processor

SOUND IF INPUT

DECOUPLING SOUND DEMODULATOR

EXT AUDIO INPUT

AUDIO DEEMPHASSIS/MPX OUT

VCO REF FILTER

TUNER AGC OUTPUT

VCO REF FILTER

AGC DECOUPLING CAPACITOR

PLL LOOP FILTER

REREFERENCE CURRENT INPUT

IF VIDEO OUTPUT

VERT, SAWTOOTH CAPACITOR

EHT/OVERVOLTAGE PROTECTION INP

BUSINPUT : SCL

(X-RAY PROTECTION)

BUSINPUT : SDA

IF INPUT

BANDGAP DECOUPLING

IF INPUT

CHROMA INPUT

VERT. DRIVE NEG

Y/CVBS INPUT

VERT. DRIVE POS

MAIN POSITIVE SUPPLY

EAST-WEST DRIVE

INT CVBS INPUT

GROUND

PHI1 FILTER

AUDIO OUT

PHI2 FILTER / FLASH PROT

DECOUPLING FILTER TUNING

SAND CASTLE OUTPUT/FLYBACK INP

EXT CVBS INPUT

HOR. OUTPUT

BLACK CURRENT INP

BLACK PEAK HOLD CAPACITOR

BLUE OUTPUT

CVBS OUTPUT

GREEN OUTPUT

POSITIVE SUPPLY

RED OUTPUT

LOOP FILTER BURST PHASE DET

V-GUARD INP/BEAM CUR LIMITER

X-TAL (PAL-N (4.43)/PAL-M (3.58))

RED INPUT

X-TAL (3.58)

GREEN INPUT

SECAM REF OUTPUT

(R-Y) INPUT

BLUE INPUT

(B-Y) INPUT

PIP/OSD RGB INSERTION SWITCH INP

LUMINANCE INPUT

(R-Y) OUTPUT

SDIL56

LUMINANCE OUTPUT

(B-Y) OUTPUT

Fig. 2-2 SDIL56

CVBS : Composite Video Blanking Signal

2-4	Samsung Electronics

Alignment and Adjustments

3. Alignment and Adjustments

3-1 Preadjustment

1.Since there are no VRs in the KCT52A chassis, all adjustments after parts replacement must be done in the Service Mode.

2.The Factory Mode adjustments are necessary when either the EEPROM (IC902) or the CRT is replaced.

3.Do not tamper with the “ Adjustment” screen of the Factory Mode menu. This screen is intended only for factory use.

4. WHEN EEPROM (IC902) IS REPLACED

(1)When IC902 is replaced, all adjustment data revert to their initial values. It is necessary to re-program this data.

(2)After IC902 is replaced, warm up the TV for 10 seconds.

Make the following adjustments AFTER setting up purity and convergence:

White Balance Sub-Brightness Vertical Center Vertical Size

Horizontal Size (No use in 21” and 25” models)

3-2 Factory (“SERVICE”) Mode

1.The set must be in Factory (“Service”) Mode. Selection sequence:

STAND-BY → MUTE → 1 → 8 →2→POWER ON

2.The “ FACTORY MODE” message will be displayed. The Factory Mode has four components : Adjustment, Test Pattern, Set Option Byte, and Factory Reset.

3. Access the Adjustment Mode by pressing the “VOLUME” keys (▼ , ▼) The adjustment parameters are listed in the accompanying table. Select them by pressing the CHANNEL keys (▲,▼).

4.After completing the Factory Mode adjustments, turn the power switch OFF.

Samsung Electronics

3-1

Alignment and Adjustments

3-2-1 Adjustment

1.Selection sequence :

STAND-BY → MUTE → 1 → 8 → 2 → POWER ON

2.Example : Sub-bright Adjustment

*FACTORY MODE*

Adjustment

Mpx Adjust

Test Pattern

Set Option Byte

Factory Reset

↓

AGC	15
VCO	62
SBT	7
SCT	11
SCR	8
STT	8
RG	32
GG	32
BG	32
SCO	20
VSL	26

↓

Press VOL

EWA

EWP

EWC

EWT

VZM

MAT

VOL

PLA

Press CH

▼

25 off 0 6

▼

AGC	15
VCO	62
SBT	7
SCT	11
SCR	8
STT	8
RG	32
GG	32
BG	32
SCO	20
VSL	26

↓

EWA

EWP

EWC

EWT

VZM

MAT

VOL

PLA

Press VOL

25 off 0 6

▼ or

▼

SB 3

↓

POWER OFF

3-2	Samsung Electronics

Alignment and Adjustments

MEMORY SPECIFICATION

Table 3 - 1 Memory Specification


FUNCTION	No	MODE		CT566BW/567BW/568BW			CT683BW
FUNCTION	No	MODE	CT566BV	CT566BW/567BW/568BW	CT766DW	CT633BW	CT683BW
		(OSD)

	1	AGC	15	15	15	15	15

	2	VCO	62	62	62	62	62

	3	SBT	7	7	7	7	7

	4	SCT	7	7	7	7	7

A	5	SCR	8	8	8	8	8

D	6	STT	8	8	8	8	8

J	7	RG	32	32	32	32	32

U	8	GG	32	32	32	32	32

S	9	BG	32	32	32	32	32

T	10	SCO	20	20	20	20	20

M	11	VSC	30	30	35	38	26

E	12	VS	32	32	32	32	32

N	13	VA	7	7	15	45	27

T	14	HS	42	42	48	46	46

	15	EWA	38	38	38	52	52

	16	EWP	0	0	49	31	31

	17	EWC	0	0	32	32	32

	18	EWT	31	31	31	31	31

	19	VZM	25	25	25	25	25

	20	MAT	off	off	off	off	off

	21	VOL	0	0	0	0	0

	22	PLA	6	6	6	0	0

	1	ST	15	7	7	7	7

	2	SP	15	7	7	7	7

M	3	LEV	15	9	9	9	9

P	4	AL1	31	20	20	20	20

X	5	AL2	31	10	10	10	10

	6	AL3	7	0	0	0	0

	7	ADJ	on/off	off	off	off	off

	1	BYTE 0	A4	84	84	84	84
OPTION
OPTION	2	BYTE 1	20	60	70	50	50
	2	BYTE 1	20	60	70	50	50

Samsung Electronics

3-3

Alignment and Adjustments

3-2-2 Test Pattern (Aging Mode)

1.This mode can be used to confirm that the convergence and purity adjustments are correct.

2.Access the Test Pattern parameters by pressing the CHANNEL keys (▲,▼) while the Service Mode is on. The cursor will move to the test pattern. Press the VOLUME keys. On-screen display:

RED

GREEN

BLUE

3-2-3 V2 Tri-Norma Option Table

3-2-3(A) OPTION BYTE 0

Table 3-2 Option Byte 0

DATA

FUNCTION

REMARK

= AIR/STD/HRC/IRC

OPTION

= AIR/STD/HRC/AFN

= NORMAL

FIX = “0”

= NO SIGNAL REACH 20MIN AUTO POWER OFF

O = AUTO MUTE

FIX = “1”

= NO AUTO MUTE

= HELP OSD OK IN OTHER LANGEUAGE

FIX = “0”

= HELP OSD NO

OPTION BYTE 0

= NO AUTO POWER ON

FIX = “0”

= AUTO POWER ON

= MPX

OPTION

= NO MPX

= NON LINEAR SHARPNESS

FIX = “0”

= LINEAR SHARPNESS

= NR EXECUTE

FIX = “1 “

= NR SKIP

3-4	Samsung Electronics

Alignment and Adjustments

3-2-3(B) OPTION BYTE 1

Table 3-3 Option Byte 1

DATA

FUNCTION

REMARK

00 = TV/VIDEO

OPTION

01 = TV/VIDEO/S-VIDEO

11 = NO ASSIGNED

= VID : 0

FIX = “0”

= VID : 1

= RB 10 STEP UP

FIX = “0”

= RB 5 STEP UP

OPTION BYTE 1

= NO COMBFILTER

OPTION

= COMBFILTER

= 4 : 3 CRT

OPTION

= 12.8 : 9 CRT (Q MODEL)

= INTERNAL A/V SWITCH

OPTION (MONO = 0)

= EXTERNAL A/V SWITCH

OPTION (STEREO = 1)

NOT USED

Samsung Electronics

3-5

Alignment and Adjustments

3-2-4 Factory Reset

When “ Factory Reset” is selected, the User-Control data reverts to the initial values. The User-Control data is available at MENU (picture, sound and the other functions).

Note : When “ Factory Reset” is selected, the Factory Mode Data does not change.

Selection sequence :

Stand-By → MUTE → 1 → 8 → 2 → POWER ON

↓

* FACTORY MODE *

Adjustment

Mpx Adjust

Test Pattern

Set Option Byte

Factory Reset

↓ Press CH ▼

Adjustment

Mpx Adjust

Test Pattern

Set Option Byte

Factory Reset

↓ Press VOL ▼

Execute

3-3 Other Adjustments

3-3-1 General

1.Usually, a color TV needs only slight touch-up adjustment upon installation. Check the basic characteristics such as height, horizontal and vertical sync and focus.

2.Observe the picture for good black and white details. There should be no objectionable color shading. If color shading is present, perform the purity and convergence adjustments described below.

3.Use the specified test equipment or its equivalent.

4.Correct impedance matching is essential.

5.Avoid overload. Excessive signal from a sweep generator might overload the front-end of the TV. When inserting signal markers, do not allow the marker generator to distort test results.

6.Connect the TV only to an AC power source with voltage and frequency as specified on the backcover nameplate.

7.Do not attempt to connect or disconnect any wires while the TV is turned on. Make sure that the power cord is disconnected before replacing any parts.

8.To protect against shock hazard, use an isolation transformer.

3-6	Samsung Electronics

3-3-2 Automatic Degaussing

A degaussing coil is mounted around the picture tube, so external degaussing after moving the TV should be unnecessary. However, the receiver must be properly degaussed upon installation.

The degaussing coil operates for about 1 second after the power is switched ON. If the set has been moved or turned in a different direction, disconnect its AC power for at least 10 Minutes.

If the chassis or parts of the cabinet become magnetized, poor color purity will result. If this happens, use an external degaussing coil. Slowly move the degaussing coil around the faceplate of the picture tube and the sides and front of the receiver. Slowly withdraw the coil to a distance of about 6 feet before removing power.

3-3-3 High Voltage Check

CAUTION : There is no high voltage adjustment on this chassis. The B+ power supply must be set to either +135V or +125V (for 20” screen). Conditions : Full color bar input and normal picture level.

1.Connect a digital voltmeter to the second anode of the picture tube.

2.Turn on the TV. Set the Brightness and Contrast controls to minimum (zero beam current).

3.The high voltage must not exceed 29.5KV.

4.Adjust the Brightness and Contrast controls to both extremes. Ensure that the high voltage does not exceed 29.5KV under any conditions.

SIZE	21”+ 1	25”	29”	29” + 1
MAX	27.5KV	29.5KV	29.5KV	29.5KV

H-VOLTAGE

Alignment and Adjustments

3-3-4 FOCUS Adjustment

1.Input a black and white signal.

2.Adjust the tuning control for the clearest picture.

3.Adjust the FOCUS control for well defined scanning lines in the center area of the screen.

3-3-5 B + Line Check

There are 3 power modes :

1.“A” : When AC power supply is connected ; “ Stand-By” mode.

2.“B” : When “ Set Power-ON” button is pressed.

3.“C” : Driven by FBT.

Each voltage is marked on its lead-in wire.

(

)

3-3-6 F/S (Fail Safe) Circuit Check

1.The failsafe circuit check is the final step after servicing.

2.Turn the power switch on and adjust the screen for “Normal”.

3.Temporarily short Pin R and Pin X on the chassis (RX05, RX04). Sound and picture will disappear.

4.The TV should remain in this state. This shows that the failsafe circuit is working properly.

5.To restore picture and sound, temporarily turn off the AC power supply. After about 30 seconds, switch power ON.

Samsung Electronics

3-7

Alignment and Adjustments

3-3-7 Color Purity Adjustment

1.Warm up the receiver. Operate it for 20 minutes, with the Brightness control set to maximum.

2.Fully degauss the receiver. Use an external degaussing coil.

3.Roughly adjust convergence by rotating the Convergence Magnet.

4.Input a black and white signal.

5.Loosen the Deflection Yoke clamp screw, and move the Deflection Yoke as close to the purity magnet as possible.

6.Loosen the Purity Magnet clamp. Adjust the purity magnet so that the vertical green raster is precisely at the center of the screen. Then tighten the clamp.

7.Slowly move the Deflection Yoke forward, and adjust it for the best overall green screen.

8.Tighten the Deflection Yoke clamp screw.

	DEFLECTION
	YOKE
CRT	PURITY AND
	CONVERGENCE
	MAGNET ASS'Y
RUBBER		RUBBER WEDGE
WEDGES	30	30
	30	30

31 mm		DEFLECTION	ADHESIVE
(1-3/16")	30	YOKE

GRASS			RUBBER
CLOTH	RUBBER WEDGES
			WEDGES
TAPE	LOCATION
			KIT

Fig. 3-1 Tube Assembly

2 POLE PURITY

ADJUST THE ANGLE

(VERTICAL LINES)

FIXED

YOKE

CLAMP

SCREW

6 POLE CONVERGENCE

4 POLE CONVERGENCE

ROTATE TWO TABS AT THE SAME TIME (HORIZONTAL LINES)

Fig. 3-2 Purity and Convergence Magnets

3-8	Samsung Electronics

Alignment and Adjustments

3-3-8 Center Convergence Adjustment

Note: Before attempting any convergence adjustment, make sure that the receiver has been powered ON for at least twenty minutes.

1.Input a crosshatch pattern from a color bar generator.

2.Adjust the Brightness and Contrast controls for a well defined pattern.

3.Adjust the two tabs of the 5-pole magnets. Change the angle between the tabs, and superimpose red and blue vertical lines in the center area of the picture screen.

4.Next, turn both tabs at the same time. Keep the angle between the tabs constant, and superimpose the red and blue horizontal lines at the center of the screen.

5.Adjust the two tabs of the 6-pole magnets. Superimpose the red/blue lines on the green. Adjusting the angle affects the horizontal lines.

6.Repeat adjustments 3, 4 and 5. The dot movement is complex because the 4-pole and 6- pole magnets interact.

BLUE	RED	RED/BLUE	GREEN
BLUE		RED/BLUE


RED		GREEN

4-Pole Magnet Movement		6-Pole Magnet Movement

Fig. 3-3 Center Convergence Adjustment

3-3-9 AGC Adjustment

1.Input a COLOR-BAR pattern. (CH2)

2.Set the RF input signal to 70 dBμV.

3.Use Generator for PM5518 & PM5418.

4.Set AGC (in the Factory Mode) so that the DC level of IC TDA8375 Pin 53 is 3.0 +0.05V.

3-3-10 AFT (VCO Adjustment)

1.Input an AGC adjustment signal.

2.Select Factory Mode VCO and press the MUTE key one time.

3.GEOMATRIX adjustments

VS	EWA
VA	EWP
VSL	EWC
HS	EWT

Samsung Electronics

3-9

Alignment and Adjustments

3-3-11 White Balance Adjustment

3-3-11 (A) SCREEN ADJUSTMENTS

1.Input a TOSHIBA pattern.

2.Check R506 “G” pin on the CRT PCB with an oscilloscope.

3.Enter the Horizontal Line Mode.

4.Adjust the Screen Control on the FBT so that the waveform of the 21st line is DC 2.0 (+0.5)V.

SIZE	29”	26”	22”

DC	2.0	2.4	2.4

3-3-11 (B) HIGH-LIGHT ADJUSTMENT

1.NOTE : If a color analyzer is not available, then approximate the following color adjustments “by eye”.

2.Input a TOSHIBA pattern.

3.Set high-light to 290/300 (X,Y) with a color analyzer.

4.Set low-light to 1.0F/L ( 22” low-light 1.2F/L).

5.Adjust RG, BG and set GG to step 32.

	29”	26”	22”

HEIGHT	37 + 3	45 + 3	45 + 3
LIGHT	37 + 3	45 + 3	45 + 3
LIGHT

3-3-11 (C) SUB-CONTRAST ADJUSTMENT

1.Set SCT so that the brightness level in highlight is 37 F/L (for a 29” SCREEN).

3-3-11 (D) SUB-BRIGHTNESS ADJUSTMENT

1.Input a TOSHIBA pattern.

2.Set SBT so that the brightness level in lowlight is 1.0 F/L.

High-Light

Low-Light

3-3-11 (E) SUB-COLOR ADJUSTMENT

Set “SCR” in the Service Mode to step 0.

3-3-11 (F) SUB-TINT ADJUSTMENT

Set “STT” in the Service Mode to step 10.

3-3-11 (G) VERTICAL SIZE ADJUSTMENT

1.Input a lion head pattern.

2.Set VS to 32 in the Factory Mode.

3.Set VA so that the top margin is 4.0. Adjust SL so that the bottom margin is 4.0. If the top and bottom margins are different, adjust VA so that their sum is 8.0.

3-3-11 (H) HORIZONTAL SHIFT ADJUSTMENT

1.Input a lion head pattern.

2.Adjust “HS” in the Service Mode so that the left and right margins of the lion head pattern are 5.0 + 0.5 : CT633BW/CT683BW, 6.3 + 0.5 : CT566BV/CT566BW/CT567BW/ CT568BW/CT766DW

3-10	Samsung Electronics

Troubleshooting

4. Troubleshooting

4-1 No Raster and No Sound

No Raster and No Sound

	No Voltage	Measure the B+
	No Voltage	Abnormal
		Voltage at the Cathode
		of D812 (D811)
		Normal
		Check +12.5 Line
Check/Replace	Normal	More than 130V	Check the horiz
Check/Replace	Normal	More than 130V	output signal at TR
			output signal at TR

IC801 Q801	collector.

Check/Replace AVR

Normal

Measure the B+

Circuit, Horiz Output

voltage at the cathode

Circuit and B+

of D812*

Voltage Line.

Open

Check/Replace F801

More than 130V

Less than 50V

Normal

Check/Replace FS

Check/Replace

AVR circuit

circuit

the AVR circuit.

(ADJ Pin of STR)

Check/Replace

1) D801

the power switch

2)Short the Degaussing Coil

3)C801

Samsung Electronics

4-1

+ 44 hidden pages