SAMSUNG CS29A6MTRXBWT Service Manual

COLOR TELEVISION RECEIVER

Chassis: SCT55A

Model: CS29A6MTRX/BWT

COLOR TELEVISION RECEIVER			CONTENTS
1.			Precautions
2.			Reference Information
3.			Specifications
4.			Disassembly and Reassembly
5.			Alignment and Adjustment s
6.			Troubleshooting
7.			Exploded View and Parts List
8.			Electric Parts List
9.			Block Diagrams
10.			PCB Layout
11.			Wiring Diagram
12.			Schematic Diagrams

ELECTRONICS

©Samsung Electronics Co., Ltd. JUN. 1999 Printed in Korea

3SCT55A-2901

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.

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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.

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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

Reference Information

2. Reference Information

2-1 Tables of Abbreviations and Acronyms

Table 2-1 Abbreviations

A	Ampere	MV	Megavolt
Ah	Ampere-hour	MW	Megawatt
Å	Angstrom	MΩ	Megohm
dB	Decibel	m	Meter
dBm	Decibel Referenced to One	µA	Microampere
	Milliwatt	µF	Microfarad
°C	Degree Celsius	µH	Microhenry
°F	Degree Fahrenheit	µm	Micrometer
°K	degree Kelvin	µs	Microsecond
F	Farad	µW	Microwatt
G	Gauss	mA	Milliampere
GHz	Gigahertz	mg	Milligram
g	Gram	mH	Millihenry
H	Henry	mI	Milliliter
Hz	Hertz	mm	Millimeter
h	Hour	ms	Millisecond
ips	Inches Per Second	mV	Millivolt
kWh	Kilowatt-hour	nF	Nanofarad
kg	Kilogram	Ω	Ohm
kHz	Kilohertz	pF	Picofarad
kΩ	Kilohm	Ib	Pound
km	Kilometer	rpm	Revolutions Per Minute
km/h	Kilometer Per Hour	rps	Revolutions Per Second
kV	Kilovolt	s	Second (Time)
kVA	Kilovolt-ampere	V	Volt
kW	Kilowatt	VA	Volt-ampere
I	Liter	W	Watt
MHz	Megahertz	Wh	Watt-hour

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Reference Information

Table 2-1 Abbreviations

ABL	Automatic Brightness Limiter	I/O	Input/output
AC	Alternating Current	L	Left
ACC	Automatic Chroma Control	L	Low
AF	Audio Frequency	LED	Light Emitting Diode
AFC	Automatic Frequency Control	LF	Low Frequency
AFT	Automatic Fine Tuning	MOSFET	Metal-Oxide-Semiconductor-Field-Effect-Tr
AGC	Automatic Gain Control	MTS	Multi-channel Television Sound
AM	Amplitude Modulation	NAB	National Association of Broadcasters
ANSI	American National Standards Institute	NEC	National Electric Code
APC	Automatic Phase Control	NTSC	National Television Systems Committee
APC	Automatic Picture Control	OSD	On Screen Display
A/V	Audio-Video	PCB	Printed Circuit Board
AVC	Automatic Volume Control	PLL	Phase-Locked Loop
BAL	Balance	PWM	Pulse Width Modulation
BPF	Bandpass Filter	QIF	Quadrature Intermediate Frequency
B-Y	Blue-Y	R	Right
CATV	Community Antenna Television (Cable TV)	RC	Resistor & Capacitor
CB	Citizens Band	RF	Radio Frequency
CCD	Charge Coupled Device	R-Y	Red-Y
CCTV	Closed Circuit Television	SAP	Second Audio Program
Ch	Channel	SAW	Surface Acoustic Wave(Filter)
CRT	Cathode Ray Tube	SIF	Sound Intermediate Frequency
CW	Continuous Wave	SMPS	Switching Mode Power Supply
DC	Direct Current	S/N	Signal/Noise
DVM	Digital Volt Meter	SW	Switch
EIA	Electronics Industries Association	TP	Test Point
ESD	Electrostatic Discharge	TTL	Transistor Transistor Logic
ESD	Electrostatically Sensitive Device	TV	Television
FBP	Feedback Pulse	UHF	Ultra High Frequency
FBT	Flyback Transformer	UL	Underwriters Laboratories
FF	Flip-Flop	UV	Ultraviolet
FM	Frequency Modulation	VCD	Variable-Capacitance Diode
FS	Fail Safe	VCO	Voltage Controlled Oscillator
GND	Ground	VCXO	Voltage Controlled Crystal Oscillator
G-Y	Green-Y	VHF	Very High Frequency
H	High	VIF	Video Intermediate Frequency
HF	High-Frequency	VR	Variable Resistor
HI-FI	High Fidelity	VTR	Video Tape Recorder
IC	Inductance-Capacitance	VTVM	Vacuum Tube Voltmeter
IC	Integrated Circuit	TR	Transistor
IF	Intermediate Frequency

2-2	Samsung Electronics

Reference Information

2-1 Tables of Abbreviations and Acronyms

100 Series ....................................................................................................................................................	IF processing
200 Series ..............................................................................................................................	Video, Chroma Processing
300 Series ...........................................................................................................................................	Vertical Deflection
400 Series ......................................................................................................................................	Horizontal deflection
500 Series .....................................................................................................................................	CRT Drive Processing
600 Series ............................................................................................................................................	Sound Processing
700 Series .............................................................................................................................	A/V Switching Processing
800 Series .................................................................................................................................	AC Input Power Supply
900 Series ...............................................................................................................................................	MICOM Section
RT, CT, ICT .......................................................................................................................................	TELETEXT Section
RC, CC, HC, SWY .............................................................................................................	SNAP-IN Section (Control)
RV,CV,LV,QV ...............................................................................................................................................	V/M Section
RJ,CJ,LJ,DJ,ICJ .......................................................................................................................................	NICAM Section
RP,CP,LP,XP,ICP ............................................................................................................................................	PIP Section
RC,CC,DZC,QC ...........................................................................................................................	COMB Filter Section
RP,PD ..........................................................................................................................................	POWER-S/W Section

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Reference Information

2-2 IC Line Up

Table 2 - 1 IC Line - Up

Loc No.

No.

Specification

Description

Remarks

IC201

TDA8375

ONE CHIP TV PROCESSOR

N3 VERSION

IC203

TDA9177

LINE TRANSIENT IMPROVEMENT IC (LTI BOOSTER)

IC205

TEA5114A

R/G/B SWITCHING IC

SCART OPTION

IC206

TEA5114A

R/G/B SWITCHING IC

TTX/OSD

IC207

TEA5114A

R/G/B SWITCHING IC

PIP/TTX

IC208

TDA9170

YUV PICTURE IMPROVEMENT PROCESSOR

IC301

LA7845

VERTICAL AMP

POWER

IC401

MC4558C

OP AMPLIFIER (EW AMPLIFIER)

POWER

IC501

TDA6101Q

VIDEO OUTPUT AMPLIFIER

CRT

IC502

TDA6101Q

VIDEO OUTPUT AMPLIFIER

CRT

IC503

TDA6101Q

VIDEO OUTPUT AMPLIFIER

CRT

IC504

MC4558C

OP AMPLIFIER (TILT AMPLIFIER)

CRT

IC505

SPK101T

SPOT KILLER HYBRID IC

CRT

IC6001

TDA9875/9870

DIGITAL TV SOUND PROCESSOR

AUDIO MODULE

IC6002

TDA9808

VIF/SIF PROCESSOR (SIF PROCESSOR)

AUDIO MODULE

IC6003

TDA7050

2-CHANNEL HEADPHONE AMPLIFIER

AUDIO MODULE

IC6004

MC4558C

OP AMPLIFIER (AUDIO AMPLIFIER)

AUDIO MODULE

IC601

TDA7297

SOUND AMP

IC701

CXA1855S

AUDIO/VIDEO SWITCHING IC

IC801

STR-S6709

SMPS CONTROL IC

POWER

IC802

LTV817B

PHOTO COUPLER

POWER

IC901

Z89313(Z90341)

MICRO PROCESSOR

IC902

KIA7042P

RESET IC

IC903

PQ09RF1

9V SWITCHABLE REGULATOR

IC904

KA7808

8V REGULATOR

2-4	Samsung Electronics

Reference Information

Table 2 - 1 IC Line - Up (Continued)

Loc No.

No.

Specification

Description

Remarks

IC905

KA7812A

12V REGULATOR

IC906

KA7805A

5V REGULATOR

IC907

KA7808

8V REGULATOR

IC908

24C08

E2PROM

IC909

KA7805A

5V REGULATOR

IC910

KA7805A

5V REGULATOR

ICP03

TDA9160A

PAL/NTSC/SECAM DECODER AND SYNC PROCESSOR

PIP MODULE

ICP05

SAB9077H

PIP CONTROLLER

PIP MODULE

ICP06

548262

MEMORY-2M

PIP MODULE

IC101

PAP102

IF PRE-AMP HYBRID IC

IC202

TDA4665

BASE BAND DELAY LINE

SECAM MODULE

IC203

TDA8395P

SECAM DECODER

SECAM MODULE

ICT01

SAA528IP/E

TELETEXT

ICP02

TDA9808

VIF/SIF-DETECTOR

PIP MODULE

ICP01

PAP101

IF PRE-AMP HYBRID IC

PIP MODULE

ICP04

TDA3504

RGB-MATRIX

PIP MODULE

ICP07

KIA7042P

RESET IC

PIP MODULE

ICP08

TDA4665T

BASE BAND DELAY LINE

PIP MODULE

Option : OSD Language

Table 2-2


Loc No.	Specification	Description	Remarks

		ENG/ARAB/FRENCH/CHINESE/	2-TUNER
IC901	SZM-162M	MALAYSIA/INDONESIA/VIETNAM/	MULTI-PIP
IC901	SZM-162M
		THAI/RUSSIAN/CROATIA/BULGARIA/	MULTI-LANGUAGE
		POLAND/ROMANIA/CZECH/TURKEY/HUNGARY

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Specifications

3. Specifications


	Model	761A/3001A

	TUNING	Frequency Synthesizer

SYSTEM	COLOUR	PAL, SECAM, NTSC3.58, NTSC4.43

	SOUND	B/G, D/K, I,M

	NICAM	B/G,I

ANTENNA IMPEDANCE		75 ohm unbalanced coaxial

SCREEN SIZE		70.8 cm

POWER	REQUIREMENTS	Main voltage : 220V/230V/240V~

		Range : 100 - 260V~

	FREQUENCY	50/60Hz

PROGRAMME CHANNEL		100 channels

Specifications are subject to change.

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3-1

Disassembly and Reassembly

4. Disassembly and Reassembly

4-1 Cabinet

1.Remove 9 screws located on the side of the cabinet.

2.Pull the Main Assembly backwards to remove.

3.To reassemble, place the receiver on a flat surface and repeat the sequence in reverse order.

4.To check that that the Chassis Assembly is installed correctly, attempt to pull if from the front cabinet.

Fig. 4-1

Samsung Electronics

4-1

Disassembly and Reassembly

4-2 Speaker

1.Separate Connectors (a), (b).

2.Separate wires from twist-lock.

3.Remove 2 screws, (c).

4.To reassemble, repeat the sequence in reverse order.

Fig. 4-2

4-2	Samsung Electronics

Disassembly and Reassembly

4-3 Chassis Assembly

4-3-1 Removal from Front Cabinet

1. Lift and pull back the chassis mounting.

Fig. 4-3

Fig. 4-4

Samsung Electronics

4-3

Disassembly and Reassembly

4-3-2 Terminal Board

Removal

1.Pull the power cord to the left and remove it.

2.Remove 1 screw ( a).

3.lift up the 2 brackets( b). Separate the terminal board from the chassis mount.

4.To reassemble, refer to Fig. 4-6.

TERMINAL-BOARD

HOLDER-CHASSIS

WIRELESS H/P-JACK

S-VHS JACK

BRACKET b

Fig. 4-5

Insert

"Insert on the left and right bottom of the terminal board, into

"hole on the holder chassis.

Fig. 4-6

4-4	Samsung Electronics

Disassembly and Reassembly

4-3-3 PCB

Removal

1.Refer to the Fig. 4-4.

2.Remove the wire (1P) from the chassis mounting.

3.Pull the PCB guides backwards.

4.Lift both edges of the PCB and pull out.

Disassembly

1.Ensure that the PCB is well positioned in the PCB guides.

2.The power cord must not touch the heat-sink, D73.

3.The PCB guide is part of the chassis mounting ; if a new PCB guide is needed, the complete chassis mounting must be replaced.

4-3-4 SNAPIN Removal

SNAPIN-CONTROL

Fig. 4-7 Press the SNAPIN (b) with thumb ; pull the left holder-bracket (a) with index finger

Samsung Electronics

4-5

Disassembly and Reassembly

4-3-5 Chassis Reassembly

1.Close the SNAPIN door.

2.Place the chassis bracket (b) onto (a) on the bottom of the cabinet.

3.Push the bracket into the hole (a) until a “click” is heard.

4.Check that the SNAPIN door opens and closes.

F/CABINET

HOLDER-CHASSIS

Fig. 4-8

4-6	Samsung Electronics

Alignment and Adjustments

5. Alignment and Adjustments

5-1 General Alignment Instructions

1.Usually, a color TV-VCR 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, demagnetize, perform 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.

5-2 Automatic Degaussing

A degaussing coil is mounted around the picture tube, so that external degaussing after moving the TV should be unnecessary. But 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 is moved or turned in a different direction, the power should be OFF 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 turning power OFF.

If color shading persists, perform the following Color Purity and Convergence adjustments.

5-3 High Voltage Check

CAUTION: There is no high voltage adjustment on this chassis. The B+ power supply should be +130 volts (with full colorbar 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.Adjust the Brightness and contrast controls to

both extremes. Ensure that the high voltage does not exceed 32 KV under any conditions.

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