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SERVICE MANUAL




Color Television Receiver




Model: KS21TK305A




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SERVICE MANUAL

CONTENTS


I. IMPORTANT SERVICE SAFETY INFORMATION... ......3
II. ALIGNMENT PROCEDURES PLEASE READ BEFORE ATTEMPTING
SERVICE... 5
III. TV SPECIFICATION............... ............... ...... .........5
IV. TV ADJUSTMENT 7
V. IC INFORMATION..................... ........................... ... ....12
1. PHILIPS UOCIII CHIP (N603) 12
2. SWITCH POWER IC (N901) 41
3. VERTICAL DEFLECTION BOOSTER (N401) 45
4. AUDIO POWER AMPLIFIER (N202) 49
5. EEPROM 24C16 (N602) 52
VI. TV BLOCK DIAGRAM 57
Appendix 1: Schematic Circuit Diagram 58
Appendix 2: PCB Layout Diagram 59
Appendix 3: Exploded Views 63




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SERVICE MANUAL

IMPORTANT SERVICE SAFETY INFORMATION
Operating the receiver outside of its cabinet or with its back removed involves a shock hazard.
Work on these models should only be performed by those who are thoroughly familiar with
precautions necessary when working on high voltage equipment.
Exercise care when servicing this chassis with power applied. Many B plus and high voltage
RF terminals are exposed which, if carelessly contacted, can cause serious shock or result in damage
to the chassis. Maintain interconnecting ground lead connections between chassis, escutcheon,
picture tube dag and tuner when operating chassis.
These receivers have a "polarized" AC line cord. The AC plug is designed to fit into standard
AC outlets in one direction only. The wide blade connects to the "ground side" and the narrow blade
connects to the hot "side" of the AC line. This assures that the TV receiver is properly grounded to
the house wiring. If an extension cord must be used, make sure it is of the "polarized" type.
Since the chassis of this receive is connected to one side of the AC supply during operation,
service should not be attempted by anyone not familiar with the precautions necessary when
working on these types of equipment.
When it is necessary to make measurements or tests with AC power applied to the receiver
chassis, an Isolation Transformer must be used as a safety precaution and to prevent possible
damage to transistors. The Isolation Transformer should be connected between the TV line cord
plug and the AC power outlet.
Certain High voltage (HV) maybe cause X-ray radiation. Receivers should not be operated with
HV levels exceeding the specified rating for their chassis type. Higher voltage may also increase the
possibility of failure in the HV supply.
It is important to maintain specified values of all components in the horizontal and high voltage
circuits and anywhere else in the receive that could cause a rise in high voltage, or operating supply
voltages. No changes should be made the original design of the receiver.
Components shown in the shaded areas on the schematic diagram and/or identified by in the
replacement parts list should be replaced only with exact factory recommended replacement parts.
The use of unauthorized substitute parts man creats may create shock, fire, X-ray radiation, or other
hazards.
To determine the presence of high voltage, use an accurate high impedance HV meter
connected between the second anode lead and he CRT dag grounding device. When servicing the


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SERVICE MANUAL

High Voltage System remove static charges from it by connecting a 10K Ohm resistor in series Wan
insulated wire(such as test probe) between the picture tube dag and 2nd anode lead(Have AC line
cord disconnected from AC supply).
The picture tube use in this receiver employ integral implosion protection. Replace with a tube
of the same type number for continued safety. Do not lift picture tube by the neck. Handle the
picture tube only when wearing shatterproof goggles and after discharging the high voltage
completely, Keep others without shatter proof goggles away.
Before returning the receiver to the user, perform the following safety checks:
1. Inspect all lead dress to make certain that leads are not pinched or that hardware is not
lodged between the chassis and other metal parts in the receiver.
2. Replace all protective devices such as non-metallic control knobs, insulating fish-papers,
cabinet backs, adjustment and compartment covers of shields, isolation resistor-capacitor networks,
mechanical insulators etc.
3. To be sure that not shock hazard exists, a check for the presence of leakage current should be
made at each exposed metal part having a return path to the chassis (antenna, cabinet metal, screw
heads knobs and/or shafts, escutcheon, etc.) in the following manner.
Plug the AC line cord directly into a 110V/240V (or 180V/240V), AC receptacle. (Do not use
an Isolation Transformer during these checks.) All checks must be repeated with the AC line cord
plug connection reversed. (If necessary, a non-polarized adapter plug must be used only for the
purpose of completing these checks.)
If available, measure the current using an accurate leakage current tester. Any reading of
0.35mA or more is excessive and indicates a potential shock hazard which must be corrected before
returning the receiver to owner.
If a reliable leakage current tester is not available, this alternate method of measurement should
be used. Using two clip leads, connect a 1500 Ohm, 10 watt resistor paralleled by a 0.15MF
capacitor in series with a known earth ground, such as a water pipe or conduit and the metal part to
be checked. Use a VTVM or VOM with 1000 Ohms per Volt, or higher, sensitivity to measure this
AC voltage drop across the resistor,. Any reading of 0.35 volt RMS of more is excessive and
indicates potential shock hazard which must be corrected before returning he receiver to the owner.




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SERVICE MANUAL

ALIGNMENT PROCEDURES
PLEASE READ BEFORE ATTEMPTING SERVICE

1. Use an Isolation Transformer when performing any service on this chassis.
2. Never disconnect any leads while receiver is in operation.
3. Disconnect all power before attempting an repairs.
4. Do not short any position of the circuit while the power is on.
5. For safety reasons, replacing any components should be according with identical replacement
parts.
6. Before testing, warm up the TV for at least 30 minutes and demagnetize the CRT with an external
degaussing coil.
7. When removing a PCB or related component, after unfastening or changing a wire, be sure to put
the wire back in its original position.
8. Inferior silicon grease can damage IC's and transistors. When replacing IC's and transistors, use
only specified silicon grease,. Remove all old silicon when applying new silicon.
9. Before removing the anode cap, discharge drastically because it contains high voltage.



TV SPECIFICATION
1. Ambient Conditions:
1.1 Ambient Temperatures:
a. Operating: -10 ~ +40
b. Storage: -15 ~ +45
1.2 Humidity
a. Operation: <80%
b. Storage: <90%
1.3 Air Pressure: 86kpa ~ 106kpa


2. General Specification
2.1 Main IC: PHILIPS UOCIII CHIP (TDA12060 or TDA12062)
2.2 TV Broadcasting System:



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SERVICE MANUAL

PAL DK/BG/I
SECAM DK/BG
2.3 Scanning Lines & Frequencies
525 lines/60Hz or 625 lines/50Hz
15.75KHz/15.625KHz
2.4 Color Sub-Carrier: 4.433MHz/3.579MHz
2.5 IF: Picture 38.9MHz Sound 5.5/6.5MHz
2.6 Power Consumption: 75W;
2.7 Power Supply: AC 110-240V 50Hz