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Service Manual
Color Television
CHASSIS : CN-201A/B
NTSC-M SYSTEM
MODEL: DTQ-14Q1FS, DTQ-14Q2TS
DTQ-14Q3FS, DTQ-14T1AS
DTQ-14T2FS, DTQ-20Q1FS
DTQ-20Q2FS, DTQ-20Q3FS
DTQ-20T1AS, DTQ-20T2AS
DTQ-20T1FS, DTQ-20T2FS
DTQ-20T3FS, DTQ-21T1FS
DTQ-21T2FS, DTQ-21T5FS
DTQ-21T9FS, DTQ-20T1FC

Caution
: In this Manual, some parts can be changed for improving, their
performance without notice in the parts list. So, if you need the
latest parts information,please refer to PPL(Parts Price List) in
Service Information Center (http://svc.dwe.co.kr).

DAEWOO ELECTRONICS CO., LTD.
FEATURES
FS (Frequency Synthesizer) Tuning System
CATV Ready
High Focus Minineck CRT

ELECTRICAL SPECIFICATIONS
POWER INPUT
AC90V - AC250V 50/60Hz
DTQ-20T1FC : 120V 60HZ ONLY
POWER RATING
14" Model 60W
20" MONO Model 70W
20" ST Model 80W
21" ST Model 80W
INTERMEDIATE FREQUENCIES
PICTURE IF CARRIER FREQUENCY 45.75MHz
SOUND IF CARRIER FREQUENCY 41.25MHz
COLOR SUB CARRIER FREQUENCY 42.17MHz
AUDIO OUTPUT RATING MONO(2W) ST(3W+3W)
SPEAKER 3W 16ohm
ANTENNA INPUT IMPEDANCE VHF/UHF 75 ohm UNBALANCED
TUNING RANGES
VHF 2 THRU 13
UHF 14 THRU 69
CATV 1 THRU 125

CONTENTS
Safety Precautions 3
Control View 6
Important Service Notes 8
Block Diagram 9
General Adjustments 10
Operation Charaeteristic of Power Block 14
Trouble Shooting Charts 22
Description of Semiconductors 28
Printed Circuit Board Diagram 32
Exploded Views 33
Schematic Diagram with Waveforms 50
Parts List 51
Option List 65

2
PRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO VIDEO PRODUCTS
950ART94
CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY. NEVER SUBJECT : X-RADIATION 1009
PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFACTURER S APPROVAL.
UNAUTHORIZED MODIFICATIONS WILL NOT ONLY VOID THE WARRANTY, BUT MAY 1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PERSONNEL COVER
LEAD TO YOUR BEING LIABLE FOR ANT RESULTING PROPERTY DAMAGE OR USER THE SUBJECT OF X-RADIATION. THE ONLY POTENTIAL SOURCE OF X-RAYS IN
INJURY. CURRENT T.V. RECEIVERS IS THE PICTURE TUBE. HOWEVER, THIS TUBE DOES NOT
EMIT X-RAYS WHEN THE HIGH VOLTAGE IS AT THE FACTORY SPECIFIED LEVEL. THE
SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE THOROUGHLY PROPER VALUE IS GIVEN IN THE APPLICABLE SCHEMATIC. OPERATION AT HIGHER
FAMILIAR WITH ALL OF THE FOLLOWING SAFETY CHECKS AND SERVICING VOLTAGES MAY CAUSE A FAILURE OF THE PICTURE TUBE OR HIGH VOLTAGE
GUIDELINES. TO DO OTHERWISE, INCREASES THE RISK OF POTENTIAL HAZARDS AND SUPPLY AND, UNDER CERTAIN CIRCUMSTANCES, AMY PRODUCE RADIATION IN
INJURY TO THE USER. EXCESS OF DESIRABLE LEVELS.
WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR PROTECTION FROM A.C.
LINE SHOCK. 2. ONLY FACTORY SPECIFIED C.R.T ANODE CONNECTORS MUST BE USED.
DEGAUSSING SHIELDS ALSO SERVE AS X-RAY SHIELD IN COLOR SETS. ALWAYS RE-
SAFETY CHECKS INSTALL THEM.
AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRECTED, A CHECK SHOULD
BE MADE OF THE FOLLOWING: 3. IT IS ESSENTIAL THAT SERVICE PERSONNEL HAVE AVAILABLE AN ACCURATE AND
RELIABLE HIGH VOLTAGE METER. THE CALIBRATION OF THE METER SHOULD BE
SUBJECT:FIRE & SHOCK HAZARD CHECKED PERIODICALLY AGAINST A REFERENCE STANDARD. SUCH AS THE ONE
AVAILABLE AT YOUR DISTRIBUTOR.
1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN SUCH A WAY AS TO AVOID
POSSIBILITY OF ADJACENT COMPONENT SHORTS. THIS IS ESPECIALLY IMPORTANT 4. WHEN THE HIGH VOLTAGE CIRCUITRY IS OPERATING PROPERLY THERE IS NO
ON THOSE MODULES WHICH ARE TRANSPORTED TO AND FROM THE REPAIR SHOP. POSSIBILITY OF AN X-RADIATION PROBLEM. EVERY TIME A COLOR CHASSIS IS
2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE DEVICES SUCH AS SERVICED, THE BRIGHTNESS SHOULD BE RUN UP AND DOWN WHILE MONITORING
INSULATORS, BARRIERS, COVERS, SHIELDS, STRAIN RELIEFS, POWER SUPPLY THE HIGH VOLTAGE WITH A METER TO BE CERTAIN THAT THE HIGH VOLTAGE DOES
CORDS, AND OTHER HARDWARE HAVE BEEN REINSTALLED PER ORIGINAL DESIGN. NOT EXCEED THE SPECIFIED VALUE AND THAT IT IS REGULATING CORRECTLY. WE
BE SURE, THAT THE SAFETY PURPOSE OF THE POLARIZED LINE PLUG HAS NOT SUGGEST THAT YOU AND YOUR SERVICE ORGANIZATION REVIEW TEST
BEEN DEFEATED. PROCEDURES SO THAT VOLTAGE REGULATION IS ALWAYS CHECKED AS A
STANDARD SERVICING PROCEDURE, AND THAT THE HIGH VOLTAGE READING BE
3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE COLD SOLDER JOINTS,
RECORDED ON EACH CUSTOMER S INVOICE.
SOLDER SPLASHES OF SHARP SOLDER POINTS. BE CERTAIN TO REMOVE ALL
LOOSE FOREIGN PARTICLES. 5. WHEN TROUBLESHOOTING AND MAKING TEST MEASUREMENTS IN A PRODUCT WITH
4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR DETERIORATION TO PARTS AND A PROBLEM OF EXCESSIVE HIGH VOLTAGE, AVOID BEING UNNECESSARILY CLOSE
COMPONENTS, FOR FRAYED LEADS, DAMAGED INSULATION (INCLUDING A.C. CORD), TO THE PICTURE TUBE AND THE HIGH VOLTAGE SUPPLY. DO NOT OPERATE THE
AND REPLACE IF NECESSARY. FOLLOW ORIGINAL LAYOUT, LEAD LENGTH AND PRODUCT LONGER THAN IS NECESSARY TO LOCATE THE CAUSE OF EXCESSIVE
DRESS. VOLTAGE.
5. NO LEAD OR COMPONENT SHOULD TOUCH A RECEIVING TUBE OR A RESISTOR 6. REFER TO HV, B + AND SHUTDOWN ADJUSTMENT PROCEDURES DESCRIBED IN THE
RATED AT 1 WATT OR MORE. LEAD TENSION AROUND PROTRUDING METAL APPROPRIATE SCHEMATIC AND DIAGRAMS (WHERE USED).
SURFACES MUST BE AVOIDED.
6. ALL CRITICAL COMPONENTS SUCH AS FUSES, FLAMEPROOF RESISTOR,
CAPACITORS, ETC. MUST BE REPLACED WITH EXACT FACTORY TYPES. DO NOT USE SUBJECT : IMPLOSION
REPLACEMENT COMPONENTS OTHER THAN THOSE SPECIFIED OR MAKE
UNRECOMMENDED CIRCUIT MODIFICATIONS. 1. ALL DIRECT VIEWED PICTURE TUBES ARE EQUIPPED WITH AN INTEGRAL IMPLOSION
7. AFTER RE-ASSEMBLY OF THE STE ALWAYS PERFORM AN A.C. LEAKAGE TEST ON PROTECTION SYSTEM. BUT CARE SHOULD BE TAKEN TO AVOID DAMAGE DURING
ALL EXPOSED METALLIC PARTS OF THE CABINET. (THE CHANNEL SELECTOR KNOB, INSTALLATION. AVOID SCRATCHING THE TUBE. OF SCRATCHED REPLACE IT.
ANTENNA TERMINALS, HANDLE AND SCREWS) TO BE SURE THE SET IS SAFE TO
2. USE ONLY RECOMMENDED FACTORY REPLACEMENT TUBES.
OPERATE WITHOUT DANGER OF ELECTRICAL SHOCK. DO NOT USE A LINE
ISOLATION TRANSFORMER DURING THIS TEST USE AN A.C. VOLTMETER,
HAVING 5000 OHMS PER VOLT OR MORE SENSITIVITY, IN THE FOLLOWING MANNER :
CONNECT A 1500 OHM 10 WATT RESISTOR, PARALLELED BY A .15 MFD. 150V A.C. SUBJECT : TIPS ON PROPER INSTALLATION
TYPE CAPACITOR BETWEEN A KNOWN GOOD EARTH GROUND (WATER POPE,
1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS, CUBBYHOLE OR CLOSELY
CONDUIT, ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME. MEASURE
FITTING SHELF SPACE, OVER OR CLOSE TO HEAT DUCT, OR IN THE PATH OF
THE A.C. VOLTAGE ACROSS THE COMBINATION OF 1500 OHM RESISTOR AND .15
HEATED AIR FLOW.
MFD CAPACITOR. REVERSE THE A.C. PLUG AND REPEAT A.C. VOLTAGE
MEASUREMENTS FOR EACH EXPOSED METALLIC PART. VOLTAGE MEASURED MUST 2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIO INSTALLATIONS
NOT EXCEED .75 VOLTS R.M.S THIS CORRESPONDS TO 0.5 MILLIAMP A.C. NAY VALUE WHERE DEW IS A FACTOR, NEAR STEAM RADIATORS WHERE STEAM LEAKAGE IS A
EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL SHOCK HAZARD AND MUST BE FACTOR, ETC.
CORRECTED IMMEDIATELY.
3. AVOID PLACEMENT WHERE DRAPERIES MAY OBSTRUCT REAR VENTING. THE
A.C. VOLTMETER
CUSTOMER SHOULD ALSO AVOID THE USE OF DECORATIVE SCARVES OR OTHER
A.C. VOLTMETER COVERINGS WHICH MIGHT OBSTRUCT VENTILATION.

4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMERCIAL MOUNTING KIT,
MUST FOLLOW THE FACTORY APPROVED MOUNTING INSTRUCTIONS. A PRODUCT
MOUNTED TO A SHELF OR PLATFORM MUST RETAIN ITS ORIGINAL FEET (OR THE
EQUIVALENT THICKNESS IN SPACERS)TO PROVIDE ADEQUATE AIR FLOW ACROSS
THE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERS MUST NOT TOUCH ANY
0.15