Daewoo DVQ-13H1FCN Service Manual

Contents

2SAFETY INSTRUCTIONCAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY.NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFAC-TURER°ØS APPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLYVOID THE WARRANTY, BUT MAY LEAD TO YOUR BEING LIABLE FOR ANTRESULTING PROPERTY DAMAGE OR USER INJURY.SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE THOR-OUGHLY FAMILIAR WITH ALL OF THE FOLLOWING SAFETY CHECKS ANDSERVICING GUIDELINES. TO DO OTHERWISE, INCREASES THE RISK OFPOTENTIAL HAZARDS AND INJURY TO THE USER.WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR PROTECTIONFROM A.C. LINE SHOCK.SAFETY CHECKSAFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRECTED, A CHECKSHOULD BE MADE OF THE FOLLOWING:SUBJECT:FIRE & SHOCK HAZARD1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN SUCH A WAY ASTO AVOID POSSIBILITY OF ADJACENT COMPONENT SHORTS. THIS ISESPECIALLY IMPORTANT ON THOSE MODULES WHICH ARE TRANS-PORTED TO AND FROM THE REPAIR SHOP.2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE DEVICES SUCH ASINSULATORS, BARRIERS, COVERS, SHIELDS, STRAIN RELIEFS, POWERSUPPLY CORDS, AND OTHER HARDWARE HAVE BEEN REINSTALLED PERORIGINAL DESIGN. BE SURE, THAT THE SAFETY PURPOSE OF THEPOLARIZED LINE PLUG HAS NOT BEEN DEFEATED.3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE COLD SOL-DER JOINTS, SOLDER SPLASHES OF SHARP SOLDER POINTS. BE CER-TAIN TO REMOVE ALL LOOSE FOREIGN PARTICLES.4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR DETERIORATION TOPARTS AND COMPONENTS, FOR FRAYED LEADS, DAMAGED INSULATION(INCLUDING A.C. CORD), AND REPLACE IF NECESSARY. FOLLOW ORIGI-NAL LAYOUT, LEAD LENGTH AND DRESS.5. NO LEAD OR COMPONENT SHOULD TOUCH A RECEIVING TUBE OR ARESISTOR RATED AT 1 WATT OR MORE. LEAD TENSION AROUND PRO-TRUDING METAL 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 REPLACEMENT COMPONENTS OTHER THAN THOSE SPECI-FIED OR MAKE UNRECOMMENDED CIRCUIT MODIFICATIONS.7. AFTER RE-ASSEMBLY OF THE STE ALWAYS PERFORM AN A.C. LEAKAGETEST ON ALL EXPOSED METALLIC PARTS OF THE CABINET. (THE CHAN-NEL SELECTOR KNOB, ANTENNA TERMINALS, HANDLE AND SCREWS) TOBE SURE THE SET IS SAFE TO OPERATE WITHOUT DANGER OF ELECTRI-CAL SHOCK. DO NOT USE A LINE ISOLATION TRANSFORMER DURINGTHIS TEST USE AN A.C. VOLTMETER, HAVING 5000 OHMS PER VOLT ORMORE SENSITIVITY, IN THE FOLLOWING MANNER : CONNECT A 1500 OHM10 WATT RESISTOR, PARALLELED BY A .15 MFD. 150V A.C. TYPE CAPACI-TOR BETWEEN A KNOWN GOOD EARTH GROUND (WATER POPE, CON-DUIT, ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME.MEASURE THE A.C. VOLTAGE ACROSS THE COMBINATION OF 1500 OHMRESISTOR AND .15 MFD CAPACITOR. REVERSE THE A.C. PLUG ANDREPEAT A.C. VOLTAGE MEASUREMENTS FOR EACH EXPOSED METALLICPART. VOLTAGE MEASURED MUST NOT EXCEED .75 VOLTS R.M.S THISCORRESPONDS TO 0.5 MILLIAMP A.C. NAY VALUE EXCEEDING THIS LIMITCONSTITUTES A POTENTIAL SHOCK HAZARD AND MUST BE CORRECTEDIMMEDIATELY.SUBJECT : GRAPHIC SYMBOLSTHE LIGHTNING FLASH WITH ARROWHEAD SYMBOL,WITHIN AN EQUILATERAL TRIANGLE, IS INTENDEDTO ALERT THE SERVICE PERSONNEL TO THE PRES-ENCE OF UNINSULATED “DANGEROUS VOLTAGE”THAT MAY BE OF SUFFICIENT MAGNITUDE TO CON-STITUTE A RISK OF ELECTRIC SHOCK.THE EXCLAMATION POINT WITHIN AN EQUILATERALTRIANGLE IS INTENDED TO ALERT THE SERVICEPERSONNEL TO THE PRESENCE OF IMPORTANTSAFETY INFORMATION ON SERVICE LITERATURE.SUBJECT : X-RADIATION1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PERSON-NEL COVER THE SUBJECT OF X-RADIATION. THE ONLY POTENTIALSOURCE OF X-RAYS IN CURRENT T.V. RECEIVERS IS THE PICTURE TUBE.HOWEVER, THIS TUBE DOES NOT EMIT X-RAYS WHEN THE HIGH VOLT-AGE IS AT THE FACTORY SPECIFIED LEVEL. THE PROPER VALUE ISGIVEN IN THE APPLICABLE SCHEMATIC. OPERATION AT HIGHER VOLT-AGES MAY CAUSE A FAILURE OF THE PICTURE TUBE OR HIGH VOLTAGESUPPLY AND, UNDER CERTAIN CIRCUMSTANCES, AMY PRODUCE RADIA-TION IN EXCESS OF DESIRABLE LEVELS.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-INSTALL THEM.3. IT IS ESSENTIAL THAT SERVICE PERSONNEL HAVE AVAILABLE AN ACCU-RATE AND RELIABLE HIGH VOLTAGE METER. THE CALIBRATION OF THEMETER SHOULD BE CHECKED PERIODICALLY AGAINST A REFERENCESTANDARD. SUCH AS THE ONE AVAILABLE AT YOUR DISTRIBUTOR.4. WHEN THE HIGH VOLTAGE CIRCUITRY IS OPERATING PROPERLY THEREIS NO POSSIBILITY OF AN X-RADIATION PROBLEM. EVERY TIME A COLORCHASSIS IS SERVICED, THE BRIGHTNESS SHOULD BE RUN UP ANDDOWN WHILE MONITORING THE HIGH VOLTAGE WITH A METER TO BECERTAIN THAT THE HIGH VOLTAGE DOES NOT EXCEED THE SPECIFIEDVALUE AND THAT IT IS REGULATING CORRECTLY. WE SUGGEST THATYOU AND YOUR SERVICE ORGANIZATION REVIEW TEST PROCEDURESSO THAT VOLTAGE REGULATION IS ALWAYS CHECKED AS A STANDARDSERVICING PROCEDURE, AND THAT THE HIGH VOLTAGE READING BERECORDED ON EACH CUSTOMER°ØS INVOICE.5. WHEN TROUBLESHOOTING AND MAKING TEST MEASUREMENTS IN APRODUCT WITH A PROBLEM OF EXCESSIVE HIGH VOLTAGE, AVOIDBEING UNNECESSARILY CLOSE TO THE PICTURE TUBE AND THE HIGHVOLTAGE SUPPLY. DO NOT OPERATE THE PRODUCT LONGER THAN ISNECESSARY TO LOCATE THE CAUSE OF EXCESSIVE VOLTAGE.6. REFER TO HV, B+ AND SHUTDOWN ADJUSTMENT PROCEDURESDESCRIBED IN THE APPROPRIATE SCHEMATIC AND DIAGRAMS (WHEREUSED).SUBJECT : IMPLOSION1. ALL DIRECT VIEWED PICTURE TUBES ARE EQUIPPED WITH AN INTEGRAIMPLOSION PROTECTION SYSTEM. BUT CARE SHOULD BE TAKEN TOAVOID DAMAGE DURING INSTALLATION. AVOID SCRATCHING THETUBE. OF SCRATCHED REPLACE IT.2. USE ONLY RECOMMENDED FACTORY REPLACEMENT TUBES.SUBJECT : TIPS ON PROPER INSTALLATION1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS, CUBBYHOLE ORCLOSELY FITTING SHELF SPACE, OVER OR CLOSE TO HEAT DUCT, OR INTHE PATH OF HEATED AIR FLOW.2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIOINSTALLATIONS WHERE DEW IS A FACTOR, NEAR STEAM RADIATORSWHERE STEAM LEAKAGE IS A FACTOR, ETC.3. AVOID PLACEMENT WHERE DRAPERIES MAY OBSTRUCT REAR VENTING.THE CUSTOMER SHOULD ALSO AVOID THE USE OF DECORATIVESCARVES OR OTHER COVERINGS WHICH MIGHT OBSTRUCT VENTILA-TION.4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMERCIALMOUNTING KIT, MUST FOLLOW THE FACTORY APPROVED MOUNTINGINSTRUCTIONS. A PRODUCT MOUNTED TO A SHELF OR PLATFORM MUSTRETAIN ITS ORIGINAL FEET (OR THE EQUIVALENT THICKNESS IN SPAC-ERS)TO PROVIDE ADEQUATE AIR FLOW ACROSS THE BOTTOM, BOLTSOR SCREWS USED FOR FASTENERS MUST NOT TOUCH ANY PARTS ORWIRING. PERFORM LEAKAGE TEST ON CUSTOMIZED INSTALLATIONS.5. CAUTION CUSTOMERS AGAINST THE MOUNTING OF A PRODUCT ONSLOPING SHELF OR A TILTED POSITION, UNLESS THE PRODUCT ISPROPERLY SECURED.6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE ON ITS MOUNT-ING TO THE CART. CAUTION THE CUSTOMER ON THE HAZARDS OF TRY-ING TO ROLL A CART WITH SMALL CASTERS ACROSS THRESHOLDS ORDEEP PILE CARPETS.7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR STAND WHICHHAS NOT BEEN LISTED BY UNDERWRITERS LABORATORIES. INC. FORUSE WITH THEIR SPECIFIC MODEL OF TELEVISION RECEIVER ORGENERICALLY APPROVED FOR USE WITH T.V.S OF THE SAME ORLARGER SCREEN SIZE.8. CAUTION CUSTOMERS AGAINST THE USE OF EXTENSION CORDS,EXPLAIN THAT A FOREST OF EXTENSIONS SPROUTING FROM A SINGLEOUTLET CAN LEAD TO DISASTROUS CONSEQUENCES TO HOME ANDFAMILY.10WATTGOOD EARTH GROUNDSUCH AS THE WATERPIPE, CONDUIT, ETC.1500 OHMA.C. VOLTMETERPLACE THIS PROBEON EACH EXPOSEDMETAL PART0.15 uF