Daewoo DS-2000N, Service Manual

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CAUTION: DO NOT ATTEMPTTOMODIFYTHISPRODUCTINANYWAYAND
N E V E R P E R F O R M
C U S T O M I Z E D I N S T A L L A T I O N S W I T H O U T
MANUFACTURER'SAPPROVAL. UNAUTHORIZEDMODIFICATIONSWILL NOT
ONLY VOID THE WARRANTY, BUT MAY LEAD TO YOUR BEINGLIABLE FOR
ANYRESULTINGPROPERTYDAMAGEORUSERINJURY.
SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE
THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING SAFETY CHECKS
ANDSERVICINGGUIDELINES.TODOOTHERWISE,INCREASESTHERISKOF
POTENTIALHAZARDSANDINJURYTOTHEUSER.
WHILE SERVICING, USE AN ISOLATION TRANSFORMERFOR PROTECTION
FROMA.C.LINESHOCK.
AFTERTHEORIGINALSERVICEPROBLEMHASBEENCORRECTED,ACHECK
SHOULDBEMADEOFTHEFOLLOWING.
1. BE SURETHAT ALLCOMPONENTSAREPOSITIONEDINSUCHAWAYAS
TO AVOID POSSIBILITY OF ADJACENT COMPONENT SHORTS. THIS IS
ESPECIALLY IMPORTANT ON THOSE MODULES WITCH ARE
TRANSPORTEDTOANDFROMTHEREPAIRSHOP.
2. NEVERRELEASEAREPAIRUNLESSALLPROTECTIVEDEVICESSUCHAS
INSULATORS,BARRIERS, COVERS, SHIELDS, STRAINRELIEFS,POWER
SUPPLYCORDS,ANDOTHERHARDWAREHAVEBEENREINSTALLEDPER
ORIGINAL DESIGN. BE SURE THAT THE SAFETY PURPOSE OF THE
POLARIZEDLINEPLUGHASNOTBEENDEFEATED.
3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE COLD
SOLDER JOINTS, SOLDER SPLASHES OR SHARP SOLDER POINTS. BE
CERTAINTOREMOVEALLLOOSEFOREIGNPARTICLES.
4. CHECK FOR PHYSICAL EVIDENCE DF DAMAGE OR DETERIORATIONTO
PARTS AND COMPONENTS, FOR FRAYED LEADS AND DAMAGED
INSULATION (INCLUDING A.C. CORD), AND REPLACE IF NECESSARY
FOLLOWORIGINALLAYOUT,LEADLENGTHANDDRESS.
5. NO LEAD OR COMPONENT SHOULD TOUCH A RECEIVING TUBE OR A
RESISTOR RATED AT 1 WATT OR MORE. LEAD TENSION AROUND
PROTRUDINGMETALSURFACESMUSTBEAVOIDED.
6. ALLCRITICALCOMPONENTSSUCHASFUSES.FLAMEPROOFRESISTORS,
CAPACITORS,ETC. MUSTBEREPLACED WITH EXACT FACTORYTYPES,
DO NOT USE REPLACEMENT COMPONENTS OTHER THAN THOSE
SPECIFIEDORMAKEUNRECOMMENDEDCIRCUITMODIFICATIONS.
7. AFTERRE-ASSEMBLYOFTHESET,ALWAYSPERFORMANA.C.LEAKAGE
TEST ON ALL EXPOSED METALLIC PARTS OF THE CABINET, (THE
CHANNEL SELECTOR KNOB, ANTENNA TERMINALS. HANDLE AND
SCREWS)TOBESURETHESETISSAFETOOPERATEWITHOUTDANGER
OFELECTRICALSHOCK.DONOTUSEALINEISOLATIONTRANSFORMER
DURING THIS TEST, MAKE SURE TO USE AN A.C. VOLTMETER. HAVING
5000 OHMS PER VOLT OR MORE SENSITIVITY, IN THE FOLLOWING
MANNER; CONNECTA 1500 OHMS10 WATT RESISTOR, PARALLELED B Y
A.15MFD.150VA.C.TYPECAPACITORBETWEENAKNOWNGOODEARTH
GROUND (WATER PIPE, CONDUIT, ETC.) AND THE EXPOSED METALLIC
PARTS, ONE AT A TIME. MEASURE THE A.C. VOLTAGE ACROSS THE
COMBINATION OF 1500 OHM RESISTOR AND 15 MFD CAPACITOR.
REVERSE THE A.C.
PLUG AND REPEAT A.C. ANY VOLTAGE
MEASUREMENTS FOR EACH EXPOSED METALLIC PART. VOLTAGE
MEASURED MUST NOT EXCEED 75 VOLTS R.M.S. THIS CORRESPONDS
TO0.5MILLIAMPA.C.ANYVALUEEXCEEDINGTHISLIMITCONSTITUTESA
POTENTIALSHOCKHAZARDANDMUSTBECORRECTEDIMMEDIATELY.
THELIGHTNINGFLASH WITH APROWHEADSYMBOL.WI THIN AN
EQUILATERAL TRIANGLE,ISINTENDEDTO ALERT THE SERVICE
PERSONNELTOTHEPRESENCEOFUNINSULATED"DANGEROUS
VOLTAGE" THAT MAY BE OF SUFFICIENT MAGNITUDE TO
CONSTITUTEARISKOFELECTRICSHOCK.
THEEXCLAMATIONPOINTWITHINANEQUILATERALTRIANGLEIS
INTENDED TO ALERT THE SERVICE PERSONNEL TO THE
PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE
LITERATURE.
SAFETYCHECKS
SUBJECT:FIRE&SHOCKHAZARD
SUBJECTGRAPHICSYMBOLS
PLACETHISPROBE
ONEACHEXPOSED
METAL PART
SUBJECT:X-RADIATION
SUBJECT:IMPLOSION
SUBJECT:TIPSONPROPERINSTALLATION
1.BESUREPROCEDURESANDINSTRUCTIONSTOALLSERVICEPERSONNEL
COVERTHESUBJECTOF
2. ONLYFACTORY SPECIFIEDC.R.T ANODE CONNECTORS MUST BEUSED.
DEGAUSSINGSHIELDSALSOSERVEASANX-RAYSHIELDINCOLORSETS,
ALWAYSRE-INSTALLTHEM.
3. IT IS ESSENTIAL THAT SERVICE PERSONNEL HAVE AVAILABLE AN
ACCURATEANDRELIABLE HIGHVOLTAGE METER.THECALIBRATION OF
THE METER SHOULD BE CHECKED PERIODICALLY AGAINST A
REFERENCE STANDARD, SUCH AS THE ONE AVAILABLE AT YOUR
DISTRIBUTOR.
4. WHENTHEHIGHVOLTAGECIRCUITRYISOPERATINGPROPERLY,THEREIS
NO POSSIBILITY OF AN
5. WHEN TROUBLESHOOTING AND MAKING TEST MEASUREMENTS IN A
PRODUCTWITHAPROBLEMOFEXCESSIVEHIGHVOLTAGEAVOIDBEING
UNNECESSARILYCLOSETOTHEPICTURETUBEANDTHEHIGHVOLTAGE
SUPPLYDONOTOPERATETHEPRODUCTLONGERTHANITISNECESSARY
TOLOCATETHECAUSEOFEXCESSIVEVOLTAGE.
6. REFER TO HV. B+ AND SHUTDOWN ADJUSTMENT PROCEDURES
DESCRIBED IN THEAPPROPRIATE SCHEMATIC AND DIAGRAMS(WHERE
USED).
1. ALLDIRECTVIEWEDPICTURETUBESAREEQUIPPEDWITHANINTEGRAL
IMPLOSION PROTECTION SYSTEM, BUT CARE SHOULD BE TAKEN TO
AVOIDDAMAGEDURINGINSTALLATION,AVOIDSCRATCHINGTHETUBE.IF
SCRATCHEDREPLACEIT.
2. USEONLYRECOMMENDEDFACTORYREPLACEMENTTUBES.
1. NEVERINSTALLANYPRODUCTINACLOSED-INRECESS.CUBBYHOLEOR
CLOSELY FITTING SHELF SPACE,OVERORCLOSETOHEATDUCT,ORIN
THEPATHOFHEATEDAIRFLOW.
2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIO
INSTALLATIONS WHERE DEW IS A FACTOR, NEAR STEAM RADIATORS
WHERESTEAMLEAKAGEISAFACTOR,ETC.
3. AVOID PLACEMENTWHEREDRAPERIESMAYOBSTRUCTREARVENTING.
THE CUSTOMER SHOULD ALSO AVOID THE USE OF DECORATIVE
SCARVESOROTHERCOVERINGSWHICHMIGHTOBSTRUCTVENTILATION.
4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMERCIAL
MOUNTING KI T, MUST FOLLOW THE FACTORY APPROVED MOUNTING
INSTRUCTIONS.APRODUCTMOUNTEDTOASHELFORPLATFORMMUST
RETAINITSORIGINALFEET(ORTHEEQUIVALENTTHICKNESSINSPACERS)
TO PROVIDE ADEQUATE AIR FLOW ACROSS THE BOTTOM. BOLTS OR
SCREWS USED FOR FASTENERS MUST NOT TOUCH ANY PARTS OR
WIRING.PERFORMLEAKAGETESTONCUSTOMIZEDINSTALLATIONS.
5. CAUTION CUSTOMERS AGAINST THE MOUNTING OF A PRODUCT ON
SLOPING SHELF OR A TILTED POSITION, UNLESS THE PRODUCT IS
PROPERLYSECURED.
6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE ON ITS
MOUNTINGTOTHECARTCAUTIONTHECUSTOMERONTHEHAZARDSOF
TRYING TO ROLL A CART WITHSMALL CASTERS ACROSS THRESHOLDS
ORDEEPPILECARPETS.
7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR STAND WHICH
HASNOTBEENLISTEDBYUNDERWRITERSLABORATORIES,INC.FORUSE
WITH THEIR SPECIFIC MODEL OF TELEVISION RECEIVER OR
GENERICALLYAPPROVEDFORUSEWITHTV'SOFTHESAMEORLARGER
SCREENSIZE.
8.CAUTIONCUSTOMERSAGAINSTTHEUSEOFEXTENSIONCORDS.EXPLAIN
THAT A FOREST OF EXTENSIONS SPROUTING FROM A SINGLE OUTLET
CANLEADTODISASTROUSCONSEQUENCESTOHOMEANDFAMILY.
X-RADIATION.THEONLYPOTENTIALSOURCEOF
X-RAYS IN CURRENT T.V. RECEIVERS IS THEPICTURE TUBE. HOWEVER,
THIS TUBE DOESNOTEMITX-RYSWHENTHE HIGH VOLTAGE IS AT THE
FACTORY SPECIFIED LEVEL. THE PROPER VALUE IS GIVEN IN THE
APPLICABLESCHEMATIC.OPERATIONATHIGHERVOLTAGESMAYCAUSEA
FAILURE OFTHEPICTURETUBEORHIGHVOLTAGESUPPLYAND,UNDER
CERTAIN CIRCUMSTANCES, MAY PRODUCE RADIATION IN EXCESS OF
DESIRABLELEVELS.
X-RADIATION PROBLEM. EVERY TIME A COLOR
CHASSISISSERVICED,THEBRIGHTNESSSHOULDBERUNUPANDDOWN
WHILE MONITORING THEHIGH VOLTAGEWITHAMETERTOBECERTAIN
THATTHEHIGHVOLTAGEDOESNOTEXCEEDTHESPECIFIEDVALUEAND
THATITISREGULATINGCORRECTLY.WESUGGESTTHATYOUANDYOUR
SERVICEORGANIZATIONREVIEWTESTPROCEDURESSOTHATVOLTAGE
REGULATION IS ALWAYS CHECKED AS A STANDARD SERVICING
PROCEDUREANDTHAT THE HIGHVOLTAGEREADINGBERECORDEDON
EACHCUSTOMER'SINVOICE.
PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS
GOODEARTHGROUND
SUCH AS THEWATER
PIPE,CONDUIT,ETC.