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Contents

Page

Contents
8. Alignments 9. Circuitdescription new circuitsand list of abbreviations 10. Sparepartslist

Page
47 52 61

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2 1. Technical Specifications instructions, 4 2. Safety-and maintenance warnings and notes. 6 for 3. Directions use 4. Mechanicalinstructions 9 5. Servicemodes,repairtips and faultfindingtrees 9 21 6. Wiringdiagram 22 l2C bus interconnection diagram 22t23 Supplyvoltagediagram Blockdiagram 24 Testpointsoverview oscillograms and 25 7. Electricaldiagram's en PWB's Diagram PWB (Diagram Powersupply 27/28 A1) 26 (Diagram42) 29 Horizontal deflection 27/28 (Diagram Verticaldeflection A3) 30 27128 (Diagram44) 30 27128 Synchronisation (Diagram Tuneren videolF A5) J I 27/28 Diversity 32 table45 (Diagram Video processing A6) 33 27128 (Diagram 27128 Control A7) 34 (Diagram Frontcontrol 27t28 A8) 35 (Diagram49) 36 AV Mono demodulator 27t28 (Diagram 27/28 Soundamplifier A10) J / (Diagram 1) 38 Headphone 41 27/28 (Diagram RearlO Cinches 27/28 A13) 39 (Diagram 40 41 CRT Panel B) (DiagramF) Externalpower supply 41 41 (Diagram 42 Clock Gl) 42 (Diagram Radio- SP/LS 42 Hl) 43 (Diagram Smartplug/ loudspeaker l) 45 45 (Diagram Smartcard intedace 46 44 J)

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OCopyright reseNed 2OOO PhilipsConsumer ElectronicsB.V. Eindhoven,The Netherlands. rightsreserved. part of this publication All No may be reproduced, storedin a retrieval systemor transmitted, any formor by any means,electronic, in photocopying, otherwise mechanical, withoutthe priorpermission Philips. of or by Published FM 0062 ServicePaCE Printedin the Netherlands Subjectto modification

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Technicat Specifications

1. Technical Specifications
1.1 Introduction:
1.1.1 Range LgH.2EChassis Basic:This executionis provided with a "Smartloader"and "Externalloudspeaker socket". Basicplus:Same as "Basic"and additional with "Teletext" ane "LEDClock". Basicplus radio: Sameas "Basicplus"and additional with "FM radio". System:Sameas "Basicplus"and additionala DCM interface panel To the DCM interface panelso called"smartcards"can be connected. For poweringthe smartcard also when the set is switchedoff, an externalpowersupplyis added inside. 1.1.2 Remote controls Two types of remotecontrolsare available: - StandardRemotecontrolfor normalconsumeruse: - So called"set-up" remotecontrol, type T374A,This remote works on RCSsystem7 code . With this remotecontrol specificnon consumerfunctions can be executed. 1.1.3 TV Commercial Consumermode / The softwaregivesthe possibilityto switchbetween "commercial" "consumer mode". and In the consumermode a limiteduser functionsare avaiable. Selection can be peformed with the set up remote. " Selection: Presson remote control 0 2 4I9 5 and MENUkey, then use the "left"or "right"key to selectCommercial or Consumermode. Highlight STOREand press"left"or "right" key to store changes.TV will go into standbymode after storing.

1.2

Specifications
Mainsvoltage : Mainsfrequency : powerconsumption Maximum : . 14" :40W +l- 1OV" . 20":56W +/- 10% , 2 1 " ' . 5 8 W+ / - 1 0 % : Standbypowerconsumption : Max.Antenne-input : Off air On air : Audio outout . S t e r e o : 2 . 3 W2 - l W ; . M o n o : 2 - 2 W : 4 W :3 W ;2 W ; 1 W 150V - 276Vac; 50 - 60Hz

10W +/- 10o/o 100dBV 90dBV

Tuners . uV 1316/4l-2 (PAL) . uv 1316/ArU-2 (PAL) . uv 1356c/Ar(PAL)

1.3

Specificationof the terminal sockets

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cL 86532104

VolumeChannel

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FoF 32 PIN SMART CAAD CONNECTION

BATHROOM SPEMER CONNECTION

SMART LOADEA CONNECTION

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Technical Specifications 1.4 Specification the terminalsockets of
1.4.3 Smart plug loader

. 1.4.1 Scart1: CVBS(in/out) RGB(in) tunerat output +

SMARTPLUG LOADER U1

PHONEJACK FORBATHROOM SPEAKER

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Clock Data-in +5V Data-out Ground lR-data '1,4 Speaker + 2 Speaker

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1 2 3 4 5 6 7 8

- AudioOut R - AudioIn R - AudioOut L - Earthscreen - Earthscreen - AudioIn L - Blue - CVBS status

(0.SVrms 1ka) < (0.2-2vrms1oko) > (o,svrms 1kQ) s (0.2-2vrms 1okQ) > (0.7vpp175C:) = = 4.5-7V (lNT O-ZV, EXT(16:9) , = EXT(a:3) 9.5-12V) (0.7Vpp/75o)

RJIl 1,4,4 Smart card connector

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9 - Earthscreen .10_ _ 1 1 -G r e e n 12__ 13- Earthscreen 14- Earthscreen 15- Red 16.FBL 17- Earthscreen 18- Earthscreen 19. CVBS 20. CVBS 21 - Earth süeen 1.4.2 Headphone

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32 PIN SMART CARO CONNECTOR

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(0.7Vpp/75o) (>0.9V RGBmode )

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PIN 17 ANALOG BLUE 18 ANALOGGREEN 19 ANALOG REO 20 FAST BLANKING 21 GROUNOCVBS-OUT 22 CVBS-OUT 23 AUDTOOUTMONO + 24 N.C. _ 25 AUDIOOUTMONO 26 GROUND IN AUDIO 27 AUDIO RIGHT OUT 28 AUDIOLEFTOUT 29 AUDIO RIGHT IN 30 AUDIO LEFTIN 31 CVBSry tN
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- Jack 3.5mm 8-600cr(4mW)

PIN 1 N.C. (POWEB) 2 GROUND 3 +Izveps (ilC) 4 GROUND 5 IR-DATA 6 PORFORDCM 7 TV-CLOCK 8 OCM.OATA 9 TV-DATA '10 +sveps 11 HORIZONTALSYNC 12 VERTICALSYNC 13 GROUND VBS-IN C 14 SCL2 15 SDA2 16 N.C.

1.5

PCBlocationdrawing

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POWERSUPPLY LINE DEFLECTION FRAMEDEFLECTION

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(SMARDPLUGLOAOER +LOUDSPEAKER SOCKET) TUNERVIDEOIF VIDEOPBOCESSING CONTROL INTERFACE SMARDCARD EPS (EXTERNAL POWER SUPPLY) SYSTEM SYSTEM FRONTCONTROL AM MONO DEMODULATOR SMARTSOUND+ IVIONO SOUNDAMPLIFIER HEADPHONE

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@g@Safetyinstructions,maintenanceinStruction,WarningSandNotes

warnings and Notes instruction, maintenance Safetyinstructions,
2.1 Safetyinstructionsfor repairsA
requirethat duringa repair: 1. Safetyregulations - The set shouldbe connected the mainsvia an to isolating ormer; transf - Satetycomponents, indicated the symbol A, by to shouldbe replacedby componentsidentical the originalones; - When replacing CRT, safetygogglesmust be the worn. 2. Safety regulationsrequire that after a repair the set musl attention In be returnedin its originalcondition. particular shouldbe paid to the followingpoints. - As a strictprecaution, adviseyou to resolder the we deflection solderjointsthroughwhichthe horizontal ('generalrepair currentis flowing,in particular instruction'): . All pins of the line outputtransformer (LOT); . Fly-backcapacito(s); . S-correctioncapacito(s); r Lineoutputtransistor; . Pins of the connectorwith wiresto the deflection coil; . throughwhichthe deflection Othercomponents currentflows. . Note: . This resoldering advisedto preventbad is due to metalfatiguein solderioints connections for sets and is thereforeonly necessary television olderthan 2 years. - The wire trees and EHT cable shouldbe routed correctlyand fixed with the mountedcable clamps. - The insulation the mainsleadshouldbe checkedfor of externaldamage. - The mains lead strainreliefshouldbe checkedfor its {unction in order to avoid touching the CRT, hot or comoonents heat sinks. - The electrical resistance betweenthe mains plug DC side shouldbe checked(onlyfor and the secondary This sets which have a mainsisolatedpowersupply). check can be done as follows: . Unplugthe mainscord and connecta wire betweenthe two pins of the mains plug; "on" position(keepthe . Set the mainsswitchto the mainscord unplugged!); . value betweenthe pins of Measurethe resistance of the mainsplugand the metalshielding the tuner on or the aerialconnection the set. The reading shouldbe between4.5 MO and 12 MQ . Switchoff the TV and removethe wire betweenthe two pins of the mainsPlug. - The cabinetshouldbe checkedtor defectsto avoid touchingof any innerpartsby the customer. . . on circuitry the Cleanthe powersupplyand deflection chassis. Clean the picturetube panel and lhe neck of the picture tube.

2.3

Warnings
1. ESDA to are 2. All lCs and many other semiconductors susceptible (ESD).Carelesshandlingduring discharges electrostatic make When repairing, repaircan reducelife drastically. as with the same potential the sure that you are connected mass of the set by a wristbandwith resistance.Keep and tools also at this same potential. components equipment: 3. AvailableESD protection - Completekit ESD3 (smalltable mat, Wristband, cable and Earthcable) Connection box, Extension 4822 310 10671 - Wristbandlestet 4822 344 13999 4. In order to prevent damage to lcs and transistors,all highmust be avoided.In orderto prevent voltageflashovers damageto the picturetube, the methodshown in Fig. 2.1 the picturetube. Use a highshouldbe usedto discharge (position DC-V).Discharge voltageprobeand a multimeter untilthe meter readingis 0V (afterapprox.30s). unit,the withthe deflection and any multipole unit 5. Together unit.The flat squarepicturetubes usedform an integrated at and the multipoleunitsare set optimally the deflection not otthis unitduringrepairis therefore factory.Adiustment recommended. in 6. Be carefulduringmeasurements the high-voltage sectionand on the picturetube. whilethe unit 7. Neverreplacemodulesor othercomponents is switchedon. 8. When makingsettings,use plasticratherthan metaltools. This will preventany short circuitsand the dangerof a circuitbecomingunstable. of 9. Wear saletygogglesduringreplacement the picture tube.

2.4

Notes
with shouldbe measured The directvoltagesand oscillograms regardto the tuner earth (+), or hot earth ($) as this is called. shown in the diagrams The directvoltagesand oscillograms and shouldbe measuredin the ServiceDefault are indicative Mode(seechapter8) with a colourbar signaland stereosound and picturecarrier (L:3 kHz, R:1 kHz unlessstatedotherwise) at 475.25 MHz. and directvoltagesare the Where necessary, oscillograms measuredwith (11-)and withoutaerialsignal()K;. Voltagesin the power supplysectionare measuredboth tor normal operation(O) and in standby1Ö;.fnese valuesare indicated symbols. by meansof the appropriate The picturetube PWB has printedsparkgaps.Eachsparkgap of is connectedbetweenan electrode the picturetube and the Aquadagcoating. in indicated the circuitdiagramand in the The semiconductors per with the partslistsare completely interchangeable position of in semiconductors the unit, irrespective the type indication on these semiconductors.

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2.2

Maintenanceinstruction
inspection carried It is recommended have a maintenance to The intervaldependson out by a qualified serviceemployee. the usageconditions: - Whenthe set is used undernormalcircumstances, for inlervalis 3 to examplein a livingroom,the recommended 5 years. - When the set is used in circumstances with higherdust, the greaseor moisturelevels,for examplein a kitchen, intervalis 1 Year. recommended - The maintenance actions: the inspection contains following 'generalrepair . Executethe above mentioned instruction'

warnings Notes instructions, Safety maintenance instruction, and

Figure 2-1

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instructions Mechanical

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the is The mono-carrier removedby pushing two centreclipsat both chassisbracketsoutwardsand pullingthe panelforward.

instructions 4. Mechanical
4.1

Servicepositions
See figure4-1 for the serviceposition. and Disconnectthe connecting cablefeedingthe right-hand the the left-hand speaker,also disconnect degaussingcable.

A
Figure4-1

B

CL 96532047_015.eps 280599

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protections, DST, faultfinding Modes, errormessages, 5. Service tips and repair
In this chapterthe followingparagraphs included: are 5.1 Testpoints 5.2 ServiceModes 5.3 The menusand submenus 5.4 Errorcode butferand errorcodes 5.5 The "blinkingLED" procedure 5.6 Customerservicemode ( CSM ) 5.7 ComPair 5.8 Orderingcompare 5.9 Troubleshootingtips Test pointsfor the Line deflection circuit( A2) . P1-P2-P3, etc.:Test pointsfor the powersupply( Al ) . S1-S2-S3, etc.:Test pointsfor the synchronisation circuit( (A4) . V1-V2-V3, etc.:Test pointsfor lhe videoprocessing circuit panel ( A6 ) and CRT panel ( B ) are underthe followingconditions: Measurements performed . Video:colourbar signal . audio:3kHzleft,lkHz right . Set in SDM mode

5.1

Test points
The main chassisis equippedwith test pointsin the service printing. Thesetest pointsare referring the functional to blocks: o A1-A2-A3, etc.:Test pointsfor the AM Mono Demodulator ( Ag ), ITT panel( D1) and Soundamplifier( D2 ) . C1-C2-C3, etc.:Test pointsfor the controlcircuit( 47 ) and the front control( A8 )

5.2

Servicemodes
The set has four servicesmodes: . ServiceDefaultMode (SDM) . ServiceAlignmentMode (SAM) . CustomerServiceMode (CSM) . COMPAIR mode

( F1-F2-F3, Testpoints theframe for deflection circuit etc.: A3) ( lF l1-12-13, Testpoints theTuner etc.: lor Video circuit A5)

5.2.1 Service Oefault Mode (SDM) The purposeof the SDM is:

@r@ServiceModes,DST,errormessageS,protections,fau|tfindingandrepair
. . . . providea situation with predefined settings get the same to measurements in this manual as start the blinkingLED procedure Settingof optionscontrols Inspectthe error buffer remainsdisplayed in top of screen).Pressing "MENU"key the againwill returnto the SDM mode. Figure5.'l ServiceDefaultMode screensand structure Exp Ian ati on n otes/rcfe re n ces: '1 "LLLL" . Operationhourstimer (hexadecimal) 2. Softwareidentification the main microcontroller of (LeHBBC X.Y) . LgH is the chassisname for L9H . BBC is 2 letterand 1 digitcombination indicate to the softwaretype and the supported languages: . X = (mainversionnumber) . Y = (subversion number)BB = (rangespecification ) 3. "SDM" To indicatethat the TV set is in the service default mode 4. "OP" OptionsCode whichexistsof 2 characters. is lt possibleto changeeach optioncode 5. "VALUE"The value of the selectedoption (ON/OFF or a combination 2 letters) of 6. "XXX" Valueof the optionsbytes ( OB1 .. OB7) 7. "ERR'The last five detectederrors;The left most number indicates most recenterrordetected. the The cursor Up or cursor DOWN commandcan be usedto selectthe nexVprevious option;The cursor LEFT and cursor RIGHTcommandcan be used to changethe optionvalue. Remark:When the option-code = OFF, the P+ and the PRC key have the same functionsas the cursor UP/DOWNkeys whilethe VOL+ and the VOL- key have the same functionas the cursorLEFT/RIGHT keys.When the optionRC = OFF it is not possible to changethe channelpresetor to adlustthe volumewhen in SAM/SDMmenu. Usinga Lg remotecontrol, RC option-code = ON, the P+, P-,VOL- and VOL+can be used to changethe presetand/orto adaptthe volume,while the keys are usedto selectthe optionand to change menu-cursor its value. For an extendedoverview the oDtion codessee Chapter8 of Ootions 5.2.3 Service Alignment Mode (SAM) alignthe The purposeof the SAM is to do tuningadjustments, whitetone, adjustthe picturegeometry and do sound adjustments. For recognition the SAM,"SAM"is displayed the top of the of at rightside of the screen Entering SAM: . By pressingthe "ALIGN" buttoncommandon the DST RC7150(DealerServiceTool) . When the set is in SDM by pressingthe menu key or the localkeyboardkeys "vol +" and "vol l simultantanously by >4 seconds. . Exit the SAM: Switchthe set to standbyor press EXIT on the DST (the enor bufferis cleared). Note:When the mains ooweris switchedoff whilethe set is in whenthe mainsis SAM,the set willswitchto SAM immediately switchedon again.( The error bufferwill not be cleared). In the SAM the followinginformation displayed the screen: is on

Entering the SDM: . By transmitting "DEFAULT" commandwiththe RC71 the 50 DealerServiceTool (thisworks both while the set is in normaloperationmode or in the SAM) . RCsequence (only 062596followed bythe key "MENU" via set up remote,T3744) The information on displayed the screenin the SDM mode is givenin fig. 5.1 (SDMmenu). Exit the SDM: Switchthe set to Standbyor press EXITon the DST (the error bufferis also cleared). Note:When the mains power is switchedoff whilethe set is in when the mains SDM, the set will switchto SDM immediately is switchedon again. ( The enor bufferwill not be cleared). Pre-defined conditions conditions: The SDM sets the followingpre-defined . PallSecam sets: tuningat 475.25PAL (For Franceselect the L'-signal ) . Volumelevelis set to 25"/"(ol the maximumvolumelevel). . Other pictureand sound settingsare set to 50%. in The followingfunctionsare "ignored" SDM sincethey interfere with diagnosing/repairingset. "lgnoring" a meansthat is the the eventthat is triggered not executed, settingremains unchanged. . (Sleep)Timer . Blue mute . Auto switch off . Hotelor Hospitality Mode . Child lock or Parentallock . presenVchannels Skipping, blankingof "Not favourite" . Automaticstoringof PersonalPresetsettings . Automaticuser menu time-out All other controlsoperatenormally. 5.2.2 Special functions in SDM Access to SAM By pressing "MENU"buttonon the remotecontroluntilSAM the (seefig.5.1) is presented.
LI]LL LgHBBC X.Y OP oB1 VALUE 0B2 0B3 xx 0B4 xx 0B5 xx 085 *x 087 SDM TV SETUP S

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Figure5-1 Accessto normal usermenu on Pressing "MENU" button the remote control the until the normal usermenu(TVSetup;for TV lock,Installation, "S" while Brightness, colour contrast is presented and )

ServiceModes,DST,errormeSSages,protections,fau|tfindingandrepair@r@

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Figure 5-2 Service Alignment Mode screens and structure Access to normal user menu Pressing "MENU"buttonon the remotecontrolwill the enterthe normaluser menu( TV lock,installation, brightness, colourand in contrast) while "SAM"remainsdisplayed top of screen. Pressing "MENU"key againwill returnto the last SAM the status. Access to SDM Pressing "DEFAULT" the buttonon the DST SAM menu control Menu items (AKB,VSD, Tuner,Whitetone, Geometryand Audio)can be selectedwith the cursor Up or cursorDOWN key. Entryinto the selecteditems (sub menus)is done by the cursor LEFT or cursorRIGHT key.The selecteditem will be highlighted. With the cursor LEFT/RIGHT keys, it is possibleto increase/ deceasethe value of the selecteditem.

@r@ServiceModes,DST,errormeSSageS,protections,faultfindingandrepair 5.3 The menusand submenus
5.3.4 Geometry sub menu The geometrysub menu containsthe followingitems: . SBL :Serviceblanking . VSL: Verticalslope . VAM : Verticalamplitude . VSH :Verticalshift . HSH : Horizontal shift . EW: E-W amplitude(onlyif optionEW=ep) . (onlyif optionEW=on) PW: E-W parabola/width . TC: E-W trapezium(onlyif optionEW=qn) . VSC : Verticalscroll(onlyif optionEW=onand 88=on) . VX: Verticalzoom (onlyif optionEW=6n; . CP: E-W cornerparabola(onlyif optionEW=on) . SC: S correction . H60 Delta HSH for 60H2. . V60 : DeltaVAM for 60H2. . W43: Delta EW for 4:3 (only if optionEW=en1 . S43: DeltaVSL for 4:3 . 443: DeltaVAM for 4:3 (onlyif optionEW=on) . C43: DeltaSC for 4:3 (onlyif optionEW=on) . X43: DeltaVX for 4:3 (onlyif optionEW=on)

5.3.1 Tunersub menu Thetunersubmenu contains followino the items:
lF PLL : PLL Alignment all PAUSECAM for systems,excluding SECAM-LL' . IF-PLLPos . lF PLL ofset . AFW : AFC Window . AGC : AGC take-overpoint . Y D : Defaultvalue = 12 ; Do not align . C L : Defaultvalue = 4 ; Do not align . AFA . AFB The itemsAFA and AFB can not be selected. thev are for purposes monitoring only. The commandscursor UP and cursorDOWN are usedto item. selectthe nexVorevious The commandscursorLEFT and cursorRIGHTare usedto increase/decrease valueof the selecteditem.The chanqed the valueswill be send directlyto the relatedhardware. The item valuesare storedin NVM if this sub menuis left. .

5.4
5.3.2 White tone sub menu
5,4.1 The commandsMENU UP and MENU DOWN are used to selectthe nexvorevious item. The commands MENULEFTand MENURIGHTare usedto increase/decrease valueof the selecteditem.The changed the valueswill be send directlyto the relatedhardware. The item valuesare storedin NVM if this sub menuis left. The white tone sub menu containsthe followinoitems: . NORMALRED . NORMALGREEN . NORMALBLUE . DELTACOOLRED . DELTACOOLGREEN . DELTACOOLBLUE . DELTAWARMRED . DELTAWARMGREEN . DELTAWARM BLUE OSD is keptto a minimumin this menu.in orderto make white tone alignmentpossible. The ContrastPlusfeature(blackstretch)is set to OFF when the white tone submenuis entered.

Errorcode bufferand error codes
Error code buffer The errorcode butlercontainsall errorsdetected sincethe last time the bufferwas erased.The bufferis writtenfrom left to right. o when an erroroccursthat is not yet in lhe errorcodebuffer, the error is writtenat the left side and all other errorsshift one positionto the right . the error code bufferwillbe clearedin the following cases: 1. exitingSDM or SAM with the "Standby" commandon the remotecontrol 2. transmitting commands"EXIT'with the DST the (RC7150) "DIAGNOSE-9-9-OK' the with 3. transmitting commands DST. the . The errorbufferis not resetwhen the set is switched by off the mainsswitch. Examples: . E R R O R0 0 0 0 0 : N o e r r o r s d e t e c t e d : . E R R O R6 0 0 0 0 : E r r o r c o d e Oi s t h el a s t a n d n l v : o detectederror . E R R O R5 6 0 0 0 : E r r o r c o d e 6 w a s f i r s t d e t e c t e d a n d : errorcode 5 is the last detected(newest)error

5.3.3 Audio sub menu
The audiosub menu (for stereosets only)containsthe followingitems: . ST-NT : Stereonoisetreshold(onlyif option SB=50) . : SAP noisetreshold(onlyif option SAP-NT SB=56; . L A : Inputleveladjust (onlyif option sB=s0/52155) : Stereoadjustforwidebandexpander WIDEB (only if optionS8=50/52155) : Stereoadjustfor specialexpander SPECT (onlyif optionSB=50/52l55) : Attacktime at AVL (onlyif option AT : StereoadjustMSP34xx(onlyif option SB=IT/NB/NDIT) The sound adjustments sub menu is not availablein Mono sets. The presenceof an item in the menu stronglydependson the selectedsound board(optionSB). 5.4.2

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Error codes faults,clearthe error bufferbefore In case of non-intermittent "old" the starting repairto preventthat errorcodesare present. checktheentirecontentof the errorbuffers.In some lf possible situations errorcode is only the RESULTof anothererror an code (and not the actualcause). Note:a fault in the orotection detection circuitrv can also lead to a protection. a. Error0 = No error b. Error 1 = X-ray ( Only for USA sets ) c. Error2 = High beam currentprotection - High beam protection active;set is switchedto protection; errorcode2 is placedin the errorbuffer;the LED will blink2 times ( repeatedly ). - As the name implies, causeof this protection a the is too high beamcurrent(brightscreenwith flyback lines).Checkwhetherthe +160Vsupplyto the CRT panel is present.lf the voltageis present,the most likelycause is the CRT panelor the picturetube. Disconnect CRT oanelto determine cause.lf the the

sB=52l55) STEREO

ServiceModes,DST,errormessa9eS,protections,fau|tfindingandrepair@r@
the +160Vvoltageis not present,check R3416and Deflection 42 ) D6409( Horizontal EW protection: is lf this orotection active.the causecouldbe one of the followingitems; . LOT5445 . S-correctioncaoacitot2407 . flyback capacilor 2434 . line outputstage . short circuit of tlyback diode 6434 . 7402 or drivertransistor Line uotputtransistor 7400 d. Error3 = VerticalGuard ( e. Error4 = Soundprocessor 1C7803 llC enor ( ) MSP3415D ) does not respondto the microcontroller Sound processor a. Error5 = Bimos( 1C7250 start-uperror ( POR bit ) ) or b. Bimosstart-upregisteris corrupted the llC line to the Bimosis alwayslow or no supplyat pin 12 of the Bimos). duringstart-up and hencewill This erroris usually detected preventthe set from startingup. c. Error6 = Bimos (TDA884x llC error ) Notethat this error may also be reportedas a resultof error codes 4 (in that case the Bimos mightnot be the actua. problem) a. Error7 = GeneralllC error.This will occur in the following
CASES:

5.6

ServiceMode(CSM) Gustomer
withthe "Customer ServiceMode"(CSM). The set is equipped the CSM is a specialservicemodeto identify statusof the set. with the set-upremote It can be activatedand deactivated (RG4172BK). The CSM is a 'readonly' mode, transmitter in thereforemodifications this mode are not possible.

5.6.1

"Commercial Entering the Customer Service Mode (in mode) The CustomerServiceMode can be switchedon by pressing RECALLon the set-upremotecontrolRG4172BK. When the CSM is activated: . pictureand sound settingsare set to nominallevels "Serviceunfriendly . modes"are ignored . buton>4 mode":RC "Mute"= localkeyboard In "Consumer secondssimultaneouslv

5.6.2

Exit the Customer Service Mode The CustomerServiceMode will switchoff after: . pressingone of the keys RECALLor MENUon the set-up remote control RG4172BK . otf switching the TV set with the mainsswitch. of All settingsthat were changedat activation CSM are set backto the initialvalues

SCL or SDA is shortedto qround SCL is shortedto SDA is SDA or SCL connection the microcontroller open at circuit. ( RAM error( A7 b. ErrorI = Microprocessor1C7600 internal ) .

5.6.3

The Customer Service Mode information screen on The followinginformation displayed screen: is

)
The microcontroller internalRAM test indicated errorof the an internalmemory(testedduringstart-up); microcontroller error( Checksum error); a. Error9 = EEPROMConfiguration EEPROM corrupted. is b. Error10 = llO errorEEPROM. NV memory(EEPROM) does not respondto the microcontroller Tuneris corrupted the llC c. Error11 = llC errorPLLtuner. or lineto the Tuner is low or no supplyvoltagepresentat pin I, pin 6 or pin 7 of the tuner.

I
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5.5

The "blinkingLED"procedure
The contentsof the error buffercan also be madevisible This is especially throughthe "blinking LED"procedure. useful when there is no picture.There are two methods: Whenthe SDM is entered, LEDwillblinkthe number the of times,equal to the value of the last (newest)errorcode (repeatedly). With the DST all error codes in the error buffercan be "DIAGNOSE madevisible. the x OK" Transmit command: wherex is the position the errorbufferto be madevisible in x rangesfrom 1, (thelast (actual) errofl to 5 (thefirsterror). The LED willoperatein the sameway as in point1, but now for the errorcode on position x. Examole: Errorcodepositionl 2 3 4 5 Enorbuffer:89 5 0 0 . afterenteringSDM: blink (8x) - pause- blink(8x) - etc. "DIAGNOSE- OK" with the DST blink . aftertransmitting 2(9x) - pause- blink(9x) - etc. "DIAGNOSE- OK'with the DST . aftertransmitting 3blink(5x) pause- blink(Sx) etc. "DIAGNOSE- OK'with the DST . 4aftertransmitting nothinghappens

1 2 3 4 6 7 8 9

HHHHLgHAP-X.Y CODES xx xx xx xx xx OP xxx xxx xxx xxx xxx SYS: AUTO AUTO MODE SMARTPORT CHANNEL

CSM xxx xxx

COMMERCTAL OFF TV1
CL96532141 _029.eps 071299

Figure 5-3 Fig 5-3 c196532141-O29Screen lay-outCSM A line numberis placedfor every line in order to make CSM languageindependent. Line 1: Operatinghours/SoftwareversionL9HBBCX.Yy Text "CSM";to indicatethat the set is in the Customer ServiceMode Line 2: Errorbuffercontents(see paragraph 5.4.2) (see chapter8) Line 3: Optioncode information Line 4: Configuration information. SYS: xxxx xxxx indicates colourand soundsystempreset the ". Line 5: " Not tunedwhen no signalis received Line6: not used whetherthe set is in commercial Line7: Mode.Indicates or consumermode Indicates Line 8: SmartPort. whetherthe Smart Port is selectedor nor. Indicates selected the channel. Line9: Channel.

@r@ServiceModes,DST,errormessageS,protections,fau|tfindingandrepair 5.7
5.7.1

GomPair
Introduction ComPair(Computer Aided Repair)is a servicetool for Philips products. ConsumerElectronics ComPairis a further development the DST serviceremotecontrolallowing on faster and more accuratediagnostics. ComPairhas three big advantages: . ComPairhelpsyou to quicklyget an understanding how to repairthe sets in shorttime by guidingyou step by step throughthe repairprocedures. . ComPairallowsvery detailed (on diagnostics l2Clevel)and problemareas. is therefore capableof accurately indicating You do not haveto know anythingabout l2C commands yourself;ComPairtakes care of this. . ComPairspeedsup the repairtime since it can automatically communicate with the sets (whenthe micro processoris working)and all repairinformation directly is available. When ComPairis installed togetherwith the SearchManelectronic manual,schematics and PCBsare only a mouse-click away. ComPairconsistsof a Windowsbasedfaultfindingprogram product. and an intedacebox betweenPC and the (defective) The ComPairinterface box is connected the PC via a serial to or RS232cable. In case of the L9H chassis,the ComPair interface box and the L9H communicate an llC cable (bivia (uni-directional; directional) and via infra red communication from ComPairinterface box to LgH. The ComPairfault findingprogramis able to determine the problemof the defective television. ComPaircan gather diagnostic information 2 ways: in (automatic) 1. Communication the television to 2. Askingquestions you (manually) to ComPaircombinesthis information with the reoairinformation in its databaseto find out how to repairthe set. A uto matic i nfom ation gatheri ng Readingout the error buffer,ComPaircan automatically read out the contentsof the entireerror buffer. Diagnosis l2C level.ComPaircan accessthe l2C bus of the on television. ComPaircan sendand receivel2Ccommands the to microcontroller the television. this way it is possiblefor of In (readand write)to deviceson the l2C ComPairto communicate bussesof the Manua I informati on gathe ri ng Automaticdiagnosis only possibleif the microcontroller is of the television workingcorrectly is and only to a certainextend. When this is not the case, ComPairwill guideyou throughthe faultfindingtree by askingyou questions and showingyou You can answerby clickingon a link (e.9.text or an examples. waveformpictures) that will bringyou to the next step in the process. faultfinding A questioncould be: Do you see snow? (Clickon the correct answer) YES / NO An examolecan be: Measuretest Doint17and click on the you see on the oscilloscope correctoscillogram

By a combination automaticdiagnostics of and an interactive question/answer procedure, ComPairwill enableyou to find most problemsin a fast and effective wav. Additional features Besidefault finding,ComPairprovidessome additiona featureslike: . Uploading/downloadingofpresets . Managingof presetlists . Emulation the DealerServiceTool of Connecting the ComPair inbrtace The ComPairBrowsersoftwareshouldbe installed and set-up beforeconnecting ComPairto the set. (See the ComPair BrowserQuick Reference Card for installation instructions.) 1. Connectthe RS232 interface cable to a free serial (COMM)port on the PC and the ComPairinterface PC connector(connector markedwith "PC").

2.

Placethe ComPairinteface box straightin frontof the television with the infraredwindow(marked"lR") directedto the television LED. The distancebetween ComPairinterface and television shouldbe between 0.3 and 0.6 meter.(Note:make sure that (also)in the serviceposition, ComPairinterface the inlra red windowis pointedto the standbyLED of the television set (no objectsshouldblockthe infra red beam) Connectthe mainsadaoterto the connectormarked "POWER9V DC" on the ComPairinterface Switchthe ComPairinterface OFF Switchthe television OFF with the mainsswitch set Removethe rear cover of the television set Connectthe interfacecable(4822727 21641\lolhe connector lhe rear side of the ComPairinterface on that is marked"12C" lsee Figure5.5) Connectthe other end of the interface cableto the (see figure5ComPairconnectoron the mono-carrier
ol

3.

4. 5. 6. 7.

L

Plug the mainsadapterin the mainsoutletand switch ON the interface. The greenand red LED light up together. The red LED extinguishes afterapprox.1 second(the green LED remainslit). Start-up ComPair and select"File"menu,"Open...:; select"L9.2 Faultfinding"and click "OK" Clickon the icon (fig. 5.6) to switchON the communication mode (the red LED on the ComPair interface lightup) will Switchon the television with the mainsswitch set When the set is in standby.Clickon "Start-up in ComPairmodefrom standby"in the ComPairL9Hfault findingtree, otherwisecontinue.

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10.

11.

12. 13.

1 V / d i vD C 1Ops div / Figure 5-4

ServiceModes,DST,errormessa9es,protections,faultfindingandrepair@r@

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Figure 5-5

5.9

TIPS TROUBLESHOOTING
In this paragraph some troubleshootingtips for the deflection For and powersupplycircuitry are described. detailed checkthe fault findingtree or use ComPair. diagnostics,

5.9.1

THE DEFLECTION CIRGUIT:
1 . Measurethe +VBATT( 95V) is presentacross2551 ( A2 -

Figure 5-6 The set has now startedup in ComPairmode. Followthe instruction the L9.H fault findingtree to diagnosethe set in Notethat the OSD works but that the actualuser controlis disabled

5.8

Ordering ComPair
ComPairordercodes: Starterkit ComPair+ SearchMan software+ ComPair intedace(excluding transformer)4822727 21629 : transformer): 4822727 ComPair intedace(excluding 21631 ComPair transf ormer (continental) Europe:4822727 21632 UnitedKingdom:4822727 21633 ComPairtransformer Starterkit ComPairsoftware: 4822727 21634 software: 4822727 21635 Starterkit SearchMan Starterkit ComPair+ SearchMan 4822727 software: 21636 SearchMan 4822727 21638 CD (update): ComPairinterface cable (for L9\:4822727 21641

Line deflection lf the voltageis not present,disconnect ). deflection stage is disconnected). lf coil 5551. (Horizontal the voltageis present thenthe problemmightbe causedby the deflection circuit.Possibilities: . Transistor 7402 is faultv . The drivercircuitaroundtransistor 7400 is faulty o No horizontal drive signalcomingfrom the BIMOS 7250-Dpin 40 ( 44 - Synchronisation ) . Timer-lC7607 or transistor 7608 is defect ( A7 Control) of hickNote:lf the Collector 7402 is shortedto the Emitter, up noisecan be heardfrom the powersupply.In this case the E/W protection disabled.is correctly is working( a parabolic picture) circuits the lineoutputstage. in Alsotake noteof protection lf any of thesecircuits activated, set will shut down, are the the Depending the protection, led will blinkaccording on to which protection the fault defined.In order to determine circuitis active,isolation each separate of circuitis necessary. These protection circuitsare: . ( High beam currentprotection LED blinksrepetitively ( 2 t i m e s ) - C R T p a n e lB ) . Verticalprotection LED blinksrepetitively times ) ( 3 ( Verticaldeflection A3 ) 5.9.2 THE POWERSUPPLY To troubleshootthe Lg SMPS,firstcheckthe Vaux voltageon C2561 lf this voltageis not present,checkf use F1572and . D6560.lf F1572or D6560is not opencircuit, problemmight the be causedon the primaryside of the switchingsupply.Check the outputof the bridgerectifier C2508for approximately on 300V DC at an input voltageof 230Vac.lf this voltageis missing,checkthe bridgediodes 6502 .. 6505 and the fuse 1500.lf fuse F1500 is foundopen,checkMOSFET 7518 to make sure that there is no short circuitpresentand check R3518.lf the 300V DC is presenton C2508,checkfor a startup voltageof approx.13V on pin 1 of 1C7520. no start-up lf voltageis present,check if R3510is open or diode 6510 is a short-circuit. is necessary havea feedbacksignalfrom the lt to hot primarysideof switchmodetransformerT554S pin 1 and at pin 2 for the powersupplyto oscillate. the start-up lf voltageof 13V is presenton pin 1 ot lC752O and the supplyis not oscillating, check R3529and D6540. Checkfor a drivesignalat the gate of MOSFET7518,square wave signal- P1. Checkpin 3 of 1C7520 and R3525. To determined whetherOVP is active.checkthe oresenceof Vaux at C2561.

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Figure 5-7

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protections, finding repair fault and Modes, DST,errormessages, Service

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Horizontal section Picture unstable horizontally. Picture widthtoo small. No sync. EAA/ ok not

Verticalsection pictureis Vertical too smallor unstable

1 3 5 0

(A4);, OK

(44); , OK

Check/ Replace (A4); tC725o

/ Check |leplace (Aa);lC ;7250

(A3);,, OK

Check/ Replace (42) TS7400,T57402, LOT 5445,C2407, (47) tC76O7, TS7608 Check/ Replace (A3); Vertical defl.coil L0222

Check/ Replace tc7460,R3463, R3465,R3466, D6460.C2464

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Figure5-11

1.eps CL 96532028_01

@r@ServiceModes,DST,errormeSsages,protections,fau|tfindingandrepair

Personalnofes.'

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I

I
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Alignments

@rw
. values(do not switchthe set to STANDBYfirst,this will changethe defaultsettingsof the set). SwitchON the set. Switchthe set to STANDBYto leave SDM.

8. Alignments
General:the ServiceDefaultMode (SDM)and Service AlignmentMode (SAM)are describedin chapter5.

8.1

conditions Alignment
All electricaladjustmentsshould be performed under the followingconditions: . :220V - 240V(10"/.) Supplyvoltage . Warm-uptime: 10 minutes . The voltagesand oscillograms measuredin relation are to the tuner earth. . Test probe:Ri > 10MQCi < 2,5 pF. . Patterngenerator(e.9. PM5518)set to 475.25 MHz systemfor your countrywith RF and.default transmission to of signalamplitude 1omVconnected the aerialinputof the TV. . SDM switchedon. 8.2.3

Focusing to Set the patterngenerator displaya Circlewith Small Squarespattern. Adjusted with focusingpotentiometer,positionedat LOT for of 5445 (see Fig.8.1), maximumsharpness the picture. VIEW MAINPANEL COMPONENT

o

:HoT GRoUND

I

8.1.1

Entering Service Default Mode (SDM) . . command withthe RC71 50 By transmitting "DEFAULT" the DealerServiceTool StandardRC sequence062596followedby the key "MENU"

, 8.1.2

Entering Service Alignment Mode (SAM) By pressing "ALIGN"button the command the RC7150 on DealerServiceTool when the set is in SDM by pressingthe MENU key unti, SAM is oresented

J tft
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1@0 TUNER

8.2
8.2.1

Alignments Electrical
Adjustment of the Power Supply to Set the patterngenerator displaya Circlewith Small Squarespattern. to 2409. Connecta DC voltmeter capacitor Adjustpotentiometer R3540 (see Fig.8.1)tillthe voltmeter indicates 95V.

I
o

Figure 8-1

8.3

Softwareadjustments

8.2,2 VG2
to Set the patterngenerator displaya blackpicture. ENtEr SDM. the MENU key on the RC SelectTV SETUPby pressing once. Pressthe MENU DOWN key on the RC untilthe BRIGHTNESS sub-menu selected is and changethe value to 50 with the MENU LEFI/BIGHT key. Selectthe CONTRASTsub-menuand changethe value to 0. the MENU key on the RC once. SelectSAM by pressing Pressthe MENU DOWN key on the RC untilsub-menu is VSD (Vertical Scan Disabled) selectedand changethe value from 0 to 1 by pressingthe MENU LEFT key. CAUTION!! Depending the position the VG2 potentioon of meter,a brightcolouredline will appearon the middleof the screenor the screenwill turn completely black. positioned LOT 5445 Adjustwith VG2 potentiometer, at (see Fig.8.1), untilthe coloured at the middle the line of screenis just not visible. The alignment the VG2 has beencompleted now.Switch of OFF the set usingthe mainsswitch.The valuesadaptedat the BRIGHTNESS- the CONTRASTsub-menuduring and the alignment, changeback againto their default will

8.3.1 Geometryadiustments
. Set the patterngenerator displaya Circlewith Small to Squarespattern. EnterSAM. SelectGEOMETRY menu. Usingthe MENUUPiDOWNkeyson the RC the respective itemsin the GEOMETRYmenu can be selected.Use the lefUrightbuttons to adjust the selecteditems to correct the picturegeometryas statedbelow.

Vertical Amplltude and Position . SelectVSL (VedicalSlope)and shiftthe pictureto the top. The text VSL and its value shouldbe at the upperhalf of the screen. . SelectSBL (Service Blanking) and set it to 1. The lowerhalf of the oicturewill be blanked. . Pressthe MENU UP key once to selectVSL and alignit to startthe blankingexactlyat the horizontal white line at the centreof the test circle.VSL has the correctvaluenow and shouldnot be changedanymore, Pressthe MENU DOWN key once to selectSBL and set it to 0. The full picturereappears.

@qf

@Atisnments
SelectVAM (Vertical Amplitude) and alignthe picture heightsuchthatthe top horizontal just disappears. line This corresponds with an over scan of approx.6%. SelectVSH (Vertical Shift)and aligntor verticalcentringof the pictureon the screen. Repeatthe last two steps if necessary. Select VSC (VerticalS-correction)to align the top/bottom squarestill they have the same size as the squaresin the middleof the screen. EnterWHITETONE menu and selectitem NORMAL, DELTAWARM, DELTACOOL or depending the item on which has to be aligned. The items R, G and B can be alignedaccordingpersonalpreference. The defaultvaluesfor the colourtemperature displayedin are the table below: NORMAL .

1 1 5 0 0 KR = 4 0

G=4O
f = U

B=4O
tt=o

DELTACJOOL 13500K t 1 = - 2

DELTAWARM8500K Horizontal Amplitude and Phase . SelectHSH (Horizontal Shift)and adjustit for a correct horizontal centringof the picture For sets with East/Westcoffection foltow the instructions below: SelectEWW (East-West Width)and alignthe picturewith substantial over scan. SelectEWT (East-West Trapezium) and alignfor a rectangleif necessary Parabola) SelectEWP (East-West and alignfor straight verticallines. SelectEWC (East-West Corner)and align the corners. Repeatif necessary. . Set H60to 10 and V60 to 10. . To storethe alignments the NVM, pressthe STANDBYin key on the RC. 8.3.2 AGC . . . . . . . Set the patterngenerator displaycolourbar pattern. to Connecta DC voltmeterat pin 1 of the tuner 1000. EnterSAM. EnterTUNERmenu. SelectAFW and align it for the lowestvalue. SelectAGC and adjustit untilthe voltageat pin 1 of the tuneris 1.0V+/- 0.1V. To storethe alignments the NVM, pressthe STANDBYin kev on the RC. 8'3'6 .

R = 2 G = 0 B=-7

To storethe alignments the NVM, pressthe STANDBYin key on the RC.

Audio (for stereo sets only) . . . . EnterSAM. EnterAudiomenu. Set A-FM to 232, set AT to 4, set STEREOto15 and set DUALtO15 To storethe alignments the NVM, pressthe STANDBYin key on the RC.

8.3.7

Option setting Optionsare used to controlthe presence absenceof certain / featuresand hardware. Via the remotecontrolthe optionscan be set when in SDM via two ways By settingeach singleoptioncode (two character-codes). By seüingthe decimalvalue of an option byte. Via an optionbyte a clusterof optioncodes can be set. There are 6 option bytes avaiable,see SDM menu, the first byte is numberedOB1 and the last byte is numberedOB7.

8.3.3 AFC
. . . ' . . . . to Set patterngenerator displaycolour bar pattern. EnterSAM. EnterTUNERmenu. SelectAFW and selectthe lowestvalue. "1" SelectlF-PLLand adjustit untilAFA becomes and AFB alternates between0 and 1. Switchlhe set to Standbyor procedewith nextitem in case of sets caoableof receivinqSECAM L'. Changethe signalat the patterngenerator SECAM to SelectIF-PLLPOS and adjustit untilAFA becomes1 AFB alternates between0 and 1. To storethe alignments the NVM, pressthe STANDBYin key on the RC.

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o

8.3.4 Tuner options CL, YD and IF-PLL OFFSET
. . . . Enter SAM. EnterTUNERmenu. to Set CL ot 4, set YD 12 and set lF-PLL-OFFSET 48. To storethe alignments the NVM, pressthe STANDBYin key on the RC. Note:No Alignmentneededfor lF-PLL(fixedvalue at 64).

8.3.5 White tone generator display Setthe pattern to colour andcircle bar pattern. Enter SAM.

Alignments

AAABBC X.Y

SAM

o

TUNER WHITE TONE GEOMETRY AUDIO AKB VSD

D

L9O BBC X.Y TUNER IF-PLL IF-PLL AFA AFB POS 1 L

a o

I
---->

1r
Jt

L9O BBC X.Y

I
L9O BBC X.Y SOUND A_FM AT STEREO

D

I t @r
SAM ----->

NORMAL RED

L9O BBC X.Y

D

J]
Figure 8-2

lr

I

VAM

1l JI
C1965321 41_028.eps 071299

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EEEE

@Atisnments

Option codes The variousoptioncodes and the descriptions the two of character-cooes exolainedbell W are )

upuon Symbol Option
IC

l'u tsus1

PS

Extra PowerSupply

BZ DI
RA SC

Buzzer
Display Module RadioModule Smartclock

SS
SP

Smartsound Smartpicture

DT WE
CH

Step tuning WestEurope

Oescription Enable/disable communication the RJ11 socKetand at the Smart 32-pinconnector. l'C at Set IC=OFFif the l2Cis not neededand no properpull-upresistors connected. are The Passive SmartLoader, whichalso uses this bus, will work even if IC=OFF. mustbe modified monitoring microprocessor. for by Set PS=ONwhen EPS is installed.The power-switch The TV software turn off trebleand bassfeatures. will Microprocessor ignorethe trebleand bass boost will circuits. to Port P2-0must be electrically Enable/disable tone generation the inputof the audiopoweramplifier. the connectedto the audio power amplifiertor buzzer to work. Enable/disable driverfor the EU Clock (LED displaymodule).lf DI=ON,lC must be ON. the radiomodule).It DI=ON,lC must be ON. Enable/disable driverfor the EU Radio(external the from a teletextcarryingchannel.TV softwareand of Enable/disable downloading the time-of-the-day the hardwaremust supportteletextinorderto use Smart Clock.(L9HAPand L9HANboth have teletext feature.) SmartSound.Trebleand bass boostcircuits(if available) also disabledif SS=OFF. are Enable/disable nable/disable Smart Picture. tuningis done uponentryof 2 digits(LgHAPand DT=ON,tuningis done uponentryof any digit. DT=OFF, channels 100and 125). below100or 3 digits(L9HANbetween L9HANchannel

cc
AC TP
GP

TN

FT
AA X1

x2

CD

NI

NR CP

CT EW
BS AS

Set WE=ONfor West Europe. Not used in L9HAPand L9HAN. in Set CH=ONfor tuner modulewith 38MHz lF (available ITV set model/93). Closedcaption close caption.Not used in L9HAPand L9HAN. Enable/disable tunedchanneland the operation this featurevia the A,/CH of key Alternate the channel Enable/disable storageof previously on the remotecontroller. of Channel the manaoement Enable/disable organization the channelsin rings (TV, PAYTV,INFO,and RADIO).lt TP=ON, is remoteRC2882/01 neededto operatethe set. group the of L;hannel Enable/disable organization the channelsin groupsor tiers.Not used in L9HAPand L9HAN. in Tuner Set TN=ON for Alps tuner module(available ITV set model/71). fine-tuning. Finetuning Enable/disable and auto switchingbetweenSCART1 of AV auto switching Enable/disable auto-detection S-videoat the SCARTconnector and SCART2. Not used in L9HAPand L9HAN,must be AA=OFF. for When AV1 Enableidisable external1 sourceinput(AV1).The connector AVI may or may not be available. sourceinputs. X1=ON,AV1 will be 1 of the user-selectable for When external2 sourceinput(AV2).The connector AV2 may or may not be available. AV2 Enable/disable to sourceinputs.lt is possible haveAV2 withoutAV1, i.e, set X2=ON,AV2 will be 1 of the user-selectable at slot AV2 can be available the 32-pinSmartCard butthereis no cinch X2=ONand Xl =OFF.For example, for AV1. The connector S-VIDEOmay or may not be for externalS-videosourceinput(S-VIDEO). AV2YC Enable/disable sourceinputs.The settingsfor X1, X2 When YC=ON,S-VIDEOwill be 1 of the user-selectable available. of it and YC are independent; is possibleto have any combination ON and OFF. Since S-VIDEOshares Selecting to S-VIDEO a AV2 implies forcedswitching AV2 at the videoprocessor. lineswithAV2,selecting betweenAV2 and Salso.There is no auto switching at will cause a forcedswitching the video processor VIDEO. duringauto-store. CD=ON,autoof automaticdetection cable and antenna(broaclcast) Auto cabledetect Enable/disable mode.CD=OFF,auto-store usesthe selected cable/broadcast storewill detectand set the cable/antenna mooe. 'l0 switchto standbyafter min of no video signaldetected. automatic No IDENTauto Enable/disable standby picture appearance the main menu and its usage in non-Smart in the Noisereduction Enable/disable noise reduction setting.Even if NR=OFF,it will still appearin the menu.(Thisoption may be deletedin future.) picturesetting.Even in the ContrastPlus Enable/disable ContrastPlusappearance the menuand its usagein non-Smart via if CP=OFF,it can still be controlled Smart picture.(Thisoptionmay be deletedin future.) picture in appearance the menu and its usage in non-Smart the Enable/disable Colourtemperature Colourtemoerature via setting.Even if CT=OFF,it can stillbe controlled Smart picture.(Thisoptionmay be deletedin future.) EW, PW, CP, TC, VX, VSC. Set EW=ONfor largescreen(25" and alignment, East-West functions Enable/disable east-west above)TV. standbymode of the video processor. Bimosstandby Enable/disable powersup mode of the video processor.lf AS=ON,the video processor the Bimosauto-startup Enable/disable auto-startup commandsthe video lf (and the TV circuits)basedon its own algorithm. AS=OFF,the microprocessor processor when to switchon. For minimumTV switchon time, must set AS=ON. China

I
O

Alignments
Option Symbol Option control Bass/Treble tsl

r t@
Description sound sefirng.wnen the Enable/disable bass and trebleitems in the menusand its usagein BT=OFF,the trebleand bass are at the defaultvalueswhen Smartsound is not availableor when it is in Even if BT=OFF,trebleand bass can still be modifiedvia Smart sound.(This PRESETor PERSONAL. optionmay be deletedin future.) and its usagein of the Enable/disable operation this featurevia the lNC. SURR.on the remotecontroller surroundis off. Even if IS=OFF,it can still be non-Smadsound setting.When IS=OFF,when incredible via controlled Smartsound.(Thisoptionmay be deletedin future.) When UB=OFF,ultra the Enable/disable ultrabass in the menuand its usagein non-Smafisoundsetting. via bass is 0. Even if UB=OFF,it can stillbe modified Smartsound.(Thisoptionmay be deletedin future.) when enabled Menu item AVL available when enabled of Possibility languageselection Defaultvalue is OFF =BG lfSY=TMorSY=TD,

S

lncredible surround

UB
LV

Ultrabass

Volume Automatic (AVL) Leveller
Duall/ll or SAP 3435 audioout Defaultsoundtype Soundtype Soundboard

DU
AO

o

SD
ö l

=l

=DK

=M = l D ,l a n d D K

1 1 l = T M , = B G = 1 = D K = M l f S Y = T D ,= B l , B G a n d l = B K , B G a n d D K 5

SB

I

SM SY

SmartPort System

MA, Mono All (no sound board) MS, Monowith stereoplayback(lTT BSP 3501C) ND, StereozCS/ NICAM(lTT MSP341sD_ND)DB,BTSCDBX(lTTMSP3415G) KS, Korea2CS (lTTMSP341sD-KS) Mono(lTT MSP 341SD_MM)EC, BTSC lT, German2CS (lTT MSP 341sD_lT) MM, Multi-Mono/Bilingual non-DBX(TDA 9851) when SM=ON. circuitmust be available SmartPort Enable/disable SmartPodcommunication. SS, SingleSystem SP, SingleSystemwith NTSC Playback TD, True Dual TM, True Multi

Setting option codes: . EnterSDM. . select withthe MENUuP/DowN keysthe optionto be set. . keys. Changeits setting with the MENU LEFT/RIGHT . To storethe alignments the NVM, pressthe STANDBYin key on the RC. Explenation of option bytes a of An optionbyte is a figure representing combination maximum8 optioncodes.When the valuaof this optionbyte is optioncodes are set. Optionbytes make it set the refereng possible to set very fast all options. The various option bytes are compiledas listedbelow.

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Calculation of an option byte way: in An optionbyte value is calculated the following x1 28+b7x64+b5x1 OBx=b8x1 6+b4x8+b3x4+b2x2+b1 Setting option bytes . EnterSDM. Selectwith the MENU UP/DOWNkeys the option byte (O81,OB2,etc.)to be set. Key in the calculated value. To storethe settingin the NVM, pressthe STANDBY-key on the RC. Somechangeswill onlytake affectafterthe set has been switchedOFF and ON with the mainsswitch (coldstart). Remark When optionRC = OFF, the P+ and the P- key on the remote controlhavethe samefunctions the MENUUP/DOWNkeys as whilethe VOL+ and the VOL- key havethe same functionas the MENU LEFT/RIGHT keys.When RC=OFF,it is not possibleto changethe channelpresetor to adjustthe volume in SAM/SDMwith the remotecontrol.

@fl

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Circuitdescription newcircuits

9. Circuitdescription newcircuits
9.1 Introduction
9.1.1 General The switchmode powersupply(FixedFrequency is mains ) isolated. The control1C7520 (MC44603A) producespulsesfor drivingFET 7518. Powersupplyregulation achievedby is usingduty cyclecontrolat a fixedfrequency nominalT0kqz of in normal operation. ln stand-by,slow-startand overload the situations SMPS runs at frequencies otherthan 70 kqz. Basiccharacteristics this SMPS : of . Mains lsolatedflybackConverter type . Inputrange : 150 - 276 VoltsAC . Secundaire voltageadjustment potentiometer via R3540at the primaryside . 1C7520 featured with Slow-Startcircuitrv is . Protection Circuits . Degaussing circuit 9.1.2 Output voltages . . . ( Audiosupply10V 114V( +18V ) for the Soundamplifier D2 becomeshigh-ohmic which reducesthe degaussingcurrent.Duringnormaloperation, degaussing the currentis signal.very small,becauseof the high impedance PTC of R3504. 9,2,2 Start up and take over Start-up: The start-upcircuitry consisting 3510,3530 of and 3529 use the voltagecomingfrom the 230V AC mains to start-up1C7520 the supplypin 1. The outputdrive via wavelorm(pin 3) is blockedby usingthe lcs internallogic untilthe voltageon pin 1 reaches14.5Volts howeverwith lessthan 14.5voltson Pin 1 the lC onlyconsumes0.3mA. Once pin 1 reachesthe 14.5 Voltsthreshold,1C7520 will start up (FET 7518 will conduct)and pin 1 sinks a typical supplycurrentof about 17 mA. This supplycurrentcannot be delivered the start-upcircuitry, a take-over by so circuit must be present.lf take-over does not occurthen the voltageon pin 1 will decreasebelowgV and 1C7520 will switchoff.The supplybeginsa new Start-upcycle,see top of this paragraph. This cycle will repeatitselfand can be noticedby an audiblehick-upsoundingnoise. . Take over : Duringstart-upa voltageacrosswinding1-2 is graduallybuiltup. At the momentthe voltageacross winding1-2 reachesapprox.(14.5Volts,D6540 start conducting and takes over the supplyvoltageVpin 1 of (takeover currentis approx.17mA). 1C7520 Note:This powersupplyis a FFS (= FixedFrequency Supply) PowerSupply). and not a SOPS (= Self Oscillating .

)
( VbatVMainSupply+95V ) for the Line deflection stage (42), Tunervideo lF ( A5 ) ( Vaux / MainAux( +9.5V) for the Line Deflection 42 ) and the Control(47)

9.1.3

The switching periods of TS7518 The powersupplyduty cycle is dependent the T-on of FET on 7518.The FET is drivenby pin 3 of lC752O. the This lC controls voltage(VBATTvia potentiometer secondary 3540.The primaryvoltageat pinl-2 of transformer by 5545 is rectified periodof D6537and smoothedby C2537.The switching TS7518can be dividedinto three main phases: Duty cycleTon, T-off and T-dead. . During T-on, FET 7518conducts. . Energyis storedin the primarywinding(4-7)of transformer primarycurrent.The T5545 by usinga linearincreasing slope depends on the rectified mains-voltagepresent acrossC2508.The T-on periodis variedto provide regulation the drivewaveformat pin 3 of 1C7520. of By controlling duty cycle of the SMPS in this way the the (VBATT is controlled. . DuringT-off, FET 7518 is switchedoff and thereforedoes not conduct.The energyis now transferred the to to secondary side of the transformer and then supplied the load via the secondarydiodes (D6550, D6560 and D6570). The currentthroughthe secondary side of the transformer decreasesuntilit reacheszero. . DuringT-deadFET 7518does not conduct.Thevoltageat the drain of the FET decays and eventuallyreachesthe inputvoltageof approximately 300v.

9.3
9.3.1

Controlcircuitry
1C7520 control mechanisms 1C7520 controlsthe T-on time of FET 7518 in three different ways: "Primary-voltage-sensing" o controlsthe secondary output voltagesvia the feedbackvoltagepin 14 "Primarycurrentsensing"controlsthe maximumprimary . currentvia the currentsense voltagepin 7 . "Demagnetization control"prevents transformer the T5545 from going into saturation the so-called"DEMAG" via functionat pin I

I
a

9.3.2

Secondary voltage sensing (pin 14 of 1C7520) (dueto a reduction Whenthe outputvoltage+VBATTincreases in the load ) the primaryvoltageat winding1-2 will increase, therefore voltageacrosscapacitor the 2537increases. This will reducethe on-timeof FET 7518 due to an increaseofthe voltagepresenton pin 14. In the event of an increaseof the load (decrease output of voltage+VBATT), the controlcircuitwill work in the opposite way to the explanation above. Primary sensing (pin 7 of 1C7520) The currentsensevoltageat pin 7 is usedto measurethe primarycurrentthroughFET7518. The primarycurrentis convertedinto a voltageby R3518.

9.2
9.2.1

Primary side
Mains input and degaussing Mains voltage: this voltage is filtered by L5500 and L5501, rectified the bridgediode6502 .. 6505 and then by smoothedby C2508whichprovidesa DC inputvoltageof 300V DC for an ac inputvoltageof 230V. "on"the set, Degaussing R3504is a PTC.Whenswitching : the PTC is cold and has a low-ohmic value.This allowsa very high degaussing currentat initialpower on. The PTC will then heat uD due to the hiqh currentinvolvedand

9.3.4

Demagnetizationcontrol (pin 8 of 1C7520) Winding1-2 has the same polarityas the secondary winding the that supplies load.When FET 7518 is turnedoff the voltage The powersupplytransfers at winding1 becomespositive. the

new circuits Circuitdescription
is storedenergyat the secondary side. Untilthe transformer At demagnetized voltageon the windingremainspositive. the the momentthat the energyis fullytransfenedto the load,the voltageat pin I of the transformer becomes negative. Additionally with a certaindead time the voltageat controlpin the B of lC 7520 also dropsbelowzero which releases output buffer(pin 3) and a new cycle starts. 9.3.5 Peak current limiting to An internalclamp at pin 7 allowspeak currentlimiting be achieved. This pin can never exceed1V DC and so the primary current through FET 7518,and alsothe maximum In maximumoutputpower is determined. case of an output beingshort-circuited loadedexcessively, l-primbecomes or the too high which is detectedby pin 7. As a resultthe primary currentis limitedto its maximumvalue and the secondary voltageswill drop. The voltageat pin 1, which is coupledwith the outputvoltage,will also drop. When the voltageat pin 1 and dropsbelowthe 9V, 1C7520 stopfunctioning the output will voltagewill rapidlydrop to zero. Via start-upcircuitry 3510,3530 and 3529 the voltage originating from the 230V AC mainsis usedto start-up1C7520 via the supplypin 1. As soonas this voltagereachesthe 14.5V, 1C7520 startstunctioning. the loadis stilltoo much or the lf outputis short-circuited samecyclewill happenagain.This the faultcondition can be clearlyidentified the powersupplywill as be loudly tripping. 9.3.6 Slow-start During the As soonas Vpin 1 > 14.5Vthe SMPSwillstart-up. procedure slow-start boththe frequency and the duty cyclewill be builtup slowly.The duty cyclewill initially slowlyincrease commencing with the absolutelowestpossibleduty cycle.The maximumduty cycle is determined C2530at pin 11 of by 1C7520, C2530is uncharged start-up. as at 9.3.7 Standby mode "reduced In standbymodethe SMPSswitches the so-called to frequency mode"and runsat about20 kHz. Duringstandby the SMPS only has to delivera minimallevelof outputpower.The levelis determined R3532at pin 12. by minimalloadthreshold In the L9 chassisthe SMPS does not have a burstmode in modeof about20 kHz as standbybut onlya reduced frequency statedabove. In normaloperationmode the internaloscillator is around70kHz. This lrequencyis controlled C2531at pin by 10 of 1C7520 and by R3537at pin 16 of 1C7520. standby In of modethe frequency operation determined R3536at pin is by 15 of 1C7520. 9.3.8 Protections Over voltage protection of the secondary voltages. After start-upthe supplyvoltagepin 1 will be "takenover" by winding1-2. Pin 1 of lC 7520 is usedto detectan over voltage situationon the secondary side of the transformer. this lf voltageexceeds17V (typical), the outputbufferis disabled, and a complete and lC 7520 goes into over voltageprotection restart sequenceis required. Checkin this case 1C7520, D6537 voltage+VBATT( +95V ). and the secondary R