LG T730BH User Manual Page 1

COLOR MONITORSERVICE MANUALWebsite:http://biz.LGservice.comE-mail:http://www.LGEservice.com/techsup.htmlCAUTIONBEFORE SERVICING THE UNIT, READ THE SA

BLOCK DIAGRAM- 1 0 -Power Input100~240V AC(50/60Hz)LineFilterDegaussingCircuit[ OSD Control ]SMPSControl(IC901) TILTControlCircuit6.3VE2PROM(IC402)5VH

DESCRIPTION OF BLOCK DIAGRAM- 11 -1. SMPS(Switching Mode Power Supply)When you turn on the power switch, the operatingfprocedure is as follows:. 6. X-

- 12 -15. Video Pre-Amp Circuit.This circuit amplifies the analog video signal from 0~0.7 V to 0~4 V. It is operated by taking the clamp, R,G,B drive

1. Preparation for Service AdjustmentGENERAL INFORMATIONAll adjustment are thoroughly checked and correctedwhen the monitor leaves the factory, but so

- 14 -4. DistortionScanning frequency : All Mode (Mode 1~4)Display image : Crosshatch patternHorizontal : 10 RowVertical : 8 RowA-B 2.0mm, C-D 2.0mmE

11-2. Adjustment of White Balance After finishing adjustment of cut off (back raster),approve "Color(15.0) Full white pattern".Adjust BDRV D

- 16 -3. Adjustment Using Service software Program(Adjustment Program)1. Adjustment for Factory Mode (Preset Mode).1) Display cross hatch pattern at M

4. EDID Data Edit Using Service software Program 4.1 Read and Modify EDID Data 1) Connector the monitor and adjust device as Figure1 2) Display color

- 18 -- 18 -220IBMCompatible PCPARALLEL PORTPower inlet (required)Power LEDST SwitchPower Select Switch(110V/220V)Control LineNot usedRS232CPARALLELV-

1 2CHECK D900 BRIDGE DIODE?CHECKC908(+) VOLTAGE145VDC at 110V input310VDC at 220V inputIC901, Q901CHECKD971, D961, D951, D904D941, D942, D906 ?CHECKFU

1. PICTURE TUBE Size : 17 inch DefIection Angle : 90¡Neck Diameter : 29.1 mmStripe Pitch : 0.25 mmFace Treatment : W-ARASC (Anti-Reflection andAnti

262. NO CHARACTERNO CHARACTERNONONONOTROUBLE IN CDT SOCKETTROUBLE INP301, SIGNAL CABLE,PC SIGNALTROUBLE INIC302, P301TROUBLE INIC303TROUBLE INIC304YES

CHECKSCREEN CONTROLKNOB OF FBTCHECK VOLTAGE AT D961 CATHODE (50V)D971 CATHODE (80V)D951 CATHODE (13V)D941 CATHODE(6.3V)?CHECKIC401 (MICOM) PIN 165V (H

CHECK IC601 PIN 7 (45V)?CHECK IC401 PIN 33, 34(SAWTOOTH WAVE)?CHECKIC601 Pin 3 (13V) ?- 22 -4. NO VERTICAL DEFLECTIONNO V-DEFLECTION(ONE HORIZONTAL

3CHECK IC401 PIN 45, 46 WAVEFORM?CHECK IC401 PIN , 50 ?CHECK Q941,Q951 CHECK IC401 (MICOM)PIN 52, 53 (H/V INPUT) SIGNAL?- 23 -5. TROUBLE IN DPM4Stand-

CHECK Q953 COLLECTOR VOLTAGE (0.5V)?CHECK P902?CHECK RL901?CHECK IC401 PIN 4 (5V)?6. NO DEGAUSSINGNO DEGAUSSINGNONONONOTROUBLE IN TH901, DEGAUSSING C

5 1820 2119Q705 drainwaveform is right?Q706 base, collectorwaveforms are right?Q719 drain waveform is right?IC401 Pin 18 waveform isright?- 25 -7. H_D

- 26 -9. TROUBLE IN H-LINEARITYUNBALANCED OF H-LIN.CHECKIC401 PIN 11, 12,13CHECK Q711~Q716?CHECK L703?TROUBLE IN IC401 (MICOM)TROUBLE INQ711 ~ Q716TRO

Check if AC Voltage of IC401 Pin 35waveform is VariableT701 pin 2 voltage is change with H frequency?The Voltage waveform Q706 Collectoris right?- 27

8 998Q501 Emitter output varieswith different DAC values? IC401 Pin 33, 34 output varies with differentDAC values?IC401 Pin 26 output duty varies wit

Q706 collecter waveformis right?15. High Voltage FailureNONOReplace T701Check Q719,Q720Check 50V lineRepeat the troubleshootingGuide of H_deflection

SAFETY PRECAUTIONS- 3 -SAFETY-RELATED COMPONENT WARNING!There are special components used in this color monitorwhich are important for safety. These p

22 23Some parts around T701are right?IC401 Pin 24output are right?Q710 and parts around are right?17. Focus FailureNONONOCheck the connection betwee

3 443IC401 Pin 23 input is High Active?All in/output values areright?IC401 Pin 45 and 46 inputs are right?IC401 Pin 16 input is over4.2V?18. Micom Fai

Proper Video levels areon P301 Pin 1, 3 and 5.IC401 Pins 27 and 28inputs are right at each function?20. User Control FailureCheck connector Ass’y.NOD

Blank pedestal is on Pin 19, 20 and 21 of IC302Is V_FLB and DC_bias onG1 Pin at CRT socket?G2 voltage is right?22. Visible RetraceCheck white balance

Improved focus?Adjust Pole4,Pole6to improve the misconvergence24. MisconvergenceDegauss the CDTDone.Change CRT and readjustconvergence.YesDoneNo25. Po

EXPLODED VIEW- 35 -1012121311-211-17BA265abb1 d1514153 9c8

EXPLODED VIEW PARTS LIST- 36 -Description CDT(CIRC), M41QEE903X 21 NDDP LG-PHILIPS 85KHZ 29.1MM FCDT TCO PLUS (T730BHKL) TILT SWIVEL ASSEMBLY, T710

- 37 -REPLACEMENT PARTS LISTCAUTION: BEFORE REPLACING ANY OF THESE COMPONENTS, READ CAREFULLY THE SAFETY PRECAUTIONS IN THIS MANUAL.* NOTE : S SAFE

*S *AL LOC NO. PART NO. DESCRIPTION/SPECIFICATONMODEL :T730BHKL DATE:2004.12.20MODEL :T730BHKL

MODEL :T730BHKL DATE:2004.12.20MODEL :T730BHKL DATE:2004.12.205.6BV 5MA PFZ D 4 0

- 4 -SERVICING PRECAUTIONSCAUTION: Before servicing receivers covered by thisservice manual and its supplements and addenda, readand follow the SAFETY

MODEL :T730BHKL DATE:2004.12.20MODEL :T730BHKL DATE:2004.12.20R 4 1 9 0 R N 4 7 0

*S *AL LOC NO. PART NO. DESCRIPTION/SPECIFICATONMODEL :T730BHKL DATE:2004.12.20MODEL :T730BHKL

- 42 -REPLACEMENT PARTS LISTCAUTION: BEFORE REPLACING ANY OF THESE COMPONENTS, READ CAREFULLY THE SAFETY PRECAUTIONS IN THIS MANUAL.* NOTE : S SAFE

*S *AL LOC NO. PART NO. DESCRIPTION/SPECIFICATONMODEL :T730SHKL DATE:2004.12.20MODEL :T730SHKL

MODEL :T730SHKL DATE:2004.12.20MODEL :T730SHKL DATE:2004.12.20C O I L s & C O

MODEL :T730SHKL DATE:2004.12.20MODEL :T730SHKL DATE:2004.12.20R 4 2 4 0 R D 1 0 0

*S *AL LOC NO. PART NO. DESCRIPTION/SPECIFICATONMODEL :T730SHKL DATE:2004.12.20MODEL :T730SHKL

- 47 -- 48 -SCHEMATIC DIAGRAMNOTICESince this is a basic schematic diagram.The value of components and some partial connection are sucject to be chang

- 50- DRAOB TIUCRIC DETNIRP)ediS tnenopmoC( DRAOB NIAM .3)ediS redloS( DRAOB NIAM .4)ediS tnenopmoC( DRAOB LORTNOC .1)ediS redloS( DRAOB LORTNOC .2 -

Dec 2004P/NO : 3828TSL109G Printed in China

- 5 -General Soldering Guidelines1. Use a grounded-tip, low-wattage soldering iron andappropriate tip size and shape that will maintain tiptemperature

- 6 -Circuit Board Foil RepairExcessive heat applied to the copper foil of any printedcircuit board will weaken the adhesive that bonds the foilto the

- 7 -TIMING CHART* No Composite Mode.H 37.50 26.67 20.32 6.35 0.51 2.03 3.81V 74.99 13.335 12.802 0.533 0.026 0.08 0.427H + 46.88 21.33 16.16 5.17 0.3

- 8 -DIS AS S E MB LY1. TIL T /S WIVE L & B AC K C OVE R R E MOVAL1) S et the monitor face downward.2) C arefully remove the Tilt/S wivel by

WIRING DIAGRAM- 9 -P501P201P405P301P302G2P702P701T1P402P902S+SSignal CableAC SocketFBTP203P202P220P904