LG Electronics TL-AT130M service manual Power CircuitSMPS No 5.3 a, No 24

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SECTION3 ELECTRICAL

ELECTRICAL TROUBLESHOOTING GUIDE

1. Power Circuit(SMPS)

(1) No 5.3 A

No 5.3V

NO

Is F101 normal?

Replace F101(Use a specified

(2) No 9V

No 12V

NO

YES

NO

Is BD101 normal?

YES

fuse).

Replace BD101.

Is D109 normal?

YES

Is Q170 normal?

YES

NO

Check/Replace D109

Replace Q170

Is R101 normal?				NO
Is R101 normal?


YES
YES

Is there Vcc (about 13~19V) at	NO
IC101 pin 5?

Replace R101.

Is D103 normal?

NO

Check/

Replace D103

NO

Is D110 normal?

YES

NO

Is Q152 normal?

YES

Check/ Replace Q163

Replace D110

Replace Q152

YES

Is D106 normal?

YES

NO

Replace D106.

(3) No 24 V

Is there about 2.5V at			NO
IC103 pin 1?
IC103 pin 1?

YES

Replace IC103.

No 24V

NO

Is D109 normal?				NO

YES				NO
YES

Is L103 normal?
Is L103 normal?

YES

Replace D109.

Is L103 normal?

Is D110 normal?

YES

Is Q159 normal?

YES

NO

Check/Replace D110

Check/Replace Q152

Check the power terminal at main

PCB short.

Check ‘H’ signal at Q161

Base terminal

3-2

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Contents KEY Table of Contents Summary Front RearIndicator Panel VCR Function IndicationTerminal Signal Levels IN/OUT DescriptionSummary Critical Parts Replacing Time Table Cabinet & Main Frame Exploded Views Cabinet & Main Frame Section Parts list Cabinet and Main Frame SectionPacking Accessory Section Parts list Packing & Accessory SectionPG Adjustment Connection chart of PG adjustmentPower CircuitSMPS No 5.3 a No 24No 5.2 a to AVCP, Bias Video is unstable in PB mode PB modeWhen the drum moter stop Servo CircuitWhen the capstan motor stops Capstan motor stopsNo Video in EE Mode No Video in EE ModeC Circuit Clean the Drum Check the System Circuit IC501 Pin Pin 16, 40, 55, 58, 87?Is the EE signal normal? Is 5V applied to the IC301 Pin 16, 40, 55, 58, 87?No sound in EE Mode No sound in PB Mode No sound in EE ModeNo sound in PB Mode Audio CircuitNo sound in REC Mode No sound in REC ModeSYSTEM/KEY Circuit Auto Stop No cassette tape loadingAuto Stop No Key display OSD CircuitNo OSD display No F.OSD displayElectrical Block & Circuit Diagrams Power Block Diagram Power Clrcuit Diagram Audio Block Diagram C Block Diagram V Circuit Diagram Electrical Block & Circuit Diagrams System Block Diagram Electrical Block & Circuit Diagrams System Clrcuit Diagram Jack Clrcuit Diagram KEY-BOARDCLRCUIT Diagram Electrical Printed Circuit Diagrams KEY 1 P.C.BOARD KEY 2 P.C.BOARD Jack P.C.BOARDMechanism Top View Bottom View Part Fixing TypeDrum Assembly Fig. A-1-1 Drum MotorPlate Top Fig. A-2-1 Fig. A-2-4Gear Assembly Rack F/L Fig. A-2-5 Holder Assembly CST Fig.A-2-2Bracket Assembly L/D Motor Fig. A-2-4 Arm Assembly F/L Fig. A-2-6Arm Assembly CleanerBase Assembly A/C Head Head F/E Fig. A-3-2Brake Assembly T Fig. A-4-1 Brake Assembly RS Fig. A-4-2Arm Assembly Tension Fig. A-4-3 Reel S / Reel T Fig. A-4-4Arm Assembly Pinch Fig. A-5-3 Opener Lid Fig. A-5-2Lever T/up Fig. A-5-4 Arm T/up Fig. A-5-5 Brake Assembly Capstan Lever F/R Fig. A-6-3Gear Sector Fig. A-7-3 Lever Tension Fig. A-7-5Lever Spring Fig. A-7-6 Just lift the Plate Slider upGear Assembly P2 Fig. A-8-1/ Gear Assembly P3 Fig. A-8-2 Base Assembly P2 Fig. A-8-3/ Base Assembly P3 Fig. A-8-4Base Loading Fig. A-9-1 Arm Assembly Idler Fig. A-9-3 Arm Assembly IdlerBase Tension Fig. A-9-2 Base Tension Base LoadingDeck Mechanism Adjustment Mechanism Alignment Position Check Fig. C-1Checking Torque Test Equipment/ Fixture Test ConditionsMechanism Condition Torque Gauge 600g.cm ATG Cassette Torque Meter SRK-VHT-303Guide Roller Height Adjustment Audio/Control A/C Head Adjustment Adjustment Procedure/DiagramsHead Assembly Head BaseValue Adjustment Precise Adjustment Azimuth adjustmentAdjustment Procedure Adjustment Diagram 1KHZ 7KHZAdjustment after Replacing Drum Assembly Video Heads Check the Tape Travel after Reassembling Deck AssemblyCheck before starting repairs Required Maintenance Scheduled MaintenanceMaintenance Procedure CleaningGreasing Chassis Bottom Chassis TopGear Sector Gear Cam Base Loading Gear Drive Lever, F/R, Base, Tension Gear AY, P2 & P3Base, Tension Mechanism Troubleshooting Guide Auto Stop PLAY/CUE/REV Nono Is the Belt ok?Front Loading Mechanism Cassette does not load Exploded Views Moving Mechanism A11 NSP Not Service Part RUN DateParts Section Description Specification Assembly Section RemarksLOCA.NO Description Specification Remarks ScrewLOCA.NO Description Specification Remark BATTERY,LITHIUM Electrecal sectionBuzzer CapacitorLOCA.NO Description Specification Remark NP0 TS Coil DiodeDigitron FilterFuse HolderR121 0RD1800F608 R3G6 0RD1800F608 R553 0RD2200F608 R610 0RD2701F608 LOCA.NO Description Specification Remote Controller Receiver RemarkSwitch RESISTOR,DRAWINGTransformer VaristorTAL Zener Diode