LG Electronics TL-AT130M service manual Is 5V applied to the IC301 Pin 16, 40, 55, 58, 87?

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SECTION3 ELECTRICAL

ELECTRICAL TROUBLESHOOTING GUIDE

(3) When the C(Color) signal doesn't appear on the screen in PB Mode

Is 5V applied to the IC301

Pin 16, 40, 55, 58, 87?

Is the Color Rotary signal applied to

the IC301 Pin 10?

YES

NO

NO

Check the line of the 5.3VA

Line. (Power Circuit)

Check the Color Rotary Circuit. (IC501 pin 98)

Is Color Rotary "H" about

1.6V?

YES

NO		Check the Color Rotary level.
		(Check the R302, R303)
		(Check the R302, R303)

Does the Color signal appear at

the IC301 Pin 71?

YES

Replace the IC301.

NO	Does the X301(4.43MHz) or
	Does the X301(4.43MHz) or
	X302(3.58MHz) oscillate?

YES

Does the Color signal appear at the IC301 Pin 61?

YES

Check the circuit of the

IC301 Pin 35, 62.

NO

NO

NO

Replace the X301 or the X302.

Check the Color Pass. (Check the Q304)

Replace the IC301.

(4) When the Video signal doesn't appear on the screen in REC Mode.

Is the EE signal normal?

NO

Check EE Mode.

Is 5V applied to the IC301	NO		Check the line of the 5.3VA
Pin 16, 40, 55, 58, 87?			Line.(Power Circuit)
Pin 16, 40, 55, 58, 87?			Line.(Power Circuit)

YES

Does PB Mode operate

normally?

YES

Does the RF signal appear at

the IC301 Pin 12?

YES

Does the REC RF signal appear at

the IC301 Pin90?

YES

Check the Drum &

Drum Connector

NO

NO

NO

Check PB Mode.

Is the REC 'H' signal (about 4V)applied to the IC301 Pin 30?

YES

Check REC Luminance

Pass & Color Pass.

Check the circuit of the

IC301 Pin 90, 92, 94

NO

YES

YES

Check the System of REC 'H' (the IC501 Pin 30 / the D301)

Replace the IC301.

3-8

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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 When the drum moter stop Video is unstable in PB modePB mode 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 PB Mode No sound in EE Mode No sound in PB ModeNo sound in EE Mode Audio CircuitNo sound in REC Mode No sound in REC ModeSYSTEM/KEY Circuit Auto Stop No cassette tape loadingAuto Stop No OSD display No Key displayOSD Circuit 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-2-4Bracket Assembly L/D Motor Fig. A-2-4 Gear Assembly Rack F/L Fig. A-2-5Holder Assembly CST Fig.A-2-2 Arm Assembly F/L Fig. A-2-6Base Assembly A/C Head Arm AssemblyCleaner Head F/E Fig. A-3-2Arm Assembly Tension Fig. A-4-3 Brake Assembly T Fig. A-4-1Brake Assembly RS Fig. A-4-2 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-6-3Lever Spring Fig. A-7-6 Gear Sector Fig. A-7-3Lever Tension Fig. A-7-5 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 Tension Fig. A-9-2 Base Loading Fig. A-9-1 Arm Assembly Idler Fig. A-9-3Arm Assembly Idler Base Tension Base LoadingDeck Mechanism Adjustment Mechanism Alignment Position Check Fig. C-1Mechanism Condition Checking TorqueTest Equipment/ Fixture Test Conditions Torque Gauge 600g.cm ATG Cassette Torque Meter SRK-VHT-303Guide Roller Height Adjustment Head Assembly Audio/Control A/C Head AdjustmentAdjustment Procedure/Diagrams Head BaseAdjustment Procedure Adjustment Diagram Value AdjustmentPrecise Adjustment Azimuth adjustment 1KHZ 7KHZAdjustment after Replacing Drum Assembly Video Heads Check the Tape Travel after Reassembling Deck AssemblyCheck before starting repairs Maintenance Procedure Required MaintenanceScheduled Maintenance 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 LOCA.NO Description Specification Remarks Description SpecificationAssembly Section Remarks ScrewBuzzer LOCA.NO Description Specification Remark BATTERY,LITHIUMElectrecal section CapacitorLOCA.NO Description Specification Remark NP0 TS Coil DiodeFuse DigitronFilter HolderR121 0RD1800F608 R3G6 0RD1800F608 R553 0RD2200F608 R610 0RD2701F608 Switch LOCA.NO Description SpecificationRemote Controller Receiver Remark RESISTOR,DRAWINGTAL TransformerVaristor Zener Diode