LG Electronics TL-AT130M service manual Checking Torque, Test Equipment/ Fixture Test Conditions

Page 51

DECK MECHANISM ADJUSTMENT

2.Preparation for Adjustment (To set the Deck Mechanism of the loading state

without inserting a cassette tape).

1)Unplug the power cord from the AC outlet.

2)Disassemble the Top Cover and Plate Assembly Top.

3)Plug the power cord into the AC outlet.

4)Turn the power S/W on and push the Lever Stopper of the Holder Assembly CST to the back for loading the

cassette without tape.

Cover the holes of the End Sensors at the both sides of the Chassis to prevent a light leak.

Then the Deck Mechanism drives to the Stop Mode. In this case, the Deck Mechanism can accept inputs of each mode, however the Rewind and Review operation can not be performed for more than a few seconds because the Take-up Reel Table is in the Stop State and can not be detected the Reel Pulses.

3. Checking Torque

Purpose: To insure smooth transport of the tape during each mode of operation.

If the tape transport is abnormal, then check the torque as indicated by the chart below.

	Test Equipment/ Fixture	Test Conditions	Checking Method
		(Mechanism Condition)

•Torque Gauge(600g/cm ATG) • Play (FF) or Review (REW) Mode • Perform each Deck Mechanism mode without

• Torque Gauge Adaptor				inserting a cassette tape(Refer to above No.2
• Cassette Torque Meter				Preparation for Adjustment).
SRK-VHT-303			• Read the measurement of the Take-up or Supply
				Reels on the Cassette Torque Meter(Fig. C-3-2).
			• Attach the Torque Gauge Adaptor to the Torque
				Gauge and then read the value of it(Fig. C-3-1).

Item		Mode	Test Equipment		Measurement Reel	Measurement Values

Fast Forward Torque		Fast Forward	Cassette Torque Gauge		Take-Up Reel	More than 400g/cm

Rewind Torque		Rewind	Cassette Torque Gauge		Supply Reel	More than 400g/cm

Play Take-Up Torque		Play	Cassette Torque Meter		Take-Up Reel	40~100g/cm

Review Torque		Review	Cassette Torque Meter		Supply Reel	120~210g/cm

NOTE:			NOTE:

The values are measured by using a Torque Gauge and Torque Gauge Adaptor with the Torque Gauge affixed.

The torque reading to measure occurs when the tape abruptly changes direction from Fast Forward to Rewind Mode, when quick braking is applied to both Reels.

• Torque Gauge (600g.cm ATG)

• Cassette Torque Meter (SRK-VHT-303)

Torque Gauge

Torque Gauge Adaptor

Reel Table

S

R

T- H -V K

S

300
0	50

250

200
150	SRK
	SRK
VIDEO
CASSETTE
TORQUE
METER
VHT-
303

K -V H T - T
SR	0
	50
	100
	150
	200
	250
	300

Fig. C-3-1

Fig. C-3-2

4-14

Image 51

Contents KEY Table of Contents Summary Rear FrontVCR Function Indication Indicator PanelIN/OUT Description Terminal Signal LevelsSummary Critical Parts Replacing Time Table Cabinet & Main Frame Exploded Views Cabinet and Main Frame Section Cabinet & Main Frame Section Parts listPacking & Accessory Section Packing Accessory Section Parts listConnection chart of PG adjustment PG AdjustmentNo 24 Power CircuitSMPS No 5.3 aNo 5.2 a to AVCP, Bias Servo Circuit Video is unstable in PB modePB mode When the drum moter stopCapstan motor stops When the capstan motor stopsNo Video in EE Mode No Video in EE ModeC Circuit Pin 16, 40, 55, 58, 87? Clean the Drum Check the System Circuit IC501 PinIs 5V applied to the IC301 Pin 16, 40, 55, 58, 87? Is the EE signal normal?Audio Circuit No sound in EE Mode No sound in PB ModeNo sound in EE Mode No sound in PB ModeNo sound in REC Mode No sound in REC ModeSYSTEM/KEY Circuit Auto Stop No cassette tape loadingAuto Stop No F.OSD display No Key displayOSD Circuit No 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 Jack P.C.BOARD KEY 1 P.C.BOARD KEY 2 P.C.BOARDMechanism Part Fixing Type Top View Bottom ViewDrum Motor Drum Assembly Fig. A-1-1Fig. A-2-4 Plate Top Fig. A-2-1Arm Assembly F/L Fig. A-2-6 Gear Assembly Rack F/L Fig. A-2-5Holder Assembly CST Fig.A-2-2 Bracket Assembly L/D Motor Fig. A-2-4Head F/E Fig. A-3-2 Arm AssemblyCleaner Base Assembly A/C HeadReel S / Reel T Fig. A-4-4 Brake Assembly T Fig. A-4-1Brake Assembly RS Fig. A-4-2 Arm Assembly Tension Fig. A-4-3Arm 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 Lever F/R Fig. A-6-3 Brake Assembly CapstanJust lift the Plate Slider up Gear Sector Fig. A-7-3Lever Tension Fig. A-7-5 Lever Spring Fig. A-7-6Base Assembly P2 Fig. A-8-3/ Base Assembly P3 Fig. A-8-4 Gear Assembly P2 Fig. A-8-1/ Gear Assembly P3 Fig. A-8-2 Base Tension Base Loading Base Loading Fig. A-9-1 Arm Assembly Idler Fig. A-9-3 Arm Assembly Idler Base Tension Fig. A-9-2Deck Mechanism Adjustment Fig. C-1 Mechanism Alignment Position CheckTorque Gauge 600g.cm ATG Cassette Torque Meter SRK-VHT-303 Checking TorqueTest Equipment/ Fixture Test Conditions Mechanism ConditionGuide Roller Height Adjustment Head Base Audio/Control A/C Head AdjustmentAdjustment Procedure/Diagrams Head Assembly1KHZ 7KHZ Value AdjustmentPrecise Adjustment Azimuth adjustment Adjustment Procedure Adjustment DiagramCheck the Tape Travel after Reassembling Deck Assembly Adjustment after Replacing Drum Assembly Video HeadsCheck before starting repairs Cleaning Required MaintenanceScheduled Maintenance Maintenance ProcedureGreasing 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 Is the Belt ok? NonoFront Loading Mechanism Cassette does not load Exploded Views Moving Mechanism A11 NSP Not Service Part RUN DateParts Section Screw Description SpecificationAssembly Section Remarks LOCA.NO Description Specification RemarksCapacitor LOCA.NO Description Specification Remark BATTERY,LITHIUMElectrecal section BuzzerLOCA.NO Description Specification Remark NP0 TS Diode CoilHolder DigitronFilter FuseR121 0RD1800F608 R3G6 0RD1800F608 R553 0RD2200F608 R610 0RD2701F608 RESISTOR,DRAWING LOCA.NO Description SpecificationRemote Controller Receiver Remark SwitchZener Diode TransformerVaristor TAL