Emerson 6420FE service manual Precautions during Servicing

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Precautions during Servicing

A.Parts identified by the ( #) symbol are critical for safety.

Replace only with part number specified.

B.In addition to safety, other parts and assemblies are specified for conformance with regulations ap- plying to spurious radiation. These must also be replaced only with specified replacements.

Examples: RF converters, RF cables, noise block- ing capacitors, and noise blocking filters, etc.

C.Use specified internal wiring. Note especially:

1)Wires covered with PVC tubing

2)Double insulated wires

3)High voltage leads

D.Use specified insulating materials for hazardous live parts. Note especially:

1)Insulation Tape

2)PVC tubing

3)Spacers

4)Insulators for transistors.

E.When replacing AC primary side components (transformers, power cord, etc.), wrap ends of wires securely about the terminals before solder- ing.

F.Observe that the wires do not contact heat produc- ing parts (heatsinks, oxide metal film resistors, fus- ible resistors, etc.)

G.Check that replaced wires do not contact sharp edged or pointed parts.

H.When a power cord has been replaced, check that 5~6 kg of force in any direction will not loosen it.

I.Also check areas surrounding repaired locations.

J.Use care that foreign objects (screws, solder drop- lets, etc.) do not remain inside the set.

K.Crimp type wire connector

The power transformer uses crimp type connec- tors which connect the power cord and the primary side of the transformer. When replacing the trans- former, follow these steps carefully and precisely to prevent shock hazards.

Replacement procedure

1)Remove the old connector by cutting the wires at a point close to the connector.

Important: Do not re-use a connector (discard it).

2)Strip about 15 mm of the insulation from the ends of the wires. If the wires are stranded, twist the strands to avoid frayed conductors.

3)Align the lengths of the wires to be connected. In- sert the wires fully into the connector.

4)Use the crimping tool to crimp the metal sleeve at the center position. Be sure to crimp fully to the complete closure of the tool.

L.When connecting or disconnecting the internal connectors, first, disconnect the AC plug from the AC supply outlet.

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L6115IMP

Image 6 Contents
6420FE EWF2004 Important Safety Notice Table of ContentsDBµv SpecificationsDescription Condition Unit Nominal Limit DBµv AFT Pull In Range 10mV input MHz ±2.0 ±0.7Not be Above 0.5 mA Important Safety PrecautionsSafety Precautions for TV Circuit L6115IMPL6115IMP Precautions during Servicing Safety Check after Servicing Clearance DistanceLeakage Current Test Circuit Board Indications How to Remove / Install Flat Pack-ICStandard Notes for Servicing Pb Lead Free SolderMasking Flat Pack-IC Tape Tweezers With Iron WireMachine With Soldering IronInstallation Pin 1 of the Flat Pack-IC Is indicated by a markPresolder Ground for Workbench Instructions for Handling SemiconductorsGround for Human Body IncorrectDisassembly Method Cabinet Disassembly InstructionsDisassembly Flowchart Reference Notes in the TableRear Cabinet Rear Cabinet Main CBACRT TV Cable Wiring Diagram +B Adjustment Electrical Adjustment InstructionsHow to set up the service mode Service modeInitial Setting GeneralSD Check Mode F0 AdjustmentBlack Stretch Control Adjustment Purity Check10. V. Position Adjustment Position AdjustmentSize Adjustment Software ResetMode Input Cut-off AdjustmentWhite Balance Adjustment Tape SpecSub-Brightness Adjustment Focus AdjustmentPurity Adjustment Convergence Adjustment FiguresBlock SystemIF/Video Block Diagram L2401BLIFAudio L2401BLABlock Diagram CRT/H.VDiagram L2401BLPSchematic Diagrams / Cbas and Test Points Standard NotesTolerance of Capacitors are noted with the following Is not consistent here Wire ConnectorsHow to read converged lines Test Point InformationMain 1/4 Schematic Diagram L2401SCM1Main 2/4 Schematic Diagram L2401SCM2Main 3/4 Schematic Diagram L2401SCM3Main 4/4 & CRT Schematic Diagram Main 4/4 Ref No PositionMain CBA Top View BL2700F01012-1Main CBA Bottom View Q1511 Q1511 Collector Base CRT CBA Top ViewQ1521 Q1521 Collector Base Q1531 BaseWaveforms WF4WF9 CollectorWiring Diagram L2401WIPin Signal Name Function IC PIN FunctionsIC111 TV Micro Controller AFT Voltage Input White Balance AdjustmentJudgement Degaussing Coil ControlExploded Views Cabinet11-1 11-2 L2401CEX Packing X-2 X-3 Tape Packing Tape 11-3 L2401PEXMechanical Parts List Comparison Chart of Models and Marks20040405 12-1 L2401CA Electrical Parts List 20040405 13-1 L2401EL20040405 13-2 L2401EL Electrolytic CAP .33∝F/50V M CE1JMASDLR33Connectors 20040405 13-3 L2401EL20040405 13-4 L2401EL ICS20040405 13-5 L2401EL Transistor 2SC2120-YTPE220040405 13-6 L2401EL Switches 20040405 13-7 L2401EL20040405 13-8 L2401EL RCA Jack 1P AV-8.4-9W6420FE/EWF2004 L2401UB/L2404UE