CRT/Yoke Assemblies Remove and Replace | JVC 250 specification

Chapter 5---Electronics

CRT/Yoke Assemblies - Remove and Replace

Three CRT/Yoke Assemblies are located in the CRT Assembly area below the card cage (see Figure 5-30).

WARNING!!! Handle the CRT/Yoke Assemblies with extreme caution. If they are dropped, they can implode and flying glass can cause severe injury to personnel. Be careful not to bump or drop the CRT. Immediately after removal, place the CRT/Yoke in a safe area.

Procedure to remove a CRT/Yoke Assembly:

Tools Needed

#0 Pozi-drive Phillips-head screwdriver

Parts Needed

CRT p/n 105199

To remove and replace a CRT:

1.Power OFF the projector by IR Remote or PC, and allow the cooling fans to run until they shut off automatically.

2.Turn the AC Circuit Breaker to the OFF position and unplug the AC Power Cord.

3.Remove front and rear covers.

4.Tilt the Electronic Module up and lock it in place.

5.Loosen the two Pozi-drive Phillips-head screws from the top of the High Voltage Power Supply cover. Remove the one Pozi-drive Phillips-head screw at the bottom of the cover.

6.Remove the CRT Anode cable of the CRT being replaced from the High Voltage Power Supply.

7.Disconnect the Yoke plug and cable harness from the Scan Reversal PCB for the appropriate CRT (see Figure 5-25).

8.Remove the wires from the cable clamp for the CRT/Yoke Assembly being removed.

9.Loosen the CRT Holder Ring (knurled knob in Figure 5-29).

NOTE: The CRT Holder Ring should be only hand-tight. If it is not possible to remove by hand, place a Flathead screwdriver in the slots on the CRT Holder Ring and tap lightly to help loosen it. Do not use a tool of any kind to tighten this ring - hand tighten only.

10.Carefully remove the CRT/Yoke Assembly by sliding it backward and upward as far as possible before unplugging the CRT socket connector from the neck.

Model 250 Service Manual

5-57

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JVC 250 service manual CRT/Yoke Assemblies Remove and Replace

Contents

Model 250 Projector Declaration of Conformity Manufacturer Hughes JVC Table of Contents Software and Protocol TroubleshootingParts Contents Safety Updates Acronyms Used Secam Contents Introduction Power Supplies Incoming Power CircuitElectrical Section Igniter Assembly Optical SectionArc Lamp Module Optical Path ILA s Image Light Amplifier CRTs Electronic Section Relay Lens AssembliesFront Projection Lens Input Cards VICs Printed Circuit Boards PCB Miscellaneous Items EMI Shield System Description Safety Electrical Incoming Power Circuit AC Power CordAC Circuit Breaker AC EMI Filter Power Supplies Low Voltage Power Supply LvpsLvps Main Functions Lvps Inputs 1Low Voltage Power Supply I/O Diagram Lvps Operation Arc Lamp Power Supply Alps Lvps Service AdjustmentsLvps Remove and Replace Alps Main Functions Alps Inputs Alps Outputs 2Arc Lamp Power Supply signals and voltages Alps Operation Alps Service Adjustments Alps Remove and Replace High Voltage Power Supply Hvps Hvps Main Functions Hvps Inputs Hvps Outputs Hvps Service Adjustments Hvps Operation 5High Voltage Power Supply cover Hvps Remove and Replace PIN # Electrical Igniter Assembly Igniter Assembly InputsIgniter Assembly Outputs Igniter Assembly Operation Igniter Assembly Service Adjustments Igniter Assembly Remove and Replace Electrical Optical Arc Lamp Service Adjustments Arc LampArc Lamp Main Functions Arc Lamp Inputs Optical 2Arc Lamp alignment fixture 3Arc Lamp Assembly access door Arc Lamp Remove and Replace Optical Optical Path Optical Path Main Function Optical Path Outputs Optical Path InputsOptical Path Operation Optical 6Optical Path Optical Path Service Adjustments 7Optical Path 8XY Positioner adjust holes ILA ILA Main functionsILA Inputs ILA Outputs ILA Service Adjustments ILA Operation Optical Optical Optical Optical ILA Remove and Replace Relay Lenses Projection Lens Optical Optical Electronics 1Model 250 System Block Diagram System Controller PCB System Controller PCB Main Function Electronics Electronics 5System Controller PCB I/O Diagram for other PCBs System Controller PCB Inputs System Controller PCB Outputs System Controller PCB Operation Electronics System Controller PCB Remove and Replace Video Processor PCB Main Functions Video Processor PCBVideo Processor PCB Inputs 7Video Processor PCB I/O diagram for VICs and Power Supplies 8Video Processor PCB I/O diagram for PCBs Video Processor PCB Outputs Video Processor PCB Operation 9Video Processor PCB LEDs Video Processor PCB Remove and Replace Raster Timing Generator PCB Raster Timing Generator PCB Main Functions 11Raster Timing Generator for other PCBs Raster Timing Generator PCB Inputs Raster Timing Generator PCB Outputs Raster Timing Generator PCB Operation 12LEDs on the Raster Timing Generator PCB Raster Timing Generator PCB Remove and Replace Horizontal Vertical Deflection PCB Main Functions Horizontal Vertical Deflection PCBHorizontal Vertical Deflection PCB Inputs 13Horizontal/Vertical I/O Diagram Electronics Horizontal Vertical Deflection PCB Outputs Horizontal Vertical Deflection PCB Operation Horizontal Vertical Deflection PCB Service Adjustments 16Red image needs vertical adjustment decrease Electronics Horizontal Vertical Deflection PCB Remove and Replace Convergence Deflection PCBConvergence Deflection PCB Main Functions Convergence Deflection PCB Inputs Convergence Deflection PCB Outputs 19Convergence Deflection PCB I/O Diagram 20Convergence Deflection PCB I/O Diagram 21Physical layout of the Convergence/Deflection PCB Convergence Deflection PCB Operation Convergence Deflection PCB Remove and Replace Scan Reversal PCB Main Functions Scan Reversal PCBScan Reversal PCB Inputs Scan Reversal PCB Outputs 22Scan Reversal PCB I/O Diagram Electronics 24Scan Reversal PCB I/O Diagram for CRT Yokes Scan Reversal PCB Operation Electronics Scan Reversal PCB Service Adjustments Electronics 1Projection orientation jumper settings Scan Reversal PCB Remove and Replace Video Amplifier PCBVideo Amplifier PCB Main Functions Video Amplifier PCB Inputs 26Video Amplifier PCB I/O Diagram Video Amplifier PCB Outputs Video Amplifier PCB Operation Video Amplifier PCB Remove and Replace Electronics 28Video Amplifier PCB showing CRT Socket Connectors 10 CRT/Yoke Assemblies CRT/Yoke Assemblies Main FunctionCRT/Yoke Assemblies Inputs CRT/Yoke Assemblies Output CRT/Yoke Assemblies Service Adjustments CRT/Yoke Assemblies Operation Electronics Electronics Electronics 30View of CRTs, Relay lenses and ILA Assemblies CRT/Yoke Assemblies Remove and Replace Video Input Cards VICs Standard Rgbhv VIC Rgbhv VIC Main Functions Rgbhv VIC Service Adjustments Rgbhv VIC InputsRgbhv VIC Outputs Rgbhv VIC Operation Graphics Enhancer Plus Rgbhv VIC Grahics Enhancer Plus Rgbhv VIC Main Functions Graphics Enhancer Plus VIC Inputs Graphics Enhancer Plus VIC Outputs Graphics Enhancer Plus VIC Operation Graphics Enhancer Plus VIC Service AdjustmentsGraphics Enhancer Plus VIC Remove and Replace Input Quad Rgbhv VIC Main Functions Input Quad Rgbhv VICInput Quad Rgbhv VIC Inputs 364-Input Quad Rgbhv VIC Input Quad Rgbhv VIC Service Adjustments Input Quad Rgbhv VIC OutputsInput Quad Rgbhv VIC Operation Input Quad Rgbhv VIC Remove and Replace YPbPr VIC YPbPr VIC Main Functions YPbPr VIC Outputs YPbPr VIC InputsYPbPr VIC Operation YPbPr VIC Service Adjustments YPbPr VIC Remove and Replace Quad Standard Decoder VIC Quad Standard Decoder VIC Main Functions Quad Standard Decoder VIC Outputs Quad Standard Decoder VIC InputsQuad Standard Decoder VIC Operation Quad Standard Decoder/Line Doubler VIC Quad Standard Decoder VIC Service AdjustmentsQuad Standard Decoder VIC Remove and Replace Electronics 42Backplane Diagram left side Backplane PCB See Figure 44Backplane Diagram right side Electronics Miscellaneous Items Projector Covers Electronics Module Tilt-up Ventilation 1Electronics Module hinge and locking mechanism IR Detectors Air FiltersEMI Filter Cleaning Lenses, ILA Assemblies and Mirrors Miscellaneous Items Troubleshooting LEDs Backpanel LEDs Troubleshooting Troubleshooting Video Processor PCB LEDs Video Processor Test Points Video Processor LEDs Raster Timing Generator PCB LEDs 6Raster Timing Generator LEDs Raster Timing Generator PCB LEDs Convergence Deflection PCB LED Video Amplifier PCB LED Backplane PCB LEDs Diagrams Command on Timing Troubleshooting Image Path Deflection Path Troubleshooting Troubleshooting 14CRT Deflection path between the Scan Reversal PCB and CRT CRT Protection Troubleshooting 16CRT Protection path between the Scan Reversal PCB and CRT Error Codes IIC Handler Troubleshooting Troubleshooting Troubleshooting Guide Problem Check Possible Solution Section Troubleshooting on the Backplane PCB 17Backplane Diagram left side Lamplit Lampok Lampena Coveron GND 19Backplane Diagram right side Troubleshooting Software and Protocol Software Updating Command Software and Protocol Updating Configuration Importing/Exporting Exporting Windows Terminal Transfers + Receive Text File Similar message is displayed on the projector screen Importing Stop, Pause, % complete bar, Sending EXPORT1.TXT Data Transfer Error Example Model 250 Menu will display Null Modem Adapter Terminals Terminals and Communication ProtocolsTerminal Preferences Communications Protocol POS RGB Software and Protocol Software and Protocol Replacement Parts List Description Description Spares Description Quantity Parts List Cross-member Assembly AmorphousArc Lamp Aspect Ratio Laser Power Supply FieldFrame Horizontal Scan Resolution LumenLuminance Noise Vertical Resolution VideoSaturated Color Scan Vertical Scan Frequency Vertical ScanVertical Synchronization Frequency