Horizontal Vertical Deflection PCB Service Adjustments | JVC 250

Chapter 5---Electronics

the V_PARAB waveform. The output waveform V_RGB+ goes to the Scan Reversal PCB and then drives the Vertical Deflection Yokes. The Vertical Deflection Yoke return signal to the Horizontal Vertical Deflection PCB is V_RGB-.

Horizontal Vertical Deflection PCB - Service Adjustments

Vertical Size Adjustment

Tools Needed

Miniature Potentiometer-Trimmer Adjustment tool

To adjust the Vertical height (see Figure 5-15):

1.Remove the rear cover and pull the Interlock switch out to the Service Mode position.

2.Power ON the projector by IR Remote or PC, and allow it to stabilize for a minimum of 15 minutes

3.Use the X-hatch test pattern.

NOTE: The green image is the reference to which the red image and blue image will be matched. The green height pot should not need adjustment except when the green CRT has been replaced.

4.Hide Blue and view Red and Green.

5.If Red is higher than Green at the top and lower than Green at the bottom of the X-hatch image, or If lower than Green at the top and higher at the bottom, adjust Red vertical pot (R137) to correct the error.

Vertical Adjustment Potentiometers (see Figure 5-15) Red - R137

Green - R148 Blue - R160

Figure 5-16Red image needs vertical adjustment (decrease).

5-26	Model 250 Service Manual

Image 81

JVC 250 Horizontal Vertical Deflection PCB Service Adjustments, 16Red image needs vertical adjustment decrease

Contents

Model 250 Projector Manufacturer Hughes JVC Declaration of Conformity Table of Contents Troubleshooting Software and ProtocolParts Safety Contents Updates Acronyms Used Secam Introduction Contents Incoming Power Circuit Power SuppliesElectrical Section Optical Section Igniter AssemblyArc Lamp Module Optical Path CRTs ILA s Image Light Amplifier Relay Lens Assemblies Electronic SectionFront Projection Lens Input Cards VICs Printed Circuit Boards PCB Miscellaneous Items EMI Shield System Description Electrical Safety AC Power Cord Incoming Power CircuitAC Circuit Breaker AC EMI Filter Low Voltage Power Supply Lvps Power SuppliesLvps Main Functions Lvps Inputs Lvps Operation 1Low Voltage Power Supply I/O Diagram Lvps Service Adjustments Arc Lamp Power Supply AlpsLvps Remove and Replace Alps Main Functions Alps Outputs Alps Inputs Alps Operation 2Arc Lamp Power Supply signals and voltages Alps Remove and Replace Alps Service Adjustments Hvps Main Functions High Voltage Power Supply Hvps Hvps Outputs Hvps Inputs Hvps Operation Hvps Service Adjustments Hvps Remove and Replace 5High Voltage Power Supply cover PIN # Electrical Igniter Assembly Inputs Igniter AssemblyIgniter Assembly Outputs Igniter Assembly Operation Igniter Assembly Remove and Replace Igniter Assembly Service Adjustments Electrical Optical Arc Lamp Arc Lamp Service AdjustmentsArc Lamp Main Functions Arc Lamp Inputs Optical 2Arc Lamp alignment fixture Arc Lamp Remove and Replace 3Arc Lamp Assembly access door Optical Optical Path Main Function Optical Path Optical Path Inputs Optical Path OutputsOptical Path Operation Optical 6Optical Path 7Optical Path Optical Path Service Adjustments 8XY Positioner adjust holes ILA Main functions ILAILA Inputs ILA Outputs ILA Operation ILA Service Adjustments Optical Optical Optical Optical ILA Remove and Replace Projection Lens Relay Lenses Optical Optical Electronics 1Model 250 System Block Diagram System Controller PCB Main Function System Controller PCB Electronics Electronics System Controller PCB Inputs 5System Controller PCB I/O Diagram for other PCBs System Controller PCB Outputs System Controller PCB Operation Electronics System Controller PCB Remove and Replace Video Processor PCB Video Processor PCB Main FunctionsVideo Processor PCB Inputs 7Video Processor PCB I/O diagram for VICs and Power Supplies Video Processor PCB Outputs 8Video Processor PCB I/O diagram for PCBs Video Processor PCB Operation Video Processor PCB Remove and Replace 9Video Processor PCB LEDs Raster Timing Generator PCB Main Functions Raster Timing Generator PCB Raster Timing Generator PCB Inputs 11Raster Timing Generator for other PCBs Raster Timing Generator PCB Outputs Raster Timing Generator PCB Operation Raster Timing Generator PCB Remove and Replace 12LEDs on the Raster Timing Generator PCB Horizontal Vertical Deflection PCB Horizontal Vertical Deflection PCB Main FunctionsHorizontal Vertical Deflection PCB Inputs 13Horizontal/Vertical I/O Diagram Electronics Horizontal Vertical Deflection PCB Outputs Horizontal Vertical Deflection PCB Operation 16Red image needs vertical adjustment decrease Horizontal Vertical Deflection PCB Service Adjustments Electronics Convergence Deflection PCB Horizontal Vertical Deflection PCB Remove and ReplaceConvergence Deflection PCB Main Functions Convergence Deflection PCB Outputs Convergence Deflection PCB Inputs 19Convergence Deflection PCB I/O Diagram 20Convergence Deflection PCB I/O Diagram Convergence Deflection PCB Operation 21Physical layout of the Convergence/Deflection PCB Convergence Deflection PCB Remove and Replace Scan Reversal PCB Scan Reversal PCB Main FunctionsScan Reversal PCB Inputs Scan Reversal PCB Outputs 22Scan Reversal PCB I/O Diagram Electronics Scan Reversal PCB Operation 24Scan Reversal PCB I/O Diagram for CRT Yokes Electronics Scan Reversal PCB Service Adjustments Electronics 1Projection orientation jumper settings Video Amplifier PCB Scan Reversal PCB Remove and ReplaceVideo 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 CRT/Yoke Assemblies Main Function 10 CRT/Yoke AssembliesCRT/Yoke Assemblies Inputs CRT/Yoke Assemblies Output CRT/Yoke Assemblies Operation CRT/Yoke Assemblies Service Adjustments Electronics Electronics Electronics 30View of CRTs, Relay lenses and ILA Assemblies CRT/Yoke Assemblies Remove and Replace Video Input Cards VICs Rgbhv VIC Main Functions Standard Rgbhv VIC Rgbhv VIC Inputs Rgbhv VIC Service AdjustmentsRgbhv VIC Outputs Rgbhv VIC Operation Grahics Enhancer Plus Rgbhv VIC Main Functions Graphics Enhancer Plus Rgbhv VIC Graphics Enhancer Plus VIC Outputs Graphics Enhancer Plus VIC Inputs Graphics Enhancer Plus VIC Service Adjustments Graphics Enhancer Plus VIC OperationGraphics Enhancer Plus VIC Remove and Replace Input Quad Rgbhv VIC Input Quad Rgbhv VIC Main FunctionsInput Quad Rgbhv VIC Inputs 364-Input Quad Rgbhv VIC Input Quad Rgbhv VIC Outputs Input Quad Rgbhv VIC Service AdjustmentsInput Quad Rgbhv VIC Operation Input Quad Rgbhv VIC Remove and Replace YPbPr VIC Main Functions YPbPr VIC YPbPr VIC Inputs YPbPr VIC OutputsYPbPr VIC Operation YPbPr VIC Remove and Replace YPbPr VIC Service Adjustments Quad Standard Decoder VIC Main Functions Quad Standard Decoder VIC Quad Standard Decoder VIC Inputs Quad Standard Decoder VIC OutputsQuad Standard Decoder VIC Operation Quad Standard Decoder VIC Service Adjustments Quad Standard Decoder/Line Doubler VICQuad Standard Decoder VIC Remove and Replace Electronics Backplane PCB 42Backplane Diagram left side See Figure 44Backplane Diagram right side Electronics Projector Covers Miscellaneous Items Electronics Module Tilt-up 1Electronics Module hinge and locking mechanism Ventilation Air Filters IR DetectorsEMI Filter Cleaning Lenses, ILA Assemblies and Mirrors Miscellaneous Items Troubleshooting Backpanel LEDs LEDs Troubleshooting Troubleshooting Video Processor Test Points Video Processor PCB LEDs Video Processor LEDs 6Raster Timing Generator LEDs Raster Timing Generator PCB LEDs Raster Timing Generator PCB LEDs Convergence Deflection PCB LED Video Amplifier PCB LED Backplane PCB LEDs Command on Timing Diagrams 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 IIC Handler Error Codes Troubleshooting Troubleshooting Problem Check Possible Solution Section Troubleshooting Guide 17Backplane Diagram left side Troubleshooting on the Backplane PCB Lamplit Lampok Lampena Coveron GND 19Backplane Diagram right side Troubleshooting Software Updating Software and Protocol Command Software and Protocol Updating Importing/Exporting Configuration Windows Terminal Transfers + Receive Text File Exporting Importing Similar message is displayed on the projector screen Stop, Pause, % complete bar, Sending EXPORT1.TXT Null Modem Adapter Data Transfer Error Example Model 250 Menu will display Terminals and Communication Protocols TerminalsTerminal Preferences Communications Protocol POS RGB Software and Protocol Software and Protocol Description Replacement Parts List Description Description Quantity Spares Parts List Amorphous Cross-member AssemblyArc Lamp Aspect Ratio Field Laser Power SupplyFrame Horizontal Scan Lumen ResolutionLuminance Noise Video Vertical ResolutionSaturated Color Scan Vertical Scan Vertical Scan FrequencyVertical Synchronization Frequency