Vertical Linearity Tracking | JVC 330, 370 SC, 340 SC instruction

Chapter 3---Service Adjustments

Blue

Vertical

Linearity

Blue	Red	Green	Green	Red
Vertical	Vertical	Vertical	Vertical	Vertical
Size	Linearity	Linearity	Size	Size



		R			R				R				R		R				R				R				R		R		R
328			411			311							211		36		228			428						96		139 171

CAUTION!!!

Do not adjust the pots that are shaded! They are factory adjusted. Do not adjust the Green Vertical Size or Green Vertical Linearity unless the Green Yoke or Green CRT has been replaced.

Figure 3-3Vertical Size and Linearity Controls on the Vertical Deflection Board.

3.4 Vertical Linearity Tracking

If the vertical linearity is not completely linear, use a small slot screwdriver and adjust the vertical linearity controls on the Vertical Deflection Board (refer to Figure 3-2).

NOTE: The Vertical Linearity pots are factory adjusted and will not normally need adjustment. The Green Vertical Linearity pot (R-211) in particular, should not need to be adjusted unless the Green Yoke or Green CRT has been replaced. If the Green Vertical Linearity is off, however, it should be adjusted.

To adjust vertical linearity:

1.Select Test Pattern 2.

2.Remove the projector cover.

3.Remove the electronics module cover.

4.View Red over Green and position Red (use the POS control and the arrow keys on the remote) so that the Red lines at the edge match the Green lines.

5.Adjust the Red Vertical Linearity pot R-411 so that Red linearity matches Green.

6.Repeat the same procedure for Blue (R-311).

7.Replace the electronics module cover and the projector cover.

3-6	Model 330, 340SC, 370SC Service Manual

Image 96

JVC 330, 370 SC, 340 SC service manual Vertical Linearity Tracking

Contents

Model Model 340 SC Model 370 SC Hughes-JVC Technology Corporation Manufacturer Hughes-JVC Technology Corporation Confidential and proprietary information Safety Equipment Introduction Installation Safeguards Projector Weight Heat Safeguards Light SafeguardsFans Ultra Violet and Infrared Light Viii Fluid Safeguards Power SupplyVentilation and Foreign Object Retrieval Safety Safety Acronyms Used In Manual Safety UpdatesHardware Compatibility Software Graphics enhancement Memories Decoder board option Contents Functional Descriptions 1Model 330, 340SC and 370SC System Block Diagrams Cover and Base External Power Requirements Electronics Systems Overview Functional Descriptions System Power System Power Supply STB STB AC Input CRT SCB HDB VDB VPB RTG VAB 4System Power Supply Input/Output Diagram Arc Lamp Ignitor 22-30V depending on projector model High Voltage Power Supply High Voltage Power Supply Functional Descriptions Card Cage Circuit Boards 104668 Backplane Board 100571 Functional Descriptions 10Raster Generation Block Diagram 11Raster Timing Generator Block Diagram Raster Timing Generator Board RTG p/n Sync Generator Sync Detector and Selector Phase Locked Loop Serration and Equalization LockoutVsync Detector, Field Separator, and Mux Adjustment Counters Serial Communication Information Description Raster Timing Generator I/O System Controller BoardInputs Description Outputs Description Video Processor Board Vertical Deflection Board Interlocks and Protection Horizontal Deflection Board P/N 102523 HDB 12Horizontal Deflection Board Block Diagram Vertical Oscillator Horizontal Phase Locked Loop Horizontal Power SupplyHorizontal Centering Flyback Switching Geometric CorrectionOutput Section Horizontal Sweep Failure Detection Bus Information DescriptionIIC Horizontal Deflection Board I/O Raster Timing Generator Inputs Description Vertical Deflection Board Inputs DescriptionMain Horizontal Deflection Coils Inputs Description Vertical Deflection Board P/N 102521VDB GND Functional Description Vertical Preamps 13Vertical Deflection Board Vertical Amplifiers Sweep Failure DetectionSide Pincushion and Keystone Correction Horizontal Linearity Correction Top and Bottom Pincushion and Keystone Correction Correction Amplifiers Rxcorr Rycorr Gxcorr Gycorr Bxcorr General I/O Input Description System Controller Board Output Description Video Processor Board Outputs DescriptionHorizontal Deflection Board Inputs Description System Power Supplies Main Vertical Deflection CoilsCorrection Coils Interlocks and Shutdowns Functional Descriptions Video Processor Board P/N 104672 VPB 15Video Processor Board, Block Diagram Decoder Video/Sync Mux Sync StripSG Sync Strip R Brightness and Contrast Amplifiers On-Screen Switch Switch Logic and Video EnableGamma Correction RGB Sensitivity and Threshold Amplifier ILA Bias Dynamic Focus Amplifier IIC Vidok IIC SweepokIIC Beamdet Redbias Rthresh GthreshBthresh Raster Timing Generator Video Amplifier Board Inputs Description Video Amplifier Board Outputs DescriptionExternal Video Inputs Description Image Light Amplifiers Decoder High Voltage Power Supply Outputs Description System Power Supply Inputs DescriptionVdfocus Hdfocus Video Amplifier Board P/N 103567 or 103774 VAB Video Signal Failure Detection DC Restore Enable CircuitBeam Current Sense Arc Protection General I/O High Voltage Power Supply CRTsOutput Description System Controller Board P/N 104668 SCB General Functional Description CPU Working and Compressed Memory Expanded Memory Correction Address Generator DACs Overlay Memory Overlay Address Generator Overlay Interface LED Display Buffers and LogicRS232 Interface IR Interface IIC Interface Serial Interface Video Processor Board Description Video Processor Board Output Description Corrstrt Vertical Deflection Board Description Horizontal Deflection Board Dot Matrix Status Display RS-232 Interface Signals Backplane Board p/nIR Interface CRT Assembly Image Light Amplifier ILA AssemblyOptical Section Relay Lens Functional Description CRT Image Focuses ILAGenerates high intensity light beam Filters infrared light Arc Lamp Assembly PrismProjection Lens Image Light Amplifier Optical SubassembliesCold Mirror Ultraviolet Filter and Condensing Lens Functional Description Functional Descriptions Service Adjustments Service Cover-Off Power-On Sequence 1Power Interlock Switch and Main Circuit Breaker CRT Yoke Rotation Service Adjustments Vertical Size Tracking Vertical Linearity Tracking Horizontal Size Tracking ILA Bias Settings CRT Mechanical Focus Service Adjustments Service Adjustments Electronic Focus Jumper Settings Front/Rear Jumpers A R Inverted Vertical Jumpers 10 G2 Adjustment G2 SettingSensitivity/Threshold Offset Service Adjustments Arc Lamp Alignment and Focus Model 330 Arc Lamp Alignment and Focus Service Adjustments Model 340SC and 370SC Arc Lamp Alignment and Focus Axis Plate Arc Lamp Current Adjustment Model 340SC and 370SC Arc Lamp Adjustments Watts ± 25W Amps Normal Amps Maximum Service Adjustments Maintenance Remove/Replace Before performing any removal and replacement procedures 1Major components of the Model 330 Projector 2Major components of the Model 340SC and 370SC Projectors Projector Covers Ventilation Filters Arc Lamp Assembly Model 330 Ignitor and Arc Lamp Assembly P/N 900611S Removal J503 J504 Ignitor Assembly POS InputNEG Output Interlock Switch Fan Connector Circuit Breaker Collimating Condensing Lens Adjustment Mm Set Screw Mounting Screws System Power Supply To remove the system power supply see -4and -5and Figure Maintenance System and HV Power Supply left side of projector Electronics Module Maintenance Cathode Ray Tube CRT Model 330 CRT Removal Maintenance 10Model 340SC and 370SC CRT Assembly Video Amplifier Board VAB Model 340SC and 370SC CRT Removal CRT Yoke To remove the CRT yoke see -9or Figure High Voltage Power Supply Hvps Card Cage Printed Circuit Boards Image Light Amplifier Assembly Projection Lens 2for reference to part numbers, if necessary SCB Socket Battery Replacement 13System Controller Board Sram Chips Location Recommended Spares Description Quantity 330 340SC 370SC Troubleshooting General Information On-Screen Text Description Power-On Codes First Set Second Set Code Description Break Points Code Meaning Description Resetting the Projector Break Trap Data from the Diagnostics Menu Main Menu Structure Main Menu Problem Possible Solution Service Operator Symptom to Manual Cutoff Check Raster Edge Video image not Correct using P Incushion Squared Adjust Contrast and Brightness No response Set I/R remote dip switch settings Problem Possible Solution Service Operator Symptom to Manual Glossary of Terms CRT Hdtv ISO MTS VHS Secam Freq Vertical Glossary