JVC 250 Service Manual Download Page 99

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Chapter 5---Electronics

5-44

Model 250 Service Manual

Video Amplifier PCB - Inputs

RGB_VIDEO - image pre-amp signals from the Video Processor PCB (about 0.5
Vpp).

RESTORE - image DC restorations pulse from Video Processor PCB, logic level
positive going 4% duty cycle.

BLANKING - Blanking signal, logic F type.

_SUPPLY - supply for G

grid on CRTs from High Voltage Power Supply

(about -150 V).

_BIAS - brightness control line from Video Processor PCB (0-5 VDC).

RGB_G

- G

(black level) control lines from Video Processor PCB (0-3.1 V).

_SUPPLY - supply for G

grid on CRTs from High Voltage Power Supply

(about 1200 V).

RGB_ FOCUS - Focus supply for CRTs from the High Voltage Power Supply
(approximately 7 kV).

SWEEP_OK - deflection status line from the Horizontal Vertical Deflection PCB.

+80 V - from the Low Voltage Power Supply

±15 V - input power for the analog circuitry from the Low Voltage Power Supply.

6.2 V - input power for the CRT filaments heaters from the Low Voltage Power
Supply.

Summary of Contents for 250

Page 1: ...SERVICE MANUAL Model 250 Projector Phone 760 929 5300 Fax 760 929 5410 2310 Camino Vida Roble Carlsbad California 92009 ...

Page 2: ...2 1 1992 IEC 801 4 1988 ANSI C63 4 1992 FCC Part 15 Class A In addition the above product complies with the requirements of the Low Voltage Directive 73 23 EEC and the EMC Directive 89 336 EEC 106784 First Edition May 1999 Copyright 1999 by Hughes JVC Technology Corporation All worldwide rights reserved This manual was produced by Hughes JVC Technology Corporation and may be revised without prior ...

Page 3: ...ssembly 15 Chapter 4 Optical 4 1 Arc Lamp 4 2 4 2 Optical Path 4 7 4 3 ILA 4 12 4 4 Relay Lenses 4 19 4 5 Projection Lens 4 19 Chapter 5 Electronic 5 1 Safety 5 1 5 2 Introduction 5 2 5 3 System Controller PCB 5 3 5 4 Video Processor PCB 5 11 5 5 Raster Timing Generator PCB 5 16 5 6 Horizontal Vertical Deflection PCB 5 21 5 7 Convergence Deflection PCB 5 28 5 8 Scan Reversal PCB 5 34 5 9 Video Amp...

Page 4: ...roubleshooting 7 1 Safety 7 1 7 2 LEDs 7 2 7 3 Diagrams 7 12 7 4 Error Codes 7 22 7 5 Troubleshooting Guide 7 25 Chapter 8 Software and Protocol 8 1 Software Updating 8 1 8 2 Importing Exporting 8 5 8 3 Terminals and Communication Protocol 8 10 Chapter 9 Parts 9 1 Replacement Parts List 9 1 9 2 Recommended Spares 9 3 Glossary A 1 ...

Page 5: ...nfiguration of major and minor components This manual will assist the Hughes JVC Certified Technician with information to properly maintain and when necessary troubleshoot the Model 250 projector Use the Model 250 Service Manual in conjunction with the Model 250 User s Guide The User s Guide covers Installation Operation Setup Adjustments Specifications This Service Manual covers Projector functio...

Page 6: ...sing Unit CRT Cathode Ray Tube EMI Electromagnetic Interference EPROM Erasable Programmable Read Only Memory FPGA Field Programmable Gate Array F to V Frequency to Voltage G1 CRT Grid 1 G2 CRT Grid 2 HVDB Horizontal Vertical Deflection Board Hz Hertz HSYNC Horizontal Sync HVDB Horizontal Vertical Deflection Board HVPS High Voltage Power Supply IIC Inter Integrated Circuit ILA Image Light Amplifier...

Page 7: ...th memory SRB Scan Reversal Board SYNC Synchronization TTL Transistor Transistor Logic UL Underwriter Laboratories UV Ultraviolet VAB Video Amplifier Board VCO Voltage Controlled Oscillator VIC Video Input Card VIN Video Input VPB Video Processor Board VSYNC Vertical Sync VTR Video Tape Recorder Y Luminance ...

Page 8: ...e Assemblies 2 7 2 5 Miscellaneous Items 2 7 Projector Covers 2 7 IR Detectors 2 7 Cooling Fans 2 7 Air Filters 2 7 EMI Shield 2 8 2 1 Introduction This chapter is divided into four basic sections the Electrical Section the Optical Section the Electronic Section and the Miscellaneous Items Each section gives a basic description of the components in the section and a description of the function of ...

Page 9: ...nnects and disconnects the projector from electrical energy and protects the projector from over voltage conditions AC Line Filter The AC SF Series Line Filter reduces radiation generated by a regulated power supply from returning to the AC power source Power Supplies Low Voltage Power Supply LVPS The LVPS supplies standby voltages and the main system voltages to the projector Arc Lamp Power Suppl...

Page 10: ...ntensity light for the Model 250 Its output is rated at 2 kW The Arc Lamp has an expected 50 lifetime half of initial light output of 1000 hours Optical Path The Optical Path consists of all the optical components that transmit filter separate bend or straighten the Arc Lamp light The Optical Path also includes Polarizing Prisms Prepolarizing Prisms Steering Prisms and the 4P Combining Prism that ...

Page 11: ... Steering Prisms When the polarized light leaves the Prism Assembly and enters the ILA the light is modulated by the ILA The modulated light reflects off the ILA mirror and returns to the Prism Assembly Inside the Prism Assembly the light for the red and blue reflect off the two Steering Mirrors one for red one for blue and enter the 4P Combining Optic 4P Combining Optic The 4P Combining Optic tak...

Page 12: ...oards PCBs and the CRT Yoke assemblies Input Cards VICs There are two standard Input Cards and four optional VICs The Input Cards are the first stop for the source input signal They provide the RGB and Sync interface for the projector All VICs are IIC controlled Standard VICs Standard RGBHV VIC The RGBHV VIC is a straight feed through with an IIC selection control Graphic Enhancer Plus VIC The Gra...

Page 13: ...tical Deflection PCB The Horizontal Vertical Deflection PCB supplies the deflection waveforms that drive the deflection yokes on the CRTs for the horizontal and vertical raster It integrates the geometry correction such as pincushion keystone and vertical linearity onto the horizontal deflection waveform and adjusts the horizontal and vertical center raster Convergence Deflection PCB The Convergen...

Page 14: ...rear cover Both covers can be tilted up and or removed to service the projector The covers should not be opened while the projector is operating without proper safety protection review the Safety Chapter IR Detectors The Model 250 can be controlled by a handheld IR Remote Control The IR Infrared Detectors receive infrared pulses from these remote controls and use them to control various functions ...

Page 15: ...odel 250 has an EMI Electro Magnetic Interference Shield that traps and collects high frequency noise that is radiated by switching power supplies such as the Arc Lamp Power Supply and the Low Voltage Power Supply This high frequency noise can interfere with the operation of radios televisions and other electronic devices Figure 2 2 Relative location of CRTs Relay Lenses ILA s and Air Filters ...

Page 16: ...Chapter 2 System Description Model 250 Service Manual 2 9 ...

Page 17: ...ING When performing procedures in this chapter that require projector covers to be off wear high voltage gloves ANSI ASTM 10 000 volt rated when working near the CRTs Arc Lamp or power supplies Wear safety goggles rated X5 when working anywhere near the light path from the arc lamp or the projection lens CAUTION It is very strongly recommended that setup data be downloaded Exported see section 8 2...

Page 18: ...energy will reach any part of the projector except for the AC Circuit Breaker When the AC Circuit Breaker is in the ON position electrical energy goes to the AC Line Filter and on to the Low Voltage Power Supply and Arc Lamp Power Supply When the AC Circuit Breaker is in the ON position but the projector has not received the POWER ON command either from an IR Remote Control or from a PC or Laptop ...

Page 19: ...ut the AC Circuit Breaker is in the ON position Provides power 24 V for all cooling fans LVPS Inputs The Low Voltage Power Supply receives AC input power directly from the AC Line Filter The input range is from 220 VAC to 240 VAC at 50 60 Hz LV_ENA from the System Controller PCB This signal enables the LVPS when the System Controller receives a Power On command FAN_ENA from the System Controller P...

Page 20: ... LVPS to turn on the 24V Standby power for the cooling fans If the System Controller PCB does not receive a POWER ON command from an IR remote control or a PC it waits about 10 minutes and then tells the LVPS FAN_ENA goes high to shut off 24V Standby power This shuts off the cooling fans More importantly after the System Controller PCB receives a POWER OFF command it waits 10 minutes and then tell...

Page 21: ...Projector Covers section 6 1 4 Remove the lower right side panel by removing the 5 Pozi drive screws securing it 5 Remove the 5 Pozi drive screws securing the EMI Shield Slide the shield to the left and remove it 6 Remove J76 DC Output and J75 AC Input from the left side of the Low Voltage Power Supply NOTE These connectors may be a little difficult to remove and it may be necessary to pull the LV...

Page 22: ...t the Arc Lamp Power Supply tied to ground so it is always low Active Low ALPS Outputs 170 VDC output during the boost phase to get Arc Lamp ignition This supplies the power for the Igniter Run Voltage 25 to 31 V to maintain the arc lamp operation Current 70 to 85 amps to maintain the arc lamp operation LAMP_OUT Lamp output voltage positive LAMP_RTN Lamp return LAMP_LIT signal to System Controller...

Page 23: ...to the Arc Lamp Power Supply and activates the Arc Lamp Power Supply Once the Arc Lamp Power Supply receives the LAMP_ENA signal from the System Controller PCB it supplies the 170 VDC boost voltage to the primary coil of the Igniter The Laser Power Supply charges up a capacitor When the capacitor reaches 5 5 kV a spark gap arcs causing a very high voltage pulse approximately 32 kV to be induced on...

Page 24: ...tive output goes to the Anode of the Arc Lamp and is tied to chassis ground The Arc Lamp Power Supply is shielded electrically and magnetically to prevent noise or disturbances in the CRTs or other circuitry Figure 3 3 Arc Lamp Power Supply connections ALPS Service Adjustments The Arc Lamp Power Supply for the Model 250 is preset at the factory and does not have any Service Adjustments The output ...

Page 25: ...transient spikes from the Arc Lamp when it arcs Re attach the capacitor with the Arc Lamp output leads during reinstallation of new Arc Lamp Power Supply 9 Remove the 1 Pozi drive Phillips head screws from the bottom of the front of the Arc Lamp Power Supply The other screw was removed with the EMI Shield 10 Carefully slide the Arc Lamp Power Supply out of the projector 11 Replace the Arc Lamp Pow...

Page 26: ...o Amplifier PCB VA_OK H_PARABOLA The horizontal parabola from the Convergence Deflection PCB used by the Dynamic Focus Amplifier V_PARABOLA The vertical parabola from the Convergence Deflection PCB used by the Dynamic Focus Amplifier 15 V The power source for the analog circuitry in the High Voltage Power Supply 80 V The input power for the High Voltage section of the High Voltage Power Supply HVP...

Page 27: ...e Focus Pack divides the Focus Voltage into three signals and outputs each signal to a CRT The DC Focus Voltages are manually adjusted as necessary The Arc Ground signal goes to the Video Amplifier PCB and from there connects to the CRT It provides a direct return path for arc currents in the event of internal CRT arcing High Voltage and CRT Protection The High Voltage Power Supply receives a HV_E...

Page 28: ...1 Power off the projector by IR Remote or PC and allow the cooling fans to run until they shut off 2 Turn the AC Circuit Breaker to the OFF position and unplug the AC Power Cord 3 Remove the front cover 4 Remove the High Voltage Power Supply cover see Figure 3 5 by removing the 1 Pozi drive screw that secures the HVPS at the bottom of the cover and loosening the 2 Pozi drive screws at the top of t...

Page 29: ...H PARABOLA 14 H DRIVE HVPS_SYNC 7 GND DAF 8 80V Figure 3 6 High Voltage Power Supply 5 Carefully slide the cover upward and outward to remove it NOTE Refer to Figure 4 5 for the remainder of this procedure 6 Disconnect the three CRT Anode Cables 7 Disconnect P44 G2 Out at the middle front of the HVPS 8 Unsnap the cable clamp at the top of the HVPS 9 Remove the Anode Cables and the P44 cable from t...

Page 30: ... two Posi drive screws that hold the top of the HVPS metal housing to the projector frame 16 Grasp the HVPS at the bottom and lift upward and outward so that it slides away from the bottom screws 17 Reinstall the High Voltage Power Supply in the reverse order NOTE When reinstalling the High Voltage Power Supply Make sure it slides over the bottom screws and the lip at the top of the projector fram...

Page 31: ... operation Igniter Assembly Operation The Igniter has two functions to light the Arc Lamp and to act as a link between the Arc Lamp Power Supply and the Arc Lamp during normal Arc Lamp operation The Igniter contains the spark gap and the step up transformer that supplies the 32 kV pulse that lights the Arc Lamp During lighting of the Arc Lamp the Arc Lamp Power Supply receives the LAMP_ENA signal ...

Page 32: ...Pozi drive Phillips head screwdriver Parts Needed Igniter Assembly p n 106570 To remove the Igniter Assembly 1 Power the projector Off by IR Remote or PC and allow the cooling fans to run until they shut off 2 Turn the AC Circuit Breaker to the OFF position and unplug the AC Power Cord 3 Remove the front cover see Projector Covers section 6 1 4 Disconnect the white Anode cable from the output of t...

Page 33: ...n it It goes to the negative terminal of the Arc Lamp Power Supply 6 Disconnect the orange Cathode cable from the Igniter ground post using the 7 16 inch wrench Remove the other orange cable that goes to the positive terminal of the Arc Lamp Power Supply 7 Remove the five 1 Pozi drive Phillips head screws 8 Lift the Igniter Assembly out of projector 9 Reverse the procedure to install the Igniter A...

Page 34: ... anywhere near the light path from the arc lamp or the projection lens Dangerous levels of ultraviolet and infrared radiation dangerous glare very high temperatures 180 C to 300 C and high internal gas pressure are present at the Xenon Arc Lamp The lamp is contained in a protective reflector housing module and should not be operated outside this housing or outside of the projector When replacing t...

Page 35: ... Power Supply drops to a constant 25 31 volts at 70 85 amps It will stay at this level during normal Arc Lamp operation Arc Lamp Service Adjustments When a new Arc Lamp is installed it will need to be aligned using the Arc Lamp adjustment fixture located inside the Arc Lamp housing see Figure 4 2 Arc Lamp Adjustment Tools Needed Large Flatblade screwdriver 4 mm Hex head wrench Equipment Needed Min...

Page 36: ...en ILA bias value because Red and Blue will return to their original levels when Green is reset 8 Use the up arrow key and adjust the ILA bias for Green for maximum light output 9 Adjust the Arc Lamp alignment screws see Figure 4 2 to center the hot spot brightest area Figure 4 1 illustrates a hot spot on the screen NOTE It is easier to perform the following procedure with one person standing in f...

Page 37: ... Optical 4 4 Model 250 Service Manual Hot spot off center Figure 4 1 Arc Lamp Hot Spot brightest area is off center vertically and horizontally Adjust to center the hot spot Figure 4 2 Arc Lamp alignment fixture ...

Page 38: ...light and high current exist in this area of the projector Before proceeding with the removal of any subassemblies below verify that the circuit breaker at the rear of the projector is turned off and the power plug is removed from the AC outlet To Remove the Arc Lamp 1 Power off the projector by IR Remote or PC and allow the cooling fans to run until they shut off 2 Turn the AC Circuit Breaker to ...

Page 39: ...vides power to the Arc Lamp door fan through the white socket shown to the right of the Arc Lamp fan in Figure 4 3 Disconnect the cable at the socket connection below the Arc Lamp housing Disconnect the top fan cable 8 Disconnect large blower fan connector 9 Remove the FA shield from the top of the Arc Lamp Three 1 Pozi drive Phillips head screws hold the FA shield in place see Figure 4 4 10 Remov...

Page 40: ...ILA to the Projection Lens Removes the Infrared light that contains most of the heat Removes the unwanted Ultraviolet light Condenses the white light using the Light Pipe for a uniform output Separates the white light into its RGB component colors using Dichroic Beamsplitters Polarizes each of the component RGB light beams Combines the component RGB image beams into one beam and delivers that to t...

Page 41: ...he Arc Lamp into the Optical Path see Figure 4 5 The light reflects off a cold mirror and passes through a light pipe From the Light Pipe the light passes through a Condensing Lens The Condensing Lens also acts as a XY Positioner The function of the XY Positioner is to aim the light beam down the optical path and center it on the face of the ILA After being positioned by the Condensing Lens the li...

Page 42: ...s reflected by the Main Polarizer The reflected polarized light either red green or blue leaves the PBS and goes directly into the ILA see Figure 4 6 and Figure 4 7 Each color exits the Prism Assembly and enters an ILA where the Liquid Crystal in the ILA rotates the polarized light The image light striking the input side of the ILA modulates the polarized light The image on the input of the ILA or...

Page 43: ...Chapter 4 Optical 4 10 Model 250 Service Manual Figure 4 6 Optical Path ...

Page 44: ... 7 Optical Path Optical Path Service Adjustments Tools Needed 3 mm Hex wrench Parts Needed No serviceable parts The one adjustment that can be performed on the optical path is with the XY Positioner that moves the 1 Condensing Lens in the X and Y axis The XY ...

Page 45: ...allow it to stabilize for at least 15 minutes 2 Check the screen for dark edges on the top bottom left or right Check the screen with all three colors using the Variable Flat Field test pattern 4 or with ILA bias only The dark edge will be obvious in either mode 3 Remove the front cover 4 There are four access holes two with small notches on the top of the hole and two without notches see Figure 4...

Page 46: ...frequency ILA Sensitivity Adjustable offstate with Super Contrast ILA s Image light from CRT is blocked from output Image is electrostatically coupled to output ILA Inputs Arc Lamp light High intensity polarized Red Green or Blue light from the Prism Assembly Image light Red Green or Blue image light from the CRTs ILA Bias Voltage and Frequency 10 13 Vac at 2 kHz ILA Outputs Image light High inten...

Page 47: ...ough the menu see Model 250 User s Guide section 5 6 Setup Adjustments The ILA bias is individually adjustable for each ILA the ILA sensitivity frequency adjusts all the ILA s together Super Contrast ILA Compensator Adjustment The offstate level can be adjusted on Super Contrast ILA s The Compensator adjustment moves a lever on the top of each Super Contrast ILA to a null position The null positio...

Page 48: ...cked 4 Use the HIDE key to hide red green and blue 5 Increase the ILA bias for all three colors to maximum The image on the screen should be white with some colors at the edges 6 Check the right left top and bottom edges of the images on the screen Using the green image as a reference compare the edges of the red and blue image to the green image 7 NOTE If the green ILA has been replaced reference...

Page 49: ...ck 14 Loosen the two hex nuts using a 4 mm hex head wrench WARNING Always wear an ANSI ASTM 10 000 volt rated safety glove when working around CRTs due to the High Voltage present there 15 Slide the ILA Relay Lens CRT Assembly back and remove the ILA assembly it will slide out with some resistance 16 There are two adjustment screws at the bottom of the ILA assembly that move the ILA up or down Tur...

Page 50: ...orth This is a factory set adjustment but may need some touch up in the field Tools Needed 4 mm Hex wrench 2 5 mm Hex wrench Parts Needed No parts are needed To adjust the ILA Back Focus for a Zoom Lens 1 Power the projector ON and allow to stabilize for at least 15 minutes 2 Remove the Rear Cover and tilt up the Electronic Module 3 Hide Red and Blue View Green 4 Select the Focus Pattern Test Patt...

Page 51: ...pots while zooming up or down but they should be in focus at the smallest and largest images 13 Tighten the hex bolts on the Green ILA Assembly and the wing nut on the Green Relay Lens 14 Repeat Steps 9 13 for other colors that need ILA Back Focusing Be sure to hide the other two colors To adjust the ILA Back Focus for a Fixed Lens 1 Power the projector ON and allow it to stabilize for 15 minutes ...

Page 52: ...x wrench Parts Needed Super Contrast Blue 102630 14 Green 102630 15 Red 102630 16 NOTE Do not interchange Super Contrast ILA s The Compensators on the ILA s are color specific and can not be interchanged i e the green ILA can not be put in the red channel or blue channel To Remove the ILA 1 It is not necessary to power off the projector 2 Remove the Rear cover It is not necessary to tilt the Elect...

Page 53: ...here the red green and blue image light are combined The Projection Lens focuses this output image light onto the screen All Projection Lenses come with motorized focus adjustment The Model 250 projector comes with a choice of four standard lens options Motorized Zoom Lens 2 1 4 1 Fixed Lenses 0 96 1 1 5 1 5 6 1 Optional Lenses 2 4 1 Simulator Lens Projection Lens Service Adjustments There are no ...

Page 54: ... Holding Bolt needs to be loosened more to allow the Projection Sleeve to clear it 4 Rotate the Projection Lens left or right as needed so that the notch on the lens clears the holding screw on the lens holder see Figure 4 11 5 Carefully pull the Projection Lens out of the projector 6 Replace the Projection Lens in reverse order Be sure to reconnect the Zoom and Focus motor cables NOTE Use the sam...

Page 55: ...Chapter 5 Optical 3 4 22 Model 100 Service Manual ...

Page 56: ...hics Enhancer Plus VIC 5 61 4 Input Quad RGBHV VIC 5 64 YPbPr VIC 5 67 Quad Standard Decoder VIC 5 70 Quad Standard Decoder Line Doubler VIC 5 72 5 12 Backplane PCB 5 74 5 1 Safety CAUTION Before performing procedures in this chapter review the chapter on Safety at the beginning of this manual WARNING When performing procedures in this chapter that require projector covers to be removed wear high ...

Page 57: ...y convergence and shading see Chapter 4 of the User s Guide The Electronics System also controls video and sync input signals LED displays on PCBs at the rear and side of the projector two RS 232 communications ports and two IR receivers for remote control of the projector The descriptions in this portion of the manual are based on an overall Electronics System block diagram and simplified block d...

Page 58: ...excellent precautionary measure It will save the time of setting up new source file s in the case of an unexpected problem 5 3 System Controller PCB System Controller PCB Main Function Enables control for the Low Voltage Power Supply Arc Lamp and cooling fans Fault monitors the HVPS LVPS Arc Lamp and fans Provides IIC serial bus communication and control between PCBs Controls Zoom and Focus of the...

Page 59: ... or rear IR detectors External 3 color system status LEDs Green indicates normal yellow is standby and red indicates a fault condition External Service Mode Switch Pressing this switch during a power up sequence brings the system up in a diagnostic mode for maintenance rather than a normal operating mode Figure 5 3 Rear of Electronics Module with rear cover and panel removed ...

Page 60: ...Chapter 5 Electronics Model 250 Service Manual 5 5 Figure 5 4 System Controller PCB I O Diagram for Power Supplies and peripherals ...

Page 61: ...ing HV_OK signal from the High Voltage Power Supply it tells the System Controller PCB that all the high voltage supplies are working LAMP_OK signal from the Arc Lamp Power Supply LAMP_LIT signal from the Arc Lamp Power Supply it tells the System Controller PCB that the Arc Lamp is lit ODD_FIELD Square wave signal from the Raster Timing Generator PCB with 50 duty cycle that is low during odd field...

Page 62: ...tal frequency of the current source IIC CLK IIC clock line unidirectional clock line for control of synchronous data transfer of data between PCBs IIC DATA IIC data line bi directional serial data line for control of synchronous data transfer between the System Controller PCB and the Raster Timing Generator PCB 5 1 V Stdby from the Low Voltage Power Supply when the AC Circuit Breaker is turned on ...

Page 63: ...is powered ON the Low Voltage Power Supply sends 5 1 V stdby voltage to the System Controller PCB The 5 1 V Stdby powers the CPU and IR Detector so the System Controller PCB can receive and respond to the POWER ON command The System Controller PCB sends a FAN_ENA signal back to the LVPS turning on the 24 V Stdby to turn the cooling fans on When the System Controller PCB receives a POWER ON command...

Page 64: ...te Control are received through the RS 232 serial interface ports The two RS 232 ports labeled Terminal in and Control out are functionally almost identical Both ports can be used to interface with computers switchers or other remote controlling devices using a null modem cable The difference is importing and exporting of configuration data can only be performed through the Terminal in The dipswit...

Page 65: ...m the normal operating mode to a diagnostic mode If there is a new release of system software it can be uploaded into the projector by switching into the diagnostic mode The procedure for this is in the Software and Protocol section see Chapter 8 Software and Protocol System Controller PCB Remove and Replace Tools Needed 1 Pozi drive Phillips head screwdriver 0 Pozi drive Phillips head screwdriver...

Page 66: ...deo Processor PCB the timing and duration of the DC Restore BLANKING Pulse signal from the Raster Timing Generator PCB it tells the Video Processor PCB the blanking interval during the scan RGB_THRESH Threshold correction information for red green or blue from the System Controller PCB Real time data at 0 1 V RGB_SENS Sensitivity correction information for red green or blue from the System Control...

Page 67: ...Chapter 5 Electronics 5 12 Model 250 Service Manual Figure 5 7 Video Processor PCB I O diagram for VICs and Power Supplies ...

Page 68: ... signal to Video Amplifier PCB typically 0 1 V H V_SYNC horizontal sync pulse goes to the Raster Timing Generator PCB GRN_SYNC sync on green sync pulse goes to the Raster Timing Generator PCB RESTORE DC Restore control signal to the Video Amplifier PCB This signal controls the DC level of the image signal clamping it to the proper level on the Video Amplifier PCB ...

Page 69: ...ame Brightness shifts the DC level of the External image up or down while keeping the peak to peak amplitude the same The DC restore circuit or clamp pulse restores the DC offset black level after each horizontal line Contrast and Brightness commands come from the IIC data bus The DC Restore and Blanking signals come directly from the Raster Timing Generator PCB The Video Processor PCB switches in...

Page 70: ... the preset value the Video Processor PCB reduces the contrast for the CRT with high beam current If the CRT beam current is still high it then reduces the G2 voltage The maximum beam current is 250 µA per CRT The Video Processor PCB receives the G1_BIAS signal from the System Controller PCB through the IIC bus and sends a voltage to the Video Amplifier PCB to set the brightness level Figure 5 9 V...

Page 71: ...tions Generates an internal sync pulse Detects and selects sync pulses Generates a phase locked sync Generates blanking pulse Provides horizontal and vertical phase adjustments Detects interlaced and generates odd field pulse Selects horizontal frequency band Generates horizontal line count and vertical count Provides IIC interface Generates clamp pulse Detects changes in source Generates HVPS_SYN...

Page 72: ...Timing Generator PCB Inputs V_SYNC input vertical sync from the Video Processor PCB H_SYNC input horizontal sync from the Video Processor PCB G_SYNC Sync on Green sync stripped from green video signal at the Video Processor PCB ISYNC 5 MHz clock from the System Controller PCB used to generate the internal sync ...

Page 73: ...ized to the horizontal sync at 280 times the frequency of the horizontal sync This signal is used by the System Controller PCB to properly output shading and convergence data CLAMP a negative going image clamp signal to the Video Processor PCB with about 3 duty cycle BLANKING right left top and bottom blanking signal to the Video Processor PCB H_BAND 0 3 horizontal frequency band lines to the Hori...

Page 74: ...3 7 kHz horizontal and 60 Hz vertical The Raster Timing Generator PCB tells the System Controller PCB when there has been a source change using the SOURCE_VALID signal The Raster Timing Generator PCB generates the Blanking signal and the horizontal Phase signal Blanking shuts off the image during times where there is no active video The Blanking signal pulls the G1 voltage on the Video Amplifier P...

Page 75: ... 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 Disconnect all the external source video cables and control cables 4 Remove the rear cover 5 Remove the Back Panel Remove the nine Pozi drive Phillips head retaining screws using the 1 Pozi drive Phillips ...

Page 76: ... frequency bands from Raster Timing Generator PCB H_ENABLE from the Raster Timing Generator PCB enables the horizontal deflection supply Low enabled deflection High disabled deflection H_DRIVE square wave from the Raster Timing Generator PCB 50 duty cycle synchronized to the selected horizontal sync H_F2V a DC voltage from the Raster Timing Generator PCB proportional to horizontal frequency H_LOCK...

Page 77: ...K IIC clock line IIC_DATA IIC data line IIC_SINT IIC interrupt 15 V input power from the Low Voltage Power Supply for the analog circuitry 5 1 V input power from the Low Voltage Power Supply for the digital circuitry Figure 5 13 Horizontal Vertical I O Diagram ...

Page 78: ...Chapter 5 Electronics Model 250 Service Manual 5 23 Figure 5 14 Horizontal Vertical I O Diagram for Scan Reversal and Video Amplifier PCBs ...

Page 79: ...l deflection waveform return from the Scan Reversal PCB A DC offset that shifts the reference for red green and blue image for centering H_OUT_FLYB output waveform to the Scan Reversal PCB for the horizontal deflection coils on the CRTs H_LOCK pos 15 V to the Scan Reversal PCB for deflection yoke connector interlock V_RGB pos positive vertical deflection voltage to the Scan Reversal PCB V_RGB neg ...

Page 80: ...tal supply is H_OUT_SUPPLY that goes on to the Scan Reversal PCB CRT Protection The Horizontal Vertical Deflection PCB uses the H_LOCK H_LOCK and DEFL_OK signal to protect the CRTs from being damaged if the deflection waveforms are lost Refer to the CRT Protection section in Chapter 9 for a complete discussion of these and all the signals associated with CRT Protection The Horizontal Vertical Defl...

Page 81: ... 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 G...

Page 82: ...g adjustment see Model 250 User s Guide Chapter 5 Figure 5 18 Red image needs vertical centering If the Red height pot does not completely eliminate the difference in height between Red and Green balance the difference at the top and bottom Too much of an difference at the top or bottom makes convergence procedures harder to accomplish 4 Repeat Steps 2 and 3 above for Blue while hiding Red 5 Reche...

Page 83: ...tical Deflection PCB by sliding it toward the left side of the projector this is the upward direction if the electronic module is tilted up so that the mounting screws clear the access holes Then lift the side of the PCB that is nearest the front of the projector first and angle it upward so that the side closest to the rear clears the lip of the electronic module frame Be careful when removing or...

Page 84: ...nized to vertical sync with four horizontal line duty cycle WIDTH_CONTROL a DC waveform from the Horizontal Vertical Deflection PCB that controls the image width IIC_CLK IIC clock line IIC_DATA IIC data line IIC_SINT IIC interrupt line 15 V input power from the Low Voltage Power Supply for the analog circuitry 5 1 V input power from the Low Voltage Power Supply for the digital circuitry Convergenc...

Page 85: ...Chapter 5 Electronics 5 30 Model 250 Service Manual Figure 5 19 Convergence Deflection PCB I O Diagram ...

Page 86: ...Chapter 5 Electronics Model 250 Service Manual 5 31 Figure 5 20 Convergence Deflection PCB I O Diagram ...

Page 87: ...amplifier drives the CRT deflection coils for vertical deflection The Waveform Generator also generates the parabolic waveforms used for geometry correction such as bow pincushion keystone and linearity Each of the ILA s is biased by a square wave generated by the Waveform Generator on the Convergence Deflection PCB Each ILA is biased separately through the ILA Bias command in the Factory Adj Menu...

Page 88: ...on PCB p n 105210 To remove the Convergence Deflection PCB 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 the rear cover 4 Tilt the Electronic Module up 5 Disconnect six connectors J31 J32 J33 J38 J39 and J40 from the Convergence Deflection PCB s...

Page 89: ...flection waveform from the Horizontal Vertical Deflection PCB about 800 Vpp H_LOCK pos horizontal interlock for the yoke connectors from the Horizontal Vertical Deflection PCB about 5 V when closed 15 V when open H_RGB pos return of horizontal deflection waveform to the Horizontal Vertical Deflection PCB V_RGB pos output signals of red green and blue from the Vertical Amplifier of the Horizontal V...

Page 90: ... low ceiling high DEFL_OK deflection status line from the Horizontal Vertical Deflection PCB high about 2 V good low no scan X_RGB neg current feedback signals of the red green and blue Horizontal Convergence Amplifier for the x axis to the Convergence Deflection PCB Y_RGB neg current feedback signals of the red green and blue Horizontal Convergence Amplifier for the y axis to the Convergence Defl...

Page 91: ...Chapter 5 Electronics 5 36 Model 250 Service Manual Figure 5 22 Scan Reversal PCB I O Diagram ...

Page 92: ...Chapter 5 Electronics Model 250 Service Manual 5 37 Figure 5 23 Scan Reversal PCB I O Diagram for Horizontal Vertical Deflection PCB ...

Page 93: ... convergence and deflection yokes and it contributes significantly to the CRT Protection circuit The Scan Reversal PCB provides an interface for reversing the projection mode from front to rear projection and from upright to inverted upside down mounting projection setups The projection modes are changed by switching a jumper from one connector to another on the Scan Reversal PCB J100 and J101 are...

Page 94: ...ergence Yokes on the CRT without any further signal processing The Scan Reversal PCB provides for the adjustment of horizontal scan width Inductor L1 adjusts the red horizontal width and L5 adjusts the blue horizontal width L3 increases the horizontal size range of red and blue The Scan Reversal PCB contains two major components of the CRT Protection circuit The first component is the DEFL_OK sign...

Page 95: ... to stabilize for a minimum of 15 minutes 6 Use the X hatch test pattern 7 Hide Blue View Red and Green 8 If the Red image is outside the Green image on both sides or inside the Green image on both sides use a Delrin 100 hex alignment tool to adjust the Red horizontal size coil to correct the error If the Red image is outside the Green image on one side and inside of Green on the other side this i...

Page 96: ...tor is shipped with the jumper plugs inserted in J50 and J100 for front upright projection see Table 5 1 for other orientations To set the Horizontal Scan Jumper 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 the rear cover 4 Verify that the Hori...

Page 97: ... the vertical scan jumper will need to be changed to the inverted setting JA53 Figure 5 21 illustrates the location of the jumpers on the Scan Reversal Board The Model 250 Projector is shipped in the normal vertical projection position with the jumper plug inserted into J53 For an inverted vertical setup this jumper plug must be inserted into JA53 see Table 5 1 for other orientations To invert the...

Page 98: ... off automatically 2 Turn the AC Circuit Breaker to the OFF position and unplug the AC Power Cord 3 Remove the projector rear cover 4 Disconnect seven connectors seeFigure 5 25 J52 J54 J64 J65 J66 J50 or J50A and J100 or J101 To remove push in slightly squeeze the tabs and then pull connector out 5 Move all cables out of the way 6 Remove the four Pozi drive screws see Figure 5 25 and lift the boar...

Page 99: ...G1_BIAS brightness control line from Video Processor PCB 0 5 VDC RGB_G2 G2 black level control lines from Video Processor PCB 0 3 1 V G2_SUPPLY supply for G2 grid on CRTs from High Voltage Power Supply about 1200 V RGB_ FOCUS Focus supply for CRTs from the High Voltage Power Supply approximately 7 kV SWEEP_OK deflection status line from the Horizontal Vertical Deflection PCB 80 V from the Low Volt...

Page 100: ...Chapter 5 Electronics Model 250 Service Manual 5 45 Figure 5 26 Video Amplifier PCB I O Diagram ...

Page 101: ...CRTs Video Amplifier PCB Outputs RGB_BEAM Cathode beam current sense lines about 1 V per 100 µA RGB_CATHODE image output signal to CRTs about 40 Vpp with peak voltage of 70 V RGB_G1 G1 voltage to CRTs Blanking pulse to CRT RGB_G2 G2 voltage for CRTs about 600 800 V RGB_HEAT pos positive side of the CRT heater voltage about 6 2 V ...

Page 102: ...ltage Power Supply The G1 regulator regulates the 150 V G1 supply up to about 80 V The blanking pulse is added to the 80 V and the G1 bias adds an offset for brightness control This voltage is distributed to each of the CRT s G1 control grids G2 Black Level Voltage The Video Amplifier PCB receives the G2 supply voltage 1200 from the High Voltage Power Supply It receives the G2 control lines from t...

Page 103: ...s isolation of the anode voltage return through the Arc Ground circuit Occasionally particles flake off metal components inside CRTs that cause shorting inside the CRT On these occasions the Arc Ground circuit is an isolated ground path back to the High Voltage Power Supply This isolation protects the other supply voltage returns The Video Amplifier PCB has three CRT Socket PCBs that are attached ...

Page 104: ...e to any CRT connections 6 Carefully remove the Green CRT Yoke Assembly by sliding it backward and upward as far as possible before disconnecting the Green CRT Socket Connector from the CRT neck Use care to avoid bumping the CRT while removing it from the projector to avoid damaging it Also be careful not to pull any of the wires that connect from the CRT Socket Connector to the Video Amplifier to...

Page 105: ... is joined near the CRT by a coupler plug and jack Disconnect and label the focus cables at these couplers 13 Loosen the six Pozi drive Phillips head screws that secure the Video Amplifier PCB to the projector frame 14 Make sure everything is out of the way then slide the Video Amplifier PCB toward the left so the mounting screws will clear the access holes and remove the board from the projector ...

Page 106: ...age from High Voltage Power Supply 25 kV Focus Voltage from High Voltage Power Supply 7 kV RGB G1 G1 grid signal from Video Amplifier PCB RGB G2 G2 supply voltage from Video Amplifier PCB about 600 800 V RGB_CATHODE video output signal from the Video Amplifier PCB about 40 Vpp with a peak voltage of about 70 V RGB_HEAT pos positive side of CRTs heater voltage about 6 2 V CRT Yoke Assemblies Output...

Page 107: ...Yokes use magnetism to deflect the electron beam horizontally or vertically inside the CRT The Deflection Yokes deflect the electron beam at right angles so the Horizontal Deflection Yokes are on the top and bottom of the CRT The Vertical Deflection Yokes are on the left and right sides Both the horizontal and vertical deflection waveforms come from the Horizontal Vertical Deflection PCB Geometric...

Page 108: ...pattern test pattern 6 6 Zoom the Projection Lens to the widest angle largest image and adjust the Projection Lens focus for the sharpest image of the Focus test pattern 7 Loosen the two setscrews see Figure 5 29 near the top of the CRT sleeve using the 1 5 mm Hex head wrench 8 Loosen the CRT focus lock screw located on the Guide Plate at the top of the CRT shield see Figure 5 29 The CRT is now fr...

Page 109: ...stment and should not need adjusting unless the CRT or yoke is moved Tools Needed 1 5 mm Hex head wrench 0 Pozi drive Phillips head screwdriver 3 mm Hex head wrench To perform the CRT Rotation adjustment 1 Remove the rear cover 2 Power the projector ON and allow it to stabilize for at least 15 minutes 3 Tilt the electronic module to the full up position 4 Select Center Lin pattern test pattern 8 ...

Page 110: ...rench 9 Loosen the CRT Thumbscrew see Figure 5 29 on the top of the CRT Assembly using the 3 mm Hex head wrench if necessary NOTE The CRT Thumbscrew is used more as a handle to move the CRT position as in rotating the CRT or moving the CRT back and forth for Mechanical Focus When the positioning is complete only hand tighten the CRT Thumbscrew 10 Rotate the yoke by grasping the Thumbscrew and movi...

Page 111: ...cus adjustment 1 Remove the front and rear cover 2 Power the projector ON and allow it to stabilize for at least 15 minutes 3 Select the Focus pattern test pattern 6 4 Zoom the Projection Lens to the widest angle and adjust the Projection Lens focus for the sharpest image 5 View Green Hide Red and Blue 6 Adjust the Green Electronic Focus located on the side of the High Voltage Power Supply see Fig...

Page 112: ...t 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 Revers...

Page 113: ...ds the CRT Yoke Assembly firmly 12 After verifying that all cables are out of the way remove the CRT Yoke Assembly from the projector 13 Reinstall the CRT Yoke Assembly in the reverse order NOTE When reinstalling the CRT Yoke Assembly plug the CRT ground wire into the CRT Socket Connector first then partially plug the Green socket connector into the CRT Inserting the CRT fully into the socket conn...

Page 114: ...del 250 however the 4 Input RGBHV and the Quad Standard Decoder Line Doubler require two slots Standard RGBHV VIC RGBHV VIC Main Functions Interface for Red Green and Blue image inputs Interface for Horizontal and Vertical synchronization pulses IIC Serial Data Bus communication LED indication of VIC selection Figure 5 31 RGBHV VIC I O Diagram Figure 5 32 RGBHV VIC faceplate ...

Page 115: ...B V_VIC vertical sync to the Video Processor PCB SEL_VIC VIC select line to the Video Processor PCB RGBHV VIC Operation The RGBHV VIC receives the separate red green blue image inputs and horizontal and vertical sync inputs from the source input device and passes them directly through to the Video Processor PCB without any signal processing The VIC receives a SELECT command from the System Control...

Page 116: ...lue horizontal and vertical input BNC cables from the VIC 5 Remove the two retaining screws from the faceplate of the VIC 6 Pull the VIC out of the Electronics Module 7 Reverse the process to install the VIC Graphics Enhancer Plus RGBHV VIC Grahics Enhancer Plus RGBHV VIC Main Functions Interface for Red Green and Blue image inputs Interface for Horizontal and Vertical synchronization pulses IIC S...

Page 117: ... power for analog circuitry 15 V power for analog circuitry 5 1 V power for digital circuitry 5 1 V Stdby IIC CLK IIC clock line IIC DATA IIC data line IIC SINT IIC interrupt line Graphics Enhancer Plus VIC Outputs RED_VIC red image to the Video Processor PCB 0 7 1 0 Vpp GRN_VIC green image to the Video Processor PCB 0 7 1 0 Vpp BLU_VIC blue image to the Video Processor PCB 0 7 1 0 Vpp H_VIC horiz...

Page 118: ... PCB through the IIC data bus to activate the VIC The VIC sends a SEL_VIC signal to an internal Input Switcher Mux on the Video Processor PCB This tell the Video Processor PCB which VIC is selected An operator selects the VIC in the Channels Menu see section 4 6 in the User s Guide A green LED is illuminated when the VIC is selected Graphics Enhancer Plus VIC Service Adjustments There are no physi...

Page 119: ...C Serial Data Bus LED indication of VIC selection Figure 5 35 4 Input Quad RGBHV VIC faceplate two VIC slots 4 Input Quad RGBHV VIC Inputs Four sets of inputs R red image from source input 0 7 1 0 Vpp G green image from source input 0 7 1 0 Vpp B blue image from source input 0 7 1 0 Vpp H horizontal sync from source input V vertical sync from source input 15 V power for analog circuitry 15 V power...

Page 120: ...Chapter 5 Electronics Model 250 Service Manual 5 65 IIC CLK IIC clock line IIC DATA IIC data line IIC SINT IIC interrupt line Figure 5 36 4 Input Quad RGBHV VIC ...

Page 121: ...e Video Processor PCB which VIC is selected and which set of inputs is selected An operator selects the VIC and input in the Channels Menu see section 4 6 in the User s Guide A green LED illuminates when the VIC is selected The 4 Input Quad RGBHV VIC uses two VIC slots 4 Input Quad RGBHV VIC Service Adjustments There are no service adjustments on the RGBHV VIC 4 Input Quad RGBHV VIC Remove and Rep...

Page 122: ... The YPbPr PCB converts these component signals to RGB type image signals YPbPr VIC Main Functions Image input and output buffers Conversion of YPbPr signal format to RGB signals format Separation of syncs from the Y G input signal Hue sharpness gamma and color adjustment Selection of RGB component input or YPbPr input LED indication IIC serial bus interface Figure 5 37 YPbPr VIC I O Diagram ...

Page 123: ...1 V power for digital circuitry 5 1 V Stdby not used IIC CLK IIC clock line IIC DATA IIC data line IIC SINT IIC interrupt line YPbPr VIC Outputs RED_VIC red image to Video Processor PCB 0 7 1 0 Vpp GRN_VIC green image to signal Video Processor PCB 0 7 1 0 Vpp BLU_VIC blue image to Video Processor PCB 0 7 1 0 Vpp SYNC composite horizontal and vertical sync to Video Processor PCB SEL_VIC VIC select ...

Page 124: ...equency peaking of the black and white details These options are not available and are disabled in the RGB mode The YPbPr VIC has two LEDs The RGB LED illuminates green when the YPbPr_VIC is in RGB input mode The YPbPr LED illuminates green when the YPbPr_VIC is in YPbPr input mode Only one LED will be illuminated at one time Neither LED is illuminated when the YPbPr_VIC is not selected as the inp...

Page 125: ...der VIC converts Composite and S image formats to RGBHV format Quad Standard Decoder VIC Main Functions Select input source Composite or S video Select standard AUTO NTSC PAL SECAM 4 43NTSC Conversion of composite and S image signals to RGB image signals Separation of syncs from the input signal Tint sharpness and color adjustment LED indication of Composite or S video IIC serial bus interface Fig...

Page 126: ... Both the Composite and S image formats may be in a variety of different signal standards such as NTSC U S PAL European SECAM or 4 43 NTSC The VIC accepts all of these standards The Quad Standard Decoder VIC converts Composite and S image to the RGBHV format The selection of the VIC and inputs is controlled by the System Controller Board via the IIC serial bus interface An operator selects the VIC...

Page 127: ...r Line Doubler VIC The Quad Standard Decoder Line Doubler VIC is very similar in function to the Quad Standard Decoder VIC It accepts the same two source input formats Composite and S image and processes them exactly the same It has two LEDs that function exactly as the Quad Standard Decoder VIC The inputs outputs and signal processing are also the same Selecting the VIC is done in the Channels Me...

Page 128: ...ot a blank face plate must be installed above it The blank faceplate is not included with the Quad Standard Decoder Line Doubler VIC unless it is installed at the factory The part number for the blank faceplate is p n 102667 Figure 5 41 Quad Standard Decoder Line Doubler VIC faceplate with blank faceplate above it ...

Page 129: ...2 The System Controller PCB Raster Timing Generator PCB Video Processor PCB and the three VICs are connected into it directly All the other PCBs and Power Supplies are connected through jumpers and cabling Troubleshooting on the Backplane PCB The connectors on the Backplane PCB provide one of the more accessible places to probe voltages and signals that may be useful for troubleshooting purposes s...

Page 130: ...Voltage Power Supply J7 Pin Signal or Voltage Pin Signal or Voltage 8 LV_ENA 5 HV_OK 9 LV_OK 8 80 V 10 24 V_FANS 9 15 V 11 _5 1 V Stdby 10 15 V 12 5 1 V 11 G1 SUPPLY 13 6 2 V 12 VA_OK 14 15 V 1 4 GND 15 15 V 16 80 V 17 COVER_ON 18 FAN_ENA 1 7 GND Arc Lamp Power Supply 9 28 Pin Signal or Voltage see Figure 5 44 2 LAMP_LIT Pin Signal or Voltage 3 LAMP_OK 1 5 1 V Stdby 4 LAMP_ENA 2 GND 5 COVER_ON 3 C...

Page 131: ...Chapter 5 Electronics 5 76 Model 250 Service Manual Figure 5 44 Backplane Diagram right side ...

Page 132: ...Chapter 5 Electronics Model 250 Service Manual 5 77 ...

Page 133: ...l appearance to the projector however they also protect operators from exposure to high voltages and very bright light Review the Safety chapter and adhere to all warnings and cautions CAUTION Do not leave either cover in the tilted up position The covers can fall from this tilted up position and possibly damage projector components Remove the cover and set it aside when servicing the projector To...

Page 134: ...lifier PCB and its three associated CRT socket PCBs It is located in the rear of the projector The Electronics Module can be tilted to a 45 or 90 angle to access and perform service procedures on ILA s CRTs or the Video Amplifier PCB To tilt the Electronics Module up 1 Remove the rear cover 2 Unlatch the Electronics Module see Figure 6 1 3 The locking pin secures the Electronics Module in place at...

Page 135: ...e top of the Electronics Module and one large fan forces cool air into the body of the Electronic Module 3 fans in the Optics Module one fan draws hot air from the 1 Cold Mirror the other two fans draw hot air off of the Prism Assembly 3 fans for the Arc Lamp Module one large fan is mounted on the door of the Arc Lamp housing with one smaller fan mounted on the top The large blower is on the side ...

Page 136: ... 6 5 IR Detectors The IR Detectors receive command signals from the IR Remote Control The Model 250 projector has two IR Detectors one on the front of the projector and one on the rear mounted on the System Controller PCB The command signals go to the System Controller PCB where they are distributed to the various PCBs typically by way of the IIC data bus The IR Detectors can receive commands from...

Page 137: ...ed air such as Office Duster or Aero Duster or removing fingerprint smudges use Kodak Lens paper or equivalent from the projection lens As much as possible clean the optics only when absolutely necessary Projection Lens Use lens paper and wipe the lens clean in a vertical motion from top to bottom Use compressed air to blow excess dust from the lens An optical lens cleaning solution can also be us...

Page 138: ...Chapter 6 Miscellaneous Items 6 6 Model 250 Service Manual ...

Page 139: ...T Protection 7 19 7 4 Error Codes 7 22 7 5 Troubleshooting Guide 7 25 Troubleshooting on the Backplane PCB 7 26 7 1 Safety CAUTION Before performing procedures in this chapter review the chapter on Safety at the beginning of this manual WARNING When performing troubleshooting procedures that require projector covers to be off wear high voltage gloves ANSI ASTM 10 000 volt rated when working near t...

Page 140: ... normally When the LED is illuminated orange the projector is in standby mode which means that the projector has AC power but has not yet received a POWER ON command If the LED is illuminated flashing red the projector has experienced an error and will display an error code see Table 7 1 and Table 7 2 Service Mode Switch The Service Mode Switch is used when updating software to the CPU The project...

Page 141: ... sensor detects commands from the IR Remote Control included with the projector There is another IR Detector on the front of the projector Switch Block The Switch Block controls various parameters of the CPU Most of the switches are for diagnostic functions performed at the factory and will not need to be changed They should all be in the DOWN position The switch that will be of most concern to th...

Page 142: ...r recently turned off the cooling fans were still running at the time the CPU locked up it is very important to turn the AC Circuit Breaker back on immediately to power ON the cooling fans The cooling fans are needed to cool down the Arc Lamp Optics and PCBs properly to avoid damage to optical and electronic components If the Reset Switch is used the cooling fans will stop momentarily and begin op...

Page 143: ...igure 7 4 Video Processor Test Points and LEDs Video Processor Test Points The test points on the Video Processor PCB are visible and accessible from the left side of the Electronics Module when the rear projector cover is removed The test points can be grouped into four categories ...

Page 144: ...or the red output image signal G video for the green output image signal and B video for the blue output image signal The video signal is the image signal leaving the Video Processor PCB and going to the Video Amplifier PCB Ground The Gnd test point is for reference ground The other test point on the Video Processor PCB is for the Clamp signal which is not very useful for troubleshooting purposes ...

Page 145: ...Chapter 7 Troubleshooting Model 250 Service Manual 7 7 Raster Timing Generator PCB LEDs Figure 7 6 Raster Timing Generator LEDs ...

Page 146: ...ED would be illuminated green if the input source had separate horizontal and vertical syncs The following list gives a brief description of the each LED and its associated sync type SEP Separate horizontal and vertical sync inputs COMP Composite Red Green Blue Horizontal and Vertical signals all combined into one signal INT Internal sync means there is no input source sync signal present so the S...

Page 147: ...eshooting Model 250 Service Manual 7 9 Convergence Deflection PCB LED Figure 7 7 Convergence Deflection PCB LED The Convergence Deflection PCB has only one LED It illuminates green when power 15 V is present on the PCB ...

Page 148: ...er PCB LED The VA_OK LED on the Video Amplifier PCB is illuminated green when all the CRT deflection circuits are operating properly DEFL_OK the supply voltages 15 V 6 2 V and 80 V are present at the Video Amplifier PCB and all the CRT Yoke connectors are properly installed see Figure 7 15 and Figure 7 16 ...

Page 149: ...ht side exposed side of PCB The Backplane has two status LEDs the LV_OK signal from the Low Voltage Power Supply and the HV_OK signal from the High Voltage Power Supply The Backplane also has several connectors that can be used for probing signals and voltages see Figure 7 18 and associated signals and voltages ...

Page 150: ...rs The Low Voltage Power Supply also puts out the 24 V Standby voltage FAN_ENA goes low that provides power to the cooling fans The cooling fans run from the time the AC Circuit Breaker is powered ON until approximately ten minutes after the projector receives a power Off command AC Circuit Breaker still on When the projector receives a power ON command from the IR Remote PC or Laptop the System C...

Page 151: ... the Igniter drops to between 25 V and 31 V The voltage from the Arc Lamp Power Supply stays at a steady output of 2 kW during normal operation of the projector When the projector receives a power OFF command the LAMP_LIT and the LAMP_ENA signal both go high This shuts off the Arc Lamp Power Supply The FAN_ENA signal stays low for an additional ten minutes allowing the cooling fans to cool down th...

Page 152: ... green and blue color components and horizontal and vertical syncs in the VIC The separated image and sync signals go to the Video Processor PCB In the Video Processor PCB the image signals are modified with Brightness Contrast Gamma Correction Sensitivity and Threshold The modified image signals go to the Video Amplifier PCB where they are go through an amplifier and on to the CRTs The horizontal...

Page 153: ...er a Switched Mode Power Supply that generates the horizontal deflection sawtooth waveform The Raster Timing Generator PCB divides the range of horizontal scan frequencies into four groups or bands because the retrace or flyback timing varies dramatically from the lowest frequency 15 kHz to the highest frequency 90 kHz The Horizontal Vertical Deflection PCB generates the horizontal waveforms that ...

Page 154: ...nd generates a sawtooth waveform V_RAMP It sends this signal to the Vertical Amplifier on the Horizontal Vertical Deflection PCB It also sends geometric correction to modulate the vertical deflection waveform V_PARAB to the Horizontal Vertical Deflection PCB The Convergence Deflection PCB sends convergence correction data received from the System Controller PCB to the Scan Reversal PCB X_RED GRN a...

Page 155: ...Chapter 7 Troubleshooting Model 250 Service Manual 7 17 Figure 7 13 CRT Deflection path between Horiz Vert Deflection PCB Convergence Deflection PCB and Scan Reversal PCB ...

Page 156: ...Chapter 7 Troubleshooting 7 18 Model 250 Service Manual Figure 7 14 CRT Deflection path between the Scan Reversal PCB and CRT ...

Page 157: ... different ways On the Scan Reversal PCB there is a H_SENS and V_SENS signal for each CRT These sense lines detect the presence of the horizontal and vertical deflection waveforms The horizontal and vertical sense lines for each CRT combine into a RED GRN or BLU_DEFL_OK signal see Figure 7 16 These RED GRN or BLU_DEFL_OK signals combine into one DEFL_OK signal that goes back to the Horizontal Vert...

Page 158: ...d back to the Horizontal Vertical Deflection PCB The H_LOCK has 15 V applied to it on the Horizontal Vertical Deflection PCB If all the CRT Yoke connectors are properly installed H LOCK and H_LOCK will both measure 5 V If the any one of the connectors is not properly installed H_LOCK will measure 15 V and H_LOCK will measure 0 V If H_LOCK is at 0 V This shuts down the horizontal amplifier circuit ...

Page 159: ...Chapter 7 Troubleshooting Model 250 Service Manual 7 21 Figure 7 16 CRT Protection path between the Scan Reversal PCB and CRT ...

Page 160: ...HER EXTRON or JVC Video Switcher Handler 7 ANSI OUTPUT ANSI Output Display process 8 UI CHAN SRC User Interface VIC Configuration Handler for Channel SRC Data 9 VIDEO INPUT CARD VIC Card Handler 10 HARDWARE Misc HW shutters etc The error codes listed in Table 7 2 describe problems associated with software Version 2 6 0 and hardware while the projector is operating The first column of the table lis...

Page 161: ...byte transfer NOTE This error occurs if the slave is missing During Power On this error is reported in the POWER category 4 1 CD PCA Missing No Slave Ack on first poll of Convergence Deflection PCB 4 2 CD PCA Not OK CD_OK is high BAD 4 3 HVD PCA Missing No Slave Ack status on first poll of Horizontal Vertical Deflection PCB 4 4 HVD PCA Not OK HVD_OK is High BAD HVD_OK requires RTG Timing 4 5 VA PC...

Page 162: ...ssible baud rate error 6 2 No Char Repeat Expected data characters to be repeated failed 6 3 Invalid Format Data not in Extron or JVC Switcher format 7 1 Write Len Error Ansi Output to RS232 port was interrupted incomplete 8 1 VIC Slot is empty User has selected a Channel VIC is not present 8 2 VIC Type Changed User has selected a Channel VIC type has changed User may have swapped a VIC into an in...

Page 163: ...ling interlock switch Reposition projector cover Section 6 1 No Picture Correct channel input VIC selected Select correct channel and VIC User s Guide section 4 6 Arc Lamp turned off Restart projector User s Guide 4 3 System power turned off Restart projector User s Guide 4 3 Signal source Verify signal source is turned on and properly connected User s Guide 3 5 HIDE command invoked Unhide image w...

Page 164: ...n the Backplane PCB The connectors on the Backplane PCB provide one of the more accessible places to probe voltages and signals that may be useful for troubleshooting purposes see Figure 7 18 and associated list of signals and voltages Figure 7 17 Backplane Diagram left side ...

Page 165: ...oses Low Voltage Power Supply J8 High Voltage Power Supply J7 Pin Signal or Voltage Pin Signal or Voltage 8 LV_ENA 5 HV_OK 9 LV_OK 8 80 V 10 24 V_FANS 9 15 V 11 _5 1 V Stdby 10 15 V 12 5 1 V 11 G1 SUPPLY 13 6 2 V 12 VA_OK 14 15 V 1 4 GND 15 15 V 16 80 V 17 COVER_ON 18 FAN_ENA 1 7 GND Arc Lamp Power Supply 9 Pin Signal or Voltage 2 LAMP_LIT 3 LAMP_OK 4 LAMP_ENA 5 COVER_ON 1 6 GND ...

Page 166: ...Chapter 7 Troubleshooting 7 28 Model 250 Service Manual Figure 7 19 Backplane Diagram right side ...

Page 167: ...Chapter 7 Troubleshooting Model 250 Service Manual 7 29 ...

Page 168: ...Plus fax modem software is required to perform update Boot Manager Software and System Software are separate products Each may be updated independently The System Software will depend on a specific version of the Boot Manager Refer to the System Software release bulletin for Boot Manager version dependencies To perform software upgrade 1 Verify that the projector circuit breaker is off Use a Null ...

Page 169: ...her SCB switches 1 2 and 3 are in the Down position 8 Turn the projector circuit breaker on while depressing and holding down the service mode switch on the System Controller PCB see Figure 7 1 Verify that Boot Manager appears on the terminal monitor The Power On LED stays Red Alternate for Step 9 In Power Off Standby mode Press Control Shift _ underscore hex IF international keyboard may vary in ...

Page 170: ...ecords processed 823 Upload Successful Address Range 0x00000000 0x00006687 Bytes Loaded 26248 WARNING FLASH WILL NOW BE UPDATED Press Enter to continue Esc to abort 11D The system has verified that the load module is correct and is ready to update the Flash Press Enter to perform the update press Esc now to abort the update with no changes While the Flash memory is being updated 15 30 seconds DO N...

Page 171: ...del 250 software Select file named zsys hex Press OK to start upload Uploading takes about 20 minutes 9600 bps 12D During upload a progress indicator updates the number of records received When the upload is complete the system will display the following numerical values are for example only and depend on the System Software version S Records processed 11282 Upload Successful Address Range 0x00020...

Page 172: ...r controlling the projector via an ANSI TERMINAL see section 8 3 Terminals and Protocol Note 2 Export Import can be performed on either Port A or Port B The Port must be configured for ANSI Terminal Port A speed is determined by DIP SWITCH 4 on the System Controller board UP is 9600 baud DOWN is 19200 Baud Port B can be configured for 2400 9600 default or 19200 through the Comm Setup Menu If both ...

Page 173: ...le 5 Directories set directory to desired download directory C TEMP 6 File Name Type desired File Name for example export1 txt 7 Select OK with mouse or press Enter key dialog will be removed 8 Verify TERMINAL screen shows status line at bottom Stop Pause Bytes 0 Receiving EXPORT1 TXT 9 Model 250 Menu Press ENTER key to start export download NOTE Some VT100 Emulator programs ProComm will send the ...

Page 174: ...the Import Data The Windows TERMINAL Transfers Send Text File dialog box will default to the C windows directory which contains several txt files SETUP TXT is NOT a Projector EXPORT file 2 Import will alter all projector setup data Prior to starting several warnings are displayed to prevent unintentional loss of setup data 3 Model 250 Menu 7 System 5 Maintenance 6 Import WARNING Importing New Conf...

Page 175: ...plete or an error occurs or the User Aborts Expect 10 minutes to import 20 sources 500 000 bytes at 9600 baud 6 6 At successful end TERMINAL will remove the bottom line 7 Model 250 Menu When the projector detects the successful end of the transfer the following screen is displayed Import Configuration IMPORT COMPLETE New Configuration is active Press ESC to Continue Press ESC to exit the projector...

Page 176: ... end the Host Upload transfer 9 2 Model 250 Menu THEN press ESC to exit the projector Import operation and return to the Maintenance Menu There is a 10 second pause before the screen is redrawn Null Modem Adapter A Null Modem Adapter is needed to import data to or export data from the Model 250 Projector The Null Modem Adapter allows the projector to communicate to a PC or Laptop computer through ...

Page 177: ...Select DEC VT 100 ANSI may already be selected 4 Use a Null Modem cable to connect between the projector and the terminal 5 Use the TERMINAL PREFERENCES and COMMUNICATIONS PROTOCOL below for Windows setup Terminal Preferences Select SETTINGS again from the menu bar Select TERMINAL PREFERENCES Set the following modes Table 8 1 Terminal preference settings Line Wrap Yes CR CR LF Local Echo No Inboun...

Page 178: ... the file VT 100 TRM with the above parameters saved for future use Table 8 3 VT 100 Terminal and Remote Command Equivalents Action Keyboard Input Executive Remote Keys Service Remote Keys Dec Hex Power OFF All CTRL F 6 6 Power ON All CTRL U 21 15 Power ON OFF CTRL P POWER POWER 16 10 Power ON OFF Electronics only CTRL E 5 5 Power ON OFF Lamp CTRL L 12 0C Left Arrow Left Arrow Left Arrow Left Arro...

Page 179: ...NS Arrows 65 41 Linearity H V RGB L LIN 76 4C Menu Spacebar MENU MENU 32 20 Mode M MODE MODE 77 4D Numeric 0 9 0 9 0 9 48 57 30 39 Onscreen O ONSCRN ONSCRN 79 4F Phase H PHASE 72 48 Picture sharpness X SHARP SHARP 88 58 Picture tint Z TINT TINT 90 5A Pincushion H V N PIN 78 4E RGB toggle R RGB RGB 82 52 Size H V S SIZE 83 53 Test pattern display T PATTERN 84 54 Skew H V RGB W SKEW 87 57 Threshold ...

Page 180: ...Bracket and A B C or D depending on which arrow Is pressed The first number represents the Escape key the second number represents the Left Bracket and the third number represents the letter corresponding to the Arrow Key pressed Refer to Section 8 1 Software Updating Must be done for a software change or port configuration change device speed to take effect ...

Page 181: ...Chapter 8 Software and Protocol 8 14 Model 250 Service Manual ...

Page 182: ...Blue 14 for Green 15 for Red 16 102630 Lens Relay 106533 Manual Operation User s Guide 106785 Manual Service 106784 PCA Convergence Deflection 105210 PCA Horizontal Vertical Deflection 106838 PCA Raster Timing Generator 105238 PCA System Controller 104678 PCA Video Amplifier 105232 PCA Video Processor 105234 PCA Backplane 102595 PCA Graphics Enhancer Plus RGBHV VIC 106183 PCA RGBHV VIC 102597 PCA ...

Page 183: ...02566 Power Supply Low Voltage 102520 Prism Tank Assembly 103942 Projection Lens 0 96 1 Fixed 105134 Projection Lens 1 5 1 Fixed 106687 Projection Lens 2 4 1 Fixed Simulator 103592 Projection Lens 5 6 1 Fixed 104337 Projection Lens Zoom 2 1 4 1 103746 Remote Control Executive 105576 Remote Control Service 105575 Remote Control Tethered Technician 105245 Yoke Assembly CRT 103467 ...

Page 184: ...a list of the spares that HJT recommends for one to four projectors Table 9 2 Recommended minimum spares Part no Description Quantity 105236 PCA Horiz Vert Deflection 1 105210 PCA Conv Defl 1 105232 PCA Video Amplifier 1 105234 PCA Video Processor 1 104678 PCA System Controller 1 105238 PCA Raster Timing Gen 1 102585 PCA Scan Reversal 1 102597 PCA Graphics Enhancer Plus VIC 1 102520 Low Voltage Po...

Page 185: ...Chapter 9 Parts List 9 4 Model 250 Service Manual ...

Page 186: ...more information or picture detail capability Chrominance Abbreviated as C The portion of the YPbPr and S image signal that contains the color information signal Cold Mirror Mirror that absorbs infrared light so that its reflection contains only cold light or light that does not transmit appreciable heat Because of this absorption of infrared heat radiation cold mirrors get quite hot Cross member ...

Page 187: ... or tint control on a display device adjusts red green balance Ignitor Provides a momentary high voltage to excite the gases in the Xenon Arc Lamp to ignite Image Light Amplifier A device that uses low intensity images to phase ILA modulate a high intensity light through a liquid crystal layer It is a key component in producing very bright high resolution images from Hughes JVC large screen projec...

Page 188: ...solution is expressed as the number of horizontal dots columns by the number of vertical lines rows For example a 680 x 400 resolution means 680 dots across each of 400 lines Retrace The blanked out line traced by the scanning beam of a picture tube as it travels from the end of any horizontal line to the beginning of either the next horizontal line or field The beam is turned off during retrace R...

Page 189: ...horizontal and vertical CRT deflection Signals included with the source input that control the monitor s scan circuits to properly time the lines and frames of a picture Source input The source of image and sync signals being input into the projector Typical source inputs are Computers VCRs Image generators Satellite feed Technician Remote Remote control used during Model 250 setup and adjustment ...

Page 190: ...can Frequency The number of times per second a display image is written or refreshed Vertical Scan Reverses the image vertically for use with Reversal Jumper mirror bounced displays Located on the Scan Reversal PCB Vertical Synchronization The number of times per second a frame is Frequency transmitted to a video display screen Xenon Arc Lamp See Arc Lamp ...

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