SERVICE MANUAL COLOR MONITOR DELL E773c Series THESE DOCUMENTS ARE FOR REPAIR SERVICE INFORMATION ONLY. EVERY REASONABLE EFFORT HAS BEEN MADE TO ENSURE THE ACCURACY OF THIS MANUAL; WE CANNOT GUARANTEE THE ACCURACY OF THIS INFORMATION AFTER THE DATE OF PUBLICATION AND DISCLAIMS LIABILITY FOR CHANGES, ERRORS OR OMISSIONS.
1. SPECIFICATIONS FOR HP7550 SERIES COLOR MONITOR CRT : 43.2CM(17") 90 Deflection, 29mm Neck, 0.27mm Dot Pitch, Non-Glare Screen Viewable image Size: 40.6CM (16") diagonal Display Color: Unlimited Colors External Controls: Power On/Off, Power led, Function knob: Contrast, Brightness, H-Center, H-Size, V-Center, V-Size, Rotation, Pincushion, Trapezoid, Pin-Balance, Parallelogram, Color Temperature, Degaussing, Recall, Moire, Input Video Signal...
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14. Main dimensions / weight: Packed Monitor Monitor Width: 410mm 515mm Height: 402mm 464mm Depth: 420mm 570mm Weight: 15.5kg 17.5kg 15. Press the “MENU”funtion and don’t release it,then press power swith on,the monitor will enter the burn-in mode if it is no signal input. 16.
2. PRECAUTIONS AND NOTICES SAFETY PRECAUTIONS Observe all caution and safety related notes located inside the display cabinet. Operation of the display with the cover removed, may cause a serious shock hazard from the display power supply. Work on the display should not be attempted by anyone who is not thoroughly familiar with precautions necessary when working on high voltage equipment.
PRODUCT SAFETY NOTICE Many electrical and mechanical parts in this chassis have special safety visual inspections and the protection afforded by them cannot necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Before replacing any of these components read the parts list in this manual carefully.
3. OPERATING INSTRUCTIONS This procedure gives you instructions for installing and using the Color display. Position the display on the desired operation and plug the power cord into a convenient AC outlet. Three-wire power cord must be shielded and is provided as a safety precaution as it connects the chassis and cabinet to the electrical conduit ground.
4. ADJUSTMENT ADJUSTMENT CONDITIONS AND PRECAUTIONS Approximately 30 minutes should be allowed for warm up before proceeding. Adjustments should be undertaken only on those necessary elements since most of them have been carefully preset at the factory. 4-2 MAIN ADJUSTMENTS FUNCTION LOCATION DESIGNATION...
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H-SIZE V-MOIRE REDUCE H-CENTER H-MOIRE REDUCE V-SIZE MOIRE DISABLE V-CENTER H-REGULATION PINCUSHION V-REGULATION PARALLELOGRAM H-LINEAR PIN-BALANCE V-LINEARITY TRAPEZOID V-LINEARITY ROTATION TOP CORNER NO USE BOT CORNER NO USE CONTRAST MAX-HSIZE MODIFY BRIGHTNESS MAX-VSIZE MODIFY R-BIAS MAX-TRAPEZOID MODIFY G-BIAS BURN IN R-BIAS DEGAUSS R-GAIN...
3. White Balance adjustment: A. Choose key of OSD and press it for above 10s,then enter into factory setting area for modulation. B. Brightness & contrast ratio MAX, fix to G-BIAS,fix to 40. C. Raster Max modulation: Raster Pattern, adjust R or B bias and G2, make x=271±10, y=301±10, Y=1.50±0.2 cd/m D.
RELATIVE PLACEMENT OF TYPICAL COMPONENTS Purity Magnets 6-pole Convergence Magnets 4-pole Convergence Magnets Deflection Yoke 6. Convergence adjustment A. Produce a magenta crosshatch on the display. B. Adjust the focus for the best overall focus on the display. Also adjust the brightness to the desired condition. C.
5. CIRCUIT DESCRIPTION 5-1 MICRO CONTROLLER CIRCUIT MICRO Controller The IC101 contains a 6502/8051 8-bit CPU core, 512 bytes of RAM, 16K bytes of ROM,14 channel 8 bit PWM D/A converters, 2 channel A/D converters for key detection, one 8 bit pre-loadable base timer, internal H-sync and V-sync signals processor providing mode detection, watch- dog timer preventing system from abnormal operation, and an I²C bus interface.
5-3 TRANSISTOR & DIODE CIRCUIT LOCATION CIRCUIT FUNCTION DESCRIPTION D901~D904 Bridge Rectifier for AC Source D910 Clamp Diode for snub CKT D919 Rectifier for Output Voltage D922 Rectifier for Output Voltage D923 Rectifier for Output Voltage D925 Rectifier for B+ Supply D929 B+ Feed Back Rectifier from F.B.T Pulse IC901...
6.TROUBLE SHOOTING CHART 6-1 NO RASTER, CRT RELATIVE CIRCUIT PROBLEMS CHECK MAIN PCB POWER SUPPLY 55V, 12V, 80V,-12.5V CHECK POWER SAVING CIRCUIT, H-SYNC, V-SYNC SIGNAL Q909, Q910 CHECK THE HIGE VOLTAGE OF CRT REFER ITEM S.M.P.S ABOUT 24 ~ 26KV CHECK FAILSAFE CKT IC401 PIN 25 RELATIVE CKT CHECK THE VOLTAGE OF CRT...
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2.ABNORMAL VIDEO LEVEL ON SCREEN 3. ABNORMAL DDC (PLUG & PLAY) CHECK IC101 PIN 5 VOLTAGE ABOUT 5V CHECK ZD901 GOOD OR FAIL CHECK SIGNAL CABLE OR P803 HS,VS DATA OUTPUT...
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6-2 ABNORMAL DISPLAY 1.NO SIGNAL ON SCREEN...
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6-3 NO BLANKING CHECK THE RELATIVE CIRCUIT OF BLANKING CHECK THE RELATIVE CIRCUIT OF Q705 CHECK R879,D706,D863,C873 ON VIDEO PCB,CHECK G1 RELATIVE CIRCUIT FBT PIN 4 ON MAIN PCB 6-4 HOR./OSC/DEF/HV CIRCUIT FAULT 1. NO RASTER (DISCONNECT WITH SIGNAL CABLE) CHECK IC401 PIN 29 ABOUT 12 VDC CHECK IC401 PIN 29 RELATIVE CIRCUIT...
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6-5 ABNORMAL HORIZONTAL DEFLECTION 1. ABNORMAL HORIZONTAL WIDTH OF VIDEO READJUST H-WIDTH FUNCTION CHECK THE RELATIVE CIRCUIT OF Q404, Q405, & Q406 CHECK FBT B+ VOLTAGE ABOUT 62V AT FH=31KHz CHECK THE RELATIVE CIRCUIT OF SMPS. CHECK THE HV OF CRT ABOUT 24.5KV 2.
6-9 POWER SUPPLY TROUBLE SHOOTING CHART BEFORE CHECK SW.REG. PLEASE REFER TO THE POWER SUPPLY BLOCK DIAGRAM POWER SUPPLY OUTPUT: (A) VARIABLE OUTPUT : 58V - 145V (DEPENDING EPENDING UPON H.SYNC FREQUENCY) CONSTANT OUTPUT : 6.3V, 14V, -12V, 78V BEAD SET ABNORMAL VARIABLE OUTPUT MAKE SURE THAT THE VARIABLE...