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Service Manual

MP8670/8745/8755/8770 Multimedia

Projector

3M Visual Systems Division E. P. S. Service Documentation

Austin, Texas 78726-9000 78-6970-8985-8

Warranty and Limited Remedy. This product will be free from defects in material and manufacture for a period of

two years from the date of purchase. 3M MAKES NO OTHER WARRANTIES INCLUDING, BUT NOT LIMITED TO, ANY

IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. If this product is defective

within the warranty period stated above, your exclusive remedy shall be, at 3M’s option, to replace or repair the 3M product or

refund the purchase price of the 3M product. _______________________________________________________________

Limitation of Liability. Except where prohibited by law, 3M will not be liable for any loss or damage arising from this

3M product, whether direct, indirect, special, incidental or consequential regardless of the legal theory asserted.

Summary of content (60 pages)

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Service Manual MP8670/8745/8755/8770 Multimedia Projector Warranty and Limited Remedy. This product will be free from defects in material and manufacture for a period of two years from the date of purchase. 3M MAKES NO OTHER WARRANTIES INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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MP8670/8745/8755/8770 Table of Contents SECTION 1 ADJUSTMENTS 1-1 Adjustments ................................................................................................................................................ 1-1 1-2 Section Contents ......................................................................................................................................... 1-1 1-3 Machine Identification ..........................................................................................
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M Multimedia Projector MP8670/8745/8755/8770 Adjustments 1. Adjustments 1-1. Overview Make advanced adjustments to the MP8670/8745 in a clean environment with minimal dust and positive pressure. Some adjustment procedures require a dark room with a luminance of less than five (Lux). This section 1-2. Section Contents • Machine Identification • Technician Tools • Cleaning LCD Panels • Convergence • White Balance • Sample/Hold Timing • MP8670/8745 Verification Test Sheet. 1-3.
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3M Multimedia Projector MP8670/8745/8755/8770 1-4. 1-4-1. Adjustments Technician Tools Test Generator 3M recommends the Quantum Data™ 801GX Video Test Generator (shown) or Extron™ VTG200 Video Test Generator be used for all advanced adjustment procedures. Use for white balance adjustments. 1-4-2. Chroma Meter 3M recommends the Minolta™ CL100 Chroma Meter or equivalent. Use for white balance adjustments. 1-4-3.
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3M Multimedia Projector MP8670/8745/8755/8770 1-5. Adjustments Cleaning LCD Panels. Dust particles can accumulate on the glass covering the LCD panels causing spots on the projection image. Periodic cleaning is necessary to maintain a high quality projection image. 1-5-1. Test for Dust on the LCD Panels 1. Turn the main power switch to the on position. Note: Input needed to access Menu 2. On the remote control: • Press the Menu button. • Select the Image menu.
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3M Multimedia Projector MP8670/8745/8755/8770 1-6. Adjustments Convergence The purpose of this procedure is to properly check the Red, Green, and Blue liquid display (LCD) panels so that the three colors are aligned at the same location and at the center of the screen. This allows for projection of the color White. If it is determined that convergence is a problem, the entire LCD assembly must be replaced. 1-6-1.
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3M Multimedia Projector MP8670/8745/8755/8770 1-6-3. Adjustments Convergence Check Follow these steps to check the Red and Blue LCD panels with the Green panel. 1. Input the SVGA VESA (60) cross-hatch timing signal or equivalent. (MP8670). OR Input the XGA VESA (60) cross-hatch timing signal or equivalent. (MP8745). 2. Select red and green and check convergence. 3. Select blue and green and check convergence. 4. Select all three colors and check convergence. 5.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7. Adjustments White Balance The purpose of this procedure is to adjust the brightness quality of the color white in the projection image. 1-7-1. Necessary Tools • Minolta™ CL-100 Chroma meter or equivalent • Phillips Screwdriver • Quantum Data™ 801GX Video Test Generator or equivalent • MP8670/8745 Remote Control • Dark Room (Less than five Lux ambient light) • Flashlight. 1-7-2.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7-3. Adjustments Access Test Menu 1. Press the Menu button. 2. Press and hold Reset (approximately 5 seconds) to display the Test Menu. 3. The Menu at the right will appear. 4. Under Video, the following choices appear. • SECAM R-Y # • SECAM B-Y # • VI-BRIGHT # • VI-CONTRAST # 5. Under C.UNIF., the following will appear. • This function can be turned ON or OFF • No.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7-4. Adjustments S/H Timing Adjustment Adjustment Preparations 1. Use a SVGA (MP8670) or XGA (MP8745), VESA (60) timing signal to input a 0.7V p-p cross hatch signal. 2. Use H-PHASE in the Adjustment Menu to adjust the cross hatch pattern so it is most clearly visible. 3. Reset S/H. • Position the cursor on S/H in the adjustment Menu and Press the RESET key. Alignment 2 Adjustment Procedure 1.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7-5. Adjustments SUB POSITION Adjustment Adjustment Preparation: 1. Make this adjustment after completing S/H Timing Adjustment. 2. Use a SVGA (MP8670) or XGA (MP8745), VESA (60) timing signal to input a 0.7V p-p cross hatch signal. 3. Press the AUTO button on the Remote Controller. Alignment 2 Adjustment Procedure 1. Use the SVGA (MP8670 or XGA (MP8745) VESA (60) timing signal to input a 0.70V p-p frame signal. 2. Use S/H - SUB H POSI.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7-6. Adjustments Ghost Adjustment Adjustment Preparation: 1. Make this adjustment after completing SUB H POSI. 2. Use a SVGA (MP8670) or XGA (MP8745), VESA (60) timing signal to input a 0.7V p-p cross hatch signal. 3. Use H-PHASE in the Adjustment Menu to adjust the cross hatch pattern so it is most clearly visible. Alignment 2 Adjustment Procedure: 4. Display Ghost Test Pattern. 5. Use S/H – GHOST (R) to adjust so that the Red Ghost is at a minimum.
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3M Multimedia Projector MP8670/8745/8755/8770 Adjustments 6. Display Ghost Test Pattern. 7. Use S/H – GHOST (G) to adjust so that the Green Ghost is at a minimum. Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 Adjustments 8. Display Ghost Test Pattern. 9. Use S/H – GHOST (B) to adjust so that the Blue Ghost is at a minimum. Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7-7. Adjustments Flicker Adjustment 1. Make this adjustment after completing GHOST adjustment. 2. Use a SVGA (MP8670) or XGA (MP8745) VESA (60) timing sugnal to input a 0.35V p-p , R primary color Signal for every other line. 3. Use DAC-P – V.COM-R from the adjustment Menu to adjust Flicker to a minimum. 4. Use a SVGA (MP8670) or XGA (MP8745) VESA (60) timing sugnal to input a 0.35V p-p , G primary color Signal for every other line. 5. Use DAC-P – V.
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3M Multimedia Projector MP8670/8745/8755/8770 Adjustments (60) timing signal to input a 0.35V p-p , B primary color Signal for every other line. 7. Use DAC-P – V.COM-B from the adjustment Menu to adjust Flicker to a minimum. Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 Adjustments 1. 1-7. 1-7-8. NRSH Adjustment (Vertical Streak Adjustment) 1. Make this adjustment after completing Flicker Adjustment. 2. Use an SVGA (MP8670) or XGA (MP8745) VESA (60) timing signal to input a 0.7 V p-p, 16-step Gray Scale. 3. Use DAC-P – NRSH in the adjustment menu to adjust until vertical streaks are a minimum of every 6 or 12 dots. 4.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7-9. Adjustments White Balance Adjustment Make this adjustment after completing NRSH adjustment. 1. Use an SVGA (MP8670) or XGA (MP8745) VESA (60) timing signal to input a 0.7 V p-p, 16-step monochrome green signal. 2. Use DAC-P – SUB BRIGHT and DAC_P – SUB CONTRAST-G from the adjustment menu for optimum shading characteristics. √ Note Lock DAC-P – SUB BRIGHT – G at 30. Lock DAC-P – BLACK2-GAIN – G at 50.
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3M Multimedia Projector MP8670/8745/8755/8770 Adjustments 5. Use an SVGA (MP8670) or XGA (MP8745) VESA (60) timing signal to input a 0.52V p-p White signal. 6. Use DAC-P – SUB BRIGHT – R and DAC-P – SUB CONTRAST – B in the adjustment menu to adjust color coordinates in the center of the screen to the following: X = 0.280 ± 0.005 Y = 0.345 ± 0.01 (Medium brightness white level) 7. Repeat steps 4through 7, as necessary, to check, and readjust low and medium level brightness white balance. 8.
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3M Multimedia Projector MP8670/8745/8755/8770 1-7-10. Adjustments Color Uniformity Adjustment Adjustment Preparations: 1. Make this adjustment after completing the White Balance Adjustment. 2. This adjustment is to assure color uniformity over the entire screen. Adjust all 33 points in sequence, starting with the smallest signal. 3. Do not adjust point #1 because the brightness of the entire screen will be changed. 4. Only adjustment points #2 and #3 can be adjusted for the color green (G).
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3M Multimedia Projector MP8670/8745/8755/8770 Adjustment Procedure: 24 23 22 14 Adjustments V/6 1. Use an SVGA (MP8670) or XGA (MP8745) VESA (60) timing signal to input a 0.35V p-p G primary color signal (50% Green). 6 20 29 12 16 4 30 28 8 V/3 2. Measure the illumination at points No. 2 and No. 3. The Values should be: H/6 18 10 H/3 2 No. 2 = Y2 (lux) H/3 H/6 1 3 5 9 11 19 V/3 No. 3 = Y3 (lux) 3. Determine which point (No. 2 or No. 3 has the higher illumination. 4.
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3M Multimedia Projector MP8670/8745/8755/8770 7. The next adjustments will be to balance the color uniformity shown in gray at right. 24 23 22 14 Adjustments V/6 6 20 29 12 16 4 30 28 8 V/3 H/6 18 10 H/3 2 H/3 H/6 1 3 5 9 11 19 V/3 7 8. Next, measure the color coordinates of point 2. Adjust “R” and “B” of Point 2 until the color coordinates are: • x2 = x1 ± 0.01 • x2 = y1 ± 0.
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3M Multimedia Projector MP8670/8745/8755/8770 10. The next adjustments will be to balance the color uniformity shown in gray at right. 24 23 22 14 Adjustments V/6 6 20 29 12 16 4 30 28 8 V/3 H/6 18 10 H/3 2 H/3 H/6 1 3 5 9 11 19 V/3 7 11. Next, measure the color coordinates of point 10. Adjust “R” and “B” of Point 10 until the color coordinates are: • x10 = x1 ± 0.01 • x10 = y1 ± 0.
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3M Multimedia Projector MP8670/8745/8755/8770 14. The next adjustments will be to balance the color uniformity shown in gray at right. The following are visual color uniformity checks and adjustments for color uniformity of the periphery. 24 23 22 14 Adjustments V/6 6 20 29 12 16 4 30 28 8 V/3 H/6 18 H/3 10 2 H/3 H/6 1 3 5 9 11 19 V/3 7 15. Adjust points 18 through 21 to achieve color uniformity.
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3M Multimedia Projector MP8670/8745/8755/8770 16. The next adjustments will be to balance the color uniformity shown in gray at right. The following are visual color uniformity checks and adjustments for color uniformity of the corners. Adjustments 24 23 22 14 V/6 6 20 29 12 16 4 30 28 8 V/3 H/6 18 H/3 10 2 H/3 H/6 1 3 5 9 11 19 V/3 7 17. Adjust points 22 through 33 to visually achieve color uniformity in the corners.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2. Disassembly/Reassembly 2-1. Overview Disassembly and reassembly of the MP8670/8745 is done using the reference diagrams and the step by step procedures that follow. Many component disassembly steps build upon previous disassembly steps. Refer to previous disassembly steps as needed. For general operation instructions including air filter or lamp replacement, refer to the Operator’s Guide.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-1. Remove Top Cover ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove the top cover to access the internal projector components. 1. Remove one (1) screw on back of projector.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 6. Carefully lift front of top cover to the open position. 7. Remove ribbon cable at circuit board and release wire from plastic wire manager. 8. Reassemble in reverse order. 7 Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-2. Remove Main PWB Board ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. 9. Remove six (6) cable wire connectors. 10. Remove five (5) cable wire connectors.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-3. Remove Service Board ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover and main drive board. 1. Locate the service board. 1 2 2. Remove one (1) wire connector. 3.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-4. Remove Driver PWB Board ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover and main PWB board. 1. Release three (3) ribbon connectors.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-5. Remove RGB Input Board ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover, main PWB board and driver PWB board. 1.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-6. Remove Dichroic Optics Unit ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover, main board, drive board, ballast, DC power fan and lens. 1.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-7. Remove Lens Assembly ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover, main board, drive board, ballast, and DC power fan. 1. Remove two (2) screws securing filter to dichroic unit.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-8. Remove Ballast ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. 1. Remove two (2) screws securing bottom of ballast. 2. Remove two (2) wire connectors. 3. Remove one (1) screw securing metal clip. 4.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-9. Remove PWB Signal Board ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover, main board, drive board, lens assembly and dichroic unit. 1 1. Remove RGB input board. See Section 2-3-5. 2.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-10. Remove DC Power Fan ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover and main PWB board. 2 1. Remove two (2) screws securing fan grill and fan. √ Note These screws are different sizes.
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3M Multimedia Projector MP8670/8745/8755/8770 Disassembly/Reassembly 2-3-11. Remove Exhaust Fan ! WARNING To avoid electrical shocks, unplug projector power cord before performing any maintenance to electrical components. ! Caution To avoid burns to fingers, allow projector lamp and internal projector components to cool off prior to lamp removal or disassembly. Remove top cover. 3 1. Remove one (1) screw securing metal bracket. 2. Remove bracket. 3. Remove fan wire connector and remove fan 1 4.
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3M Multimedia Projector MP8670/8745/8755/8770 Troubleshooting 3. Troubleshooting This section provides flowcharts to aid in troubleshooting the 3M MP8670/8745 Multimedia Projector. 3-1. Troubleshooting Checkpoints The following troubleshooting checkpoints that will help you diagnose problems. Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 3-2. Troubleshooting Power Cannot Be Turned On Power Cannot be Turned On - AC On, No LED's Lit Check at operating mode Is Voltage Input at Pins 1, 4, 6 of EDS1 on the Main PWB at Standby Mode? No Yes 1 - (CHK0082): +12.5V 4 - (CHK0041): +6.6V 6 - (CHK0043): +17.0V Power Unit (Circuit) Filter PWB Fuse No Measure Voltage at Pin 28 of EDI1 on the Main PWB at Standby Mode. CHK0023 = L Disconnect ETEP from Main PWB.
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3M Multimedia Projector MP8670/8745/8755/8770 3-3. Troubleshooting Lamp Does Not Light Lamp Does Not Light Blinks No Set the Lamp Cover What is the State of LAMP Indicator during Operation? Is the Lamp Door Closed? Lit Not Lit? Change the Lamp.
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3M Multimedia Projector MP8670/8745/8755/8770 Troubleshooting 3-3. Lamp Does Not Light (continued) Continued from Previous Page Not Lit? Blinks What is the State of TEMP Indicator? Not Lit * Yes DC FAN (LAMP) Short Between Pin 1 and 3 of ELMF on the Main PWB and Retry. No Yes "H" = 5V * Yes DC FAN (EXHAUST) Is Pin 1 of EBAR on the Main PWB set to "H"? Retry after Shorting between Pin 1 and 3 of EBAF on the Main PWB and Retry.
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3M Multimedia Projector MP8670/8745/8755/8770 3-4.
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3M Multimedia Projector MP8670/8745/8755/8770 3-5.
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3M Multimedia Projector MP8670/8745/8755/8770 3-6. Troubleshooting No Picture – RGB or VIDEO No Picture RGB or VIDEO Check at operating mode with RGB1 or 2 input Is Voltage Input at Pins 4, 6, 8, 10, 12, 14 of EDS1 on the Main PWB? Yes No 4 : (CHK0041) : +6.6V 6 : (CHK0043) : +17.
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3M Multimedia Projector MP8670/8745/8755/8770 3-7. Troubleshooting No Sound No Sound Check at operating mode, RGB and VIDEO Input No Sound when VIDEO Signal Input (Sound is heard when RGB signal input) Is the Audio Signal Output at Pins 8, 10 of EVS1 on the Main PWB VIDEO Input Terminal? Yes No PWB Input Terminal VIDEO 8 Audio L 10 Audio R Signal PWB No Sound Both RGB and VIDEO Signal Input Speaker Signal PWB Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 3-8. Troubleshooting Cannot Control Mouse or RS232C Cannot Control Mouse or RS232C Check at operating mode Are the Signals Input at each Pin of EDI1 on the Main PWB? No RGB Input Terminal PWB Yes 26 (CHK0019) : Mouse 24 (CHK0020) : TXD 23 (CHK0021) : RXD Main PWB Pin No.
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3M Multimedia Projector MP8670/8745/8755/8770 3-9. Troubleshooting Can Not Control USB Mouse Can Not Control USB Mouse Is the Voltage at Pin 26 (CHK0019) of EDI1 on the Main PWB set to "H"? No Main PWB Yes RGB Input Terminal PWB Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 Troubleshooting 3-10. Signal Waveforms of P501, P601, and P701 (Input Signal is VGA3) pin 1 & 36 V COM p in 16 H M C pin 20 7.5V (DC) EG01 1 4 .5V E R 0 1 , EB 0 1 GND H DATA 200nS 9V p in 5 PCG 1H 1.8 4V 9V 1H 4V pin 21 ~ pin 28 HCP 1H 100nS 9V V DATA 2H 4V 9V 100nS p in 30, 31 SIG 1,2 4V 2V ~ 5V p in 8 VCP, pin 9 VCP 7.5V 1H 2C ~ 5V 9V 12.5V 1H 1H 4V 1H Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 Troubleshooting Signal Waveforms of P501, P601, and P701 (Input Signal is VGA3), Continued pin 30, 31 SIG 1,2 4.5V 7.5V 4.5V 1H 1H Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 Theory and Diagrams 4. Theory and Diagrams To truly understand what is taking place when making advanced projector adjustments, the following concepts must be introduced and explained. An understanding of these principles increases your efficiency when making advanced projector adjustments. • • • • • Theory of Operation Color Theory LCD Structure Theory Lamp Theory Optical System Layout 4-1.
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3M Multimedia Projector MP8670/8745/8755/8770 Theory and Diagrams Driver Board Refer to driver board information for video. RGB Out RGB out simply takes the information in its analog state and passes it through an amplifier to the terminal out. Additional electronic image smoothing occurs in the gate array of the MP8670/8745. 4-1-3. MP8670/8745 Circuitry Diagram Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 4-2. Theory and Diagrams Color Theory An understanding of color theory provides a background for making the convergence and white balance adjustments. 4-2-1. Color Color is a visual sensation that involves three elements; a light source, an object, and a viewer. Light is reflected and modified by an object, then reaches the receptors in our eyes and is interpreted by our brains into what we know as color.
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3M Multimedia Projector MP8670/8745/8755/8770 4-3. Theory and Diagrams LCD Structure Theory An understanding of LCD Structure theory provides a background for making the convergence adjustments discussed in section 6. MP8670/8745 are a 1.3” square, poly-silicon design. Each LCD panel is composed of a layer of liquid crystal cells, electrodes, and glass. LCD is the acronym for Liquid Crystal Display. The three LCD panels (Red, Green, Blue) in the 4-3-1.
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3M Multimedia Projector MP8670/8745/8755/8770 4-4. Theory and Diagrams Lamp Theory The MP8670/8745 with a DC 260 watt metal halide bulb is capable of producing 550+ lumens of uniform brightness across the entire projection image. The metal halide bulbs should never be touched. When oil from your skin touches the bulb, it provides a focal point for the lamp energy. The lamp burns hotter at that location and eventually burns through the bulb prematurely. Copyright  2000, 3M IPC. All Rights Reserved.
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3M Multimedia Projector MP8670/8745/8755/8770 4-5. Theory and Diagrams Optical System Layout The following diagrams illustrate the MP8670/8745 optics modules and how the light is directed throughout. Notice that the MP8670/8745 optics module is composed of a lamp, lenses, a ½ wave plate (polarizer) (that allows for passage of both horizontal and vertical light waves), mirrors, dichroic mirrors, polarizers and LCD panels. Component Description Lamp Projects light Mirror Reflects all light waves.