Service Manual ViewSonic VG921m-4 Model No. VS11369 19” Color TFT LCD Display (VG921m-4_SM Rev. 1a Nov.
Copyright Copyright © 2006 by ViewSonic Corporation. All rights reserved. No part of this publication may be reproduced, transmitted, transcribed, stored in a retrieval system, or translated into any language or computer language, in any form or by any means, electronic, mechanical, magnetic, optical, chemical, manual or otherwise, without the prior written permission of ViewSonic Corporation.
TABLE OF CONTENTS 1. Precautions and Safety Notices 1 2. Specification 4 3. Front Panel Function Control Description 18 4. Circuit Description 24 5. Adjustment Procedure 31 6. Troubleshooting Flow Chart 55 7. Recommended Spare Parts List 63 8. Exploded Diagram and Exploded Parts List 66 9. Block Diagram 68 10. Schematic Diagrams 69 11.
1. Precautions and Safety Notices 1. Please carefully read this manual before operating the device and keep it available for future reference. 2. To avoid the danger of the monitor falling and thereby possibly causing injury and/or serious damage to the monitor itself, do not place it on unstable cars or desks. Be careful to avoid placing any stress on the LCD screen during handling. 3.
Handing and Placing methods Correct methods Incorrect methods Only touch the metal frame of the LCD panel or the Surface of the LCD panel is pressed by fingers and that front cover of the monitor, DO not touch the surface of may cause”mura” the POL Taking out the monitor by grasping the LCD panel, that Take out the monitor with cushions May cause”mura” Placing the monitor on a foreign objects, that could Place the monitor on a clean and soft foam pad ViewSonic Corporation scratch The surface of
The panel is placed facedown the lap,that may cause "mura" ViewSonic Corporation 3 Confidential - Do Not Copy VG921m-4
2. Specification Introduction 1 LCD PANEL st (1 source) Panel: HSD190ME13-A16 Size 19" Color a-Si TFT Active Matrix 1280x1024 LCD Pixel Arrange 0.294 mm x 0.294 mm Glass Treatment Anti-Glare, Hard coating (3H) Contrast Ratio 700 :1 Viewing Angle CR >= 10 150/135 (degrees; typ) CR >= 5 160/155 (degrees; typ) Colors 16.
Power 7 POWER Voltage Consumption AC 100-240V (Universal); 50-60 Hz Typ/Max 32 W / 36 W 20±2 ~ -5±2 degrees 8 ERGONOMICS Tilt 9 CONTROLS Physical Key buttons [PW], [Mute], [ 2 ], [Up], [Dn], [ 1 ] OSD Function Main Menu Auto Image Adjust Contrast/Brightness Color Adjust sRGB, 9300K, 7500K, 6500K, 5400K, User Color [R, G, B] Information Manual Image Adjust Horizontal Size, H/V Position, Fine Tune, Sharpness Setup Menu Language Select, Resolution Notice, OSD Position, OSD Time Out, OSD Backgroun
14 15 Packing 497 mm (W) x 516 mm (H) x 158 mm (D) (W x H x D) 19.6" (W) x 20.3" (H) x 6.2" (D) WEIGHT Net 5.3Kg (11.7 磅) Gross 6.6kg(14.
Product definition and specification Product Name ViewSonic VG921m Oracle item# VG921M-4 Model Number OSD Languages VS11369 English, French, German, Italian, Spanish, Finnish, Japanese, Traditional Chinese, Simplified Chinese TFT LCD Panel and Model # HSD190ME13-A16 Scalar Realtek RTD2023L Input Signal Analog x1 Sync Compatibility Separate Sync / Composite Sync / SOG Adapter Internal Power Board Yes, refer to APPENDIX B: Power Cable Power Cable Analog Cable (1.
4-1 GENERAL specification Test Resolution & Frequency 1280x1024 @ 60Hz Test Image Size Full Size Contrast and Brightness Controls Factory Default: Contrast = 70%, Brightness = 100% 4-2 VIDEO INTERFACE Input Connector (refer the Appendix A) DB-15 Default Input Connector Defaults to the first detected input Video Cable Strain Relief Equal to twice the weight of the monitor for five minutes Video Cable Connector Pin out Refer to Appendix A; Compliant DDC/2B Video Signals Video RGB (Analog) Separ
4-4 POWER SUPPLY Internal Power Supply Input Voltage Range Part Number:PI-SB03 100to 240VAC Input Frequency Range 50 to 60 Hertz Short Circuit Protection OUTPUT CAN BE SHORTED WITHOUT DAMAGE Over Current Protection 6 A TYPICAL AT 5 VDC Leakage Current 1.0 MA (MAX) AT 264VAC / 60HZ Efficiency 80 % TYPICAL AT 115VAC FULL LOAD Fuse INTERNAL AND NOT USER REPLACEABLE Power Dissipation 32 WATTS (TYP) Max Input AC Current 1.2 ARMS @ 90VAC, 0.
4-5 ELECTRICAL REQUIREMENT Horizontal / Vertical Frequency Horizontal Frequency 24 – 82 kHz Vertical Refresh Rate 50 – 75 Hz Maximum Pixel Clock 135 MHz Sync Polarity Independent of sync polarity Timing Table SOG Timing Composite Separated Item Digital - TMDS Analog Remark 1 640 x 350 @ 70 Hz, 31.5 KHz 2 640 x 400 @ 60 Hz, 31.5 KHz 3 640 x 400 @ 70 Hz, 31.5 KHz 4 640 x 480 @ 50 Hz, 24.7 KHz 5 640 x 480 @ 60 Hz, 31.
31 1280 x 960 @ 50 Hz, 49.4 KHz 32 1280 x 960 @ 60 Hz, 59.7 KHz 33 1280 x 960 @ 75 Hz, 75.2 KHz 34 1280 x 1024 @ 50 Hz, 52.7 KHz 35 1280 x 1024 @ 60 Hz, 64 KHz DMT 36 1280 x 1024 @ 75 Hz, 80 KHz DMT DMT *1. Tolerance ≧ ±2KHz (if no overlapping issue) *2. Any timing not in the list, it should display as normal or show on “OUT OF RANGE” OSD message without blanking. *3. The image quality of 85Hz mode might be worse than 75Hz.
4-6 FRONT PANEL CONTROLS AND INDICATORS Front Panel Hardware Controls Power Switch (Front Head) Power Control, soft Power Switch. Power LED (Front Head) Green – ON Orange – Power Saving Mode Dark = Soft Power Switch OFF Front Panel Controls (Head) [ ] [ 1 ] [ 2 ] [▲] [▼] [;X] Mute [ ] Power [ 1 ] BUTTON 1 [ 2 ] Button 2 [▲] UP ARROW BUTTON [▼] DOWN ARROW BUTTON Note: Power Button, Button 1 and Button 2 must be one-shot logic operation. (i.e.
Function descriptions Main Menu Controls The Main Menu OSD includes most of control functions. Please refer to APPENDIX C (Main Menu OSD Table) for the detail. OSD Lock short cuts function for the buttons The OSD lock will be activated by pressing the front panel control buttons "(1), & (▲)" for 10 seconds. If the user then tries to access the OSD by pressing any of the buttons "1", "▼", "▲", "2" a message will appear on the screen for 3 seconds showing "OSD Locked".
Resolution Notice Actions 1. Resolution Notice OSD should show on screen after changing to non-native mode for 30 sec 2. For auto input select function, it shall meet the requirement in Appendix D. 3. The OSD should disappear after 10 sec or by pushing button [1] or [2] Resolution Notice function should be disabled when push button [2] under Resolution Notice OSD 0-Touch™ Function Actions 1. Execute Auto Image Adjust when new mode detected, and save the settings to buffer for further use 2.
4-8 TFT LCD PANEL Panel Characteristics : 1st Source Panel Model number HSD190ME13-A16 Type Active Matrix TFT, TN technology Active Size 19” (337.8mm x 301mm) Pixel Arrangement RGB Vertical Stripe Pixel Pitch 0.
4-9 IMAGE PERFORMANCE Display Size Horizontal Display Size, Primary Preset Full Screen Vertical Display Size, Primary Preset Full Screen Luminance Lv (Max) –Condition: Brightness / Contrast = 100% CCT = USER COLOR (R/G/B=100%) Lv (Max) = The Luminance requirement of section 4-6 “TFT LCD PANEL” Lv (Def) –Condition: Brightness / Contrast = 100% Lv (Def) / Lv (Max) x 100% > 95% Color Temperature = 6500K / sRGB Lv (sRGB/6500K) –Condition: Brightness / Contrast = Default Lv (sRGB/6500K) / Lv (Max) x 100%
Contrast Ratio CR(Max) –Condition: Contrast / Brightness = 100% CCT = USER COLOR (R/G/B=100%) Same as the Contrast Ratio in section 4-6 “TFT LCD PANEL” CR(6500K) –Condition: Contrast / Brightness = Default CR(6500K) / CR(Max) ≧ 85% CCT = 6500K Saturation Contrast = Default Brightness = Default Test pattern = 128-gray Contrast = 100% Brightness = 100% Test pattern = 64-gray NO VISIBLE SATURATION * ≧50% UNITS OF SHIPMENT SHALL BE EQUAL OR BETTER THAN TYPICAL CR SPEC.
3. Front Panel Function Control Description Adjusting the Screen Image Use the buttons on the front control panel to display and adjust the OSD controls which display on the screen. The OSD controls are explained at the top of the next page and are defined in “Main Menu Controls” on page 10.
Do the following to adjust the display setting: 1. To display the Main Menu, press button [1]. NOTE: All OSD menus and adjustment screens disappear automatically after about 15 seconds. This is adjustable through the OSD timeout setting in the setup menu. 2. To select a control to adjust, pressSorTto scroll up or down in the Main Menu. 3. After the desired control is selected, press button [2]. A control screen like the one shown below appears.
Main Menu Controls Adjust the menu items shown below by using the up S and down T buttons. Control Explanation Auto Image Adjust sizes and centers the screen image automatically. Contrast adjusts the difference between the image background (black level) and the foreground (white level). Brightness adjusts background black level of the screen image. Audio Adjust Volume increases the volume, decreases the volume, and mutes the audio. Mute temporarily silences audio output.
Control Explanation User Color Individual adjustments for red (R), green (G), and blue (B). 1. To select color (R, G or B) press button [2]. 2. To adjust selected color, pressSandT. Important: If you select RECALL from the Main Menu when the product is set to a Preset Timing Mode, colors return to the 6500K factory preset. Information displays the timing mode (video signal input) coming from the graphics card in the computer, the LCD model number, the serial number, and the ViewSonic® website URL.
Control Explanation Fine Tune sharpens the focus by aligning text and/or graphics with pixel boundaries. NOTE: Try Auto Image Adjust first. Sharpness adjusts the clarity and focus of the screen image. Setup Menu displays the menu shown below: Language Select allows the user to choose the language used in the menus and control screens. Resolution Notice allows the user to enable or disable this notice.
Control Explanation OSD Position allows the user to move the OSD menus and control screens. OSD Timeout sets the length of time the OSD screen is displayed. For example, with a “30 second” setting, if a control is not pushed within 30 seconds, the display screen disappears. OSD Background allows the user to turn the OSD background On or Off.
4. Circuit Description A. AC-DC CONVERTER The power supply with a high-integrated green-mode PWM controller provides several features to enhance the performance of power flyback converters. U801 is a PWM controller and provides many protection functions. U802 is a photo couple to transfer the feedback signal from the second side which U803 detected both of the output DC voltage on 5V and 24V.
GREEN+ AI 34 Analog input from GREEN channel GREEN- AI 35 Analog input ground from GREEN channel ADCB_VDD AP 36 Analog power (3.3V) RED+ AI 37 Analog input from RED channel RED- AI 38 Analog input ground from RED channel ADC_GND AG 39 Analog ground ADC_GND AG 40 Analog ground ADC_VDD AP 41 Analog power (3.
Display & TCON/VIDEO-8 Port: 54 pins ■:LVDS+RSDS+TTLO ■:RSDS+TTLO ■:RSDS+TTLIO■:TTLO ■:TTLIO Pin 6-bits 6 bits 8/6 bits 8 bits 6 bits NO.
88 AB2N NC TECLKN ABLU [4]/T17 ABLU [4] 89 AB1P NC TECP ABLU [3]/T18 ABLU [3] 90 AB1N NC TECN ABLU [2]/T19 ABLU [2] 91 ACLKP NC TEBP ABLU [1]/T20 TCON [1] 92 ACLKN NC TEBN ABLU [0]/T21 TCON [0] 93 AG3P NC TEAP AGRN [7]/T22 AGRN [7] 94 AG3N NC TEAN AGRN [6]/T23 AGRN [6] 99 AG2P TCON [11] NC AGRN [5]/T24 AGRN [5] 100 AG2N TCON [10] NC AGRN [4]/T25 AGRN [4] 101 AG1P TCON [9] NC AGRN [3]/T26 AGRN [3] 102 AG1N TCON [8] NC AGRN [2]/T27 AGRN [2] 103
TMDS: 18 pins Name TMDS_TST/ PWM1 I/O Pin No Description Note AIO 9 TMDS_TEST Pin / PWM1 / Power-on-latch for serial / parallel port TMDS_GND G 10 TMDS_VDD P 11 EXT_RES A 12 TMDS_VDD P 13 RX2P I 14 Differential Data Input RX2N I 15 Differential Data Input TMDS_GND G 16 RX1P I 17 Differential Data Input RX1N I 18 Differential Data Input TMDS_VDD P 19 RX0P I 20 Differential Data Input RX0N I 21 Differential Data Input TMDS_GND G 22 RXCP I 23 Differential
DDCSDA / TCON [1] / PWM1 / IO 47 BBLU [0] DDC serial control I/F data input / (1), (2), (3), (5), (6), output / TCON [1] / PWM1 / TTL BBLU (8)/ 8mA /no slew [0] DDCSCL2 (HDCP) / TCON [5] I 126 DDC serial control I/F clock / TCON (2), (3), (5) [5] DDCSDA2 (HDCP) / TCON [7] IO 125 /PWM1 DDC serial control I/F data input / (1), (2), (3), (5), (6), output / TCON [7] / PWM1 (8)/ 8mA /no slew Power & Ground: 22 pins Name I/O Pin No Description 3.3V Power P 49,121 VCCIO: 2 3.
• Support external counters/timers, 1 & 2 • Single/double frequency clock output • Two external interrupts, INT1 is shared with Slave IIC interrupt source. • Maximum 4 channels of 6-bit ADC • Flash-ROM code protection selection • 44-pin PLCC package D. INVERTER In order to drive the CCFLs embedded in the panel module, there is a push-pull inverter to convert by the controller. from input 24V up to hundreds of AC voltage output peak to peak.
5. Adjustment Procedure 1. Function test 1.1 products: 19” LCD Monitor 1.2 test equipment: Color video Signal& pattern (Or PC with SXGA resolution and a sound card) 1.3 Test Condition: Before function test and alignment ,each LCD Monitor should be warmed up at least 30 minutes with the following conditions: A: in room temperature B with full white screen ,RGB ,and black C. with cycled display model: 1280 x 1024 @ 60Hz 1.4 Test display& Pattern 1.4.
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1. DDC Key In Procedure Note: After having assembled the monitor, please do the DDC Key In procedure. If you find the DDC does not conform to the monitor, please do the DDC Key In again. 1.
1.2 Setup Procedure 1.2.1 Open computer’s box cover, plug D8330 CORD in PCI slot, close cover and connect AC power, Monitor, Barcode Scanner, Mouse, Keyboard with PC 1.2.2 .1 Connect RS232-VGA cable to DDC RS232 OUT port of PC (if you do DDC Key In for D_SUB) 1.2.2.2 Connect RS232-DVI cable to DDC RS232 OUT port of PC (if you do DDC key In for D_DVI) 1.2.3 Turn on PC power, choose DDC Tester System application, run it 1.2.4 Connect AC power, RS232-VGA with VG930 Monitor. 1.2.
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1.4.0 DDC Key In Procedure Step 1 select and execute DDC Key In program (winDDC.
Step 2 Load DDC source file Step2.
Step2.
Step2.3 Step3 click “working Model”, select Model in list box Double click the “input barcode” icon at the toolbar, Key in the serial number or Use Barcode Scanner to scan the barcode of the monitor. And press the “enter” key.
Step 4 Checking Methods Step5.1 exit “winddc.exe”, take RS232-VGA cable out of the monitor, connect the monitor with a computer By the VGA lable Step5.2 open up the “my computer” attribute dialog box, select the “hardware” option, open “drive management”. Below the monitor catalog, uninstall the monitor. Step4.
Step4.2Select and click the “EDIDW2K.
Setp4.
Packing For Shipping and Disassembly Procedure 1. Take off the cover of the Bracket 2.
3.Take off the three screws from the housing 4.
5. Take off the Two Speakers 6.Pull off the cables which can fix up the speakers and then pull out the speaker cables 7.
8. Take out the screws from the key board 9.take off the AL foil (4pcs)from the lamp cable 10. Unscrew 3 pcs screws from the shield cover.
11 Take out the AL foil which connecter the power board and main board 11. Tear off the aluminum foil from the FFC cable 11.
12 Take out the power board connector and lamp wire 13.
14. Unscrew screws from the main board and take off the screws 15.
16.
17.
6. Troubleshooting Flow Chart Main Procedure Start Connect all of devices to the LCD monitor Power On Is indicator LED light? A.
1 Is backlight on? No B. Backlight Troubleshooting Yes Display Performance O.K.? No C. Performance Troubleshooting No D. Function Troubleshooting No E. Audio Troubleshooting Yes Function Adjustment O.K.? Yes Audio Function O.K.
A.
B.
C.
2 Screen with noise or line bar? Yes Prss Reset Button from front panel control Yes End No Change Main Board No Screen is smaller? Yes Make sure relution is set at default No Yes Reset O.K.
D.
E. Audio Troubleshooting Start Make sure sound output, Audio cable is OK.
7. Recommended Spare Parts List RECOMMENDED SPARE PARTS LIST (VG921m-4) ViewSonic Model Number: VS11369 Serial No. Prefix: QB9 Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Description Cable(CON).
BOM LIST (VG921m-4) ViewSonic Model Number: VS11369 Rev: 1a Serial No.
Item 80 81 82 ViewSonic P/N N/A N/A N/A 83 N/A 84 85 86 87 88 89 90 91 92 N/A N/A N/A C-00008184 N/A N/A N/A N/A N/A Ref. P/N M155223008401 M155223010401 M701900LM0200-E P212145102501 P212145102502 P704A995LM010-A P705A995LM050-A XLM19VA280001 P441500300001 P74AA995LM110-A XLM19VA380001 M711200LM0150-E P369579010001 ViewSonic Corporation Description SCREW STD 十/ P HEAD Φ3.0* L8mm NICKEL SCREW STD 十/ P HEAD Φ3.
8. Exploded Diagram and Exploded Parts List EXPLODED PARTS LIST (VG921m-4) ViewSonic Model Number: VS11369 Rev: 1a Serial No. Prefix: QB9 Item ViewSonic P/N 1 N/A 2 N/A 3 N/A 4 N/A 5 B-00008052 6 B-00008167 7 N/A 8 E-00005792 9 N/A 10 B-00008166 11 N/A 12 N/A 13 B-00008085 14 N/A 15 N/A 16 N/A 17 N/A 18 N/A 19 N/A 20 N/A 21 N/A 22 N/A 23 N/A 24 N/A 25 N/A 26 N/A 27 N/A 28 N/A 29 N/A 30 N/A 31 N/A 32 N/A 33 N/A 34 E-00008035 ViewSonic Corporation 66 Confidential - Do Not Copy VG921m-4 Ref.
PACKING PART LIST (VG921m-4) ViewSonic Model Number: VS11369 Rev: 1a Item 1 2 3 4 5 6 7 8 9 10 ViewSonic Corporation 67 Confidential - Do Not Copy VG921m-4 ViewSonic P/N P-00008175 P-00008173 P-00008174 CB-00006504 A-00006505 N/A N/A Ref.
ViewSonic Corporation 68 Speak er Out Line In Audio Amp.
10. Schematic Diagrams R2 NC/0 C1 C2 R3 0/NC 5V 5DVCC L1 FEB/1206 R5 100k + C6 R4 10K Q1 AO3401 2 3 40mil J1 3.3V 5V 100nF + 100uF_16V BKLT-VBRI BKLT-EN 1 2 3 4 5 6 R2 NC/0 FB1 FEB/1206 40mil PANEL_VCC C3 22uF/16V C4 100nF C5 0.01uF 100uF_16V 3 5V Q2 1 ONPANEL_5V R6 1K KST3904 DGND 2 CN1 2.0_11pin PANEL POWER 1 DGND C9 NC DGND 3.3V 5DVCC U3 L2 FEB/1206 VIN VOUT 2 3.
JP5 10 9 8 7 6 5 4 3 2 1 6 5 4 3 2 1 MUTE UP DOWN EXIT MENU POWER LED-2 LED-1 1 2 3 4 5 6 HEADER 13/SM A1 HEADER 13/SM 6 5 4 3 2 1 A2 10 9 8 7 6 5 4 3 2 1 JP3 JP4 LED1 2 4 SW6 HEADER 13/SM MENU EXIT DOWN UP MUTE DGND 1 3 2 SW1 4 1 3 2 SW2 4 1 3 2 SW3 4 1 3 2 SW4 4 1 3 2 SW5 4 C 1 3 1 2 3 4 5 6 ViewSonic Corporation Model Title Date ViewSonic Corporation 70 Confidential - Do Not Copy VG921m-4 Rev:
FBA2 3 FBA1 BED/6 5VA FEB/1206 5DVCC CA2 CA1 DGND 0.1uF 5VA 0.1uF AGND AGND CA13 CA11 + 100uF_16V 0.1uF AGND FBA7 3 STBY E RA3 15K 3 VOLUME CA3 10uF_16V CNA1 1 2 4 5 3 + RA4 10K RA6 10K FBA5 FBA4 BED/6 ROUT+ 2 3 RA5 RA7 CA10 47K NC/180PF 47K SHUTDOWN ROUT- 15 RIN- SE/BTL 14 GND GND 5 GND GND 12 CA4 6 VOLUME BYPASS 11 1uF 7 LOUT+ LOUT- 10 8 LIN- 1uF PHONEJACK 5P VDD 16 13 CA8 BED/6 CA6 NC/180PF 1 4 AGND FBA6 BED/6 BED/6 UA1 VDD CA15 NC/0.
MCU_VCC 1N4148 1D26 2 1N4148 D28 1 2 3 DGND 2N3906 R139 4.7K 3.3DVCC IICSDA IICSCL 10uF_16V R138 R140 100Ω 100Ω C121 100nF U4 8 5 6 4 5DVCCTEST SDA A2 SCL A1 GND A0 7 3 2 1 3 2N3906 R142 4.7K D29 1N4148 1 R143 R144 MCU_RESET 22 NC/4.7K D30 4.7K 1N4148 DGND 1 R145 NC/4.7K MCU_VCC RESET_MCU C124 100uF 100nF RP1 4 3 2 1 MCU_VCC C123 + 5 6 7 8 2 R137 4.7K X24C16 (SMD) Q11 0 472_4 RP2 4 3 2 1 3.3DVCC 4.
30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 XO Y1 24MHz R47 6.8KNC R3.3DVCC 2 XI RXE3+ RXE3RXEC+ RXECRXE2+ RXE2- 3.3DVCC FEB/1206 C28 22pF L9 3.3DVCC C29 C30 C31 100nF 100nF 100nF C32 + RXE1+ RXE1- C33 100nF RXE0+ RXE0RXO3+ RXO3RXOC+ RXOC- 22uF_16V DGND RXO2+ RXO2RXO1+ RXO1RXO0+ RXO0- RV1 0 CN2 Closed to Scaler C27 22pF CF1601S 30Pin-1.0H(Cvilux)(DIP) PANEL_VCC R1.8DVCC L10 FEB/1206 1.8CC C37 100nF R3.
R24 75 C15 U1 R26 DDC1_SCL DDCSCL 15 5 10 4 9 3 8 2 7 1 6 VSIN 14 HSIN 13 DDC1_SDA DDCSDA 12 DGND 11 D4 D5 UDZ5.
11.
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* Reader’s Response* Dear Readers: Thank you in advance for your feedback on our Service Manual, which allows continuous improvement of our products. We would appreciate your completion of the Assessment Matrix below, for return to ViewSonic Corporation. Assessment A. What do you think about the content of this Service Manual? Unit Excellent Good Fair Bad 1. Precautions and Safety Notices 2. Specification 3. Front Panel Function Control Description 4. Circuit Description 5. Adjustment Procedure 6.