Service Manual ViewSonic VA503b-2 VA503m-2 Model No. VS11357 15” Color TFT LCD Display (VA503b-2_VA503m-2_SM Rev. 1a Aug.
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 9 4. Circuit Description 15 5. Adjustment Procedure 24 6. Troubleshooting Flow Chart 38 7. Recommended Spare Parts List 46 8. Exploded Diagram and Exploded Parts List 49 9. Block Diagram 54 10. Schematic Diagrams 55 11.
1. Precautions and Safety Notices 1. SAFETY PRECAUTIONS This monitor is manufactured and tested on a ground principle that a user’s safety comes first. However, improper used or installation may cause damage to the monitor as well as to the user. WARNINGS: z z z z z z z z This monitor should be operated only at the correct power sources indicated on the label on the rear of the monitor. If you’re unsure of the power supply in you residence, consult your local dealer or Power Company.
4. Handling and Placing Methods Correct Methods: Incorrect Methods: Only touch the metal of the LCD panel or the front Surface of the LCD panel is pressed by fingers and cover of he monitor. Do not touch the surface of the that may cause "Mura". polarizer. Taking out the monitor by grasping the LCD panel. That may cause "Mura". Take out the monitor with cushions.
Correct Methods: Incorrect Methods: Placing the monitor on foreign objects, That could scratch the surface of the panel or cause "Mura". Place the monitor on a clean and soft foam pad. The panel is placed facedown on the lap. That may cause "Mura".
2. Specification 1. INTPRODUCTION TFTLCD PANEL Input Signal Sync Compatibility Compatibility Power Voltage Power Consumption Audio Ergonomics OSD Control Dimension Weight Operating Condition Storage Condition Regulation FEATURES Size Luminance (Typ) Contrast Ratio (Typ) Colors (6 bits + 2 bits FRC) Response Time (Typ) Viewing Angle (H/V) Recommend resolution VA503b-2 / VA503m-2 15 “ 250 cd/㎡ 600:1 16.2 M 8 ms 150 ° / 130 ° 1024 x 768 @60Hz Analog (75ohms, 0.7/1.
Video Signals Video Impedance Maximum PC Video Signal Maximum Mac Video Signal DDC 1/2B Sync Compatibility Video Compatibility Resolution Compatibility Exclusions Video RGB (Analog) - Separate 75 Ohms (Analog) 950 mV with no damage to monitor 1250 mV with no damage to monitor Compliant with Revision 1.
5 ELECTRICAL REQUIREMENT Horizontal / Vertical Frequency Horizontal Frequency Vertical Refresh Rate Maximum Pixel Clock Sync Polarity 30 – 62 kHz 50 – 85* Hz. * When the resolution is set to 1024 x 768 , the vertical refresh rate may be up to 75 Hz; for other resolutions, the vertical refresh rate may be up to 85Hz. 80 MHz Independent of sync polarity. Timing Table Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Timing 640 x 350 @ 70Hz, 31.
Main Menu Controls Auto Image Adjust Contrast/Brightness*1 Audio Adjust (For VA503m only) Volume*3, Mute*3 Color Adjust sRGB, 9300K, 6500K(default), 5400, User Color [R, G, B] Information H Frequency, V Frequency, Pixel Clock, Resolution, Serial Number, Model Number, “www.ViewSonic.com” Manual Image Adjust H.
AUDIO INTERFACE (SPEAKER SPECIFICATION) --- (For VA503m only) Line input connection Line input signal Line input impedance Maximum power output (Electric) Signal to Noise Ratio Frequency response Distortion 3.5 mm stereo jack 1.0Vrms >10 kOhm 1 W @ < 8% distortion 50 dB 500 Hz – 20 Khz < 8 % THD (@1kHz) Vibration There should be no audible vibration with volume at 100%. (Input signal within 1.
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. Main Menu with OSD controls Front Control Panel shown below in detail Power light Green = ON Orange = Power Saving Displays the control screen for the highlighted control.
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 automatically sizes, centers, and fine tunes the video signal to eliminate waviness and distortion. Press the [2] button to obtain a sharper image. NOTE: Auto Image Adjust works with most common video cards. If this function does not work on your LCD display, then lower the video refresh rate to 60 Hz and set the resolution to its pre-set value.
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 displays the Resolution Notice menu shown below. Resolution Notice advises the optimal resolution to use.
4. Circuit Description 2. Electronic Circuit Theory 2.1 Switching Mode Power Supply 2.1.1 AC Current Input Circuit P801 is a connector for connecting AC Power. F801 is a fuse to protect all the circuit. AC input voltage is from 90V to 264V. R820 and R821 joined between two inputting main circuit to prevent man from shock. L801 is used to clear up low frequency wave. C801 and C806 are used to discharge the waves that L801 produced. High frequency waves are damped by C801 and C806.
2. 2 Inverter Circuit 2.2.1 Low voltage to high voltage circuit 14VDC provides the power for IC501; the control signals Brightness and ON/OFF come from I/F board. ON/OFF signal connect to pin10 of IC501 and makes IC501 enable. Brightness signal connect to pin4 of IC501 and regulates the panel brightness, R526, R529, C505 make up a network of delaying time circuit and R523, R524 make up a divided voltage network, C504 is used to dump noise.
2.3 I/F Board Circuit 2.3.1 Power Input +3.3V is from the power board and supply for U101(LD1117AL-1.8V)﹑U102(AT24C02N) ﹑U103(TSUM16AL) ﹑ U104(SST25VF010A) ﹑U105(AT24C04N) ﹑panel and LED. +1.8V output is generated from +3.3V through C104 and C105 filtering, and U101 outputs. +1.8V is only used for U105. 2.3.2 MCU & Scaler(TSUM16AL) The frequency of XTAL1 is 14.318MHz. U103 # 48 is defined as panel-enable. When the I/O port is low, Q106 and Q105 are conducted.
3. FACTORY PRESET TIMING TABLE TIMING 640x350@70Hz IBM 640x400@70Hz IBM 720x400@70Hz 640x480@50Hz VESA 640x480@60Hz 640x480@67Hz VESA 640x480@72Hz VESA 640x480@75Hz VESA 640*480@85Hz FH(KHz) FV(Hz) Sync Polarity 31.469 70.086 31.469 70.086 31.469 70.087 24.700 50.000 31.469 59.
T1 (ms) T2 (ms) T3 (ms) 0.5~10 0~50 > 200 T4 (ms) > 200 T5 (ms) 0~50 T6 (ms) ﹤100 T7 (ms) > 500 5. AC Outlet Pin Assignment Symbol Description 1 L Live 2 N Neutral 3 E GND 3 Pin 1 2 P801 6. Inner Connector Pin Assignment 6.1 CN501, CN502, CN503, CN504 (Connect to Panel Backlight, SM02B-BHSS-1-TB or equivalent) Pin Symbol Description 1 H.V. High voltage for lamp 2 L.V. Low voltage for lamp 6.2 CN101 (Power BD to Interface BD) Pin No. Symbol Description 1 VCC3.3 +3.4V INPUT 2 VCC3.
2 LED_GREEN Green LED lighting control 3 GND Ground 4 KEY_MENU/EXIT OSD page selection and exit 5 KEY_SELECT/AUTO Select control and auto adjustment control 6 KEY_POWER DC power on/off control 7 KEY_DOWN OSD “▼” control to adjust value to decrease 8 KEY_UP OSD “▲” control to adjust value to increase 6.4 CN103 (Connect I/F BD to panel, FI-X30S-H or Equivalent) Pin No.
Pin Symbol I/O 1 2 3 4 5 6 C L X S F D I I I O I I Description Control Line Sense External Current Limit Source of MOSFET(GND) Frequency Drain of MOSFET 7.2 IC501 (OZ9938GN, CCFL inverter controller IC) Pin No.
20 GIN0P I Analog green input 21 SOGIN0 I Sync-on-green input 22 RIN0M I Reference ground for analog red input 23 RIN0P I Analog red input 24 AVDD_ADC I ADC Power 25 REFM Internal ADC bottom de-coupling pin 26 REFP Internal ADC top de-coupling pin 27 HSYNC0 I Analog HSYNC input 28 VSYNC0 I Analog VSYNC input 29 GND 30 DDCA_SDA/RS232_TX I/O 31 DDCA_SCL/RS232_RX I/O 32 33 34 VDDP GND VDDC 35 GPIO_P15/PWM0 36 37 38 39 40 41 42 NC SDO SCZ SCK SDI NC GPIO_P22 I/O
61 LVA2M O A-Link Negative LVDS Differential Data Output 62 LVA1P O A-Link Positive LVDS Differential Data Output 63 LVA1M O A-Link Negative LVDS Differential Data Output 64 LVA0P O A-Link Positive LVDS Differential Data Output 65 LVA0M O A-Link Negative LVDS Differential Data Output 66 VDDC I Digital Core Power 67 NC Not Connected 68 NC Not Connected 69 NC Not Connected 70 NC Not Connected 71 NC Not Connected 72 NC Not Connected 73 NC Not Connected 74 NC Not C
98 AVDD_MPLL 99 GPIO_P16/PWM2 100 NC I I/O MPLL Power General Purpose Input/Output; 4mA driving strength/ Pulse Width Modulation Output; 4mA driving strength Not connected 23 ViewSonic Corporation Confidential - Do Not Copy VA503b-2_VA503m-2
5. Adjustment Procedure 1. Key Function Description CONTROL KEY KEYS FUNCTION [AUTO] [2] By pressing [AUTO] key, “Auto Image Adjust” is performed [MENU] [1] By pressing [MENU] key, Main menu display [▼] [▲] A. When “MENU OSD” display, press these keys to change the contents of an adjustment item, or change an adjustment value B. When “MENU OSD” is un-display, press these keys to change brightness and contrast [POWER] Power on or power off the monitor 2.
Sharpness +/English French German Italian Spanish Finnish Japanese Simplified Chinese Traditional Chinese On/Off H Position (+ / -) V Position (+ / -) Language Select Setup Menu Resolution Notice OSD Position OSD Time Out OSD Background On/Off Memory Recall 3.
Deactivate Resolution Notice Menu Push button [2] under Resolution Notice OSD, select Disable ------- 3.5 Factory Mode Introduction When input the signal, press “power key” to turn off the monitor. Press” [▼] +[▲] +[ ] “at the same time so as to enter factory mode. After power on, press ‘’Menu[1]’’ key, you can see the Factory menu. INL-V7 V3 060620 Auto Color Color Temperature : Currently using panel model name : Currently using firmware version information.
6. EDID (Rewrite EDID data to EEPROM) If we need to rewrite the EEPROM data, please confirm the following steps. 1. Plug in VGA Cable; we can rewrite the EDID data to EEPROM by using “EDID Rewrite” program. 2. If the “EDID Rewrite” process finished, please pull out VGA cable and press ‘’2’’+’’▲’’ at the same time. 3. Pull out AC power cable or press power key to restart. 7. Upload firmware to MCU via VGA Cable 7.
(2). Select “Connect”, auto connect for ISP. (3). Select “Run”, start ISP. (4). When the picture show “Verify OK”, ISP finished.
8 After repair, to ensure the quality you should do the following test and adjustment Item Content Equipment Test OSD function 1.Signal is set as 1024 x 768 @60Hz 2. LCM button are from left to right, checking whether each single function key and compound function key can be worked. Chroma Signal Generator Contrast Check 1. Set input mode to 1024 x 768 @60Hz 2. Set Pattern to 32 gray shades 3. Set contrast to the max. The brightest 6~8 shades brightness cannot be distinguished.
VA503m/b Assembly Block PCBA PWR& Inv/B*1 Cable Power&I/F *1 Lamp wire TAPE*2 (SCREW PW,M3*5,Ni)*5 Chassis*1 INNOLUX Panel*1 (SCREW PW,M3*4,Ni)*4 ASSY PANEL*1 IF Board*1 Lvds Cable*1 (SCREW PW,M3*5,Ni)*1 (BOLT,#4-40*11.8,Ni)*2 PLATE BASE*1 Rubber Foot*6 BASE COVER*1 SCREW, P,T3*6, Zn*1 ASSY BASE*1 Keypad*1 Keypad Cable*1 ( Screw , P , cross.T.
VA503m/b DisAssembly Block PCBA PWR& Inv/B*1 Cable Power&I/F *1 Lamp wire TAPE*2 (SCREW PW,M3*5,Ni)*5 IF Board*1 Lvds Cable*1 (SCREW PW,M3*5,Ni)*1 (BOLT,#4-40*11.8,Ni)*2 PLANE BASE*1 Rubber Foot*6 BASE COVER*1 SCREW, P,T3*6, Zn*1 ASSY BASE*1 Chassis*1 INNOLUX Panel*1 (SCREW PW,M3*4,Ni)*4 ASSY PANEL*1 Keypad*1 Keypad Cable*1 ( Screw , P , cross.T.
5. Packing for Shipping and Disassembly Procedure 5.1 Packing for Shipping 5.1.1 Packing Procedure z Paste protection film to protect the monitor. (Figure 1) z Put the monitor in the PE bag and seal the bag with tape. (Figure 2) ZZZ z z z z Figure 1 Figure 2 Disassemble the base by pushing the button.(Figure 3) Put the cushions on the monitor. (Figure 4) Place the base into the hole of cushions. (Figure 5) Place the monitor into the carton and then put all the accessories into the carton.
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6. Troubleshooting Flow Chart 1. Common Acknowledge z z z z z z z z z If you change the interface board, be sure that the U102, U103, U104 and U105 these four components also changed to the new I/F board because there was program inside. If not, please re-write EDID and upload firmware into U104 via VGA Cable. If you adjust clock and phase, please do it at the condition of Windows shut down pattern. If you confirm the R.G.B. color is normal or not, please do it under 16-grey scalar pattern.
2. No Power & Power LED Off No power Check circuit if short Check primary rectifier voltage Check IC802, C805, T801 Check F801, P801, D801 Check pin3 of IC802 voltage about 1V Check R801, R805, R822, R823, R817 Check pin2 of IC802 voltage about 2V Check R803, R807, R824, R825 Check pin1 of IC802 voltage is 5.
3. DC output voltage is unstable Output Voltage Unstable Check Vbe of Q801 below 0.
4. Output power is unstable Unstable power Check sampling Circuit Check R810, R811, R818 Change R810, R811, R818 Check the C pin voltage of IC803 if 3V Check the R pin voltage of IC803 about 2.5V Change IC803 Check R809, R808, R814, D809 Check pin1 of IC802 voltage is 5.
5. Backlight can’t be turned on No raster? Yes LED Green? Yes Backlight can’t be turned on.
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7. White Screen W h ite S c r e e n OK L V D S C a b le R e in s e r t W o r k m a n s h ip NG OK C h a n g e L V D S C a b le L V D S C a b le N G NG C h e c k V L C D is 3 .3 V ? OK C h e c k L V D S s ig n a ls OK P a n e l F a il NG U 1 0 3 F a il OK NG C h e c k V c c 3 .
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7. Recommended Spare Parts List RECOMMENDED SPARE PARTS LIST (VA503b-2) ViewSonic Model Number: VS11357 Serial No. Prefix: QAE Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Rev: 1a Description PWRCORD 10A/250V BLACK 6FT SAA,H05W-F/3G (Australia) Accessories: PWRCORD 5A/250V BLK 6FT UK3Gx.75mm(SP60/ (Singapore) PWRCORD 10A/250V BLK 6FT CHINA.RVV 3Gx0. PWR CORD 10A/125V BLK 6FT UL/CSA,SVT 18x PWRCORD 7A/125V BLK 6FT CNS,VCTF 3Gx0.
BOM LIST (VA503b-2) ViewSonic Model Number: VS11357 Rev: 1a Serial No.
BOM LIST (VA503M-2) ViewSonic Model Number: VS11357 Rev: 1a Serial No.
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Exploded Diagrams and Exploded Parts List (VA503b) ViewSonic Corporation 50 Confidential - Do Not Copy VA503b-2_VA503m-2
EXPLODED PARTS LIST (VA503m-2) ViewSonic Model Number: VS11357 Rev: 1a Serial No. Prefix: QAD Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 A B C D E ViewSonic P/N C-00008015 C-00008014 PL-00008003 N/A B-00008005 B-00008004 N/A N/A N/A C-00008016 N/A B-00006750 CB-00006732 N/A N/A N/A N/A HW-00005266 HW-00005270 N/A Ref.
VA503m-3 PACKING PART LIST (VA503m-2 ) ViewSonic Model Number: VS11357 Rev: 1a Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ViewSonic P/N N/A N/A N/A P-00006739 CB-00008002 CB-00005254 A-00008005 P-00006741 C-00008014 A-00006733 P-00006738 P-00008008 P-00008009 N/A N/A N/A Ref.
VA503b-3 PACKING PART LIST (VA503b-2 ) ViewSonic Model Number: VS11357 Rev: 1a Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 ViewSonic P/N N/A N/A N/A P-00006739 CB-00005254 A-00006743 P-00006741 C-00006745 A-00006733 P-00006738 P-00008008 P-00006737 N/A N/A N/A Ref.
9. Block Diagram 1 OZ9938G Open Protection Brightness 1 Power Transformer LTV817 Feedback OVP 14V 3.3V Keypad Connector 24C04 Audio In Phone Jack TDA7496L XTAL 14.318MHz TSUM16AL 3.3 V VA503b/m Block Diagram Rectifier & Filter Circuit TOP245Y OPP/OCP Rectifier & Filter Circuit AC Line Filter Power TFT LCD Panel 15" MT150XN03 V0(Innolux) Lamp1 AP9971 2 AC Socket Keyboard LDO 3.3V-1.
10. Schematic Diagrams VCC3.3 VCC3.3 3 3,4 ON/OFF R104 C106 0.1/50V U101 LD1117AL-1.8V VCC3.3 4K7 DIMMER 4 VOL MUTE 4 4 C103 0.1/50V VCC1.8 4 + C104 100u/16V C105 0.1/50V C107 1u/16V/NC Q103 PMBT3906 0.1/50V 0.1/50V 0.1/50V 0.1/50V 0.1/50V 0.01/50V 0.01/50V C110 C111 C112 C113 C114 C101 100 220 4 4 4 4 4 ORANGE R101 GREEN ORANGE Q104 PMBT3906 1 C109 R111 R112 KEY_UP KEY_DOWN KEY_POWER KEY_AUTO KEY_MENU LED_GREEN 4 LED_ORANGE 4 VCC3.
CN103 DZ11AA1-H5W6-4F 11 1 6 2 7 3 8 4 9 5 10 12 13 14 R120 75 1% R121 75 1% 60Ω R116 56 C118 0.047/25V FB108 60Ω R117 56 C119 0.047/25V FB109 60Ω R118 56 C120 0.047/25V R119 470/NC C121 0.047/25V/NC R123 100 C122 0.047/25V R124 100 C123 0.047/25V R125 100 C124 0.
VCC3.3 RXECRXEC+ LVA3M LVA3P 55 54 RXE3RXE3+ PWM2/GPIO_P24 R153 0/NC R143 R149 R150 WP MDA MCL PANEL_ENABLE R151 4K7/NC FB105 600Ω C136 22u/16V VCC3.3 100 100 8 7 6 5 VCC WP SCL SDA A0 A1 A2 GND 1 2 3 4 ViewSonic Corporation Model Date VA503b-2_VA503m-2 + C149 0.1/50V PANEL_ENABLE 2 Confidential - Do Not Copy C132 0.1/50V VDDP VCC3.3 U105 AT24C04N 57 C131 0.1/50V VCC3.
1 3 LED_O LED_G GND MENU AUTO POWER DOWN UP LED901 LED G/Y 2 SW905 1 2 SW904 4 3 1 2 TACT-4.3 4 3 SW_TACT MENU AUTO SW903 1 2 4 3 SW_TACT POWER SW902 1 2 4 3 SW_TACT DOWN CN901 8P R/A 2.
C820 2200p/400V R802 10 R804 68 ZD802 P6KE200A-LF C805 82u/450V R803 510K R801 2M4 4 3 R805 2M4 2 R822 2M4 R825 470K ZD805 12V 9 3 + 1 3 C822 0.1/50V R827 10K R813 NC/1K R815 1K 2 Q801 NC/PMBT3904 1 R810 51K 1% R814 1K 1 3 5 D809 1N4148 C816 0.1/100V 3 1 + C819 47u/25V IC803 2 TL431 R819 NC/10K R818 3K3 1% C823 NC/0.1/50V 2 C817 0.1/50V PGND + C818 47u/25V CN801 90mm 8P P801 AC_SKT C824 VCC3.3V 1 2 3 4 5 6 7 8 3300p/400V ON/OFF BRIGHTNESS VOL MUTE C821 0.
+14V R502 680 + C501 220u/25V C502 2.2u/25V 3 R503 1K5 C503 0.1/50V C507 2.2u/25V PGND 16 2 VDDA DRV2 15 GNDA 14 3 TIMER 4 DIM CT 13 5 ISSEN SSTCMP 12 6 VSEN LCT 11 ENA 10 7 R515 NC C515 2.2u/25V 8 OVPT NC NC IC501 OZ9938G 9 R525 10 8 2 7 3 6 4 5 1 C508 NC 4 6 7 CN502 4200-D208 3 R516 604K 1% C511 0.047/25V C512 330p/50V C521 NC D502 BAV99 3 R510 3K9 1% C509 5p/3KV C513 6800p/50V C514 NC D503 BAV99 1 H 2 L R523 470 2 C517 0.
Layout guide : 1. Tie the I.C. pin 1,2,3,18,19,20 to ground with a large copper pour (open mask layer) VAROUT_L 5 GND GND GND GND GND GND GND 10u/25V 5K1 R701 + + 1K 7 R710 VAROUT_R + + R C707 470u/16V 1K 10 R709 SVR 0.1/50V 15 VS 14 4 3 2 1 C713 4700p/50V C712 2K R712 R711 R707 4700p/50V 2 Q701 PMBT3904 1 VOLUME OUTR L CN701 4P R/A 2.
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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.
