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Service Guide Version and Revision Version Release Date Revision Mar.-12 - 2005 Original release...
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Printed in Taiwan. Disclaimer The information in this guide is subject to change without notice. Acer Incorporated makes no representations or warranties, either expressed or implied, with respect to the contents hereof and specifically disclaims any warranties of merchantability or fitness for any particular purpose.
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ACER-AUTHORIZED SERVICE PROVIDERS, your Acer office may have a DIFFERENT part number code to those given in the FRU list of this printed Service Guide. You MUST use the list provided by your regional Acer office to order FRU parts for repair and service of customer machines.
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Warning: (For FCC Certified Models) Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy, and if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
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Precautions Do not use the monitor near water, e.g. near a bathtub, washbowl, kitchen sink, laundry tub, swimming pool or in a wet basement. Do not place the monitor on an unstable trolley, stand, or table. If the monitor falls, it can injure a person and cause serious damage to the appliance.
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Special Notes On LCD Monitors The following symptoms are normal with LCD monitor and do not indicate a problem. Notes Due to the nature of the fluorescent light, the screen may flicker during initial use. Turn off the Power Switch and then turn it on again to make sure the flicker disappears. You may find slightly uneven brightness on the screen depending on the desktop pattern you use.
Signal Interface Sync Type Color Temp User Adjust Headphone Jack Microphone Jack USB Hub Tilt / Swivel Chart of AL1951 Panel Separate / Compatible 1.5W + 1.5W (Rated power) Speaker 3.5mm stereo phone jack, Chapter 1 19" SEC LTM190EX-L01...
Electrical Requirements Standard Test Conditions All tests shall be performed under the following conditions, unless otherwise specified. Ambient light Viewing distance Warm up time All specifications Fully functional Measuring equipment Control settings User brightness control User contrast control User red/white balance, Green/white balance and Blue/white balance control Power input...
LCD Monitor General Specification Panel type Display size Display mode Pixel pitch Display dot Pixel clock Contrast ratio Brightness Response time (Tr/Tf) Display color Viewing angle Pc interface Signal connector Interface frequency Plug & play Power Input voltage Total output power 19 “...
LCD Panel Specification LCD Panel Model (SAMSUNG LTM190EX- L01) Display Type Resolution Display Dot Display Area Pixel Pitch Display Color Lamp Frequency Lamp Current Weight Optical Specifications IL = 6.5mArms Ta = 25 ± 2°C active matrix color TFT LCD 1280x1024 pixels 1280x (RGB) x 1024 376.32mm(H) x 301.056mm(V)
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ITEM Contrast Ratio (Center of screen) Response Time Luminance of white (Center of screen) Green Color Chromaticity (CIE 1931) White Green Color Chromaticity (CIE 1976) White Color Gray scale White linearity Viewing Angle Brightness Uniformity (9 Points) Cross Modulation Flicker Symbol Condition MIN.
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Supported Timing Mode Resolution 640x480@60Hz 640x480@72Hz 640x480@75Hz 800x600@56Hz 800x600@60Hz SVGA 800x600@72Hz 800x600@75Hz 1024x768@60Hz 1024x768@70Hz 1024x768@75Hz 1152x864@75Hz 1280x1024@60H SXGA 1280x1024@75H 720x400@70Hz 640x350@70Hz 1024x768@72Hz 640x480@67Hz SVGA 832x624@75Hz 1024x768@60H 1024x768@75H VESA MODES Horizontal Nomina Freque Total 0.5kHz 800 x 525 31.469 832 x 520 37.861 840 x 500 37.500...
Monitor Block Diagram The LCD MONITOR will contain a main board (include: keypad board and audio board), an inverter board, adapter which house the flat panel control logic, brightness control logic and DDC. The Inverter board will drive the backlight of panel. The adapter will provide the 12V DC-power to inverter/power board and main board.
Software Flow Chart 1) MCU initialize. 2) Is the eeprom blank? 3) Program the eeprom by default values. 4) Get the PWM value of brightness from eeprom. Check the pin PANEL1 and PANEL2 to tell which panel to get with it. 5) Is the power key pressed? 6) Clear all global flags.
Logo When the monitor is power on, the LOGO will be showed in the center, and disappear slowly. How To Optimize The DOS-Mode Plug And Play Plug & Play DDC1/2B Feature This monitor is equipped with VESA DDC1/2B capabilities according to the VESA DDC STANDARD.
Machine Disassembly This chapter contains step-by-step procedures on how to assemble the monitor for maintenance. Disassembly Procedure 1. Remove two screws to release back cover. (Fig 1). 2. Remove the base stand (Fig 2) 3. Remove four screws to release front bezel. (Fig 3) 4.
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Fig 3 Fig 4 5. Remove eleven screws to release top cover and bottom cover. (Fig 5) 6. Remove the main board. (Fig 6)
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Fig 5 Fig 6 7.Remove six clamps to release shield and the main board. (Fig 7) 8.Remove the main frame. (Fig 8) 9.Remove the inverter board. (Fig 9)
Troubleshooting This chapter provides troubleshooting information for the AL1951: 1. No power Press power key and look if the picture is normal Measure 12V input voltage Measure U702 PIN2=5V? X402 oscillate waveform is normal No power Replace X402 Replace U402...
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2. No picture (LED is orange) No picture Key is under control? X401 oscillate waveform is normal Check if the sync signal from computer is output and video cable is connected normally Replace U401 Replace X401 Input the sync signal of computer, or change the cable X402 oscillate waveform is normal...
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3. Panel Power Circuit Measure Q703 base is high level? Check Q703 and Q704 are broken or CN503 solder? Check Correspondent component. Replace PANEL X402 oscillate waveform is normal Replace X402 Replace U402 Replace U401...
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4. Keypad Board OSD is unstable or not working Is Keypad board connecting normally Is Button Switch normally Is Keypad board normally Connect Keypad Board Replace Button Switch Replace Keypad Board...
6.No Audio Mute and volume setting is ok? Check power supply of U601 is 12V? Check input signal of U601is ok? Replace U601 Replace speaker Connector Information Reset mute and volume Check connecting is ok? Reconnect Check correspondent component...
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The following figure shows the connector locations on the monitor board: PIN NO. PIN NO. DESCRIPTION TMDS Data2+ TMDS Data 2/4 Shield TMDS Data4+ Analogue Vertical Sync TMDS Data1+ TMDS Data 1/3 Shield 15 – Pin Color Display Signal Cable (D-sub) DESCRIPTION Green Blue...
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FRU (Field Replaceable Unit) List This chapter gives you the FRU (Field Replaceable Unit) listing in global configurations of AL1951.Refer to this chapter whenever ordering for parts to repair or for RMA (Return Merchandise Authorization). NOTE: Please note WHEN ORDERING FRU PARTS, that you should check the most up-to-date information available on your regional web or channel (http://aicsl.acer.com.tw/spl/).
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Part List Item Picture Description Part No. 33G4841 QT L Hinge cover 33G4843 QT L Bezel 34G1541AQW B Back cover 34G1542 QT B SHIELDING 85L6117 1...
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MAIN FRAME 15L6191 1 Panel 750LLS90EX1 Power board INPC1942SEA1 Main board CBPC980KS2AY 78G 322 3 L& Speakers 78G 322 3 R...