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All manuals and user guides at all-guides.com Acer AL1951 Service Guide...
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All manuals and user guides at all-guides.com 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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All manuals and user guides at all-guides.com 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.
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All manuals and user guides at all-guides.com 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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All manuals and user guides at all-guides.com 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.
All manuals and user guides at all-guides.com Table Of Contents Chapter 1 Monitor Features ……………………………………… Introduction ……………………………………… Electrical Requirements ……………………………………… LCD Monitor General Specification ……………………………………… LCD Panel Specification ……………………………………… Block Diagram ……………………………………… Main Board Diagram ……………………………………… Software Flow chart ……………………………………… Main Board Layout ………………………………………...
This will alleviate the growing health concerns. It is also a space saving design, allowing more desktop space, and comparing to the traditional CRT monitor, it consumes less power and gets less weight in addition MTBF target is 50k hours or more. Chart of AL1951 19" SEC Panel LTM190EX-L01...
All manuals and user guides at all-guides.com Electrical Requirements Standard Test Conditions All tests shall be performed under the following conditions, unless otherwise specified. Dark room Ambient light 40 cm for LCD performance, 20 cm for LCD failures Viewing distance Warm up time All specifications >30 minutes...
All manuals and user guides at all-guides.com LCD Monitor General Specification 19 “ active matrix color TFT LCD Panel type SEC LTM190EX – L01 376.32mm (H) × 301.056mm(V) Display size Normally white Display mode 0.294mm(H) × 0.294mm(V) Pixel pitch 1280 x (RGB) ×1024 Display dot 135 MHz Pixel clock...
All manuals and user guides at all-guides.com LCD Panel Specification LCD Panel Model (SAMSUNG LTM190EX- L01) Display Type active matrix color TFT LCD Resolution 1280x1024 pixels Display Dot 1280x (RGB) x 1024 Display Area 376.32mm(H) x 301.056mm(V) Pixel Pitch 0.294mm(H) x 0.294mm(V) Display Color 16.7M (true) Lamp Frequency...
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All manuals and user guides at all-guides.com ITEM Symbol Condition MIN. TYP. MAX. UNIT Contrast Ratio (Center of screen) Rising Response Time msec Falling Luminance of white cd/m (Center of screen) 0.610 0.640 0.670 0.299 0.329 0.359 0.270 0.300 0.330 Green 0.570 0.600...
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All manuals and user guides at all-guides.com Supported Timing VESA MODES Horizontal Vertical Nomina Sync Nomin Sync Nominal Polarity Polarity Pixel Freque Freq. Clock Mode Resolution Total +/- 1 (MHz) 0.5kHz 640x480@60Hz 800 x 525 31.469 59.940 25.175 640x480@72Hz 832 x 520 37.861 72.809 31.500...
All manuals and user guides at all-guides.com 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.
All manuals and user guides at all-guides.com 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.
All manuals and user guides at all-guides.com 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.
All manuals and user guides at all-guides.com Chapter 2 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) Fig 1 Fig2 3.
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All manuals and user guides at all-guides.com 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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All manuals and user guides at all-guides.com 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)
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All manuals and user guides at all-guides.com Fig 7 Fig 8...
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All manuals and user guides at all-guides.com Fig 9...
All manuals and user guides at all-guides.com Chapter 3 Troubleshooting This chapter provides troubleshooting information for the AL1951: 1. No power No power Press power key and look if the picture is normal Measure 12V input voltage Check the adapter...
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All manuals and user guides at all-guides.com 2. No picture (LED is orange) No picture X402 oscillate waveform Key is under control? is normal Replace X402 X401 oscillate waveform is normal Replace U402 Replace X401 Replace U401 Check if the sync signal from computer is output and video cable is connected normally Input the sync signal of computer,...
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All manuals and user guides at all-guides.com 3. Panel Power Circuit Measure Q703 base is high level? X402 oscillate waveform is normal Check Q703 and Q704 are Replace X402 broken or CN503 solder? Replace U402 Check Correspondent component. Replace U401 Replace PANEL...
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All manuals and user guides at all-guides.com 4. Keypad Board OSD is unstable or not working Connect Keypad Board Is Keypad board connecting normally Is Button Switch normally Replace Button Switch Is Keypad board normally Replace Keypad Board...
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All manuals and user guides at all-guides.com 5. Inverter Board No Backlight Check CN801 Pin1 =12V Check adapter Check ON/OFF signal Check Interface board Check U801 PIN3 voltage is normal? Check Q804,Q803,Q802 circuit Check U801 PIN18 triangular wave is normal Check C816, C821 Check U801 PIN11, 12, 19, 20 Check U801,Q801, Q805, Q806, Q807...
All manuals and user guides at all-guides.com 6.No Audio Mute and volume setting is ok? Reset mute and volume Check power supply of U601 is 12V? Check connecting is ok? Check input signal of U601is ok? Reconnect Check correspondent component Replace U601 Replace speaker Connector Information...
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All manuals and user guides at all-guides.com Chapter 4 The following figure shows the connector locations on the monitor board: 15 – Pin Color Display Signal Cable (D-sub) PIN NO. DESCRIPTION PI N NO. DESCRIPTION Green Logic Ground Blue Monitor Ground Monitor Ground DDC-Serial Data DDC-Return...
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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/).
All manuals and user guides at all-guides.com Exploded Diagram (Model: AL1951)
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All manuals and user guides at all-guides.com 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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All manuals and user guides at all-guides.com MAIN FRAME 15L6191 1 Panel 750LLS90EX1 Power board INPC1942SEA1 Main board CBPC980KS2AY 78G 322 3 L& Speakers 78G 322 3 R...
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All manuals and user guides at all-guides.com...
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All manuals and user guides at all-guides.com VCPU VCPU R409 C444 C431 RP401 RP402 1/16W 1/16W 1/16W 0.1uF 1/16W C432 22pF U402 X402 POWER EA/VP P0.0 ENTER P0.1 RIGHT XTAL1 P0.2 C433 20MHz LEFT P0.3 10uF/16V VCPU AUTO P0.4...