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SERVICE MANUAL 19” LCD Monitor f1905 Series THESE DOCUMENTS ARE FOR REPAIR SERVICE INFORMATION ONLY. EVERY REASONABLE EFFORT HAS BEEN MADE TO ENSURE THE ACCURACY OF THIS MANUAL; WE CANNOT GUARANTEE THE ACCURACY OF THIS INFORMATION AFTER THE DATE OF PUBLICATION AND DISCLAIMS RELIABILITY FOR CHANGES, ERRORS OR OMISSIONS.
HP f1905 Service Manual 1. Product Feature 48.3cm (19”) a-si TFT Active matrix LCD panel, 0.294mm dot pitch Scalar chipset: Genesis GM5321 Microprocessor controlled scan technology Both VGA analog and DVI-D digital signal video inputs supported 450:1 Typical Contrast Ratio and 250-nits typical Brightness...
HP f1905 Service Manual 3. Operation Instructions 3.1 General Instructions Press the power button to turn the monitor on or off. The other control buttons are located on the side of the front panel. By changing these settings, the picture can be adjusted to your personal performance.
HP f1905 Service Manual 3.3 Adjust the Picture Brightness Adjust the brightness. Contrast Adjust the contrast Adjust the: Auto Adjustment: Adjusts the main settings and produces a stable, centered image. H-Position: horizontal position of the screen image. Image Control V-Position: vertical position of the screen image.
HP f1905 Service Manual 4. Input/Output Specification 4.1 Input Signal Connector 4.1.1 Analog D-SUB Connector MNEMONIC SIGNAL MNEMONIC SIGNAL Red Video +5 V +5 V (from PC) Green Video Sync Ground Blue Video None (Reserved for Factory Use) None DDC Data...
HP f1905 Service Manual DVI-D digital connector layout 4.2 Factory Preset Display Modes Factory Pre-set Video Input Modes Horizontal Vertical Frequency Pre-set Pixel Format Frequency (kHz) (Hz) 640 x 480 31.5 60.0 640 x 480 37.9 72.0 640 x 480 37.5...
HP f1905 Service Manual 4.3 Power Supply Requirements PARAMETER RANGE AC Input Voltage 90 to 265V AC Input Frequency 47 to 63 Hz Inrush Current 50A MAX AT 220VAC and 30A AT 120VAC Leakage Current 5 mA MAX at 120VAC Power consumption <70W...
HP f1905 Service Manual 6.2 Software Flow Chart MCU initialize. Is the eeprom blank? Program the eeprom by default values. Get the PWM value of brightness from eeprom. Check the pin PANEL1 and PANEL2 to tell which panel to get with it.
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HP f1905 Service Manual 1.8V_CVDD Clos e to re s pe ctive pow e r Pins +1.8V FB201 120 OHM C202 C203 C204 C205 C206 C207 C208 C201 1.8V_AVDD 10uF/50V 0.1uF 0.1uF 0.1uF 0.1uF 0.1uF 0.1uF 0.1uF 1.8V_DVI 1.8V_PLL 1.8V_CVDD 3.3V_LVDS...
HP f1905 Service Manual 9. Maintainability 9.1 Equipments and Tools Requirement 1.) Multi-meter. 2.) Oscilloscope. 3.) Pattern Generator. 4.) DDC Tool with an IBM Compatible Computer. 5.) Alignment Tool. 6.) LCD Color Analyzer. 7.) Service Manual. 8.) User Manual.
HP f1905 Service Manual 9.2 Trouble Shooting 9.2.1 Main Board No power No power Press power key and look if the picture is normal Please reinsert and make sure the AC of 100-240 is normal Reinsert or check the power section Measure U301 PIN2=1.8V?
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HP f1905 Service Manual No picture (LED is orange) No picture 1.Check power section Measure U301 PIN2=1.8V? Measure U302 PIN2=3.3V? 2.Replace U301, U302 X201 oscillate waveforms are normal Replace X201 Check if the sync signal from computer is output and video...
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HP f1905 Service Manual Panel Power Circuit Measure Q402 base is high level? X201 oscillate waveforms are normal Check Q402 and Q203 Replace X201 are broken or CN401 Replace U201 Check Correspondent component. Replace PANEL...
HP f1905 Service Manual 9.2.2 Power Board No Power No power Check AC line volt 110V or 220V Check AC line Check the voltage of C904(+) Check F901, bridge rectified circuit Check start voltage for the pin3 of IC901 Check R912, R916, R918, IC901...
HP f1905 Service Manual 9.2.3 Keypad Board OSD is unstable or not working Is Keypad board connecting normally Connect Keypad Board Is Button Switch normally Replace Button Switch Replace Keypad Board Is Keypad board normally Check main board...
C. SRGB SRG color temp. parameter is x = 313±10, y = 329 ±10, Y = 210 ±10 cd/m 3. Into factory mode of HP L1902 A. Press MENU button during 2 seconds along with press Power button will activate the factory mode, then MCU will do AUTO LEVEL automatically.
HP f1905 Service Manual 7. Repeat above procedure ( item 4,5,6) until chroma 7120 RGB value meet the tolerance =100±2 B. Adjust SGB color-temperature 1. Switch the chroma-7120 to RGB-Mode (with press “MODE” button ) 2. Switch the MEM .Channel to Channel 4( with up or down arrow on chroma 7120 ) 3.
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HP f1905 Service Manual 12. BOM T980KAVDKHHPA CBPC980KAVHP CONVERSION BOARD KEPC980KB4 KEY BOARD PWPC1942AUH5 POWER BOARD 11L6049 2 TIE MOUNT(S) 12G 423 1 BUCKET BUMPER 15L8127 1 MAIN FRAME 23L3178690 6A LOGO 33L4802 PC L BASE COVER 34L1471APC B BEZEL...
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HP f1905 Service Manual 705L980KB34082 19" BACK COVER ASS'Y 705L980KP34003 19" STAND ASS'Y 750LLU90N04 LCD PANEL M190EN04 V2 B AIC980KAVHP MAIN BOARD 40G 45762412B CBPC LABEL 40L 457624 1B CPU LABEL C201 67L305V100 7N GP EL105C (SHORT) C209 67L305V100 7N GP...
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HP f1905 Service Manual ZD107 93L 39S 34 T UDZS5.6B PW1942AUH5SMT POWER BOARD FOR SMT 40L 45762420A ID LABEL 1.02 705L 980 56 03 CN901 ASS'Y 705L 980 57 07 Q901 ASS'Y 705L 980 87 04 CN901 ASS'Y 705L 980 93 06...
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HP f1905 Service Manual L901 73L 174 53 L GP CHOKE L902 73L 174 40 LS LINE FILTER L903 73L 253151 L CHOKE COIL 45VH L905 73L 253 91 L CHOKE BY LI TA L906 73L 253 91 L CHOKE BY LI TA...
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HP f1905 Service Manual C910 65L0603104 22 CAP:CER 0.1UF 10% 25V S C911 65L0603104 22 CAP:CER 0.1UF 10% 25V S C919 65L0805104 32 CHIP 0.1UF 50V X7R C923 65L0603104 22 CAP:CER 0.1UF 10% 25V S C924 65L0805471 21 CHIP 470PF 25V NPO...
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HP f1905 Service Manual T980KCVDKHHPA CBPC980KCVHP CONVERSION BOARD KEPC980KB4 KEY BOARD PWPC1942CPH3 POWER BOARD 11L6049 2 TIE MOUNT(S) 12G 423 1 BUCKET BUMPER 15L8127 1 MAIN FRAME 23L3178690 6A LOGO 33L4802 PC L BASE COVER 34L1471APC B BEZEL 34L1473APD 1B...
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HP f1905 Service Manual 705L980KB34082 19" BACK COVER ASS'Y 705L980KP34003 19" STAND ASS'Y 750LLC90A03 CPT 19" EA03 PANEL AIC980KCVHP MAIN BAORD 40L 457624 1B CPU LABEL 40L 45762412B CBPC LABEL 67L305V100 7N C201 EL105C (SHORT) 67L305V100 7N C209 EL105C (SHORT)
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HP f1905 Service Manual 14.318MHzHC-49U 715L1370 C H MAIN BOARD C101 65L0805105 22 CHIP 1UF 25V X7R 0805 C103 65L0603473 32 CHIP 0.047UF 50V X7R C104 65L0603473 32 CHIP 0.047UF 50V X7R C106 65L0603473 32 CHIP 0.047UF 50V X7R C107 65L0603473 32 CHIP 0.047UF 50V X7R...