1 Precautio 1-1 Safety Precautions WARNINGS Inspect all protective devices such as nonmetallic For continued safety, do not attempt to modify the control knobs, insulating materials, cabinet backs, circuit board. adjustment and compartment covers or shields, isolation resistor-capacitor networks, mechanical Disconnect the AC power before servicing.
1 Precautions 1-2 Servicing Precautions WARNING1: First read the “Safety Precautions” section of this manual. If unforeseen circumstances create conflict between the servicing precautions and safety precautions, always follow the safety precautions. WARNING2: A high voltage VR replaced in the wrong direction may cause excessive X-ray emissions.
2 Product Specifications 2-2 Timing Chart This section of the service manual describes the timing that the computer industry recognizes as standard for computer-generated video signals. Table 2-1. Timing Chart (17”) Mode VESA MAC. VGA2/70 Hz VGA3/60 Hz 640/85 Hz 800/85 Hz 1024/75 Hz 1024/85 Hz...
Page 6
2 Product Specifications Table 2-2. Timing Chart (19”) Mode VESA MAC. VGA2/70Hz VGA3/60Hz 640/85 Hz 800/85 Hz 1024/85 Hz 1024/100 Hz 1280/75 Hz 1280/85 Hz 1600/75 Hz 1152/75 Hz 720 x 400 640 x 480 640 x 480 800 x 600 1024 x 768 1024 x 768 1280 x 1024...
3 Disassembly and Reassembly This section of the service manual describes the disassembly and reassembly procedures for the CSE78**T/CSE98**T monitors. WARNING: This monitor contains electrostatically sensitive devices. Use caution when handling these components. 3-1 Disassembly Cautions:1. Disconnect the monitor from the power source before disassembly. 2.
Page 9
3 Disassembly and Reassembly 3-1-8 Removing the Video PCB Assembly 3-1-10 Removing the Main PCB Rear Shield and Video PCB 1. Remove 7 screws on the main PCB. 1. Remove the 8 screws on the PCB Assembly. 2. Pull the Main PCB towards you and carefully lift out the main PCB and placet it on a flat, 2.
4 Alignment and Adjustments This section of the service manual explains how to make permanent adjustments to the monitor. Direction is given for adjustment using the monitor Interface Board Ver. 2.0 and software (SoftJig). 4-1 Adjustment Conditions Caution: Changes made without the SoftJig are saved only to the user mode settings. As such, the settings are not permanently stored and may be inadvertently deleted by the user.
Page 11
5. Signal generator, or Computer with a video board that uses the ET-4000 chipset (strongly recommended if using Samsung DM 200 software) and that displays: 1280 x 1024 @ 85 Hz, or 1600 x 1200 Figure 4-1. Setup 1, With Signal Generator @ 85 Hz (maximum).
Page 12
4 Alignment and Adjustments 4-2 Display Control Adjustments 4-2-1 Centering 4-2-1 (d) VERTICAL POSITION ADJUSTMENT Centering means to position the center point of CONDITIONS the display in the middle of the display area. Scanning frequency: 68 kHz/85 Hz Horizontal size and position and vertical size and Display image: Crosshatch pattern position control the centering of the display.
Page 13
4 Alignment and Adjustments 4-2-2 (b) VERTICAL LINEARITY ADJUSTMENT CONDITIONS Scanning frequency: 68 kHz/85 Hz Display image: Crosshatch pattern Brightness: Cut-off 5 mm Contrast: Maximum Figure 4-6. Parallelogram To adjust the Vertical Linearity, refer to Tables 4-1 and 4-2 for the tolerance range. 4-2-6 Side Pincushion Adjustment Click on the <<...
4 Alignment and Adjustments 4-3 Color Adjustments 4-3-1 Color Coordinates (Temperature) 4-3-2 (b) G-GAIN ADJUSTMENT Color temperature is a measurement of the 1/3H-1/2H radiant energy transmitted by a color. For FRONT BEZEL OPENING computer monitors, the color temperature refers to the radiant energy transmitted by white. Color BACK RASTER 1/3V-1/2V coordinates are the X and Y coordinates on the...
Page 15
4 Alignment and Adjustments 4-3-2 (d) WHITE BALANCE ADJUSTMENT VERIFICATION 4-3-3 (c) WHITE BALANCE ADJUSTMENT CONDITIONS CONDITIONS Scanning frequency: 68 kHz/85 Hz Scanning frequency: 68 kHz/85 Hz Display image: Back raster pattern Display image: Full white pattern X-Y Coordinates: x = 0.283 ± 0.02, Brightness: Cut-off y = 0.298 ±...
Page 16
4 Alignment and Adjustments 4-3-4 (d) WHITE BALANCE ADJUSTMENT VERIFICATION CONDITIONS Orientation: Monitor facing east Refer to the procedure for 9300K, section 4-3-2 (d). Scanning frequency: 68 kHz/85 Hz Display image: White flat field 4-3-5 Luminance Uniformity Check Luminance: Cut off point at the center of the display area Luminance is considered uniform only if the ratio of lowest to highest brightness areas on the screen...
Page 17
4 Alignment and Adjustments Memo CSE78**T/CSE98**T...
5 Troubleshooting 5-1 Parts Level Troubleshooting Notes: 1. If a picture does not appear, fully rotate the brightness and contrast controls clockwise and reinspect. 2. Check the following circuits. • No raster appears: Power circuit, Horizontal output circuit, H/V control circuit, and H/V output circuit. •...
Page 19
5 Troubleshooting 5-1-2 DPMS Failure Check signal source H/V sync video level. Make No H/V sync (power off mode) LED blinks Check IC201 Pin 31. +12 V line off Check IC201 Pin 1. Check IC201 Pin 2. Q632 Base driving voltage exists? Check and replace Q632.
Page 20
5 Troubleshooting 5-1-3 H_Deflection Failure WAVEFORMS 1. Check R401, +12 V line. IC401 Pin 6 waveform is right? 2. Check IC401 Pins 7~6, 6~5. 10.96 V (IC401, #6) 3. Replace IC401. Q405 source waveform Check Q405, R422, R423, D406 is right? and D415, +220 V line.
Page 21
5 Troubleshooting 5-1-4 S Correction Failure Check S1 ~ S5 signal. S1~S5 signals are right at each Check and replace IC201. frequency block? Check and replace Q409~Q413, C430, C431, C433, C434, C435, C437 and C441. 5-1-5 H_Lin. Failure IC201 Pin 4 voltage varies with Replace IC201.
Page 22
5 Troubleshooting 5-1-7 Abnormal H_Size WAVEFORMS IC201 Pin 42 output duty varies Check and replace IC201. with different B+ offset DAC Check some parts IC201 Pin 42, 29.8 V (T402, #8) values? IC251 Pin 28 and IC401 Pin 2. T402 Pin 8 waveform is right? Check and replace T402.
Page 23
5 Troubleshooting 5-1-10 Tilt Failure Check tilt connector connection IC201 Pin 6 output duty varies Check and replace IC201. with different DAC values? IC403 Pin 8 output varies with Check and replace IC403. different DAC values? Check and replace CRT. 5-1-11 V Deflection Failure ±14 V line is on? Refer to 7-1-1 No Power Supply...
Page 24
5 Troubleshooting 5-1-12 V Size or Pos. Variation Failure IC251 Pin 23 output varies with Check some parts around IC301. different DAC values? Check bias voltage. Check and replace IC251 and IC301. 5-1-13 High Voltage Failure WAVEFORMS +220 V is on Q502 collector? Check and replace Q502.
Page 25
5 Troubleshooting 5-1-14 ABL Failure Input full white pattern to monitor. IC5 Pin 12 input exists and Check and replace IC5. varies with different patterns? Check CN103. T502 Pin 8 output exists? Check and replace T502. IC201 Pin 3 output exists and Check and replace IC201.
Page 26
5 Troubleshooting 5-1-16 No Video Check signal cable and connection. IC5 Pins 5, 8 and 10 inputs Check IC1. are right? IC5 Pins 21, 24 and 26 Check I C bus and +12 V line. outputs are right? IC03 Pins 4, 6 and 14 outputs Check +12 V line.
Page 27
5 Troubleshooting 5-1-17 Micom Failure WAVEFORMS IC201 Pin 25 input is right? Check IC606. 3.42 V (IC201, #33) IC201 Pins 32 and 33 inputs Check X201, C213 and C214. are right? CH1 P-P = 3.42 V CH1 RMS = 2.500 V 3.16 V (IC201, #32) IC201 Pin 40 input is right? Check IC202.
Page 28
5 Troubleshooting 5-1-18 OSD Failure Check CN202 and connector Ass’y. IC04 Pin 17 input is right? Check and replace Q303 and D304. IC04 Pin 6 input is right? Check and replace Q101. IC04 Pins 7 and 8 inputs are right? Check IC201 Pins 29 and 30.
Page 29
5 Troubleshooting 5-1-19 User Control Failure Check connector Ass’y. IC201 Pins 11 and 12 inputs are Check and replace function key. right at each function. Check and replace IC201. Done 5-1-20 Degaussing Failure Check degaussing connector. RL601 operation is right? Check D-Coil, Pos 601.
5 Troubleshooting 5-2 General Troubleshooting 5-2-1 No Picture LED blinks? 5-2-2 Shut down LED is green color? LED is Amber color? Check signal cable. Check G2 voltage, high voltage, After restart monitor LED don’t R, G, B cathode voltage. come on, repair power circuit. 5-2-2 Shut Down Blinking LED’s? Check power supply.
Page 31
5 Troubleshooting 5-2-3 Missing Color Are proper Video levels on CN101 (D-Sub) Pins 1, 2 and 3, Check signal generator and cathode. R-BNC, G-BNC and B-BNC. Are proper AC voltage on all Refer to 5-1-16 No Video. cathodes? Check IC5 Pins 15, 16 and 17. Are proper DC voltage on all Check QR01, QR02, QG01, cathodes?
Page 32
5 Troubleshooting 5-2-4 Visible Retrace Check white balance adjustment. Is G2 voltage right? Check G2 control volume and FBT. Is blank pulse on Pin 19 of IC5 Check Q102, CN103 and T402 Pin 8. on Video board? Is blank pedestal on Check IC5 and related components.
Page 33
5 Troubleshooting 5-2-5 Unsynchronized Image Check input signals Pins 2, 13 and 14 of CN101 and G-BNC. Are signals right? Check Video cable. Signals at Pins 1, 13 and 15 of Check IC6 on Video board. CN102 are right? Signals at CN201 Pin 1, CN204 Check wire dressing and connections.
Page 34
5 Troubleshooting 5-2-6 Misconvergence Try readjusting convergence. Is the convergence now Done within spec? Readjust convergence. Is the convergence now Done within spec? Change CRT and readjust convergence. Done CSE78**T/CSE98**T 5-17...
Page 35
5 Troubleshooting 5-2-7 Poor Focus Adjust focus VR. Aging monitor and check for focus Improved focus? change. Check focus leads from FBT to CRT Socket. Check the CRT Socket. Refer to 5-1-15 Dynamic Is dynamic focus circuit right? Focus Failure. Replace the CRT and verify focus.
Page 62
7 Electrical Parts List 7-4 Different Parts List 7-4-1 for Different Model Model CSE7839 CSE780B CSE7829 CSE788B CSE9839 CSE980B CSE9829 CSE988B Loc. CN206 BH39-40361R BH39-40361R – – BH39-40361R BH39-40361R BH39-40361R BH39-40361R CN203 3711-003851 3711-003851 – – 3711-003851 3711-003851 3711-003851 3711-003851 –...
Page 64
7 Electrical Parts List 7-5 A Classified Table of Model Files & Model Names According to Basic Models BASIC MODEL COUNTRY MODEL FILE MODEL NAME KOREA SE780SK SE780B SDD KOREA CSE780B EXPORT SE780SE SE780B BAS SDD KOREA SE788SK SE788B SDD KOREA CSE788B EXPORT SE788SE...