Service Manual XGA COLOR MONITOR Model : 715B DAEWOO ELECTRONICS CO., LTD. http : //svc.dwe.co.
CONTENTS SAFETY PRECAUTIONS 1 GENERAL SAFETY INFORMATION 2 SERVICING PRECAUTIONS 3 TECHNICAL INFORMATION 6 GENERAL INFORMATION 7 PIN CONNECTOR 8 CAUTIONS FOR ADJUSTMENT AND REPAIR 8 OPERATION AND ADJUSTMENT 9 ALIGNMENT PROCEDURE 13 TROUBLESHOOTING HINTS 15 BLOCK DIAGRAM 31 PCB LAYOUT 32 SCHEMATIC DIAGRAM 35 EXPLODED VIEW & MECHANICAL PARTS LIST 36 INFORMATION OF PART DESCRIPTION 37 ELECTRICAL PARTS LIST 38
SAFETY PRECAUTIONS CAUTION: No modifications of any circuits should be attempted. Service work should be performed only after you are thoroughly familiar with all of the following safety checks and servicing guidelines. ◆ Safety Check Care should be taken while servicing this analog color display because of the high voltages used in the deflection circuits. These voltages are exposed in such areas as the associated flyback and yoke circuits.
GENERAL SAFETY INFORMATION ◆ Terms in the manual CAUTION Statements identify conditions or practices that could result in damage to the equipment or other property. WARNING Statements identify conditions or practices that could result in personal injury or loss of life. ◆ Terms as marked on equipment CAUTION Statements indicate a personal injury hazard not immediately accessible as one reads the marking or a hazard which is properly included on the equipment itself.
SERVICING PRECAUTIONS CAUTION: Before servicing instruments covered by this service manual, its supplements, and addendum, please read and follow the SAFETY PRECAUTIONS of this manual. NOTE: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions on page 1 of this manual, always follow the safety precautions. Remember: Safety First. ◆ General Servicing Precautions 1. Always unplug the AC power cord from the AC power source before: a.
◆ Electrostatically Sensitive (ES) Devices Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components are commonly called Electrostatically Sensitive (ES) Devices. The typical examples of ES devices are integrated circuits, some field-effect transistors, and semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity. 1.
FIGURE 1. USE SOLDERING IRON TO PRY LEADS ◆ IC Removal/Replacement Some utilized chassis circuit boards have slotted (oblong) holes through which the IC leads are inserted and then bent flat against the circuit foil. When holes are slotted, the following technique should be used to remove and replace the IC. When working with boards using the familiar round hole, use the standard technique as outlined in paragraphs 5 on the page under the title of general soldering guidelines. ◆ Removal 1.
◆ Power IC, Transistor or Devices Removal/Replacement 1. Heat and remove all solders from the device leads. 2. Remove the heatsink mounting screw (if applicable). 3. Carefully remove the device from the circuit board. 4. Insert new device in circuit board. 5. Solder each device lead and then clip off excess lead. 6. Replace heatsink. ◆ Diode Removal/Replacement 1. Remove defective diode by clipping its leads as close as possible to diode body. 2.
GENERAL INFORMATION This color monitor automatically scans all horizontal frequencies from 30KHz to 70KHz, and all vertical frequencies from 50Hz to 160Hz. This color monitor supports IBM PC, PC/XT, PC/AT, personal System/2 (PS/2), Apple Macintosh, and compatible users crisp text and vivid color graphics display when using the following graphics adapters : (VGA, 8514/A, Super VGA, VESA and XGA and Apple Macintosh Video Card).
PIN CONNECTOR Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Signal 1 Red Green Blue GND GND GND - Red GND - Green GND - Blue +5Vdc GND - H.Sync GND - V.Sync Bi-directional Data (SDA) Horizontal Sync Vertical Sync (VCLK) Data Clock (SCL) 6 10 15 Arrangement of 15-pin D-sub connector CAUTIONS FOR ADJUSTMENT AND REPAIR • Degaussing is always required when adjusting purity or convergence. • The white balance adjustment has been done by a color analyzer in factroy.
OPERATION AND ADJUSTMENT Control Panel SELECT ADJUST MENU MENU • Launch OSD(On-Screen Display) MENU window. • Select a sub Menu & function. • • • Move a sub Menu & function. • • • Move a sub Menu & function. SELECT Increase the value of any selected function. Adjust the contrast directly when there is no OSD. Decrease the value of any selected function. Adjust the brightness directly when there is no OSD.
Key Process MENU SELECT MENU MENU MENU OSD OFF • When you choose the icon on the OSD window, you can exit the OSD screen.
OSD Functions ICON CONTROL FUNCTIONS H. POSITION Adjust the position of the display horizontally (left or right). V. POSITION Adjust the position of the display vertically (up or down). H.SIZE Adjust the display width (horizontal size). V.SIZE Adjust the display height (vertical size). V. LINEARITY Adjust the vertical linearity. H. LINEARITY Adjust the horizontal linearity. PINCUSHION Adjust the left and right margins for more convex or more concave margins.
ICON CONTROL FUNCTIONS COLOR TEMP Choose different preset color temperatures or set your own customized color parameters. RED GAIN Adjust the red gain. GREEN GAIN Adjust the green gain. BLUE GAIN Adjust the blue gain. RED BIAS Adjust the red bias. GREEN BIAS Adjust the green bias. BLUE BIAS Adjust the blue bias. LANGUAGE Select language for OSD (5 languages). DEGAUSS Degaussing keeps the monitor free from unwanted magnetism that can result in color impurity.
ALIGNMENT PROCEDURE ◆ Standard Adjustment Conditions 1. Power source voltage : AC 120V, 60Hz/AC 220V, 50Hz. 2. Aging : Take at least 20 minutes warm-up time. 3. Signals. Video : Analog 0.7Vpp 75Ω terminal positive polarity Synchronizing : TTL Level Negative/Positive Separate/Composite Deflection frequency Horizontal Frequency : 30KHz - 70KHz Vertical Frequency : 50Hz - 160Hz ◆ Pre-Adjustment 1. High Voltage Adjustment Adjust 25.
(h) Select the R, G, B gain on the OSD menu and adjust the +/– key to get the color coordinates in X=0.281±0.02, Y=0.311±0.02. (i) Adjust the sub contrast (ABL) control to get the screen luminosity to 30.0 Ft/L. 6. Static Convergence Adjustment (a) Apply a magenta cross hatch pattern on display. (b) Adjust the focus from the best over all focus on the display. Also adjust the brightness to the desired condition.
TROUBLESHOOTING HINTS 1.
2. No Raster No Raster Is CRT heater red-hot? Is Heater Voltage (CRT PWB) about 6V? No Yes Yes Trouble in CRT No Trouble in power supply circuit Turn the Brightness & Contrast control to set Maximum Refer to trouble in power supply unit.
3. A Missing Color One color is missing Is input signal normal? No Check video signal cable or video card. No Trouble in IC801 or its ambient circuit No Is video output IC802 waveform normal? 0.
4. Abnormal OSD Font Abnormal OSD Font Is menu key selected? Is OSD Font exist? * If menu key selected. Is Heater Voltage about 6V? No Yes Yes One color is missing Troubie in IC803 or its ambient circuit Yes Is the output of IC803 (pin 12,13, 14) normal? No Trouble in IC803 and its ambient circuit Yes Refer to Missing Color 18 No Trouble in Heater voltage line. Refer to trouble in P.S.
5. Horizontal Output Circuit Trouble in Horizontal output circuit (No Raster) Is the B+line voltage over 175V? No Trouble in 175V line. Yes Is the H-out waveform of IC501 normal? 11V 0V No Trouble in IC501 Yes Is the Gate wave form of Q553 normal? 10V 0V No Trouble in Q551, Q552 Yes Is the Drain waveform of Q553 normal? 66V Yes Trouble in Q554 and its ambient circuit.
6. Unstable Picture 6-1. Horizontal Unstable picture Is H.Sync input pin of IC501 correct? No Yes Trouble in IC501 20 Check H.Sync Out of Micom or its ambient circuits.
6-2. Vertical Unstable or Abnormal picture Is – 13V DC line correct? No Check PWR – 13V ambient circuit. Yes Check V.DY and ambient circuit. Yes Check the IC401 or ambient circuit. Yes 45Vp-p Is the output waveform of IC401 (pin 5) normal? No Is the output pulse of IC501 (pin 4) normal? No Trouble in V.Sync line or IC501 failure.
7.
7-1. Dynamic Focus FVH FVV ORION * Check after adjusting the static focus finely by VR in FBT Focus is poor : 300V 150V DF waveform FVH FVV Is the waveform of the DF pin in FBT correct? Yes 1. Check the CRT socket or connector wire 2. Trouble in FBT or CRT No 1. Check the waveform of the pin 4 of FBT. 2. Check D705 No 1. Check the 12V DC line. 2.
8. Convergence Poor convergence Is convergence on the center area bad? Yes Adjust static convergence Refer to Adjustment procedure of convergence No Is convergence on the fringe area bad? Yes Adjust D.
9. Abnormal Picture 9-1. Horizontal Size Abnormal H.Size Is the HV 25.
9-2. Vertical Size Abnormal V.Size Is changeable the DC voltage of IC401 pin 1? No Is the 3.5Vdc of pin 4 of the IC501? Yes Trouble V.OSC/ Deflection Circuit No Check the IC501 and its ambient circuit Refer to V.
10. High Voltage Output Circuit Trouble in H.V circuit (No Raster) Is 175V line voltage normal? No Trouble in power supply circuit Yes Trouble in Q601 or FBT Yes Trouble in Q603, Q604 12V Line Yes Is Q601 Gate waveform normal? No Is Q604, Q603 Base waveform normal? No Is IC601 pin 10 normal? No Trouble in IC601 Yes Is the IC601 pin5 H.trigger correct? No Trouble in H.trigger 27 Yes Trouble in IC601 ambient circuit.
11. Side-Pincushion Circuit Side-Pincusion distortion is excessive or barrel Select the side-pincushion icon on OSD menu, and adjust acceptable position. Yes O.
12. Power Supply Unit (P.S.U) Trouble in P.S.U Is power switch on? No Switch on Yes Is fuse F001 O.K? No Check the power cord outlet and diode D001, D002, D003, D004 No Trouble in D001, D002, D003, D004, C004 and TH001. No Trouble in T001, IC001, IC101, IC002 and D007 etc.
A Is voltage of C117 14.3Vdc? No Trouble in D103 or horizontal Part. No Trouble in D643 or vertical Part. Yes Is voltage of C643 -15Vdc? Yes Is voltage of C112 25Vdc? No Trouble in D105 Yes P.S.U O.
31 H GND L SDA SCL V H B G R FILTER KS88C6224 MICOM 2SK2101 KA3842 SMPS TRANS SMPS 110V,175V,24V, 13V, +/-12V,HT H,V SYNC. SDA,SCL TILT CIRCUIT EEPROM 24C08 KA2500 SDA,SCL H,V SYNC. SCL, SDA KS2508 OSD IC VIDEO PREAMP B+ CONTROL H. DRV. uPC1888CT H. OSC & V. DRV. TDA9302H V. DRV. AMP H. DY V. DY TDA9532 VIDEO OUTPUT AMP & BIAS KA7500B B+ CONTROL H. VTG FBT H.
SCHEMATIC DIAGRAM 35
EXPLODED VIEW & MECHANICAL PARTS LIST 36
INFORMATION OF PART DESCRIPTION Important Safety Notice Components identified with the International Symbol have special characteristics important for safety. When replacing any components, use only manufacturer’s specified parts. Abbreviation of Description RESISTOR Description Allowance F ± 1% J ± 5% K ± 10% M ± 20% G ± 2% Example: Fig & Index Part No Description Resistors RD-4Z820J Carbon: 82J RD-4Z201J Carbon1/4W-200J R101 R102 CAPACITOR Description C D F J K P Z Allowance ± 0.25pF ± 0.
ELECTRICAL PARTS LIST The components identified by mark ! have special characteristics important for safety and x-ray radiation. These should be replaced only with the types specified in the parts list. LOC PART-CODE PART-NAME LOC PART-DESC PART-CODE PART-NAME PART-DESC B001 5PB13890-- COIL BEAD BI3890 C204 CXCH1H330J C CERA 50V CH 33PF J (TAPPING) B002 5PB13857-- COIL BEAD BI3857(AXIAL) C205 CCXF1H103Z C CERA 50V F 0.
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC C540 CMXF2D364J C MYLAR 200V MPP 0.36MF J (TP) C811 CCZF1H104Z C CERA 50V HIKF 0.1MF Z C541 CMXF2G154J C MYLAR MPP 400V 0.15MF J C812 CEXF1H100V C ELECTRO 50V RSS 10MF (5X11) TP C542 CMXF2G104J C MYLAR MPP 400V 0.1MF J C813 CCZF1H104Z C CERA 50V HIKF 0.1MF Z C551 CEXF1H101V C ELECTRO 50V RSS 100MF (8X11.5) TP C814 CEXF1H100V C ELECTRO 50V RSS 10MF (5X11) TP C552 CMXM2A104J C MYLAR 100V 0.
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC D603 DZN4148--- DIODE 1N4148 AUTO 52MM L531 5MH0000075 COIL H-LINEARITY TRL-715B D605 DER206---- DIODE ER206 L801 5CPZ101K02 COIL PEAKING 100UH K (AXIAL 3.5MM) D607 DZN4148--- DIODE 1N4148 AUTO 52MM L802 5CPZ101K02 COIL PEAKING 100UH K (AXIAL 3.5MM) D608 DRU3C----- DIODE RU 3C L803 5CPZ338K02 COIL PEAKING 0.33UH K (AXIAL 3.5MM) D641 D1A5G----- DIODE 1A5G L804 5CPZ100K02 COIL PEAKING 10UH K (AXIAL 3.
LOC PART-CODE Q704 TKSC5042F- PART-NAME LOC PART-NAME PART-DESC R235 RD-AZ103J- R CARBON FILM 1/6 10K OHM J R237 RD-AZ124J- R CARBON FILM 1/6 120K OHM J R002 RS01Z333J- R M-OXIDE FILM 1W 33K OHM J (TAPPING) R238 RD-AZ623J- R CARBON FILM 1/6 62K OHM J R003 RS01Z333J- R M-OXIDE FILM 1W 33K OHM J (TAPPING) R239 RD-AZ203J- R CARBON FILM 1/6 20K OHM J R004 RS01Z333J- R M-OXIDE FILM 1W 33K OHM J (TAPPING) R240 RD-AZ561J- R CARBON FILM 1/6 560 OHM J R005 RS01Z104J- R M-OXIDE FILM 1W 100K OH
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC R542 RD-AZ103J- R CARBON FILM 1/6 10K OHM J R632 RD-4Z563J- R CARBON FILM 1/4 56K OHM J R543 RD-AZ104J- R CARBON FILM 1/6 100K OHM J R633 RD-AZ391J- R CARBON FILM 1/6 390 OHM J R544 RD-AZ183J- R CARBON FILM 1/6 18K OHM J R641 RD-AZ103J- R CARBON FILM 1/6 10K OHM J R545 RD-AZ122J- R CARBON FILM 1/6 1.
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE R843 RD-AZ330J- PART-NAME PART-DESC R816 RD-AZ391J- R CARBON FILM 1/6 390 OHM J R817 RD-AZ100J- R CARBON FILM 1/6 10 OHM J R818 RD-AZ472J- R CARBON FILM 1/6 4.7K OHM J SC R819 RD-AZ472J- R CARBON FILM 1/6 4.7K OHM J SC001 9970710201 R820 RD-AZ472J- R CARBON FILM 1/6 4.7K OHM J SG301 4SG0D00104 SPARK GAP S-23 1.5KV R821 RD-AZ101J- R CARBON FILM 1/6 100 OHM J SG302 4SG0D00104 SPARK GAP S-23 1.
DAEWOO ELECTRONICS CO., LTD 686, AHYEON-DONG MAPO-GU SEOUL, KOREA C.P.O. BOX 8003 SEOUL, KOREA TELEX : DWELEC K28177-8 CABLE : "DAEWOOELEC" E-mail : djkoo@web.dwe.co.
