Service Manual XGA COLOR MONITOR Model : 719B 719BF 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 15 TROUBLESHOOTING HINTS 17 BLOCK DIAGRAM 33 PCB LAYOUT 34 SCHEMATIC DIAGRAM 38 EXPLODED VIEW & MECHANICAL PARTS LIST 42 INFORMATION OF PART DESCRIPTION 44 ELECTRICAL PARTS LIST 45
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 719B Control Panel • • Move cursor to the right window on the OSD window. Increase the value of any selected function. • • Move cursor to the left window on the OSD window. Decrease the value of any selected function. • Launch OSD(On-Screen Display) MENU window. • • Move cursor to the high window on the OSD window. Increase the value of V.size or V.center. • • Move cursor to the low window on the OSD window. Decrease the value of V.size or V.center.
719BF Control Panel • • Move cursor to the right window on the OSD window. Increase the value of any selected function. • • Move cursor to the left window on the OSD window. Decrease the value of any selected function. • Launch OSD(On-Screen Display) MENU window. • • Move cursor to the high window on the OSD window. Increase the value of V.size or V.center. • • Move cursor to the low window on the OSD window. Decrease the value of V.size or V.center.
719B Key Process MENU MENU MENU MENU OSD OFF • When you choose the icon on the OSD window, you can exit the OSD screen.
719BF Key Process OSD OFF • When you choose the icon on the OSD window, you can exit the OSD screen.
OSD Functions ICON CONTROL FUNCTIONS PINCUSHION Adjust the left and right margins for more convex or more concave margins. TRAPEZOID Adjust the trapezoid of the screen by moving the lines inward or outward. PARALLELOGRAM Adjust the parallelogram when the screen is leaning left or right. PIN BALANCE Adjust the side balance when the sides of the screen are bowed towards left or right. ROTATION Adjust the rotation when the screen is tilted left or right. (719BF only) T.
ICON CONTROL FUNCTIONS STATUS Display horizontal & vertical frequency and polarity. H. MOIRE Adjust the horizontal picture moire cancellation. V. MOIRE Adjust the vertical picture moire cancellation. LANGUAGE Select language for OSD (5 languages). RECALL Reset the screen to the Factory Preset Display Settings.
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.
(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 control to get the screen luminosity to 32Ft/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 0.
4. Abnormal OSD Font Abnormal OSD Font Is menu key selected? Is OSD Font exist? * If menu key selected. Is +5V Voltage about 5V? No Yes Yes One color is missing Troubie in IC803 or its ambient circuit Yes Is the output of IC803 (pin 13, 14, 15) normal? No Trouble in IC803 and its ambient circuit Yes Refer to Missing Color 20 No Trouble in +5V 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 45V? No Trouble in B+ Booster Circuit (Check the B+section of IC501) Yes Is the H-out waveform of IC501 normal? 11V 0V No Trouble in IC501 Yes Is the Collector wave form of Q504 normal? 10V 0V No Trouble in Q504 Yes Is the Collector waveform of Q505 normal? 66V Yes Trouble in Q505 and its ambient circuit. 21 No Trouble in Q505 and its ambient circuit.
6. Unstable Picture 6-1. Horizontal Unstable picture Is H.Sync input pin of IC501 correct? No 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 6) normal? No Is the output pulse of IC501 (pin 23) normal? No Trouble in V.Sync line or IC501 failure.
7.
7-1. Dynamic Focus FVH FVV * Check after adjusting the static focus finely by VR in FBT Focus is poor ORION : 300V 120V SAMSUNG : 300V 120V DF waveform FVH FVV Is the waveform of the DF pin in FBT correct? Yes 1. Check the CRT socket or connector wire 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 When the H.Size on the OSD is changed, is the H.size changed? No Yes It isn’t out of order.
9-2. Vertical Size Abnormal V.Size Is changeable the DC voltage of IC401 pin 6? No Is the 3.5Vdc of pin 23 of the IC501? No Yes Trouble V.OSC/ Deflection Circuit Check the pin 23 of IC501 and its ambient circuit Refer to V.
10. High Voltage Output Circuit Trouble in H.V circuit (No Raster) Is B+(45V) line voltage normal? No Trouble in power supply circuit Yes Trouble in FBT Yes Trouble in IC501 ambient circuit Yes Trouble in IC501 ambient circuit Yes Is Q505 collector waveform normal? No Is IC501 pin 8 normal? No Is the IC501 pin15 H.trigger correct? No Trouble in H.
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.K No Is the pin 5,10 waveform of IC803 correct? Yes Check IC803 or their ambient circuit Yes Check IC803or it’s ambient circuit. No Is the waveform of IC803 pin 7,8? No Trouble in H.
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, Q001 No Trouble in D001, D002, D003, D004, C004 and TH001. Yes Is voltage of T001 pin 7 130V (370V)? Yes Is the waveform of Q001 Drain pin correct? 400Vpp (620Vpp) No Trouble in T001, IC001, Q001 and D009 etc.
A Is voltage of C109 13Vdc? No Trouble in D106 or horizontal part No Trouble in D104 or vertical part Yes Is voltage of C108 -13Vdc? Yes Is voltage of C106 27Vdc? No Trouble in D108 Yes P.S.U O.
33 SMPS Transformer AC INPUT D -SUB RGB H/V IIC Control CRT Driver TDA9536 (SGS Thompson) H/V Moire Cancellation H/V OSC Processor TDA4856 (Philips) MCU NT68P62 (Novatek) Geometrical Compensation IIC Control PWM D/A OSD NT6828 (Novatek) TDA9210 (SGS Thompson) Video Pre- amp (65M Hz) (85MHz) Dynamic Focus H/V B+ PWM EUT V - Driver KA2142B (Samsung) H/Linearity Coil TRL-531 X TRL-719B B+ Booster H-Driver Drive Transformer FBT H/V Converter (Lienchang) H- Size D1273TR : BD677A (Fairchild)
PCB LAYOUT 719B/719BF Main PCB Component Side 34
719B/719BF Main PCB Solder Side 35
719B/719BF CRT PCB Component Side 719B/719BF CRT PCB Solder Side 36
719BF Control PCB Component Side 719BF Control PCB Solder Side 37
SCHEMATIC DIAGRAM Power & Connection Section 38
Control & Vert.
Horizontal Section 40
Video Section 41
EXPLODED VIEW & MECHANICAL PARTS LIST 719B 42
719BF 719B 43
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. ◆ Parts List for 719B & 719BF LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC 00020 W3475N731- CORD POWER 3 H05VV-F 3X0.75 1.
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC C546 CMXM2A682J C MYLAR 100V 6800PF J (TP) C891 CCZB1H221K C CERA 50V B 220PF K C548 CCXF1H104Z C CERA 50V F 0.1MF Z C892 CCZB1H221K C CERA 50V B 220PF K C549 CMXM2A152J C MYLAR 100V 1500PF J (TP) C550 CCXF1H104Z C CERA 50V F 0.1MF Z ! C932 CMXL2E104J C MYLAR CA202 9970770028 CONN AS SMH200-07+YBNH200-07=270 MEU 250V 0.1MF J C551 CCXF1H104Z C CERA 50V F 0.
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC D514 DRGP10D--- DIODE RGP 10-D (TAPPING) IC401 1KA2142--- IC V-OUT KA2142 D515 DZN4148--- DIODE 1N4148 AUTO 52MM IC501 1TDA4856-- IC H.
LOC PART-CODE R001 RC-2Z684J- PART-NAME PART-DESC LOC R CARBON COMP 1/2 680K OHM J PART-CODE PART-NAME PART-DESC R223 RD-AZ101J- R CARBON FILM 1/6 100 OHM J R003 RS01Z513JS R M-OXIDE FILM 1W 51K OHM J SMALL R224 RD-AZ202J- R CARBON FILM 1/6 2K OHM J R004 RS01Z513JS R M-OXIDE FILM 1W 51K OHM J SMALL R225 RD-AZ101J- R CARBON FILM 1/6 100 OHM J R005 RD-AZ102J- R CARBON FILM 1/6 1K OHM J R226 RD-AZ202J- R CARBON FILM 1/6 2K OHM J R007 RD-AZ333J- R CARBON FILM 1/6 33K OHM J R227 R
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC R521 RD-AZ471J- R CARBON FILM 1/6 470 OHM J R576 RD-AZ223J- R CARBON FILM 1/6 22K OHM J R522 RD-AZ122J- R CARBON FILM 1/6 1.
LOC PART-CODE PART-NAME PART-DESC LOC PART-CODE PART-NAME PART-DESC R862 RD-AZ330J- R CARBON FILM 1/6 33 OHM J R972 RD-AZ433J- R CARBON FILM 1/6 43K OHM J R863 RD-AZ360J- R CARBON FILM 1/6 36 OHM J R973 RD-AZ752J- R CARBON FILM R864 RD-4Z201J- R CARBON FILM 1/4 200 OHM J RL001 5SC0101325 SW RELAY R865 RD-4Z121J- R CARBON FILM 1/4 120 OHM J SC001 9970800045 R866 RS01Z519JS R M-OXIDE FILM 1W 5.
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.
