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Daewoo 531B Service Manual - Operation and Adjustment

Manual is about: XGA COLOR MONITOR

Summary of 531B

  • Page 1

    Daewoo electronics co., ltd. Http : //svc.Dwe.Co.Kr service manual xga color monitor model : 531b 532b.

  • Page 2: Servicing Precautions

    3 servicing precautions ◆ general servicing precautions 1. Always unplug the ac power cord from the ac power source before: a. Removing or reinstalling any component, circuit board, module, or any other instrument assembly. B. Disconnecting or reconnecting any electrical plug or other electrical con...

  • Page 3

    4 ◆ 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, ...

  • Page 4

    5 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 repl...

  • Page 5: Technical Information

    6 ◆ 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 ...

  • Page 6: 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 u...

  • Page 7: Pin Connector

    8 pin signal 1 red 2 green 3 blue 4 gnd 5 gnd 6 gnd - red 7 gnd - green 8 gnd - blue 9 +5vdc (option) 10 gnd - h.Sync 11 gnd - v.Sync 12 bi-directional data (sda) 13 horizontal sync 14 vertical sync (vclk) 15 data clock (scl) • degaussing is always required when adjusting purity or convergence. • th...

  • Page 8: Operation and Adjustment

    9 operation and adjustment 531b 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 cur...

  • Page 9: •

    10 • when you choose the icon on the osd window, you can exit the osd screen. Osd off menu menu menu menu d e g a u s s u t l t y e x t u t l t y m e n u m e n u 531b key process.

  • Page 10

    532b 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 t...

  • Page 11: •

    • when you choose the icon on the osd window, you can exit the osd screen. 532b key process osd off menu menu menu menu m e n u m e n u u t l t y e x t u t l t y d e g a u s s.

  • Page 12

    11 osd functions icon control functions adjust the pin corner bottom when the bottom sides of the screen are bowed. B. Pin corner adjust the parallelogram when the screen is leaning left or right. Adjust the pin corner top when the top sides of the screen are bowed. T. Pin corner parallelogram adjus...

  • Page 13

    12 reset the screen to the factory preset display settings. Recall icon control functions adjust the vertical picture moire cancellation. V. Moire adjust the horizontal picture moire cancellation. H. Moire select language for osd (5 languages). Language display horizontal & vertical frequency and po...

  • Page 14: Alignment Procedure

    Alignment procedure ◆ standard adjustment conditions 1. Power source voltage : 100-240vac 50/60hz 2. Aging : take at least 20 minutes warm-up time. 3. Signals video : analog 0.7vpp 75 Ω terminal positive polarity synchronizing : ttl level negative/positive separate deflection frequency horizontal fr...

  • Page 15

    14 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. (c) vertical red and blue lines are converged by varying the angle between the two tabs of th...

  • Page 16: Troubleshooting Hints

    15 troubleshooting hints 1. No character change the contrast & brightness control value to maximum no raster refer to no raster check the peripheral circuit of crt check the video output circuit and its ambient circuit trouble in 12v line of the main pwb check the clamping pulse circuit check the si...

  • Page 17

    16 2. No raster trouble in power supply circuit trouble in power supply circuit trouble in g1 line trouble in fbt or its pin4 ambient circuit high voltage trouble in fbt trouble in 100vdc line of power supply unit refer to trouble in p.S.U refer to trouble in power supply unit. Is crt heater red-hot...

  • Page 18

    17 3. A missing color is input signal normal? One color is missing crt cathode (rk, gk, bk) is normal? Is video output ic802 waveform normal? Each grid (g1, g2) voltage normal? Is the output of pre-amp (ic801,tda9210) pin 14, 16,18 all normal? Check video signal cable or video card. Trouble in ic801...

  • Page 19

    18 4. Abnormal osd font is menu key selected? Is osd font exist? * if menu key selected. Is heater voltage about 6v? Abnormal osd font is the output of ic204 (pin 13, 14, 15) normal? Trouble in heater voltage line. Refer to trouble in p.S.U troubie in ic204 or its ambient circuit trouble in ic204 an...

  • Page 20

    Mode b+ voltage vga 60vdc 68k 130vdc 54khz 110vdc 19 5. Horizontal output circuit is the b+line voltage over 50v? Is the h-out waveform of ic501 normal? Trouble in ic501 trouble in horizontal output circuit (no raster yes no is the collector wave form of q504 normal? Yes yes yes trouble in q505 no n...

  • Page 21

    20 6. Unstable picture 6-1. Horizontal unstable picture is the pulse of pin 26 of the ic501 correct? Trouble in ic501 or its ambient circuit is the pulse of pin 28 of the ic201 correct? Check ic501 and its ambient circuit no no no yes yes is the input h.Sync correct? Check ic201 and its ambient circ...

  • Page 22

    21 6-2. Vertical unstable picture is the 12v,-12vdc line voltage is correct? Refer to p. S. U is the pulse of pin 6 of the ic401 correct? Trouble in vertical d. Y no no no yes yes is the output of pin 8 of ic501 all normal? Check ic401 and its ambient circuit yes check the ic501 and its ambient circ...

  • Page 23

    22 7. Focus monitor remains unfocused check focus vr in fbt is focus acceptable? Trouble in focus circuit (fbt) yes ok no.

  • Page 24

    23 8. Convergence is convergence on the center area bad? Is convergence on the fringe area bad? Adjust static convergence refer to adjustment procedure of convergence yes adjust d.Y location yes no poor convergence.

  • Page 25

    Mode b+ voltage vga 60vdc 68k 130vdc 54khz 110vdc 24 9. Abnormal picture 9-1. Horizontal size trouble in l503, c520 or their ambient circuit trouble in horizontal output circuit check the b+ and anode voltage of crt. Trouble in h.Osc/ deflection circuit refer to horizontal output circuit is the dc l...

  • Page 26

    25 9-2. Vertical size is changeable the dc voltage of ic401 pin 1? Check the ic401 and its ambient circuit check the ic501 and its ambient circuit no no trouble v.Osc/ deflection circuit refer to v.Osc/deflection circuit yes is the 3.5vdc of pin 21of the ic501? Yes abnormal v.Size.

  • Page 27

    26 10. Side-pincushion circuit check the base waveform of the q515 yes pincusion distortion is excessive or barrel o.K select the side-pincushion icon in osd menu, and adjust acceptable position. Yes is the pin 11 waveform of ic501 correct? No no trouble in ic501.

  • Page 28

    27 11. Power supply unit (p.S.U) is the ic001 o.K? Replace ic001 no is voltage of c104 50vdc? No is voltage of d002 130v (270v)? Trouble in switching power transformer t001 or ic001 and its ambient circuit trouble in diode d001,d002,d003,d004 or peripheral device no is the waveform of t001 pin5 corr...

  • Page 29

    28 is voltage of c105 8vdc? Trouble in d103 no is voltage of c109 13vdc? No yes yes yes is voltage of c108 -12vdc? Trouble in d104 or vertical part p.S.U o.K trouble in d106 or horizontal part no a.

  • Page 30: Block Diagram

    29 block diagram 5 3 1 b / 5 3 2 b m o n ito r b lo c k d iag r am crt socket crt : orion mini-neck 15" d -sub rgb h/v video pre-amp (65mhz) tda9210 (sgs thompson) osd nt6828 (novatek) crt driver tda9536 (sgs thompson) ac input smps transformer mcu nt68p62 (novatek) h/v osc processor tda4856 (philip...

  • Page 31

    Pcb layout 30 main pcb component side.

  • Page 32

    31 main pcb solder side.

  • Page 33

    32 crt pcb component side crt pcb solder side.

  • Page 34

    33 schematic diagram - - power & connection section.

  • Page 35

    34 control & vert. Out section.

  • Page 36

    35 horizontal section.

  • Page 37

    36 video section.

  • Page 38

    Exploded view diagram 37.

  • Page 39

    Resistor description example: capacitor description example: fig & part no description index capacitors c110 ccxf1h104z ceramic 50v 0.1µf z c522 ccxb2h331k ceramic 500v 330pf k c402 cmxm 2a154j mylar 100v 0.15µf j 38 tolerance c ± 0.25pf d ± 0.5% f ± 1pf j ± 5% k ± 10% p ± 100% ~ 0% z ± 80% ~ – fig ...

  • Page 40: Electrical Parts List

    39 00001 9979800540 pcb main t=1.6*246*247 (531x) 00002 9979800548 pcb crt t=1.6*108*82(531x) 00020 w3475n731- cord power 3 h05vv-f 3x0.75 1.8 iv b001 5pb13890-- coil bead bi3890 b002 5mbfd3512r coil bead bfd 3512 r2 b006 5pb13890-- coil bead bi3890 b007 5pb13890-- coil bead bi3890 b101 5pb13857-- c...

  • Page 41

    40 c524 cexf2a331v c electro 100v rss 330mf (16x25) tp c527 ccxb3a102k c cera 1kv b 1000pf k (tapping) c528 cmxf2d124j c mylar mpp 200v 0.12mf j c528a cmxf2d104j c mylar mpp 200v 0.1mf j c530 cmxf2d224j c mylar mpp 200v 0.22mf j c531 cmxf2d334j c mylar 200v mpp 0.33mf j (tp) c532 cmyf2d824j c mylar ...

  • Page 42

    41 d517 d1n4007--- diode in4007 d520 dbav20---- diode bav20 d560 drgp10d--- diode rgp 10-d (tapping) d591 dzn4148--- diode 1n4148 auto 52mm d592 dzn4148--- diode 1n4148 auto 52mm d593 dzn4148--- diode 1n4148 auto 52mm d594 dzn4148--- diode 1n4148 auto 52mm d601 dru1p----- diode ru 1p (tapping) d611 ...

  • Page 43

    42 r016 rd-az103j- r carbon film 1/6 10k ohm j r017 rd-az563j- r carbon film 1/6 56k ohm j r018 rd-az823j- r carbon film 1/6 82k ohm j r026 rd-az103j- r carbon film 1/6 10k ohm j r101 rd-az104j- r carbon film 1/6 100k ohm j r104 rd-az103j- r carbon film 1/6 10k ohm j r105 rd-4z331j- r carbon film 1/...

  • Page 44

    43 r527 rd-az102j- r carbon film 1/6 1k ohm j r528 rd-az223j- r carbon film 1/6 22k ohm j r529 rd-2z229j- r carbon film 1/2 2.2 ohm j r530 rd-2z221j- r carbon film 1/2 220 ohm j r532 rd-az153j- r carbon film 1/6 15k ohm j r533 rd-az513j- r carbon film 1/6 51k ohm j r534 rd-az153j- r carbon film 1/6 ...