MODEL: E74 COLOR MONITOR SERVICE MANUAL CHASSIS NO. : CA-119 CAUTION BEFORE SERVICING THE UNIT, MENU SELECT READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
SAFETY PRECAUTIONS SAFETY-RELATED COMPONENT WARNING! X-RADIATION There are special components used in this color monitor The only potential source of X-radiation is the picture tube. which are important for safety. These parts are marked However, when the high voltage circuitry is operating on the schematic diagram and the replacement properly there is no possibility of an X-radiation problem.
TIMING CHART VIDEO SYNC << Dot Clock (MHz), Horizontal Frequency (kHz), Vertical Frequency (Hz), Horizontal etc... (µs), Vertical etc... (ms) >> Sync Total Period Video Active Sync Duration Blanking Time Back Porch Front Porch Mode Resolution Frequency Time (A) Polarity Sort –...
OPERATING INSTRUCTIONS FRONT VIEW REAR VIEW ID Label MENU SELECT Power ON/OFF Button See Front Control Panel AC Power Socket Signal Connector Front Control Panel MENU SELECT Button 1. Power ON/OFF Button Use these buttons to choose or adjust items in the on Use this button to turn the monitor ON or OFF.
DISASSEMBLY 1. TILT/SWIVEL & BACK COVER REMOVAL 1) Set the monitor face downward. 2) Pull the latch (a), carefully remove the Tilt/Swivel by pulling it upward. 3) Pressing the latch (b), Back cover by pushing it upward. 4) Release the latch (c). 5) Slide the Back Cover away from the Front Cabinet of the monitor.
DESCRIPTION OF BLOCK DIAGRAM 1. Line Filter & Associated Circuit. 6. Horizontal and Vertical Oscillation. This is used for suppressing noise of power input line This circuit generates the horizontal pulse and the vertical flowing into the monitor and/or some noise generated in pulse by taking the H and V sync signal.
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15. Image Rotation (Tilt) Circuit. 17. Video Output Amp Circuit. This circuit corrects the tilt of the screen by supplying the This circuit amplifies the video signal which comes from image rotation signal to the tilt coil which is attached near the video pre-amp circuit and amplified it to applied the the deflection yoke of the CRT.
- Install the cable for adjustment such as Figure 1and run 2) Press the DEGAUSS on the OSD menu for the alignment program on the DOS for IBM compatible PC. demagnetization of the CDT. - Set external Brightness and Contrast volume to max position.
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14) Set Brightness and Contrast to Max position. 5. Input EDID Data. 1) Display color 15,0 cross hatch pattern at Mode 10. 15) Set SUB-CONTRAST 200(C8) (decimal) position. 2) EEPROM → Write EDID command and confirm 16) Set B-DRIVE to 150(96) at DRIVE of the alignment “EDID Write OK!!”...
TROUBLESHOOTING GUIDE 1. NO POWER NO POWER (POWER INDICATOR OFF) CHECK TROUBLE IN FUSE FUSE OK? (F901) CHECK C908 VOLTAGE? TROUBLE IN (AC120V: 160VDC, D900 AC220V: 304VDC) CHECK TROUBLE IN Q901 PIN 6 Q901 WAVEFORM CHECK TROUBLE IN D941, D942, D941, D942, D951, D951, D961, D971 D961, D971...
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2. NO CHARACTER NO CHARACTER CHECK TROUBLE IN IC302 P302 5V LINE PIN 7(5V) ? TROUBLE IN CHECK PC SIGNAL, IC302 PIN 1, 3, 5? P301 SIGNAL CABLE CHECK TROUBLE IN IC302 PIN 14, 16, 18 ? IC302 CHECK TROUBLE IN IC303 PIN 7 (105V) P303 12V LINE/ PIN 3 (13V) ?
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3. NO RASTER NO VIDEO (POWER INDICATOR ON) CHECK AMBER DPM MODE POWER INDICATOR (NO H and/or V SYNC) GREEN or AMBER? GREEN CHECK TROUBLE IN D712 ANODE D712 (-160V)? CHECK TROUBLE IN G1 VOLTAGE? Q799 (-55V~-15V) CHECK TROUBLE IN CDT HEAT D941, Q942, Q941 VOLTAGE? (6.3V)
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4. NO HORIZONTAL DEFLECTION NO H-DEFLECTION (ONE VERTICAL LINE) CHECK TROUBLE IN Q706? Q706 CHECK TROUBLE IN B + VOLTAGE 50V LINE (50V)? CHECK T701(FBT) PIN 2 TROUBLE IN (31KHZ 60V, Q719, Q703, Q704, D710 69KHZ 140V) ? CHECK TROUBLE IN Q705 COLLECTOR Q705 WAVEFORM?
5. TROUBLE IN H-LINEARITY UNBALANCED OF H-LIN. CHECK TROUBLE IN IC401 IC401 (MICOM) PIN 5, 6, 7 ? CHECK TROUBLE IN Q711~Q716? Q711 ~ Q716 CHECK TROUBLE IN L703? L703 Cs SIGNAL TABLE HORIZONTAL FREQUENCY(fH) 30K ~ 33.9K TROUBLE IN 34K ~ 38.9K C722, C723, C726, C729 39K ~ 43.9K...
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6. NO VERTICAL DEFLECTION NO V-DEFLECTION (ONE HORIZONTAL LINE) CHECK TROUBLE IN IC601 PIN 2 D610 13V LINE (13V+)? CHECK TROUBLE IN IC701 PIN 23? IC701 TROUBLE IN IC601, V-CIRCUIT - 18 -...
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7. TROUBLE IN OSD (ENTER BUTTON MUST BE PRESSED.) NO OSD CHECK TROUBLE IN IC301 B + 5V LINE (5V) ? DC 5V CHECK TROUBLE IN IC301 PIN 5, 10 IC601 PIN1 (V-FBP), WAVEFORM? T701 40V LINE (H-FBP) Pin 10 Pin 5 CHECK TROUBLE IN...
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8. TROUBLE IN DPM (NO OFF MODE.) OFF MODE FAILURE CHECK CHECK PC, IC401 (MICOM) INPUT H/V SYNC SIGNAL (PC IS NOT GOING INTO PIN 30, 31 (H/V INPUT) DPM OFF MODE) SIGNAL? H/V SYNC CHECK TROUBLE IN IC401 PIN 13 X401 WAVEFORM? 24MHz...
9. NO DEGAUSSING NO DEGAUSSING (DEGAUSS ON THE OSD MENU MUST BE PRESSED.) CHECK TROUBLE IN IC401 PIN 1 IC401 (MICOM) (0V)? CHECK TROUBLE IN Q953 COLLECTOR Q953 VOLTAGE? DC 15V CHECK TROUBLE IN P902 ? P902 CHECK TROUBLE IN RL901? RL901 TROUBLE IN...
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10. NO TILT (NO ROTATION ) NO TILT (NO ROTATION) CHECK TROUBLE IN IC401 PIN21 IC401 ( MI COM) WAVE FORM ? CHECK 13V LINE TROUBLE IN 15V LINE, 6.3V LINE AND 6.3V LINE ? CHECK TROUBLE IN Q503 EMITTER Q501~Q503 VOLTAGE ? TROUBLE IN...
EXPLODED VIEW PARTS LIST Part No. Ref. No. Description 3091TKC061R CABINET ASSEMBLY, CB777G IBM C055 E74 320T 9930 BK SP LOCAL 6318L17006B CDT(CIRC), M41LFQ803X 55QLUD LG-PHILIPS 70KHZ 29.1MM FST GREEN or 6318L17005B CDT(CIRC), M41LFQ803X 55QLAA LG-PHILIPS 70KHZ 29.1MM FST GREEN...
REPLACEMENT PARTS LIST CAUTION: BEFORE REPLACING ANY OF THESE COMPONENTS, READ CAREFULLY THE SAFETY PRECAUTIONS IN THIS MANUAL. * NOTE SAFETY Mark AL ALTERNATIVE PARTS DATE: 2003. 3. 28. DATE: 2003. 3. 28. *S *AL LOC. NO. PART NO. DESCRIPTION / SPECIFICATION *S *AL LOC.
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