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COLOR MONITOR
SERVICE MANUAL
CHASSIS NO. : CA-119
FACTORY MODEL: CB773H
MODEL: StudioWorks 773N (CB773H-ML),
StudioWorks 773E (CB773H-EL),
(CB773H-NJ), (CB773H-EJ), TINY773N (773N Rev B)
*( ) ID LABEL Model No.
CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
MENU SELECT
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CONTENTS SPECIFICATIONS ................................................... 2 DESCRIPTION OF BLOCK DIAGRAM................... ..9 ADJUSTMENT ...................................................... 10 SAFETY PRECAUTIONS ........................................ 3 TROUBLESHOOTING GUIDE .............................. 12 TIMING CHART ....................................................... 4 EXPLODED VIEW................................................... 22 OPERATING INSTRUCTIONS .....................
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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. parts list. It is essential that these critical parts should be The basic precaution which must be exer
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TIMING CHART VIDEO C B SYNC E F D A << Dot Clock (MHz), Horizontal Frequency (kHz), Vertical Frequency (Hz), Horizontal etc... (µs), Vertical etc... (ms) >> Sync H/V Total Period Video Active Blanking Time Sync Duration Back Porch Front Porch Mode Frequency Resolution (F) Polarity (A) Time (B) (C) (E) (D) Sort H – 37.50 26.67 20.32 6.35 2.03 3.81 0.51 640x480 1 75Hz V – 74.99 13.335 12.802 0.533 0.080 0.427 0.026 H + 46.88 21.33 16.16 5.17 1.62 3.23 0.32 800x600 2 75Hz V + 75.01 13.331 12.798 0
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OPERATING INSTRUCTIONS FRONT VIEW REAR VIEW ID Label MENU SELECT Power ON/OFF Button AC Power Socket See Front Control Panel Signal Connector Front Control Panel MENU SELECT 5 4 3 2 1 4. SET 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. screen display. 2. Power Indicator 5. MENU Button This indicator lights up green when the monitor operates normally; in DPMS (Energy Saving) mode, -stand-by, Use this button to
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WIRING DIAGRAM P402 P501 P701 + S S P702 T1 AC Socket P902 Signal Cable P302 P301 G2 - 6 - FBT
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BLOCK DIAGRAM Dynamic Focus Static Focus G1 Screen(G2) - 7 - < OSD Control > H.V 105V SELECT Heater ( 6.3V ) Signal H-Sync Sig R Cable OSD VIDEO POWER V-Sync Sig VIDEO ON/OFF G PRE-AMP DY CDT MAIN AMP 2 B I C DATA(SDA) (IC302) (IC303) 2 H / V POSITION STV9211 I C CLOCK(SCL) STV9556 H / V SIZE SPCC TRAPIZODE OSD IC 5V MICOM 13V 5V 2 PIN BALANCE (IC301) I C SCL / SDA (IC401) PARALLELOGRAM WT6805 5V H/V Sync, ROTATION R/G/B PWM Control RECALL Drive/Contrast 2 I C DEGAUSS Cut-Off COLOR CURVE MOIRE
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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. this monitor flowing out through the power input line. This circuit consists of the STV9302(IC601) and the That is to say, this circuit prevents interference between associated circ
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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. CRT cathode. 16. Video Pre-Amp Circuit. This circuit amplifies the analog video signal from 0-0.7V to 0-4V. It is operated by taking the clamp, R, G, B drive and co
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ADJUSTMENT GENERAL INFORMATION 7) Adjust tilt as arrow keys to be the best condition. All adjustment are thoroughly checked and corrected 8) DIST. ADJ. → BALANCE command. when the monitor leaves the factory, but sometimes several adjustments may be required. 9) Adjust parallelogram as arrow keys to be the best Adjustment should be following procedure and after condition. warming up for a minimum of 30 minutes. 10) Adjust balance of pin-balance as arrow keys to be the best condition. • Align
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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 4. 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!!” message of monitor. program. 3) Exit from the alignment program. 17-1) Adjust R-DRIVE and G-DRIVE command to white 4) Power switch OFF/ON for EDID data save. balance x=0.283±0.003 and y=0.298±0.003 on the White Ba
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TROUBLESHOOTING GUIDE 1. NO POWER NO POWER (POWER INDICATOR OFF) NO CHECK TROUBLE IN FUSE FUSE OK? (F901) YES CHECK C908 VOLTAGE? NO TROUBLE IN (AC120V: 160VDC, D900 AC220V: 304VDC) YES CHECK NO TROUBLE IN Q901 PIN 6 Q901 WAVEFORM ? YES CHECK TROUBLE IN NO D941, D942, D941, D942, D951, D951, D961, D971 D961, D971 VOLTAGE? YES TROUBLE IN Q903, Q952, Q951, Q942, Q941 - 12 -
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2. NO CHARACTER NO CHARACTER CHECK TROUBLE IN NO IC302 P302 5V LINE PIN 7(5V) ? YES TROUBLE IN CHECK NO PC SIGNAL, IC302 PIN 1, 3, 5? P301 SIGNAL CABLE YES CHECK NO TROUBLE IN IC302 PIN 14, 16, 18 ? IC302 YES CHECK TROUBLE IN NO IC303 PIN 7 (105V) P303 12V LINE/ PIN 3 (13V) ? 80V LINE YES CHECK NO TROUBLE IN IC303 IC303 PIN 1, 2, 4 ? YES TROUBLE IN CHECK NO R331~R333, R, G, B CATHODE L311~L313, VOLTAGE? D307~D312 YES TROUBLE IN CRT SOCKET - 13 -
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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 NO TROUBLE IN D712 ANODE D712 (-160V)? YES CHECK NO TROUBLE IN G1 VOLTAGE? Q799 (-55V~-15V) YES CHECK TROUBLE IN NO CDT HEAT D941, Q942, Q941 VOLTAGE? (6.3V) YES TROUBLE IN CDT - 14 -
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4. NO HORIZONTAL DEFLECTION NO H-DEFLECTION (ONE VERTICAL LINE) NO CHECK TROUBLE IN Q706? Q706 YES CHECK NO TROUBLE IN + B VOLTAGE 50V LINE (50V)? YES CHECK T701(FBT) PIN 2 NO TROUBLE IN (31KHZ 60V, Q719, Q703, Q704, D710 69KHZ 140V) ? YES CHECK TROUBLE IN NO Q705 COLLECTOR Q705 WAVEFORM? YES 0V T TROUBLE IN T701, P701 - 15 -
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5. TROUBLE IN H-LINEARITY UNBALANCED OF H-LIN. CHECK NO TROUBLE IN IC401 IC401 (MICOM) PIN 5, 6, 7 ? YES CHECK NO TROUBLE IN Q711~Q716? Q711 ~ Q716 YES CHECK NO TROUBLE IN L703? L703 YES Cs SIGNAL TABLE HORIZONTAL Cs1 Cs2 Cs3 FREQUENCY(fH) 30K ~ 33.9K L L L TROUBLE IN 34K ~ 38.9K L H L C722, C723, C726, C729 39K ~ 43.9K H L L 44K ~ 48.9K H L H 49K ~ 51.9K H H L 52K ~ 57.9K H H L 58K ~ 61.9K H H L 62K ~ 65.9K H H H 66K ~ 71K H H H - 16 -
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6. NO VERTICAL DEFLECTION NO V-DEFLECTION (ONE HORIZONTAL LINE) CHECK NO TROUBLE IN IC601 PIN 2 D610 13V LINE (13V+)? YES CHECK NO TROUBLE IN IC701 PIN 23? IC701 3V YES TROUBLE IN IC601, V-CIRCUIT - 17 -
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7. TROUBLE IN OSD NO OSD (ENTER BUTTON MUST BE PRESSED.) CHECK NO TROUBLE IN + IC301 B 5V LINE (5V) ? DC 5V YES CHECK TROUBLE IN NO IC301 PIN 5, 10 IC601 PIN1 (V-FBP), WAVEFORM? T701 40V LINE (H-FBP) Pin 10 5V YES Pin 5 CHECK TROUBLE IN NO IC301 PIN 12 IC302, IC301 WAVEFORM ? H+V 5V YES CHECK NO TROUBLE IN IC301 PIN 13, 14, 15 ? IC301, IC302 H+V 5V YES TROUBLE IN OSD PERIPHERAL CIRCUIT - 18 -
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8. TROUBLE IN DPM (NO OFF MODE.) OFF MODE FAILURE CHECK CHECK PC, IC401 (MICOM) NO INPUT H/V SYNC SIGNAL (PC IS NOT GOING INTO PIN 30, 31 (H/V INPUT) DPM OFF MODE) SIGNAL? YES H/V SYNC CHECK NO TROUBLE IN IC401 PIN 13 X401 WAVEFORM? 5V YES 24MHz CHECK NO (DPMF: 0V) TROUBLE IN IC401 (MICOM) IC401 (MICOM) PIN 19, 27 ? SEE DPM TABLE YES CHECK + NO B LINE TROUBLE IN (6.3V,13V+, 105V) ? Q941, Q942, Q951, Q952, DPM TABLE YES Item DPMS LED DPMF Mode TROUBLE IN PC H GREEN H NORMA
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9. NO DEGAUSSING NO DEGAUSSING (DEGAUSS ON THE OSD MENU MUST BE PRESSED.) CHECK NO TROUBLE IN IC401 PIN 1 IC401 (MICOM) (0V)? YES CHECK NO TROUBLE IN Q953 COLLECTOR Q953 VOLTAGE? DC 15V YES CHECK NO TROUBLE IN P902 ? P902 YES NO CHECK TROUBLE IN RL901? RL901 YES TROUBLE IN TH901, DEGAUSSING COIL - 20 -
