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pg.32

1428-30k series

Summary of Contents for 1428-30k series

Page 1: ...S E R V I C E M A N U A L 1428 30K Series Color Monitors Copyright 1997 Produced by M M ...

Page 2: ...GNALS Video Red Green Blue separate input Impedance 75 ohm amplitude 0 7Vp p Horizontal scan 31 5 KHz 35 5 KHz TTL positive or negative Vertical signal 50 70Hz VIDEO CHARACTERISTICS Video bandwidth 45MHz Power supply universal 90 250vAC Resolution VGA sVGA Linear distortion 10 max Geometric distortion 3 0mm max top bottom 4 0mm max left right ENVIRONMENTAL CONDITIONS Operating temp 0 55 degree C C...

Page 3: ...RIZONTAL size VERTICAL size CONTRAST BRIGHTNESS VERTICAL center HORIZONTAL phase SUB BRIGHTNESS RASTER center SUB SIZE VERTICAL lin SUB HORIZ size X RAY prot HORIZONTAL hold B adj PINCUSHION GAIN R G B bias R B Gain WARNING FOR CONTINUED SAFETY REPLACE SAFETY CRITICAL COMPO NENTS ONLY WITH MANUFACTURER RECOMMENDED PARTS AVERTISSEMENT POUR MAINTENIR LE DEGRE DE SECURITE DE L APPAREIL NE REMPLACER L...

Page 4: ... and mechanical parts in display sets have special safety related characteristics These characteristics are often not evident from visual inspection nor can the protection afforded by them necessarily be obtained by using replacement compo nents rated for higher voltage wattage current etc 5 If severe arcing occurs remove AC power immediately and determine the cause by visual inspection incorect i...

Page 5: ...and other tube voltages are adjusted to the recommended values SHOCK HAZARD To remove any residual charge short the anode contact button located in the funnel of the tube to the external conductive coating before handling the tube TUBE HANDLING Tube assembly should never be handled by the tube neck deflection yoke or other neck components If suspending the tube assembly from the mounting lugs en s...

Page 6: ...il con T602 FBT Tunning cap C611 Damping diode D602 Horiz drive trafo T601 Horiz Output Q602 Driver Resistor R615 VR602 X Ray VR308 sub H size VR604 Raster cent VR601 H Hold VR310 V Lin LED power indic POWER SUPPLY Bridge Rectifier Q501 MOSFET L501 FCC choke SYNC SECTION VERT SEC L603 Linearity coil VR CONTROL INFORMATION CONNECTORS INFORMATION PRINCIPAL SECTIONS AREA KRISTEL 100 100 1428 30K PCB ...

Page 7: ...602 Horiz drive trafo T601 Horiz Output Q602 Driver Resistor R615 VR602 X Ray VR308 sub H size VR604 Raster cent VR601 H Hold VR310 V Lin LED power indic POWER SUPPLY Bridge Rectifier Q501 MOSFET L501 FCC choke SYNC SECTION VERT SEC L603 Linearity coil KRISTEL 100 100 1428 30K PCB rev A FIG 1A FIG 2A NOTE for AutoBias optional configuration B902 is NOT used and B901 is like in fig 2A B902 AUTOBIAS...

Page 8: ...e Gain adj video conn LM1203 PREAMPLIFIER CIRCUIT R208 contrast conn DAG spring conn R236 R233 R286 Load Resistors G2 connector GND clamp GND V H sync conn to B901 main PCB G1 ABL and GND connect to B901 main PCB GND2 to B503 main PCB 12vDC from B503 main PCB B from B503 main PCB 7vDC heater from B503 main PCB BLK Blanking from B902 main PCB CRT socket ...

Page 9: ...IER 3 channel IC201 blue wire HR red wire ABL CONTRAST CONNECTOR GND5 ground yellow wire Vsync blue wire Hsync P201 LOGIC CONNECTOR CRT socket large or small neck NOTE small neck ABN02CX large neck ABN02C red wire HTR1 blue wire 88vDC black wire GND2 gray wire GND3 GND1 dag spring connect G2 pin connector white wire 12vDC CRT BOARD ver ABN02CX green wire GP white wire VR yellow wire G1DRV ...

Page 10: ...e video output stages Q205 Q202 Q206 and Q207 comprise the Red Video Output stage The Auto matic Biasing System adds a Bias Control Processor IC202 plus Beam Current Buffers IC203B D a G1 control circuit IC203A and clamping circuits IC201 contains three video preamplifiers with DC controlled gain and DC clamping IC202 contains timing circuits sample and hold circuits and buffers The three video ch...

Page 11: ...1428 30k series AUTO BIAS ...

Page 12: ...0k series TOP OVERLAY KRISTEL 100 100 1428 30K PCB PURPLE Power Supply Section RED Sync Processing Section BLUE Vertical Section GREEN Horizontal Output Section YELLOW HV Section FBT CORAL Electronic Width Control ...

Page 13: ...ked area with red square is subject to be changed accordingly with the model of the CRT and the characteristics of the deflection yoke existing on the CRT Actual schematics is not refered as autobias video board pg 8 1428 30k series TO B503 main PCB B211 to B901 main PCB To B801 main PCB G1 ABL GND ...

Page 14: ...s BLOCK DIAGRAM 100 100 1428 30K OPTIONAL for AUTOBIAS VERTICAL YOKE HORIZONTAL YOKE 110 240 vAC CHARACTERISTICS of potentiometers NOT USED in AB configuration Hsize VR307 5Kohm Vsize VR309 10Kohm Contrast VR201 10Kohm Vcent VR302 5Kohm Hphase VR604 Brightness VR901 100kohm ...

Page 15: ... CIRCUIT pg 10 1428 30k series FUNCTIONAL BLOCK DIAGRAM Switching Power Supply The power circuit includes the lines filter input rectifier circuit start up current mode control and OVP Please refer to the circuit diagram to Q803 coll to R815 R604 L601 to R615 IC301 to pin2 FBT to R339 R331 ...

Page 16: ...for driving the gate of Q501 The current mode sensing resistor R513 senses the primary current wave in order to control the current mode PWM and limit the total output power Pin 2 and pin 1 is an error AMP section IC501 detects the output voltage while the line voltage and load current change 1 5 OVP CIRCUIT ZD502 is the OVP circuit over voltage protection If an over voltage condition exists the Z...

Page 17: ...l horizontal and vertical sync signal Pin 7 works as a frequency discrimination which is active low Pin 9 and 14 work as mode selector which controls output These output pins are to control Vsize Hphase and Hosc of every display mode 3 HORIZONTAL VERTICAL PROCESSOR The IC 601 is a combination horizontal and vertical processor The vertical SYNC is applied to pin 14 of IC601 Oscillation is determine...

Page 18: ... C611 D602 D610 and H DY The parabolic wave is fed to the base of Q303 via double integrated circuit wich can generate a side pincush ion compensation wave The H width control voltage and parabolic wave are amplified by Q304 and Q306 then they are fed to the diode modulator for controlling the source voltage of the horizontal deflection circuit pg 14 1428 30k series ELECTRONIC WIDTH CONTROL schema...

Page 19: ...o amplify each R G B channel The value for channel gain is calculated by collector and emitter resistances The L205 L204 and L205 are series peaking inductors The output amplifier circuit stage consisting of Q202 Q205 Q206 and Q205 is used to amplify video signal to 40Vp p and is represent one of the R G B channels SG202 SG201 and SG203 respectively R252 and R253 are arc protection components whic...

Page 20: ...pg 16 1428 30k series ELECTRICAL DATA AND RATINGS CHUNGHWA 14 ...

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Page 22: ... for standard VGA mode of 480 lines WARM UP TIME Minimum 15 minutes is required for warming up the monitor Direction CRT faces East Ambient lighting environment 400 to 600 lux AMBIENT TEMPERATURE 25 C 77 F TESTING MODE 640x480 800x600 upon request TOOLS and TEST EQUIPMENT Required miniature flat screw driver plastic Hex wrench ass t clips and 1μF 50v capacitor external degaussing coil color analyz...

Page 23: ...arity adjustment adjust VR310 to allow no more than 3 0mm max misadjustment Vertical size is performed from VR309 remote control potentiometer Width size adj is performed from VR307 and VR501 maximum attention for heater voltage maximum permissible value must be between 5 9 6 5vDC Horizontal raster centering is performed from VR604 Horizontal Phase adjustment input 31 5kHz timing with crosshatch p...

Page 24: ...ired previous experience display magenta color pattern adjust the purity magnet so that the picture is in magenta color By turning two overlap ping pawls in opposite directions move them until they are at the same angle 9 o clock and 3 o clock respectively as shown in fig 1 for static convergence adj as shown in fig 2 and fig 3 follow the next steps a display magenta crosshatch pattern b open the ...

Page 25: ... pg 21 1428 30k series CONVERGENCE and PURITY ...

Page 26: ... pg 22 1428 30k series MORE INFORMATION regarding convergence and purity R G B bias R B gain P 201 ...

Page 27: ...pg 23 1428 30k series TROUBLE SHOOTING GUIDE ...

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Page 41: ... R360 2 2 2W R923 6 8K R921 2 2K C313 100U 25V R361 470 R804 1M R910 2 2K Q906 C945 C540 100U 25V L603 H LIN R634 1K C615 4 7uF 50V L501 25MH BD501 KBL06G 4A600V L503 18uH F501 T3A 220V T3 15 110V Q501 FS7KM 16 AC SW AC100V 240V ZD502 18V C508 0 22U MEF DEGAUSSING COIL R521 4 7K C517 472 AC400V R501 5R NTCR L604 18UH R522 10K 2W R633 1 3W PT501 14 PTCR D506 MR856 C814 100U 25V R524 180 C511 0 1U R...

Page 42: ...1428 30k series AUTO BIAS SCHEMATIC DIAGRAM 1428 30K AUTO BIAS ...

Page 43: ...1428 30k series 555 South KIRK Road ST CHARLES IL 60174 phone 630 443 1290 fax 630 443 1390 CREATION PERFECTION TEAMWORK ...

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