background image

Improved focus?

Adjust Pole4,Pole6

to improve the misconvergence

24. Misconvergence

Degauss the CDT

Done.

Change CRT and readjust

convergence.

Yes

Done

No

25. Poor Focus

Adjust focus VR.

Check focus leads from

FBT to CRT Socket.

Check the CRT Socket.

YES

Aging monitor and
check for focus change.

NO

Refer to 18 Dynamic
Focus Failure.

NO

Replace the CRT and verify focus.

YES

- 34 -

Dynamic focus circuit is

right?

Summary of Contents for Flatron T717B

Page 1: ...http biz LGservice com E mail http www LGEservice com techsup html CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL MODEL T717B T717BKM K E CHASSIS NO CA 136 Same model for Service Same looking with new chassis ...

Page 2: ... Area Max Image Size 325 1 x 243 8 mm 12 80 x 9 60 Preset Image Size 310x 230 mm 12 20 x 9 06 4 2 Display Color Full Colors 4 3 Display Resolution 1280 x 1024 60Hz Max Non Interlace 4 4 Video Bandwidth 110 MHz 5 ENVIRONMENT 5 1 Operating Temperature 0 C 40 C Ambient 5 2 Relative Humidity 10 80 Non condensing 5 3 Altitude 5 000 m 6 DIMENSIONS with TILT SWIVEL Width 400 mm 15 75 inch Depth 411 mm 16...

Page 3: ...joints frayed leads damaged insulation solder splashes or the sharp points Be sure to remove all foreign materials IMPLOSION PROTECTION All used display tubes are equipped with an integral implosion protection system but care should be taken to avoid damage and scratching during installation Use only same type display tubes X RADIATION The only potential source of X radiation is the picture tube H...

Page 4: ...st receiver ground lead to the receiver chassis ground before connecting the test receiver positive lead Always remove the test receiver ground lead last 9 Use with this receiver only the test fixtures specified in this service manual CAUTION Do not connect the test fixture ground strap to any heat sink in this receiver Electrostatically Sensitive ES Devices Some semiconductor solid state devices ...

Page 5: ...tip as the solder melts 2 Draw away the melted solder with an anti static suction type solder removal device or with solder braid before removing the IC Replacement 1 Carefully insert the replacement IC in the circuit board 2 Carefully bend each IC lead against the circuit foil pad and solder it 3 Clean the soldered areas with a small wire bristle brush It is not necessary to reapply acrylic coati...

Page 6: ...onnection 4 Route the jumper wire along the path of the out away copper pattern and let it overlap the previously scraped end of the good copper pattern Solder the overlapped area and clip off any excess jumper wire At Other Connections Use the following technique to repair the defective copper pattern at connections other than IC Pins This technique involves the installation of a jumper wire on t...

Page 7: ...31 12 798 0 533 0 064 0 448 0 021 800 X 600 H 53 68 18 63 14 22 4 41 1 14 2 70 0 57 3 V 85 07 11 755 11 178 0 577 0 056 0 503 0 018 800 X 600 H 68 677 14 561 10 836 3 725 1 016 2 201 0 508 4 V 85 00 11 764 11 182 0 582 0 044 0 524 0 014 1024 X 768 H 60 289 16 587 12 518 4 068 1 252 2 034 0 782 5 V 74 893 13 352 12 739 0 641 0 116 0 448 0 050 1280 X 768 B A C F D E VIDEO SYNC Mode H V Sort Sync Pol...

Page 8: ...y remove the Tilt S wivel by pulling it upward 3 Remove the screw b Back cover by pushing it upward 4 R elease the latch c S ee Tip S pec 5 S lide the Back Cover away from the Front Cabinet of the monitor Tip C B A Tip S pec A Width 5 0 15 0mm B Depth 0 6 0 9mm C Height 12 0mm a B ack Cover C abinet c b ...

Page 9: ...WIRING DIAGRAM 9 P501 P201 P405 P301 P302 G2 P702 P701 T1 P402 P902 S S Signal Cable AC Socket FBT P203 P202 P220 P904 ...

Page 10: ...it Dynamic FOCUS Circuit Brightness Control 160V 40V D D Feed Back SCL SDA H Sync V Sync PWM Control Signal 50V DY CDT Heater 6 3V I 2 C Screen H V R G B Bias H Drive B Drive B DPM Control Circuit 5V 6 3V 8V 80V Voltage feedback Degaussing Coil Dynamic Focus Static Focus TILT Coil 50V 80V 5V G2 G1 Auto Beam Limit DC DC Converter FBT T701 Regulation Circuit SMPS T901 5V BRIGHTNESS CONTR AST MOIRE D...

Page 11: ...deo drive output block The video drive IC IC302 receives the video signal from PC The gain of each channel is controlled by MICOM through IIC The cut off circuit compensate different voltage of each channel between the cathode and the G1 of the CDT 1 The AC line voltage is rectified by the bridge diode D900 2 The control IC IC901 starts switching and generates switch pulse in the primary turn of t...

Page 12: ...signal from 0 0 7 V to 0 4 V It is operated by taking the clamp R G B drive and contrast signal from the MICOM IC401 16 Video Output Amp Circuit This circuit amplifies the video signal which comes from the video pre amp circuit and amplified it to applied the CDT cathode ...

Page 13: ...x position 1 Adjustment for B Voltage 1 Display cross hatch pattern at Mode 4 2 Check D961 cathode voltage within 50V 1V 2 Adjustment for High Voltage 1 Display cross hatch pattern at Mode 4 2 Enter the SVC SUB menu as the following instruction 3 Adjust H Voltage to 25 8kV 0 1 kV by adjust 1 P value 2 Adjustment by Service Hot key How to enter SVC HOT KEY 1 Press Menu and OSD window will appear 2 ...

Page 14: ...0 Contrast Maximum Brightness Maximum Color temperature 9300K 11 1 Adjustment of cut off Adjustment of back raster 11 1 a Before adjustment press Menu and Degauss to remove Enter hot key mode Adjust Brightness and Contrast to Max in OSD window 1 Adjust cut off back raster first Enter DEGAUSS in the Menu and modify the following data Modify RCUT to Min Modify GCUT To Min Adjust to BCUT Data 127 7F ...

Page 15: ...5Hz 69kHz 85Hz Display image White flat field Luminance Cut off point at the center of the display area Note Color purity adjustments should only be attempted by qualified personnel PROCEDURE For trained and experienced service technicians only Use the following procedure to correct minor color purity problems 1 Make sure the display is not affected by external magnetic fields 2 Very carefully bre...

Page 16: ...t above from number 6 to 16 20 COMMAND PRESET EXIT Y Yes command 2 Adjustment for White Balance and Luminance 1 Set the White Balance Meter 2 Press the DEGAUSSING on the OSD menu for demagnetization of the CDT 3 Display color 0 0 pattern at Mode 4 4 COMMAND PRESET START Y Yes command 5 Set Bightness and Contrast to max position 6 COLOR ADJ LUMINANCE command of the alignment program 7 COLOR ADJ BIA...

Page 17: ...cross hatch pattern at Mode 4 2 Use EEPROM Write EDID command and confirm EDIDWriteOK message of monitor 3 Exit from the alignment program 4 Power switch OFF ON for EDID data save 1 7 T717BKM 0 1 2 3 4 5 6 7 8 9 A B C D E F 0 00 FF FF FF FF FF FF 00 1E 6D 14 44 01 01 01 01 1 01 0F 01 03 18 21 18 B5 EA F6 29 A2 53 47 99 25 2 10 48 4C FF FE 80 31 59 71 4F 45 59 61 59 81 80 3 81 4A 01 01 01 01 EA 24 ...

Page 18: ...V Control Line N o t u s e d R S 2 3 2 C P A R A L L E L V S Y N C P O W E R S T VGS MONIT OR E V Sync On Off Switch Switch must be ON F A B C E F A B C 15 10 5 5 6 9 1 1 1 14 13 25 6 5V 5V 5V 4 7K 4 7K 4 7K 74LS06 74LS06 OFF ON OFF ON 11 VIDEO SIGNAL GENERATOR Figure 1 Cable Connection Figure 1 Cable Connection ...

Page 19: ...D941 D942 D906 CHECK FUSE OK F901 19 TROUBLESHOOTING GUIDE 1 NO POWER NO POWER POWER INDICATOR OFF NO NO NO NO TROUBLE IN Q951 Q952 Q941 Q942 TROUBLE IN FUSE F901 SMPS Switch ON OFF Waveforms TROUBLE IN BRIDGE DIODE D900 TROUBLE IN IC901 Q901 TROUBLE IN D971 D961 D951 D904 D941 D942 D906 YES YES YES YES Q901 Drain IC901 6 2 1 ...

Page 20: ...LE IN IC302 P301 TROUBLE IN IC303 TROUBLE IN IC304 YES YES YES YES 20 CHECK IC302 PIN 5 6 7 CHECK IC302 PIN 1 24 23 19 20 21 PIN 18 5V CHECK IC303 PIN 1 2 3 PIN8 8V PIN 4 80V CHECK R G B CATHODE VOLTAGE IC302 5 6 7 IC302 23 IC302 19 20 21 IC302 1 IC302 24 CDT RK GK BK Waveforms 28 27 30 31 26 27 28 29 30 31 29 ...

Page 21: ...8 PIN20 PIN21 CHECK POWER INDICATOR GREEN or FLASH 21 3 NO RASTER FLASH NO NO NO TROUBLE IN IC401 MICOM TROUBLE IN P302 SIGNAL CABLE ROTATE SCREEN CONTROL KNOB TO CLOCKWISE or COUNTER CLOCKWIES TROUBLE IN PRIMARY CIRCUIT OF T901 TROUBLE IN CDT SOCKET BOARD GREEN YES YES YES NO VIDEO POWER INDICATOR GREEN or FLASH IC401 18 IC401 20 IC401 21 14 7 5 5 14 7 Waveforms ...

Page 22: ...WTOOTH WAVE CHECK IC601 Pin 3 13V 22 4 NO VERTICAL DEFLECTION NO V DEFLECTION ONE HORIZONTAL LINE NO NO NO TROUBLE IN IC601 V CIRCUIT TROUBLE IN T901 13V Line Waveforms TROUBLE IN T701 40V line TROUBLE IN IC401 YES YES YES IC401 33 IC401 34 9 8 8 9 ...

Page 23: ...ROUBLE IN T901 or PC CHECK PC PC IS NOT GOING INTO DPM MODE TROUBLE IN X401 IC401 TROUBLE IN POWER SUPPLY TROUBLE IN IC401 NO TROUBLE IN Q941 Q951 Q942 Q952 NO H V SYNC SIGNAL YES YES YES YES DPMS TABLE NORMAL ON ON NORMAL GREEN STAND BY OFF ON OFF 0V FLASH SUSPEND ON OFF OFF 0V FLASH OFF OFF OFF OFF 0V FLASH H V SYNC VIDEO LED MODE ITEM C401 45 IC401 46 CHECK IC401 PIN 16 5V HIGH 4 3 Waveforms Q9...

Page 24: ...VOLTAGE 0 5V CHECK P902 CHECK RL901 CHECK IC401 PIN 4 5V 6 NO DEGAUSSING NO DEGAUSSING NO NO NO NO TROUBLE IN TH901 DEGAUSSING COIL TROUBLE IN IC401 MICOM TROUBLE IN D953 TROUBLE IN P902 TROUBLE IN RL901 YES YES YES YES 24 ...

Page 25: ...O NO NO NO 1 Check IC401 Pins 39 40 41 2 Replace IC401 Check Q720 50V LINE D710 Check Q704 Check 13V line Check and replace T703 and Q706 Check DY connector connection YES YES YES IC401 18 Q706 Base Q706 Collector Q719 Drain Q705 Drain 5 18 19 21 20 Waveforms 8 Invariable H_Size NO Check and replace IC401 Check if DC voltage of IC401 PIN 35 wave is Variable 6 IC401 35 6 ...

Page 26: ...ROUBLE IN IC401 MICOM TROUBLE IN Q711 Q716 TROUBLE IN L703 TROUBLE IN C722 C723 C726 C729 NO NO NO YES YES YES Cs SIGNAL TABLE HORIZONTAL FREQUENCY fH 30K 33 9K 34K 38 9K 39K 43 9K 44K 48 9K 49K 51 9K 52K 57 9K 58K 61 9K 62K 65 9K 66K 71K Cs1 L L H H H H H H H Cs3 L L L L L H L L H Cs2 L H L L H L H H H ...

Page 27: ...eform Q706 Collector is right 27 10 Abnormal H_Size NO NO Repeat the troubleshooting Guide of H_deflection failure Check D D converter circuit Check IC401 B control circuit YES 11 Side Pin or Trap Failure NO 12 Para or Pin Balance Failure Replace IC401 Check and replace IC401 Q706 Collector IC401 35 21 6 21 6 Waveforms ...

Page 28: ...401 Pin 26 output duty varies with different DAC values 13 Tilt Failure Check tilt connector connection Check and replace CRT NO NO Check and replace IC401 Check Q503 Q501 Q502 YES YES 14 V Size or Pos Variation Failure Check and replace IC401 and IC601 NO Check some parts around IC401 YES 28 IC401 33 IC401 34 Waveforms ...

Page 29: ...ion failure YES YES 16 ABL Failure YES NO Check and replace CRT Input full white pattern to monitor Check P302 D801 R801 803 R798 Check and replace IC302 Check and replace T701 NO YES 29 Q719 Drain Q706 Collector IC302 Pin22 input exists and varies with different patterns T701 Pin 6 Voltage exists 18 18 Waveforms 21 21 YES waveform is right Q719 drain ...

Page 30: ...Pin 24 output are right Q710 and parts around are right 17 Focus Failure NO NO NO Check the connection between FBT Pin 12 CRT Socket PCB Check and replace IC401 Waveforms Replace failed part Replace failed part YES YES YES 30 IC401 24 FBT 12 22 23 ...

Page 31: ... are right IC401 Pin 45 and 46 inputs are right IC401 Pin 16 input is over 4 2V 18 Micom Failure 19 OSD Failure NO NO NO NO Done Change IC302 Check Q903 D908 ZD902 Check X401 Check and replace R451 C408 Replace IC401 YES YES YES YES 31 IC401 45 IC401 46 Waveforms ...

Page 32: ...d replace IC401 Check and replace function key YES 21 Missing Color NO Change the CRT Check signal generator and signal cable NO Refer to 2 No Charcter NO Check and replace IC303 and IC304 NO Check C341 C346 and G2 wire Check around FBT circuits also YES YES YES YES 32 Proper AC voltage are on all cathodes Proper DC voltage are on all cathodes G2 voltage is right ...

Page 33: ...ible Retrace Check white balance adjustment NO NO NO Done Check G2 control volume and FBT Check IC302 and related components Check Q799 and related components YES YES YES 33 Degaussing circuit is right Purity is right 23 Purity Failure Degaussing YES NO Replace CRT and verify purity Done Refer to 6 NO Degaussing NO YES ...

Page 34: ...Done Change CRT and readjust convergence Yes Done No 25 Poor Focus Adjust focus VR Check focus leads from FBT to CRT Socket Check the CRT Socket YES Aging monitor and check for focus change NO Refer to 18 Dynamic Focus Failure NO Replace the CRT and verify focus YES 34 Dynamic focus circuit is right ...

Page 35: ...EXPLODED VIEW 35 10 12 12 13 11 2 11 1 7 B A 2 6 5 a b b 1 d 15 14 15 3 9 c 8 4 ...

Page 36: ...EW PTP 4 20BP MSWR FZMY BRACKET 700BH HOLDER FBT MAIN TOTAL ASSEMBLY T717BKM BRAND M CHASSIS PWB PCB ASSEMBLY MAIN CA 139 T717BKM KLRUEET SCREW DRAWING D3 5 L10 0 MSWR FZMY SW3 5 RW3 5 SCREW ASSEMBLY TAPTITE P TYPE D3 0 L10 0 MSWR FZMY SW3 RW10 SCREW DRAWING PZP 3 10 MSWR FZMY Part No 6318L17023A 3043TKK108J 339 002K 6174T11004F 6620TKB002D or 6620TKB002B 6850TA9018B 68719ST778A 4950TKS331A 4810TK...

Page 37: ... D 100V 5 PE TP5 C417 0CK1040K945 0 1UF D 50V 80 20 F Y5V TR C419 0CQ2221N409 2200PF 100V J PE TP C420 0CQ6831N509 0 068UF D 100V 10 PE TP5 C421 0CK1020K515 1000PF D 50V 10 B Y5P TR C422 0CK2220K515 2200PF D 50V 10 B Y5P TR C423 0CK2220K515 2200PF D 50V 10 B Y5P TR C424 0CE475CK638 4 7UF SHL SD 50V M FM5 TP 5 C426 0CK4710K515 470PF D 50V 10 B Y5P TR C427 0CK4710K515 470PF D 50V 10 B Y5P TR C430 0C...

Page 38: ...48M PCTRONIX TP DO34 100V 75VA 2000MA 4NSEC 0 025UA D703 0DRGF00120A MUR460 15MM GULF BK DO201AD 600V 4A 150A 45NSSEC 10UA D704 0DRFC00300A FFPF04U150STU LF FAIR CHILD BK TO220F 1500V 4A 40A 150NSSEC 7UA D705 0DRTW00089A SRT14 1021 TIWAN SEMI TP NON 40V 1A 25A SEC 0 5MA D706 0DRFC00300A FFPF04U150STU LF FAIR CHILD BK TO220F 1500V 4A 40A 150NSSEC 7UA D710 0DR400409AC UF4004 GULF TP DO41 400V 1A 30A...

Page 39: ... 0TR534309AA 2SC5343Y TP AUK Q719 0TFFC10012A FQPF10N20C FAIRCHILD ST TO220F 200V 9 5A Q720 0TR390409CA FAIRCHILD 2N3904 TA TP TO 92 60V 0 2A Q799 0TRAU80036A SPS92AT AUK KOREA R TP TO92 300V 500MA Q901 0TF760000AD SSS7N60B FAIRCHILD ST TO220F 650V 7A Q903 0TR100809AA KSC1008C Y TP SAMSUNG TO92 NPN Q941 0TR534309AA 2SC5343Y TP AUK Q942 0TRAU80034A STB1277LAT B1273 AUK KOREA R TP TO 92L 30V 2A Q951...

Page 40: ...5 27 OHM 2 W 5 SF R728 0RD1001Q609 1K OHM 1 4 W 3 4 5 00 TA52 R729 0RD1002Q609 10K OHM 1 4 W 3 4 5 00 TA52 R736 0RX2201J609 2 2KOHM 1 W 5 TA52 R737 0RN0560H609 0 56 OHM 1 2 W 5 00 TA52 R738 0RN0560H609 0 56 OHM 1 2 W 5 00 TA52 R739 0RD2701Q609 2 7K OHM 1 4 W 3 4 5 00 TA52 R740 0RD0271A609 2 7 OHM 1 2 W 7 0 5 00 TA52 R744 0RD1001A609 1K OHM 1 2 W 7 0 5 00 TA52 R745 0RD4702Q609 47K OHM 1 4 W 3 4 5 0...

Page 41: ...1280F6 JEIL 12V DC 1MA VERTICAL 7MM SW202 6600R00001A JTP1280F6 JEIL 12V DC 1MA VERTICAL 7MM SW203 6600R00001A JTP1280F6 JEIL 12V DC 1MA VERTICAL 7MM SW204 6600R00001A JTP1280F6 JEIL 12V DC 1MA VERTICAL 7MM SW205 6600M000051 JPS 2225B NAMAE 30VDC 0 1A COVER GRAY T1 6631T11005D 1 W T 480MM UL 1015 AWG 22 CB775C T701 6174T11004F 1063A F700BK 71K JUNGWOO 17 T702 6170TCZ012B EE1916 1 6MH FOCUS TRANS 7...

Page 42: ... 27 01 28 01 29 30 31 01 01 14 01 15 01 16 01 17 01 18 01 19 01 20 01 21 22 01 02 01 03 01 04 01 05 01 06 01 07 01 08 01 09 01 10 Q901 Drain IC401 20 IC601 6 Q799 Base Q799 Drain Q719 Drain Q705 Drain Q706 Base Q706 Collector Q704 Gate IC305 5 6 7 IC302 1 IC302 24 IC302 23 IC302 19 20 21 CDT RK GK BK IC901 6 IC401 45 IC401 46 IC401 18 IC401 35 IC401 33 IC401 34 IC401 52 01 11 IC401 53 IC401 21 IC4...

Page 43: ... 45 e d i S t n e n o p m o C D R A O B N I A M 3 e d i S r e d l o S D R A O B N I A M 4 e d i S t n e n o p m o C D R A O B L O R T N O C 1 e d i S r e d l o S D R A O B L O R T N O C 2 44 ...

Page 44: ...SEP 2005 P NO 38289S0019K Printed in China ...

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