LG 775FT, Service Manual

Page 1: ...COLOR MONITOR SERVICE MANUAL CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL MODEL 775FT FB775G EA CHASSIS NO CA 113 FACTORY MODEL FB775G ...

Page 2: ...5 4 x 244 1 mm 12 81 x 9 61 Preset Image Size 310 x 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 90 Non condensing 5 3 Altitude 5 000 m 6 DIMENSIONS with TILT SWIVEL Width 415 0 mm 16 34 inch Depth 439 0 mm 17 28 inch Height 43...

Page 3: ...sign Soldering must be inspected for the cold solder 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 ...

Page 4: ...4 41 1 14 2 70 0 57 V 85 07 11 755 11 178 0 577 0 056 0 503 0 018 H 68 677 14 561 10 836 3 725 1 016 2 201 0 508 V 85 00 11 764 11 182 0 582 0 044 0 524 0 014 Mode H V Sort 1 2 3 4 Dot Clock MHz Horizontal Frequency kHz Vertical Frequency Hz Horizontal etc µs Vertical etc ms Sync Polarity Frequency Total Period E Video Active Time A Sync Duration D Blanking Time B Back Porch F Front Porch C 640x48...

Page 5: ...e stand by suspend or power off mode its color changes to orange and if abnormal or damaging circuit turns out orange blink 3 SET Button This button to enter a selection in the on screen display 4 OSD Select Adjustment Use for selecting highlighting an OSD icon and adjusting level of the selected menu 5 OSD Button This button to enter or exit the on screen display OSD SET See Front Control Panel P...

Page 6: ...WIRING DIAGRAM 6 P501 P201 P405 P301 P302 G2 P702 P701 T1 P402 P902 S S Signal Cable AC Socket FBT ...

Page 7: ... Sig V Sync Sig I2C DATA SDA I2C CLOCK SCL VIDEO LM1269 PRE AMP IC302 Signal Cable R G B VIDEO LM2469 LM2480 CUT OFF IC IC304 MAIN AMP IC303 5V 5V H V Sync Processor IC701 TDA4841 V OUT IC601 TDA4866J H OUT Q706 H Linearity Correction DC DC Converter X RAY Protection Circuit FBT T701 Dynamic Focus Circuit Auto Beam Limit Vertical Blanking Brightness Control 160V 40V 400V STEP UP 15V D D Feed Back ...

Page 8: ...ts operating mode and offers the controlled data H size H position V size etc 4 The controlled data of each mode is stored in itself 5 User can adjust screen condition by each OSD function The data of the adjusted condition is stored in EEPROM IC402 6 Horizontal and Vertical Oscillation This circuit generates the horizontal pulse and the vertical pulse by taking the H and V sync signal This circui...

Page 9: ... deflection yoke of the CRT 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 contrast signal from the Micom IC401 17 Video Output Amp Circuit This circuit amplifies the video signal which comes from the video pre amp circuit and amplified it to applied the CRT cathode ...

Page 10: ...RL PWM TILT command 7 Adjust tilt as arrow keys to be the best condition 8 DIST ADJ BALANCE command 9 Adjust parallelogram as arrow keys to be the best condition 10 Adjust balance of pin balance as arrow keys to be the best condition 11 DIST ADJ FOS ADJ command 12 Adjust V SIZE as arrow keys to 230 2mm 13 Adjust V POSITION as arrow keys to center of the screen 14 Adjust H SIZE as arrow keys to 310...

Page 11: ...ABL command 22 Adjust ABL to 32 1FL of the luminance 23 After push the ENTER key and COMMAND PRESET EXIT Y Yes command 24 Exit from the program 4 Input EDID Data 1 Display color 15 0 cross hatch pattern at Mode 4 2 EEPROM Write EDID command and confirm EDID Write OK message of monitor 3 Exit from the alignment program 4 Power switch OFF ON for EDID data save 5 Adjustment for Focus 1 Set the Bright...

Page 12: ...IN FUSE F901 TROUBLE IN IC901 TROUBLE IN D941 D942 D951 D961 D962 D971 TROUBLE IN Q903 Q952 Q951 Q942 Q941 CHECK FUSE OK CHECK C908 VOLTAGE AC120V 160VDC AC220V 304VDC NO YES YES YES YES NO NO NO CHECK IC901 PIN 5 WAVEFORM SQUARE WAVE COMES OUT CHECK D941 D942 D951 D961 D962 D971 VOLTAGE ...

Page 13: ... 1 2 3 CHECK IC303 PIN 4 80V PIN 8 12V TROUBLE IN P302 5V LINE TROUBLE IN PC SIGNAL P301 SIGNAL CABLE TROUBLE IN IC302 TROUBLE IN P303 12V LINE 80V LINE TROUBLE IN IC303 NO YES NO NO YES YES YES YES NO NO CHECK R G B CATHODE VOLTAGE TROUBLE IN R341 R343 R331 R333 L311 L313 D307 D312 TROUBLE IN CRT SOCKET YES NO ...

Page 14: ...ECK POWER INDICATOR GREEN or AMBER CHECK D712 ANODE 157V CHECK G1 VOLTAGE 55V 150V TROUBLE IN D712 TROUBLE IN Q799 DPM MODE NO H and or V SYNC AMBER NO GREEN YES NO CHECK CDT HEAT VOLTAGE 6 3V TROUBLE IN D941 Q942 Q941 YES NO TROUBLE IN CDT YES ...

Page 15: ...VERTICAL LINE CHECK Q706 CHECK B VOLTAGE 50V CHECK T701 FBT PIN 2 31KHZ 60V 69KHZ 140V CHECK Q701 COLLECTOR WAVEFORM TROUBLE IN Q706 TROUBLE IN 50V LINE TROUBLE IN Q719 Q720 D710 TROUBLE IN Q701 TROUBLE IN T701 P701 NO NO YES YES YES YES NO NO 0V T ...

Page 16: ...CHECK L703 TROUBLE 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 44 9K 45K 48 9K 49K 57 9K 58K 65 9K 66K 70K Cs1 L L H L H L H Cs3 L L L H H H H Cs2 L H H L L H H ...

Page 17: ...ECTION ONE HORIZONTAL LINE CHECK IC601 PIN 3 15V CHECK IC601 PIN 7 40V CHECK IC701 PIN 12 13 TROUBLE IN R603 15V LINE TROUBLE IN HIGH VOLTAGE OUT CIRCUIT FBT D721 R606 TROUBLE IN IC701 TROUBLE IN IC601 V CIRCUIT NO NO YES YES YES NO 3V ...

Page 18: ...BLE IN IC601 PIN8 V FBP T701 40V LINE H FBP TROUBLE IN IC302 IC301 TROUBLE IN IC301 IC302 NO YES DC 5V YES YES YES NO NO NO Pin 5 5V Pin 10 5V H V 5V H V CHECK IC301 B 5V CHECK IC301 PIN 12 WAVEFORM ENTER BUTTON MUST BE PRESSED CHECK IC301 PIN 5 10 WAVEFORM CHECK IC301 PIN 13 14 15 ...

Page 19: ...ECK PC PC IS NOT GOING INTO DPM OFF MODE TROUBLE IN X401 TROUBLE IN IC401 MICOM TROUBLE IN Q941 Q942 Q951 Q952 TROUBLE IN PC OFF MODE FAILURE INPUT H V SYNC SIGNAL H V SYNC NO OFF MODE NO NO NO NO DPMF 0V DPM TABLE Mode Item NORMAL STAND BY SUSPEND OFF DPMF H H H L LED GREEN AMBER AMBER AMBER DPMS H L L L YES YES SEE DPM TABLE YES YES 5V 24MHz ...

Page 20: ...CK Q953 COLLECTOR VOLTAGE CHECK P902 CHECK RL901 TROUBLE IN IC401 MICOM TROUBLE IN Q953 TROUBLE IN P902 TROUBLE IN RL901 TROUBLE IN TH901 DEGAUSSING COIL NO DEGAUSSING DC 15V NO NO NO NO YES YES YES YES DEGAUSS ON THE OSD MENU MUST BE PRESSED ...

Page 21: ... TILT NO ROTATION TROUBLE IN IC401 MICOM TROUBLE IN 15V LINE 6 3V LINE TROUBLE IN Q501 Q503 TROUBLE IN P501 TILT COIL D501 NO YES YES YES CHECK 15V LINE AND 6 3V LINE CHECK Q503 EMITTER VOLTAGE NO NO CHECK IC401 PIN21 WAVE FORM ...

Page 22: ...EXPLODED VIEW 2 5 6 12 11 14 7 B A 8 9 10 15 13 16 16 1 4 OS D SE T 18 17 19 20 3 13 a b c b 22 ...

Page 23: ...FB775G 031 CKD Brazil only TILT SWIVEL ASSY SFB775B T032 B029 HIPS 85964 CKD SCREW ASSY PHP 5 20 FZMY GW18 NEW TYPE COIL DEGAUSSING GET D COIL 0 5 130TS 1410 WITH PURITY FB770G PWB PCB ASSEMBLY SUB FB775G KXLVED CONTROL TOTAL BRAND CA 109 PWB PCB ASSEMBLY SUB FB775G KQBRES CONTROL TOTAL BRAND CA 113 Brazil only FBT FLY BACK TRANSFORMER 1054A CB777G LG PHILIPS 17 SOCKET CIRC POWER BAE EUN AC UNIVER...

Page 24: ...15 100PF 50V K B TR C407 0CK1010K515 100PF 50V K B TR C408 0CK1040K945 0 1UF 50V Z F TR C409 0CC5600K415 56P 50V J NP0 TP C410 0CK1010K515 100PF 50V K B TR C411 0CK1040K945 0 1UF 50V Z F TR C412 0CK1040K945 0 1UF 50V Z F TR C413 0CK1040K945 0 1UF 50V Z F TR C501 0CE106CF638 10UF SHL SD 16V M FM5 TP 5 C510 0CE225CK638 2 2UF SHL SD 50V M FM5 TP 5 C511 0CE106CF638 10UF SHL SD 16V M FM5 TP 5 C599 0CE2...

Page 25: ... ROHM KOREA D314 0DS124409AA 1SS244 TP ROHM KOREA D315 0DS124409AA 1SS244 TP ROHM KOREA D316 6210TCE003J BAS2550T BO SUNG 2550MM AXIA D317 0DS141489AB 1N4148 TP GRANDE DO 34 500MW D401 0DS141489AB 1N4148 TP GRANDE DO 34 500MW D402 971 0016 TIN HDC 0 60H D501 0DS141489AB 1N4148 TP GRANDE DO 34 500MW D511 0DS141489AB 1N4148 TP GRANDE DO 34 500MW D512 0DS141489AB 1N4148 TP GRANDE DO 34 500MW D701 0DS...

Page 26: ... L705 6140TBZ026C DR15 18 C9 8 100UH 0 1 30MM L901 6200TLS004B SQE2424 15MH 0 55MM 70T CB77 DATE 2002 05 22 S AL LOC NO PART NO DESCRIPTION SPECIFICATION Q501 0TR320209AA KTC3202 Y KTC1959 TP KEC TO Q502 0TR127009AA KTA1270 Y KTA562TM TP KEC T Q503 0TR319809AA KTC3198 Y KTC1815 TP KEC TO Q510 0TR319809AA KTC3198 Y KTC1815 TP KEC TO Q511 0TR320509AB KTC3205 Y KTC2236A TP KEC T Q512 0TR127509AC KTA1...

Page 27: ...101A609 1 OHM 1 2 W 7 0 5 TA52 R515 0RD1502Q609 15K 1 4W 3 5 TA52 DATE 2002 05 22 S AL LOC NO PART NO DESCRIPTION SPECIFICATION R597 0RD3902Q609 39K 1 4W 3 5 TA52 R598 0RD5601Q609 5 60K 1 4W 3 5 TA52 R599 0RD0202Q609 20 1 4W 3 5 TA52 R601 0RD1001Q609 1K 1 4W 3 5 TA52 R602 0RD1001Q609 1K 1 4W 3 5 TA52 R603 0RN0390H609 0 39 1 2W 5 TA52 R604 0RD0101A609 1 OHM 1 2 W 7 0 5 TA52 R605 0RD0102A609 10 OHM ...

Page 28: ... 5 TA52 R906 0RD6200Q609 620 1 4W 3 5 TA52 R908 0RN0220H609 0 22 1 2W 5 TA52 R910 0RX4702J609 47K OHM 1 W 5 TA52 R925 0RB0120K607 0 12 OHM 2 W 5 TA62 R941 0RN0220H609 0 22 1 2W 5 TA52 R944 0RD4700A609 470 OHM 1 2 W 7 0 5 TA52 R945 0RD4701Q609 4 70K 1 4W 3 5 TA52 R951 0RN0910H609 0 91 1 2W 5 TA52 R952 0RD4702A609 47K OHM 1 2 W 7 0 5 TA52 R953 0RX4700J609 470 OHM 1 W 5 TA52 R954 0RD4701Q609 4 70K 1 ...

Page 29: ...nfiguration 1 9 1 2 3 4 5 6 7 8 9 V 3 GND IN V 3 OUT V 2 OUT V 1 OUT V 2 IN V 1 IN VCC VBB LM2469 Monolothic Triple 9nS high Gain CRT Driver Connection Diagram 1 9 M24C08 Serial I2C BUS EEPROM SYMBOL E0 E2 SDA SCL WC Vcc Vss DESCRIPTION Chip Enable Input Serial Data Address Input Output Serial Clock Write Control Supply Voltage Ground 1 PSDIP8 BN 0 25mm Frame 8 1 1 SO8 MN 150mil Width TSSOP8 DW 16...

Page 30: ... 31 SCHEMATIC DIAGRAM ...

Page 31: ... 33 CIRCUIT BOARD 4 MAIN BOARD Solder Side 2 CONTROL BOARD Solder Side ...