LG Gold Star CF20G20R free download

File name Goddstar_CB21T20S_PC-81A.pdf

NO RASTER CHECK +B at D821 cathode Normal Abnormal Is the voltage at pin37 & 12 of IC501 8V? Yes No Check &replace IC501 No Check &replace IC501 Check pin40 of IC501(H-out) Yes Check Q402 collector waveform Yes Check T401 & each pin voltage No Check &replace IC501 Yes Is the voltage at pin37 & 12 of IC501 8V? Check FUSE of AC line No Check the in/out of IC841 No 254~380V Check u-COM pin1 low? No Check /replace Q802 Check the voltage of pin9 OK Check the voltage of C805 Open Check /replace Fuse,DB801,IC801 0V Check /replace DB801,R851 Check /replace D804,IC801,R801,802 NO TELETEXT Check the voltage of IC701 pin19 OK 0V Check CVBS signal at IC701 pin9 Check 5V Supply Line of IC701 OK OK Check IC701& IICBus Line Not OK Check / Replace Q701, X701, & IC501 NO RASTER / SOUND OK Check the Heater voltage of CPT (6 6.5Vrms) OK Not OK Check HV, Screen voltage of CPT Not OK OK Check Ik Current of IC501, pin18 Not OK OK Check the Heater pulse of FBT T701 Not OK Check/Replace CPT Board Components Check FR704, FR901 P302, & P903 Check FBT T701 Check FBT T701 Check IC501, ZD904 P501, & P902 NO SOUND / PICTURE OK Check the voltage of SMPS 25V at pin5 of IC601 Abnormal Normal(20~25V) Check/Replace of FR824,D824,FR601 Check the voltage swing of pin2 of IC501 Check demodulated signal of pin15 of IC501 Check/Replace IC501 Check demodulated of input pin of IC601 Check/Replace IC01 Check/Replace IC601 NO PICTURE / NO SONUD Is any OSD displayed? No Yes OK Check IC01 pin30,31,32 (R,G,B) Not OK Check IC01 pin9,10 (V-Sync, H-Sync) Check IC01 pin36,37 (XLC, EXLC) & IC01 Check 5V, 33V & IIC Bus Line Not OK Does the Auto-program operate properly. Not OK Store in manual-program MENU Check 5V, 33V & IIC Bus Line of TUNER OK Check / Replace TUNER, IC501 Not OK Is the CVBS signal OK. ( IC501 pin6 ) OK Check CVBS singal Line & IC501 Not OK Check R,G,B signal at IC501 pin19,20,21 OK Check / Replace CPT Board component Go to NO SOUND / PICTURE OK Yes Check receiving system in MENU & excute Auto-program. ADJUSTMENT Y Safety Precautions 1. It is safe to adjust after using insulating transformer between the power supply line and chassis input to prevent the risk of electric shock and protect the instrument. 2. Never disconnect leads while the TV receiver is on. 3. Don't short any portion of circuits while power is on. 4. The adjustment must be done by the correct appliances. But this is changeable in view of productivity. 5. Unless otherwise noted, set the line voltage to 230Vac!10%, 50/60Hz. Model System Tuner P/N Marker AGC Voltage Model System Tuner P/N Marker AGC Voltage CKPAL/SECAM-B/G,D/K 6700VPF005B LGEC 2.3! 0.1V CBPAL-B/G 6700VPF005B LGEC 2.3! 0.1V CLPAL/SECAM-B/G,LL' 6700VPF005A LGEC 2.3! 0.1V CIPAL-I/I 6700VPF005A LGEC 2.1! 0.1V Y Test Equipment required 1. Multimeter (volt meter) 2. Oscilloscope : RF AGC (Automatic Gain Control) Adjustment Test Point Adjust : AGC TP (J05) : Remote Control : Screen Voltage Adjustment Test Point Adjust : RK (