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SET-TOP BOX SERVICE MANUAL MODEL : LST-3100A CAUTION BEFORE SERVICING THE UNIT, READ THE “SAFETY PRECAUTIONS” IN THIS MANUAL. AUGUST, 2003 P/NO : 3829RVN006Q Printed in Korea...
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CONTENTS SECTION 1 ..SUMMARY SECTION 2 ..CABINET & MAIN CHASSIS SECTION 3 ..ELECTRICAL SECTION 4 ..REPLACEMENT PARTS LIST...
PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY, SUBJECT : X-RADIATION NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFAC- 1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PER- TURER’S APPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLY SONNEL COVER THE SUBJECT OF X-RADIATION.
SERVICING PRECAUTIONS CAUTION : Before servicing the STB covered by this service Electrostatically Sensitive (ES) Devices data and its supplements and addends, read and follow the Some semiconductor (solid state) devices can be damaged SAFETY PRECAUTIONS. NOTE : if unforeseen circum- easily by static electricity.
SPECIFICATIONS Television System NTSC, DTV standard (1080i, 720p, 480p, 480i) Channel Coverage Terrestrial: 2-69, Cable: 1-135 Input/Output ATSC ANT Input ANT IN (1) (ATSC-8VSB over Terrestrial or QAM over cable) ANT Loop Out Out To TV (1) DVI Output DVI-HDTV Out (1), DVI-D Single Link connector 1080i, 720p, 480p digital RGB Component Video Output Component Out (1 Set), Typical RCA type Jack connectors...
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SECTION 2 CABINET & MAIN CHASSIS CONTENTS EXPLODED VIEWS ........................2-2 1. Cabinet and Main Frame Section ...................2-2 2. Packing Accessory Section ....................2-3...
1. Open window display for Serial Communication like above. - You can use almost kinds of serial communication programs, but we send the terminal (LG Term) which is now used on our side. 2. Create “Setup-> Serial Port” like the display. (However, the port depends upon the user environment so that you need to create properly.)
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4. After completing all set-up process, press d key in the terminal and impress STB power. At this time, you should pull up the plug and then pull into the socket again. - You have another choice. When activating, please enter “klLST3100”, “ENTER” and then “F10”...
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8. In the downloadable condition, select °∞File->Send File°±. You can watch one more dis- play like above. You should find °∞ram.biz°∞ file in this new display and open it to start downloading. 9. You can see the downloading process from display and it takes about 2 minutes to com- plete.
ELECTRICAL TROUBLESHOOTING GUIDE 1. Power(SMPS) CIRCUIT (1) No 5.0VA No 5.0VA Replace the Is the D107 Normal? D107. Replace the F101. Is the F101 normal? (Use the same Fuse) Power Line of Main PCB is short Is the BD101 Replace the normal? BD101.
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(4) No 12VA (6) No VFD Is there about 13V No VFD at the IC155 pin1? Is The R123 Is there about 3.3V~5V Check or Replace Replace the R123 at the IC155 pin4? the D109 Normal? Check the IC155 Check the ‘PWR CTL Is The D107 Replace the R107 and Replace...
2. AUDIO CIRCUIT 1) NO ATSC AUDIO (1) Check IC110 and Surroundings 5V is supplied to IC110(14)? Check the Power Supply Part. Check 12.2880MHz Clock output at 12.2880MHz clock is input to IC110 (5)? Fig. 01 IC200(H5). Check 48KHz Clock ouput at IC200 48KHz clock is output from IC110 (4)? Fig.
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Fig. 01 12.2880MHz clock Fig. 02 48KHz clock Fig. 03 Data Signal Fig. 04 Analog Audio Signal...
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(2) Check IC112 and Surroundings 59V is supplied to IC112(8)? Check Power Supply Part Analog audio signal is output from Check IC112 and surroundings IC112(1, 7)? Fig. 05 (3) Check Q102, Q103, Q109, Q110 and Surroundings 9V is supplied to Q102, Q103, Check Power Supply Part Q109,Q110(3)? Analog audio signal is output from...
3) NO COAXIAL OUTPUT AUDIO 5V is supplied to Q100(3)? Check Power Supply Part SPDIF pulse is output from IC200(F3)? Check IC200 and surroundings Fig. 07 SPDIF pulse is output from Q100(1)? Check Q100, Q101 and surroundings Fig. 08 Check CN300(S6, G6) and their surroundings 3-12...
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Fig. 07 ,Digital Audio Signal Fig. 08 Coaxial Digital Audio Signal 3-13...
3. CPU (System Control) Troubleshooting Start Is Power supplied normally? Check Power : Refer to (A) Is each clock OK? Check each clock : Refer to (B) Is each reset OK at the time of Check reset circuit : Refer to (C) power- on reset? Is each chip selection OK? Check each chip selection : Refer to (D)
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Is 2.5V supplied to the pin 21 of IC109 Power Supply Check IC113 : 2.5V IC111 : 3.3V and 3.3V to the pin 9 of IC109 ? Is 3.3V supplied to the pin 37 of IC100, Power Supply Check 101 and the pin 1 of IC106, 107 ? IC111 : 3.3V Check IC100, 101, 106, 107, 109 3-15...
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Is 10MHz clock output from X101 ? Check X101 Fig. 01 Is 60MHz clock output from the pin 28 Check IC109 of IC109? Fig. 02 Fig. 01 Fig. 02 3-16...
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Is the pin 3 of IC103 reset ? IC103 Check Is the pin 4 of IC104 reset ? Fig. 03 IC104 Check Is the pin 93 of IC109 reset ? IC109 Check Is the pin 10 of IC104 reset at the IC104 Check time of power- button on? Fig.
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Is logic low pulse seen at R1060? Check IC109, 100, 101 Is logic low pulse seen at R1054? Check IC109, 106, 107 Fig. 05 Is logic low pulse seen at R1061? Check IC109, 200 Fig. 05 3-18...
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Are IIC SCL and SDA signals output from Check IC109 the pin 60, 61 of IC109 ? Fig. 06 & Fig. 07 A re IIC SCL and SDA signal input to Check IC108, IC109 the pin 1, 2 of IC108 from IC109 ? Are IIC SCL and SDA signals output Check IC108, 105, from the pin 6, 7 of IC108?
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Is RS- 232C port setup OK? Modify RS- 232C port setup (Baudrate, Parity, Data Bit, Stop Bit) Is the pin 11 of IC102 OK? Check IC109, IC102 (TxD signal) Fig. 08 Is the pin 12 of IC102 OK? Check IC109, IC102 (RxD signal) Fig.
4. VIDEO Troubleshooting Flow START No HV sync OUT? Any problem in OSD ? Any problem in main picture? Any problem in AV out? 3-21...
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FIG. 04 V- sync signal FIG. 03 H- sync signal 3-23...
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No OSD is not a problem. Check whether analog mute ON? Check DVI output. Check analog buffers. IC303 for 480i, IC302 Check whether +A12V is supplied. for component YPbPr or RGB analog Jump to (A) flow Check input stream existence. check VSB(IC203 ) block.
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FIG. 05 Input Stream to IC203 FIG. 06 Interrupt Signal 3-25...
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Check analog buffers. IC303 for 480i Jump to (A) flow 3-28...
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START Is DVI cable connected? Connect DVI cable Is Display Format front pane DVI side? Change to DVI side Use other DVI cable or Turn on the moni- Is The emitter of Q201 high volt ? tor that is connected with DVI cable. Is IC206(11) high volt ? Change the DVI chip Check IC206(57(IDCK+), 2(DE),...
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FIG. 01 DVI output at 480p FIG. 02 FIG. 03 FIG. 04 DVI output at 720p DVI output at 1080i even field DVI output at 1080i odd field 3-30...
5. ATSC/ QAM Front- End Troubleshooting Flow START Check the power lines referring Is Power supplied normally? the circuit diagram Is RF signal detected? Change channel with DTV signal (using Spectrum Analyzer) Check IC203’s output signals of Check the status of connection on PCB. DATA( Fig.
6. FRONT PANEL Troubleshooting Flow 1) If front panel board is not working START Check IC100(13), IC100(43), The IC 5V power is supplied normally? IR100(2) voltage : 5V Check Connector P101(3), P101(2), The IC -28, -24, -21.5V powers are supplied normally? P101(1) voltage : -28, -24, -21.5V Check IC100(5) clock waveform The clock #1 operates normally?
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2. OVERALL BLOCK DIAGRAM 2 ATSC NIM TUNER IC203 RF IN Tuner ATSC TP Loop Through IC105 Digital Audio EEPROM Coaxial Out (32Kx8b) 5V I2C 3V I2C Digital Audio Out Digital Audio 5V I2C Optical Out Sil 170 DVI 5V I2C IC200 I2C Hub IC201, IC202...
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3. OVERALL BLOCK DIAGRAM 3 : Video Signal : Digital Video Signal : Audio Signal : Digital Audio Signal IC203 ATSC NIM TUNER RF IN Tuner ATSC TP Loop Through IC105 Digital Audio EEPROM Coaxial Out (32Kx8b) Digital 5V I2C 3V I2C Audio Out Digital Audio...
3. AUDIO PROCESSING BLOCK DIAGRAM IC200 IC110 IC112 HA_DACLRCH Left Audio Out Low Pass AUDIO DAC HA_DACLRCK Filter (CS4340) (MC33078) HA_AUDCLKOUT Right Audio Out Left Audio Out Right Audio Out IC109 Variable Audio Out AUDIO_MUTE_CTRL (LGDT (S3C44B0X) Buffer 1102A) Variable Audio Out Q102, Q103, Q109, Q110 Digital Audio...
CIRCUIT DIAGRAM 1. POWER(SMPS) CIRCUIT DIAGRAM No Digitron appeared D107,R123,ZD102 are Defective -29VA No Power D128 is Defective 12V No Power No Power D125 is Defective BD101,R105 are Defective 30VA No Power No Power D110 is Defective D102 is Defective 3.3V No Power D105 is Defective Switching Error...
3. FRONT P.C.BOARD LOCATION GUIDE 4. POWER P.C.BOARD 3-62 3-63...
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NOTES) electricial shock. SECTION 4 REPLACEMENT PARTS LIST MODEL : LST-3100A AA1UZL(ZENITH) NSP : Not avallable as service parts. RUN DATE :13-AUGUST-03 S AL LOCA. NO. LG PART NO. DESCRIPTION SPECIFICATION REMARKS *** INDIVIDUAL PARTS *** 3110R-P020A CASE VCR LSS-2300 TOP(SKYLIFE STB)
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S AL LOCA. NO. LG PART NO. DESCRIPTION SPECIFICATION REMARKS C113 0CN1040K948 CAPACITOR,FIXED TUBULAR(High d 0.1UF D 50V 80%,-20% F(Y5V) TA C114 0CN1040K948 CAPACITOR,FIXED TUBULAR(High d 0.1UF D 50V 80%,-20% F(Y5V) TA C115 0CN2210K518 CAPACITOR TUBULA(HIGH DIELE) 220P TA26 C116...
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S AL LOCA. NO. LG PART NO. DESCRIPTION SPECIFICATION REMARKS C120 0CE477BH630 CAPACITOR,AL.ELECTROLYTIC 470UF KME TYPE 25V M FM5 BULK C122 624-085D CAPACITOR CE 47UF/50V KME (SMPS) C123 624-085D CAPACITOR CE 47UF/50V KME (SMPS) C124 624-085D CAPACITOR CE 47UF/50V KME (SMPS)
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S AL LOCA. NO. LG PART NO. DESCRIPTION SPECIFICATION REMARKS R120 0RN2701F408 RESISTOR,FIXED METAL FILM 2.7K OHM 1/6 W 1% TA26 R121 0RD1000F608 RESISTOR,FIXED CARBON FILM 100 OHM 1/6 W 5% TA26 R123 0RF0200F708 RESISTOR,VARIABLE[CARBON FILM] 0.2 OHM 1/6 W 10% TA26...