INTRODUCTION - Digital/Analog broadcasting recorder/receiver [HD/SD PERSONAL VIDEO RECORDER & RECEIVER] or PVR(Personal Video Recorder)-STB(Set-Top Box) receives the ground wave HD Digital broadcasting pro- gram /Analog NTSC or Cable broadcasting program and saves a video and audio signal at a HDD with a specific form or offers additional related services..
When servicing this product, under no circumstances should the original design be modified or altered without permission from LG Electronics Corporation. All components should be replaced only with types identical to those in the original circuit and their physical location, wiring and lead dress must conform to original layout upon completion of repairs.
SERVICING PRECAUTIONS CAUTION: Before servicing the HD/SD PERSONAL VIDEO Electrostatically Sensitive (ES) Devices RECORDER & RECEIVER WITH GEMSTAR covered by Some semiconductor (solid state) devices can be damaged this service data and its supplements and addends, read and easily by static electricity. Such components commonly are follow the SAFETY PRECAUTIONS.
EXPLODED VIEWS 1. Cabinet and Main Frame Section NOTES) THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.
ELECTRICAL TROUBLESHOOTING GUIDE 1. Power(SMPS) CIRCUIT No 3.8VA Is the F101 Replace the FR101 Normal? (Use the same ICW) Is the BD101 Replace the Normal? BD101 Is the R107 Replace the R107 Normal? Is Vcc (14V-22V) sup- Is the D102 Check or Replace plied to IC101 Pin3? normal?
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No 5VA No 30VA Is there about 5.5V Check or Replace Is the ZD152 Replace the ZD152 at the IC153 pin1? the D124 Normal? (Use the same Value) Check or Replace Check or Replace the IC153 the D126 No 12VA Is there about 14V Check or Replace at the IC151 pin1?
2. CPU(SYSTEM CONTROL) TROUBLESHOOTING Start Power is supplied normally? (A) Power check Clock signals are OK? (B) Clock check Reset signals are OK at the time of (C) Reset check power-on reset? Chip selection signals are OK? (D) CS check IIC channels are OK? (E) IIC check Interrupt signals are OK?
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(A) Power check Power Supply Check 2.5V is supplied to L101? IC954(3) : 2.5V 3.3V is supplied to IC104(37), IC105(37), Power Supply Check IC950(2) : 3.3V IC102(1), IC103(1), and IC201(3)? Power Supply Check 3.3V is supplied to IC106(14)? IC950(2) : 3.3V (B) Clock check 25MHz clock is output from X101(3)? Check X101...
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Fig.01 X101(3) : 25MHz CPU Clock Fig.03 X102(3) : 3.6864MHz UART Clock Fig.02 IC201(87) : 37.5MHz PERI Clock...
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(D) CS check Logic low pulse is seen at R138? Check IC101, 104, 105 Fig.05 Logic low pulse is seen at R140? Check IC101, IC211 Logic low pulse is seen at R144? Check IC101, IC400 Logic low pulse is seen at R143? Check IC101, IC201 Fig.05 R138(1) : Flash CS signal...
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(E) IIC check IIC SDA and SCL signals are output Check IC211 from IC211(19 & 18)? Fig.06 & Fig.07 IIC SCL and SDA signals are output Check IC101 from IC101(W17 & U15)? Fig.06 IC211(19) : 3.3V IIC SDA signal Fig.07 IC211(18) : 3.3V IIC SCL signal...
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(F) Interrupt check Logic high is input to IC101(D18) or R418? Check IC100, IC400 Logic high is input to IC101(W20) or Check IC100, CN201(7) CN201(7)? Fig.08 IC101(D18) : No Interrupt signal 3-10...
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(G) RS-232C check RS-232C port setup is OK? Modify RS-232C port setup (Baudrate, Parity, Data Bit, Stop Bit) IC204(10) is OK?(TxD signal) Check IC101, IC204 Fig.09 IC204(9) is OK?(RxD signal) Check IC101, IC204 Fig.10 Fig.09 IC204(10) : TxD signal Fig.10 IC204(9) : RxD signal 3-11...
3. ATSC/QAM FRONT_END TROUBLESHOOTING Start Check the power lines(A9V, D5V_2, Power is supplied normally(TU300)? D3.3V_2, P_30V_TU) referring the circuit diagram. RF signal is detected? Check antenna connection. (using Spectrum Analyzer) Check the Voltage between L303 and Check error signal(TU300(22)). (using Ground.
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FIG.03 TU300(36) VSB/QAM DATA Byte Clock FIG.02 TU300(27) VSB/QAM DATA Packet Clock FIG.01 TU300(28,29,30,31,32,33,34,35) VSB/QAM DATA Outputs 3-13...
4. NTSC/FRONT_END TROUBLESHOOTING Start Check the power lines(A9V, D5V_2, Power is supplied normally? D3.3V_2, P_30V_TU) referring the circuit diagram RF signal is detected? Check antenna connection. (using Spectrum Analyzer) What Voltage is between L303 and ground ? Change Q300. 5V : NO 1V( below) : YES Check NIM Tuner(TU300)’s output signal Change TU300.
5. FPGA TROUBLESHOOTING (1). NO ATSC AUDIO & VIDEO 1) Check IC801, IC960 and surroundings 3.3V is supplied to IC801?(Check C802) Check the Power Supply Part. 1.5V is supplied to IC801?(Check C812) Check IC960 and surroundings. 27MHz is output from X801? Check X801 Check the ATSC/QAM tuner part 3-15...
6. VIDEO TROUBLESHOOTING Start No HV sync OUT? What is the main picture source? Any problem in main picture? DTV or NTSC or RGB NTSC Any problem in AV out? (C1) (C2) (C2) 3-16...
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Check L400(1.8V), L401(3.3V) IC950(2) Power is supplied to IC400[HD2]? (3.3V). Video display clock(IC615(7)) is supplied Check X600 if there is sinusoidal 27MHz clock. FIG.02 to HD2? FIG.01 FIG.01 VDP clock FIG.02 Crystal 27MHz clock 3-17...
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(C2) When NTSC is main Check tuner output composite signal Check tuner block(TU300) (C615) FIG.05 power check: L602 5V Analog input: IC606 (44) Check NTSC decoder. Reference clock oscillation : X601 FIG.06 Pixel clock: 13.5MHz continuous Clock in IC606 (28). FIG.07 Hsync out: 15.7KHz negative pulse in IC606 (36).
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(C2) When RGB is main Check RGB cable is connected Connect RGB cable Check PC resolution Change resolution to 1024 x 768 Check H:CN203(2)(Fig.10 top). V : CN203(1) (FIG.10 middle), R:CN203(9), Check cable or video card G:CN203(5) ,B:CN204(4) (FIG,10 bottom) If the pin is high, check IC201(23) Check input selection is low : IC506(1) If IC203(23) is high then try power off/on.
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FIG.10 H,V and R,G,B signal FIG.12 ADC output h_sync(IC504(6600 FIG.11 ADC output clock(IC504(67)) FIG.13 ADC output v_sync(IC504(64)) FIG.14 ADC output digital data 3-23...
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Check Q501 base voltage. Check NTSC mute signal is low. Must be low. If not, check IC201 pin 47 Check NTSC encoder pixel clock: Check HD-II NTSC encoder part. IC605(13) FIG.15 Check power:IC604(8); +5V IC604(4) ; –5V Check NTSC analog output buffer part Check composite: FIG.16 top, Input: IC604(3,5) Output: IC604(1,7) 3-24...
7. AUDIO TROUBLESHOOTING (1) NO ATSC AUDIO 1) CHECK IC400 AND SURROUNDINGS Is FPGA Part OK? Go to FPGA Troubleshooting Flow(1) 1.8V & 3.3V are supplied to IC400? Check the Power Supply Part. Data is input from TU300 to IC400(A11, Check Tuner Part.
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Fig.01 Data output from R424 Fig.02 3.072MHz clock from FB401 Fig.03 48KHz clock from R421 3-30...
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5. NO ATSC AUDIO 2) CHECK MSP4448G AND SURROUNDINGS 5V is supplied to IC701(10, 16, 49, 63)? Check Power Supply Part 8V is supplied to IC701(31)? 12V is supplied to IC703(1)? 18.432MHz Clock is input to IC701(54, Check Power Supply Part 55)? Data pulse is input to IC701(6)? Check X701...
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6. AUDIO TROUBLESHOOTING 3) Check IC702 and Surroundings 9V is supplied to IC702(8)? Check Power Supply Part Analog audio signal is output from Check IC702 and surroundings IC702(1, 7)? 6. AUDIO TROUBLESHOOTING 4) Check Output Jack and Surroundings Check Q702, Q703, Q704, Q705, JA600 and their surroundings 3-32...
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6. AUDIO TROUBLESHOOTING (2) No NTSC Audio ATSC Audio is OK? Go back to symptom #1 SIF signal is input to the Base of Q302? Check TU300 SIF signal is input to IC701(50)? Fig.05 Check Q302 Analog audio signal is output from Check IC701 and surroundings.
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6. AUDIO TROUBLESHOOTING (3) No SPDIF Out for ATSC ATSC Audio is OK? Go back to symptom #1 SPDIF pulse is output from R423? Fig.06 Check IC400 and surroundings. SPDIF pulse is output from IC704(4)? Check IC704 and surroundings. 5V is supplied to JA701(2)? Check Power Supply Part.
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6. AUDIO TROUBLESHOOTING (4) No SPDIF Out for ATSC ATSC Audio is OK? Go back to symptom #1 ATSC SPDIF is OK? Go back to symptom #3 NTSC Audio is OK? Go back to symptom #2 Analog audio is output from IC701 Check IC701.
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6. AUDIO TROUBLESHOOTING (5) No External Audio Video is OK? Check External Video Input Audio is output form pin 6 and 8 of CN203 Check CN203 and surrounding 11 pin is connection Cable OK? Check 11 pin Connection Cable Junction Board(6870R3815HA) is OK? Check Junction Board(6870R3815HA) External A/V Test Card(IP card) is OK? Check External A/V Test Card...
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6. AUDIO TROUBLESHOOTING (6) No SPDIF for External Audio External Audio is OK? Go back to symptom $5 ATSC SPDIF is OK? Go back to symptom #3 Analog audio is input to IC701(35, 36)? Go back to symptom #6 18.432MHz clock is output from Check IC701.
5. BACK PLANE PRINTED CIRCUIT DIAGRAM 6. POWER PRINTED CIRCUIT DIAGRAM (TOP VIEW) LOCATION GUIDE NOTES) Warning NOTES) Parts that are shaded are critical NOTES) With respect to risk of fire or NOTES) electricial shock. (BOTTOM VIEW) 3-69 3-70...