Panasonic TH-37PX50U Technical Manual
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- Service manual (316 pages) ,
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Summary of Contents for Panasonic TH-37PX50U
- Page 1 Technical Guide Plasma Training Course TH-37PX50U, TH-42PD50U, TH-42PX50U, TH-42PX500U, TH-50PX50U, TH-50PX500U GP8DU and GPH8DU Chassis Troubleshooting Panasonic Services Company National Training...
- Page 2 "HDMI, the HDMI logo and High-Definition Multimedia Interface are trademarks or registered trademarks of HDMI Licensing LLC." BBE, the BBE logo, Sonic Maximizer and High Definition Sound are registered trademarks or trademarks of BBE Sound, Inc. Copyright © 2005 by Panasonic Services Company All rights reserved. Unauthorized copying and distribution is a violation of law.
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Page 3: Table Of Contents
Table of Contents Objective ........................1 Specifications (Models Comparison) ................2 Safety Precautions ......................3 TH-42PD50U Board Description and Part Numbers ........... 4 TH-42PX500U Board Description and Part Numbers ..........5 TH-50PX500 Board Description and Part Numbers............ 6 Power Supply Outline for 42”and 50” Models ............7 Standby Circuit...................... - Page 4 SU And SD Board Shift Registers ................35 SS Board Explanation....................37 SS Board Schematic ....................38 SS Board Waveform ....................38 TH-42/50PX500U ......................40 Power LED Flashing timing chart ................40 SOS Detection Circuits ....................41 SOS Detect (D Board).................... 41 SOS Detect (DG Board)..................
- Page 5 Contents of adjustment mode ................56 Internal Pattern Generator ..................57 Cable Diagnostic Screen .................... 57 Adjustments ........................ 58 Driver Set-up ......................58 Initialization Pulse Adjustment ................59 Drive Waveform ....................... 59 P.C.B. (Printed Circuit Board) exchange procedure ..........60 Adjustment Volume Locations...................
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Page 6: Objective
Objective This technical guide was prepared with the following objectives in mind: • Provide the servicer with a brief overview of the concepts of operation for new circuits employed in this line of Plasma models • Provide drawings with emphasis on signal path to simplify the task of signal tracing and locate the cause of a defect •... -
Page 7: Specifications (Models Comparison)
Specifications (Models Comparison) Features TH-42PD50U TH-42PX500 TH-50PX500 Resolution 852x480p 1024 x 768p 1366 x 768p Altitude 2400m 2400m 2400m Contrast 4000:1 3000:1 3000:1 Input Signal 720p 720p 720p 1080i 1080i 1080i 480p 480p 480p 480i 480i 480i PC Input Input Terminal (Video Input) Video 1 S2/RCA (Rear) -
Page 8: Safety Precautions
Safety Precautions Please follow these general guidelines before servicing the models mentioned in this technical guide. 1. While servicing, please observe the original lead dress. If a short circuit is found, replace all the parts that have been overheated or damaged by the short circuit. -
Page 9: Th-42Pd50U Board Description And Part Numbers
TH-42PD50U Board Description and Part Numbers Figure 1 Board Board Description Board Part Number Name Power Supply TNPA3570 DC-DC Converter, Power SOS TNPA3620 Audio Power TNPA3643 AV Terminal, AV Switch TNPA3598AB ATSC Interface TNAG156 HDMI Interface TNPA3626 Digital Signal Processor TNPA3625AF Speaker out, Audio AMP TNPA3621AB... -
Page 10: Th-42Px500U Board Description And Part Numbers
TH-42PX500U Board Description and Part Numbers Figure 2 Board Name Board Description Board Part Number Power Supply ETXMM563MDK DC-DC Converter, Power SOS TNPA3620 Audio Power, Fan control TNPA3643AD AV Terminal, AV Switch TNPA3598 ATSC Interface TNAG157S HDMI Interface TNPA3626 Digital Signal Processor TNPA3625 Speaker out, Audio AMP TNPA3621... -
Page 11: Th-50Px500 Board Description And Part Numbers
TH-50PX500 Board Description and Part Numbers Figure 3 Board Name Board Description Board Part Number ATSC Interface TNAG157S AV Terminal, AV Switch TNPA3598 DC-DC Converter, Power SOS TNPA3620 Speaker out, Audio AMP TNPA3621 Digital Signal Processor TNPA3625AB HDMI Interface TNPA3626 Audio Power, Fan control TNPA3643AD Data Driver (Up Left) -
Page 12: Power Supply Outline For 42"And 50" Models
Power Supply Outline for 42”and 50” Models Figure 4 The PF board of the older Plasma Television models is now incorporated into the P board of the GPH8DU chassis. The function of the line filter is to block incoming noise from the AC outlet to the unit and outgoing noise from the unit to the AC outlet. -
Page 13: Standby Circuit
Standby Circuit Figure 5 The diode D602 and the transformer T501 are used to develop the STB5V supply. The STB5V is applied to pin 5 of the Power control IC MC701 and pin 1 of the Power Control IC MC501 (Use hot ground to measure voltage on MC501). (See Fig. 5.) Figure 6... - Page 14 Instead of a standby power switch, as it shows in the diagram, the TV has a jumper wire on the “S” board that connects pin 8 of the connector P12 to ground. As a result the transistors Q553 and Q554 turn on, allowing the STB5V to be applied to the D and the DG-board via pin 10 of the connector P25.
- Page 15 Figure 8 The power control IC, MC701, upon receiving the “F.STB ON” voltage, outputs the “PC PFC ON” control signal at pin 20. This turns on the photocoupler PC503 to provide a low to pin 2 of the “STB Power Control” IC, MC501. MC501 outputs the “relay ON” control signal to activate the relay K601.
- Page 16 The DC voltage from the rectifier is converted to 395Vdc by the “Power Factor Control” circuit to improve the power ratio. This DC voltage is applied to three different circuits; the Vsus, the Vda and the Low Voltage (F STB 14V, 15V, and 12V) power supplies. During standby operation, both the Vsus and the Vda power supply circuits are off.
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Page 17: Power On Operation
Power On Operation Figure 11 The momentary connection of the power switch to ground supplies a low to the base of Q4001 (DG board) to turn it on. When Q4001 is on, a low is provided to pin 86 (Key scan 3) of the microprocessor IC4005. - Page 18 Upon receiving the power on command, pin 21 of IC4005 (Tuner Main ON) goes high and pin 115 (Panel STB ON) goes low. Pin 21 is connected to pin 28 of the connector PA20 via pin 1 of the connector DG20. The high at pin 21 is the control signal used to turn on the circuit that generates the SUB 3.3V, the Main 3.3V, the Main 5V, and the Main 9V sources of the PA board.
- Page 19 The high command at pin 17 of connector P25 is applied to pin 18 of MC701 of the P board. Pin 11 switches from 5V to 1.3V, and pin 12 from 15V to 0V. The 1.3V at pin 11 causes Q551 to turn on and output 5V. The 5V is applied to pin 22 of the “Drive Voltage Oscillator”...
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Page 20: Power Supply Connections
Power Supply Connections P Board Figure 14 The P board houses the main power supply of the unit. All voltages originate from this board. The connector information is to be used for troubleshooting purposes. -
Page 21: Pa Board
PA Board Figure 15 The PB board utilizes voltages obtained from the P board to create lower and higher voltages for use in different sections of the unit. The connector information can prove useful when troubleshooting. -
Page 22: Pb Board
PB Board Figure 16 The PB board contains voltage regulators that power the Audio circuit (Z board) and the fans. The connector information is to be used for troubleshooting purposes. -
Page 23: Th-42Px500U Block Diagram
TH-42PX500U Block Diagram Figure 17 The DV board processes HDMI or DVI input signals. The HDMI IF receiver converts the digital signal into parallel Y, U, V data and outputs it to the DG board for video selection and processing. GP8HD series plasma panels incorporate a Set Top Box that is designed to receive NTSC and ATSC television broadcast. - Page 24 It also processes the JPEG data of the SD and PC cards used for viewing pictures. Photo-viewer data from the G and GS boards are input to the DT board and converted to analog luminance and chrominance signals. Analog Television and Photo-viewer signals are output to the H board and selected like any other source.
- Page 25 The SU and SD boards are demultiplexer boards that are responsible for converting serial data output of the SC board into parallel data to drive the panel. The SS board is responsible for the generation of the sustain pulses. Sustain pulses are used to initialize and control the brightness of the screen.
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Page 26: Th-42Px50U Block Diagram
TH-42PX50U Block Diagram Figure 18 The DV board processes HDMI or DVI input signals. The HDMI IF receiver converts the digital signal into parallel Y, U, V data and outputs it to the DG board for video selection and processing. GP8HD series plasma panels incorporate a Set Top Box that is designed to receive NTSC and ATSC television broadcast. - Page 27 Analog Television signals are output to the H board and selected like any other source. Digital television signals (Y, Pb, Pr) are output to the DG board for video selection and processing. The K board contains the optical sensor used for CATS (Contrast Automatic tracking System).
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Page 28: Th-42Pd50U Block Diagram
TH-42PD50U Block Diagram Figure 19 The DV board processes HDMI or DVI input signals. The HDMI IF receiver converts the digital signal into parallel Y, U, V data and outputs it to the DG board for video selection and processing. GP8HD series plasma panels incorporate a tuner designed to receive NTSC and ATSC television broadcast. - Page 29 The K board contains the optical sensor used for CATS (Contrast Automatic Tracking System). It also contains the Remote IR sensor and the power LED. The unit contains two video inputs, two component inputs, and a PC input (depending upon the model) that are directly connected to the main switch of the H board. The H board selects and outputs, to the DG board, the main video and sub video signals for display on the screen.
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Page 30: Video Input Selection Block Diagram
Video Input Selection Block Diagram Figure 20 The H board contains the Video inputs 1, 2, and 3, Component Video Inputs 1 and 2, and the Program Out jacks. All the Audio/Video input signals are applied to this board for selection. There are two input selection ICs on this board; IC2602, which selects the video input signals and IC2605, which selects the audio input signals. -
Page 31: Audio Input Selection Block Diagram
Audio Input Selection Block Diagram Figure 21 IC2605 of the H board handles the audio selection of all inputs. Audio signals from the digital tuner and the HDMI receiver board (DV board) pass through the DG board and enter IC2605 of the H board via the connector H2/DG2. The selected audio signals are output to the DG Board without alteration. -
Page 32: Atsc, Sd And Pc Card Input Signal Flow
ATSC, SD and PC Card Input Signal Flow Figure 22 The ATSC interface (DT board) processes the ATSC, NTSC, and QAM television signals. It also processes the Photoviewer (JPEG) data of the SD and PC cards. The composite, luminance and chrominance, or component video signals of the DT board are output to the DG board via the connector DT12/DG22. -
Page 33: Dg Board Block Diagram
The DT board contains the host identification number and stores the POD identification number of the cable service provider. It also processes the JPEG data of the SD and PC cards used for viewing pictures. Photoviewer data from the G and GS boards are input to the DT board via the connectors DT10 and DT05. - Page 34 The Main and sub video output of the H board are provided to the DG board via the connector H2/DG2. The input signals can be in any of the three formats: Video, Y/C, or Y, Pb, Pr.
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Page 35: Signal Process Circuit
Signal Process Circuit Main Picture Signal Flow Figure 24 On the DG- Board, the main Y/V, Pb/C, Pr signals are converted to digital data by an analog to digital (A/D) converter circuit located inside the Global Core IC, IC4018 (ADV7403). The comb filter in IC4018 converts the composite video signal of the main picture to Y and C (luminance and chrominance) separated video signals. -
Page 36: Rgb Processor
RGB Processor Figure 25 The digital TV and HDMI data are input directly to this integrated circuit. By avoiding digital to analog and analog to digital conversion of those signals, the picture information remains in its original form. As a result picture quality is pure, and free from noise. -
Page 37: D Board Block Diagram
D Board Block Diagram Figure 26 The output of the LVDS transmitter of the DG board is provided to the D board via the connector DG5/D5. IC9500 of the D board contains a LVDS receiver that converts the RGB data to its original form. In this IC, the customer and panel related OSD data are mixed with the video. -
Page 38: C1 Board Block Diagram
C1 Board Block Diagram Figure 27 There are four data drive boards in the TH-42PX500U HD plasma display television. Due to their physical location and characteristics, they divide the screen into four equal quadrants as indicated in the picture on the right. Figure 28a Each data drive board contains four sockets for the connection of the panel’s... -
Page 39: Sc Board Explanation
SC Board Explanation Figure 29 The SC Board consists of buffers and drivers used to generate the scan signals for the PDP panel. The buffers provide isolation between the D board and the drivers. Connector SC20 provides the drive voltages (140V, 100V and 18V) as well as the trigger signals to switch the FET transistors. -
Page 40: Sc Board Waveform
SC board Waveform Figure 30 SU And SD Board Shift Registers Figure 31... - Page 41 After the scan waveform is developed on the SC Board, it is applied to the SU and SD boards for de-multiplexing. The signal is input to a series of shift registers inside the PDP scan driver IC. The figure above shows an example of the de-multiplexing circuit. There are six driver ICs on the SU board and six on the SD board.
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Page 42: Ss Board Explanation
SS Board Explanation Figure 32 After the video signal is processed on the D board, the sustain and erase pulses are output to the SS board. The erase pulse is output at the beginning of each scan period. The pulse is applied to the SS2 and SS3 boards to remove the previous charge from the upper and lower sections of the display panel. -
Page 43: Ss Board Schematic
SS Board Schematic Figure 33 SS Board Waveform Figure 34... - Page 44 The Sustain pulse is developed using a similar circuit as the Scan Pulse. A series of specifically timed pulses are applied to FET drivers creating the distinctive sustain pulse. The drivers switch the voltages (150V, 155V and 175V) at selected intervals determined by the D board.
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Page 45: Th-42/50Px500U
TH-42/50PX500U Power LED Flashing timing chart The unit is equipped with a self-protection circuit that places it in standby when there is an abnormality with one or more of the Power Supply circuits. The faulty circuit may be easily identified by counting the number of flashes emitted by the power LED located in front of the unit. -
Page 46: Sos Detection Circuits
SOS Detection Circuits SOS Detect (D Board) The GPH8DU chassis have several protection circuits that are designed to protect the receiver from major damage. The MPU IC9003 of the D board is used to detect and store the history of abnormalities that may be caused by a defect in certain sections of the unit. -
Page 47: Sos Detect (D And Pa Board)
SOS Detect (D and PA Board) Figure 38 The SOS detection circuits of the standard definition model TH-42PD50 is similar to the one used in the high definition models. They are monitored by two microprocessors, IC4005 of the DG board and IC9003.of the D board. IC4005 of the DG board monitors for an abnormality detected on the PA and the PB boards. -
Page 48: Pa Board Sos Detection Circuits
PA Board SOS Detection Circuits Over-Voltage Detection of Main Voltage (10 Blinks) Figure 39 The transistor Q5644 monitors the MAIN_3.3V, MAIN_5V, MAIN_9V, and MAIN_2.5V lines. If any of these supply voltages becomes excessive, the inline zener diode goes into conduction and turn on transistor Q5644. As a result, a voltage drop appears at the base of Q5641, causing it to turn on and output a high to pin 111 of the MPU, IC4005, to trigger the SOS condition. -
Page 49: Short Circuit Detection Of Main Voltage (10 Blinks)
Short Circuit Detection of Main Voltage (10 Blinks) Figure 40 The transistor Q5642 monitors the MAIN_9V, MAIN_2.5V, and MAIN_5V lines. If any of these supply lines develop a short circuit, transistor Q5642 goes into conduction and applies a high to pin 111 of the MPU, IC4005, triggering an SOS condition. -
Page 50: Short Circuit Detection Of Sub-Voltage (10 Blinks)
Short Circuit Detection of Sub-voltage (10 Blinks) Figure 41 The transistor Q5641 monitors the F_STB14V, SUB3.3V, SUB9V-1, BT30V and SUB5V lines. If any of these supply lines develop a short circuit, transistor Q5641 goes into conduction and applies a high to pin 111 of the MPU, IC4005, triggering an SOS condition. -
Page 51: Other Sos Detection Circuits
Other SOS Detection Circuits SOS Detect (P, SC, and SS Board) Figure 42 This drawing is used to verify an SOS condition that may have originated from the P, SC, or SS Board. The connector information should be used for troubleshooting purposes. -
Page 52: P Board Sos Detection
P Board SOS Detection Figure 43 This drawing is used to verify an SOS condition that may have originated from the P Board. The connector information should be used for troubleshooting purposes. The switched voltages of connector P23 and P5 are monitored on the SC and PB boards. The remaining voltages are monitored for abnormalities directly on the P board. -
Page 53: Voltage Distribution Of The Pa Board And Sos Detection
Voltage Distribution of the PA board and SOS Detection Figure 44 This diagram depicts the distribution of the PA board voltages to the DG, H, DT, DV, Z, and K boards. A high input at pin 111 of IC4005 will cause the unit to shut down and generate ten blinks of the power LED. - Page 54 Figure 45 The purpose of this pictorial of the component side of the PA board is to alert the technicians of the labeling and actual location of some the diodes mounted on the PA board.
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Page 55: Z Board (Sound) Sos Detection
Z Board (Sound) SOS Detection Figure 46 The 10V source of the Z board originates at the P board as 12Vdc. It is regulated to 10V by the PB board. It then passes through the PA and H boards before entering the Z board. -
Page 56: Th-42/50Px500U Self-Check Function (Reset)
TH-42/50PX500U Self-check Function (Reset) Diagnostic Procedures Self-check is used to automatically check the status of the ICs that are controlled via the IIC bus line. Under normal condition, the status is OK. A status indication other than OK indicates a problem within a specific board How to access the Self-check Screen (Reset) To get into the Self-check mode, press and hold down the VOLUME DOWN button on the front of the... - Page 57 Self-Check Screen Explanation Display Ref. Number. Description Board TU8200 TV Tuner DT-Board IC8211 Front Processor DT-Board IC8240 HDMSL PEAKS_Lite DT-Board H13UV2 IC2608 BBE Viva H-Board AVSWV IC2602 Video SW H-Board AVSWA IC2605 Audio SW H-Board IC4018 10 Bits A/D DG-Board GC3FS IC4019 GC3FS...
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Page 58: Th-42Pd50U
TH-42PD50U Power LED Flashing timing chart The unit is equipped with a self-protection circuit that places it in standby when there is an abnormality with one or more of the Power Supply circuits. The faulty circuit may be easily identified by counting the number of flashes emitted by the power LED located in front of the unit. -
Page 59: Th-42/50Pd50U Self-Check Function
TH-42/50PD50U Self-check Function Diagnostic Procedures Self-check is used to automatically check the status of the ICs that are controlled via the IIC bus line. Under normal condition, the status is OK. A status indication other than OK indicates a problem within a specific board How to access the Self-check Screen (Reset) To get into the Self-check mode, press and hold down the VOLUME DOWN button on the front of the unit, and the SLEEP button on the remote control. - Page 60 TH-42PD50U Display Ref. Number. Description Board TU3000 TV Tuner DT-Board IC8211 Front Processor DT-Board IC8240 HDMSL PEAKS_Lite DT-Board IC2608 BBE Viva H-Board AVSWV IC2602 Video SW H-Board AVSWA IC2605 Audio SW H-Board H34DG IC4026 GC4PRO DG-Board GC4P IC4018 10Bits A/D DG-Board HDMI IC5003...
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Page 61: Serviceman Mode
Serviceman Mode How to enter the Serviceman Mode While pressing the [VOLUME DOWN] button of the main unit, press the [RECALL] button of the remote control three times in a row (within 2 seconds). Adjustment method Use the remote control to navigate through the adjustment menu. [1] Button to select the Main items in forward direction Main Adjustment Items [2] Button to select the Main items in reverse direction... -
Page 62: Internal Pattern Generator
COPY RM-SET COPY STB-CAS Table 8 Internal Pattern Generator To access the internal pattern generator, select [OPTION] from the main adjustment item and press the [OK] button of the remote control for three seconds. Press the OK button to navigate through the different patterns. To Exit the internal pattern generator, press the [RETURN] button of the remote control Cable Diagnostic Screen To access the cable diagnostic screen: press, simultaneously, the [VOLUME UP]... -
Page 63: Adjustments
Adjustments Panel Label information Driver Set-up Item / Preparation Input an APL 100 % white signal. Set the picture controls to: Picture mode = Normal White Balance = Cool Aspect = 16:9 Figure 51 Adjustments To perform the following adjustments, please refer to the panel information label located on the heat sink of the panel. -
Page 64: Initialization Pulse Adjustment
Initialization Pulse Adjustment Item / Preparation Input a Crosshatch signal. Set the picture mode to Normal, and White Balance to Normal Adjustments Adjust the indicated test point for the specified waveform. Use test point TPSS1 of the SS board as the trigger source. Test point Volume Level... -
Page 65: P.c.b. (Printed Circuit Board) Exchange Procedure
P.C.B. (Printed Circuit Board) exchange procedure 1. Caution Wait 1 minute for the electrolytic capacitors to discharge before removing any PCB from the unit. 2. Quick adjustment after P.C.B. or Panel exchange TH-42PX500U P.C.B. Name Test Point Voltage Volume Remarks TPVSUS P Board Vsus... -
Page 66: Adjustment Volume Locations
Adjustment Volume Locations Figure 53... -
Page 67: Test Point Locations
Test Point Locations Figure 54... -
Page 68: Troubleshooting
Troubleshooting No Picture or Partial Picture NOTE: Please utilize this diagnostic flowchart after confirming that all input signals have the same problem. Is there a Is the picture in any panel portion of the screen? Is there 70V (VDA) at pins 1 and 2 of the connector SS12? - Page 69 Step 1 Step 2 Step 3 Is the SCAN CONTROL PULSE Check from the D Board to Is the waveform the SC Board OK? at TPSC1 ok? (Go to See Ref. *3 on board <Check Point> page 66. on page 66.) Check the DG or D board.
- Page 70 Step 1 Step 4 Is the Is the 15V at waveform at Check the TP_15V on the TPSS1 ok? P board. SS Board OK? See Ref. *4 on page 66. Check the Is the DG or D SUSTAIN CONTROL board. Check the PULSE from the D Board to the SS Board OK? (Go to...
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Page 71: Scan And Sustain Drive Waveform
Scan and Sustain Drive Waveform Figure 55 Scan and Sustain Drive Check points Figure 56... - Page 72 Step 5 <HD model>--- 42 / 37 inch Where is the picture problem? No (right half) Left half D Board Right half or left of the screen? (or C1 & C4 board) half of the screen Yes (left half) D Board (or C2 &...
- Page 73 Step 6 Is there no picture or a Vertical line wide vertical line Lower left PDP Panel at the lower of the screen left of the screen? No picture D Board (or C3 board) Is there no picture or a Lower right Vertical line wide vertical line...
- Page 74 Step 6 <HD model>--- 50 inch Where is the picture problem? No (right or middle) No (middle) D Board One third of the left, middle Left? Right? (or C2 & C5 or right of the screen board) D Board D Board (or C3 & (or C1 &...
- Page 75 Step 6 Is there Vertical line no picture or a wide Lower left PDP Panel vertical line at the of the screen lower left of the screen? No picture D Board (or C4 board) Is there no picture or a wide Vertical line Lower middle PDP Panel...
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Page 76: Vertical Line Problems
Vertical line problems Figure 57 Thin vertical line or no picture in one block A thin vertical line or picture in ¼ of the area driven by a C board indicates a defective driver IC that is mounted on the ribbon cable that connects the C board to the panel. To resolve this problem the panel has to be replaced. -
Page 77: Picture Ok, Sound Ng
Picture ok, Sound NG Is there Is there Check the no sound sound from H board. from all input the program sources? out jacks? Check the Z board and speakers. Is there Check the sound from No sound from H board. the AV analog TV reception terminal? -
Page 78: No Picture, No Sound
No picture, no sound Input Source check Is the picture and Check the No picture and no H board. sound of the sound from analog TV AV terminal reception Check the TA board. Check the No picture and sound H board. from the AV terminal No picture and sound Check the... -
Page 79: No Picture, Sound Ok
No picture, sound ok Check the Is there picture H board. from one of the AV inputs? Input Source check Is there a Check the No picture from analog picture from H and DG TV reception the AV board. terminal? Check the TA board. -
Page 80: How To Determine Whether The D Board Or Sc Board Is Defective
How to determine whether the D board or SC board is defective? Figure 58 Note: All SCAN CONTROL PULSES are located at pins 2, 3, 4, 6, 7, 8, 9, 13, 17, 18, 19, and 20 of connector SC20-D20. A missing waveform at one of the pins with the exception of pins 8, 9, and 13 will cause the power LED to blink. -
Page 81: Additional Troubleshooting Hints
Additional Troubleshooting Hints Symptom 1: Picture Noise - Many vertical lines are seen all over the screen. Cause: The voltage of the address period of the Scan Drive Signal at pin 8 of connector SC20/D20 has dropped. The problem is the D board. Figure 59 Symptom 2: Picture Noise - Part of the previous picture is visible on the screen. -
Page 82: Sc20 Or D20 Connector
Symptom 3: Picture Noise - Part of the previous picture remains on the screen. Cause: There is no Erase Pulse in the Scan Drive Signal at pin 13 of connector SC20/D20. The problem is the D board. Figure 60 The approach to find the defective board is to check the pins of the connector listed in the table below. -
Page 83: How To Determine Whether The D Board Or Ss Board Is Defective
How to determine whether the D board or SS board is defective? Figure 61 Note: All SUSTAIN CONTROL PULSES are located at pins 3, 4, 5, 6, 7, and 8 of one of the C (see the table above) and SS44 connectors. A missing waveform at one of the pins with the exception of pin 4 will cause the power LED to blink. -
Page 84: Defective Board
Symptom: Dark picture - Dark screen with a dim picture. Cause: There is no Sustain Control Pulse at pin 4 of the C or SS connector listed below. The voltage Ve of the initializing and address period of Sustain Drive Signal is missing. The problem is the D board. Figure 62 The approach to find the defective board is to check pin 4 of the connectors listed in the table below. -
Page 85: Glossary And Acronyms
Glossary and Acronyms ATSC (Advanced Television Systems Committee) Standardization body that developed the Digital Television Terrestrial formats. CDS (Current Directory Structure) DCF (Design rule for Camera File system) Unified standard established by Japan Electronics and Information Technology Industries Association (JEITA). DCM (Digital Carrier Module) A PCMCIA type card that is provided by the Cable operator FAT (Forward Application Transport)