LG GCE 8480B Service Manual

LG GCE 8480B Service Manual

Cd-rw drive
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This service manual provides a variety of service
information.
It contains the mechanical structure of the CD-
R/RW Drive and the electronic circuits in
schematic form. This CD-R/RW Drive was
manufactured and assembled under our strict
quality control standards and meets or exceeds
industry specifications and standards.
This CD-R/RW drive is an internal drive unit
designed for use with IBM PC, HP Vectra, or
1. General
1) Enhanced IDE interface.
2) Internal 5.25 inch, halfheight CD-R/RW Drive.
3) 2Mbytes buffer memory.
4) Audio CD like tray loading of a disc without using a caddy.
5) Power loading and power ejecting of a disc. The disc can also be ejected manually.
6) Supports Power saving mode and Sleep mode.
7) Vertical and Horizontal operation.
8) SuperLink Function.
2. Supported disc formats
1) Reads and writes data in each CD-ROM, CD-ROMXA, CD-I FMV, Video CD, and CD-EXTRA
2) Reads data in Photo CD (Single and Multi session).
3) Reads and writes standard CD-DA.
4) Reads and writes CD-R discs conforming to "Orange Book Part 2".
5) Reads and writes CD-RW discs conforming to "Orange Book Parts 3".
3. Supported write method
1) Disc at once (DAO), Session at once (SAO), Track at once (TAO), Variable packet, Fixed packet, and
Multi-session.
4. Performance
1) Random 100 ms average access time.
2) CD-R Record speed : 8X, 12X, 16X, 20X~40X (PCAV), 48X CAV.
3) CD-RW Record speed : 4X, 10X, 12X, 16X.
4) CD-ROM : Max 7,200 KB/s(Max 48x) Sustained Transfer rate.
5) Supports real time error correction and real time layered error correction at each speed.
6) PIO Mode 4, Multi DMA Mode 2, UDMA Mode 2.
7) Multimedia MPC-3 Spec compliant.
8) Support CD-TEXT read/write.
5. Audio
1) Output 16 bit digital data over ATA interface.
2) 8 Times Digital Filter for CD Audio
3) Software Volume Control
4) Equipped with audio line output and headphone jack for audio CD playback.
5) Front panel Volume Control for Headphone Output.
INTRODUCTION
compatible computer. It can write as much as 700
Mbytes of digital data into CD-R/RW disc, and can
read as much as 650 Mbytes of digital data stored
in a CD-ROM, CD-R and CD-RW disc.
This CD-R/RW Drive can easily meet the
upcoming MPC level 3 specification, and its
Enhanced Intelligent Device Electronics (E-IDE)
and ATAPI interface allows Plug and play
integration in the majority of today's PCs without
the need of an additional interface card.
FEATURES
3

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Summary of Contents for LG GCE 8480B

  • Page 1 INTRODUCTION compatible computer. It can write as much as 700 This service manual provides a variety of service Mbytes of digital data into CD-R/RW disc, and can information. read as much as 650 Mbytes of digital data stored It contains the mechanical structure of the CD- in a CD-ROM, CD-R and CD-RW disc.
  • Page 2: Location Of Customer Controls

    LOCATION OF CUSTOMER CONTROLS Front Panel Emergency Eject Hole Disc Tray Stop/Eject Button Volume Control Drive Activity Indicators Headphone Jack 1. Disc tray 5. Headphone jack This is the tray for the disc. Place the disc on the This jack is for connecting headphones or mini- ejected disc tray, then lightly push the tray (or speakers.
  • Page 3: Rear Panel

    Rear Panel IDE Interface Connector Analog Audio Output Connector Jumper Connector Power Connector Digital Audio Output Connector 1. Power Connector 3. Jumper Connector Connects to the power supply (5-and 12-V DC) of This jumper determines whether the drive is the host computer. configured as a master or slave.
  • Page 4: Cabinet And Circuit Board Disassembly

    DISASSEMBLY 1. CABINET and CIRCUIT BOARD 1-3. Cabinet and Main Circuit Board A. Remove the Cabinet in the direction of arrow (4). DISASSEMBLY (See Fig. 1-3) 1-1. Bottom Chassis B. Release 2 hooks (a) and remove the CD Tray A. Release 4 screws (A) and remove the Bottom Chassis drawing forward.
  • Page 5 2-2. Pick-up A. Release 2 screws (C) and remove the Pick-up. Pick-up Unit Pick-up Fig. 2-2...
  • Page 6 GLOSSARY ATIP Absolute Time In Pre-groove.With an additional modulation of the “Wobble”,the “Groove” contains a time code information Wobble The pre-groove in the Disc is not a perfect spiral but is wobbled with ; - a typical amplitude of 30ns - a spatial period of 54 -64µm (Pre-) groove The guidance track in which clocking and time code information is stored by means of an FM...
  • Page 7: The Differences Of Cd-R/Cd-Rw Discs And General Cd-Rom

    The differences of CD-R/CD-RW discs and General CD-ROM 1. Recording Layer Recordable CD has a wobbled pre-groove on the surface of disc for laser beam to follow track. Track pitch(p) a=30nm Read-only Disc CD-ROM (READ-ONLY DISC) Radial Direction Radial Error Signal 0.4~0.5 um Groove Land...
  • Page 8: Disc Materials

    3. Disc Materials 1) CD-ROM disc • It is composed of Silver _ colored aluminum plate and Reflective layer. • Groove (Pit) of aluminum plate make a track. • Laser wavelength : 780 nm, Laser Power (Read): 0.5mW • Signal is detected by the difference of reflective beam intensity between “pit”...
  • Page 9: Reading Process Of Optical Disc

    3) CD-RW Disc Label Printing Protective Layer Dielectric Layer(TL) Recording Layer Dielectric Layer(UL) Substrate (Polycarbonate) Groove Laser Beam • It is composed of polycarbonate layer, alloy(silver, arsenic) layer, aluminum reflectivity layer, protective layer. • An crystalized alloy layer is transformed into noncrystalized by the laser heat. Therefore, writing and reading is enabled by the difference of reflectivity.
  • Page 10: Writing Process Of Cd-R Disc

    5. Writing Process of CD-R Disc Incident (Write) Laser Power (Read) (Read) Laser Spot a b c d e f Position (Time) Laser Below "ORP"– Mark Too Short Spot Reflected At Optimum Record Power ("ORP") Light Signal Above "ORP" – Mark Too Long Recorded Mark Time...
  • Page 11 7. Organization of the PCA, PMA and Lead-in Area 1) Layout of CD-ROM disc Disc Center Diameter 120 mm Diameter 46 mm Diameter 15 mm Center hole Clamping and Label Area Information Area Read Only Disc Lead-in Area Program Area Lead-out Area 2) Layout of CD-R/RW disc Disc Center...
  • Page 12: Function Of Pca And Pma Area

    8. Function of PCA and PMA area 1) PCA (Power Calibration Area) • PCA area is used to determine the correct Laser Power for a disc. – Method 1 : PCA area is divided by a track. – Method 2 : The previous Calibration value is referred to. –...
  • Page 13: Writing Process Of Disc

    2) ROPC (Running Optimum Power Control) • Variable primary factor of Optimum Power – Change of Power sensitivity on the Disc. (limited to 0.05 *Po) – Wavelength shift of the laser diode due to the operating temperature change. – Change of the Spot aberration due to the Disc skew, Substrate thickness, Defocus.
  • Page 14: Super Link

    11. Recording capacity of CD-R/RW (74min Recording media) • (2048 Byte / Sector ) x ( 75 Sector / Second ) x ( 60 Second / Minute) x 74 Minute = 681,984,000 Bytes = 682 Mbytes • But the actual recording capacity is about 650 Mbytes. (according to the ISO 9660 standard, approximately 30 Mbytes are used to make directory structure and volume names.) 12.
  • Page 15 14. Full/Partial CAV & Zone CLV Recording Comparison Data transfer 48X CAV rate 40X CLV 40X PCLV Spindle Mode Change CLV Speed change Time Time 48x CAV 9540 9020 40x PCAV Time Time * Zone CLV * Full/Partial CAV Full/Partial CAV Zone CLV 1.
  • Page 16: Internal Structure Of The Pick-Up

    INTERNAL STRUCTURE OF THE PICK-UP 1. KRS-340B Circuit Diagram OP output terminal 2 Axis Actuator FCS + FCS - TRK + TRK - CXA2660N VLIM PDGND PDVC PDVCC FPDO FPDVCC FPDGND FPDVC LDVCC LDVCC VRDC VWDC1 VWDC2 LDGND LDGND VOUT PDIN VREF OSCEN...
  • Page 17: Signal Detection Of The P/U

    2. Signal detection of the P/U Infrared Iaser Pick-Up module Focusing Tracking Photo Diode 1) Focus Error Signal ==> (A+C)-(B+D) This signal is generated in RF IC (IC401 : MT1516) and controls the pick-up’s up and down to focus on Disc.
  • Page 18: Alpc (Automatic Laser Power Control) Circuit

    DESCRIPTION OF CIRCUIT 1. ALPC (Automatic Laser Power Control) Circuit 1-1. Block Diagram IC 401 ( MT1516 ) RLDON CN 201 RFPDSH IC 101 VRDCO S/H & VRDC VRDC VRDCG & Level Shift & Gain Optical Pick-up RDAC MT1518 KRS-340B FVREF Write FPDO...
  • Page 19: Focus Circuit

    2. Focus Circuit 2-1. Block Diagram HAVC -((E+F+G+H)) SBAD 0.8V MUTE2 IC401 MT1516 MUTE1 A,B,C,D HAVC E,F,G,H -{(A+C)-(B+D)} Disc Optical Motor unit Pick-up KRS-340B Focusing Compensator IC101 FCS- FCS+ MT1518 SBAD C562 R560 R149 FCIN FCS+ IC501 FCS- IC505 R566 C188 1.4V BD7907...
  • Page 20 3. Tracking & Sled Circuit 3-1-1. Block Diagram (Tracking Following) IC401 MUTE2 MT1516 MPPO MUTE1 (A+D)-(B+C) A,B,C,D HAVC E,F,G,H SPPO K*{(F+H)-(E+G)} Disc Optical Motor unit Pick-up KRS-340B Tracking Compensator TRK- TRK+ IC101 Sled Compensator MT1518 FMO2 SLED MOTOR Unit C561 R561 R148 TRKIN...
  • Page 21 3-1-2. Block Diagram (Seek) IC401 MUTE2 MT1516 MPPO MUTE1 (A+D)-(B+C) A,B,C,D HAVC E,F,G,H SPPO K*{(F+H)-(E+G)} Disc Optical Motor unit Pick-up (A+D)-(B+C) KRS-340B K*{(F+H)-(E+G)} DRCO TRK+ TRK- HAVC RFZC RFZC DRCO2 Vref HAVC MPPO SLED MOTOR Unit R456 C489 C142 TEZILP IC101 MT1518 R141...
  • Page 22: Tracking Servo

    3-2-1. Tracking Servo The aim of tracking servo is to make laser beam trace the data track on disc. Tracking Error(TE) Signal is generated from tracking error detected block in MT1516 using DPP(Differential Push-Pull) Method. DPP Method uses not only main beam(A, B, C, D) but also side beam(E, F, G, H) for correcting DC offset generated in Push-Pull Method.
  • Page 23 4. Spindle Circuit 4-1-1. Block Diagram (EFMCLV Servo) IC401 MUTE2 MT1516 MUTE1 RFSUM RFOUT EQRF -{(A+C)-(B+D)} Disc Optical Offset OSTCC Motor unit Pick-up Adj. KRS-340B C430 C410 IC101 1.4V PCK4M Data Data MT1518 RFIP Slicer RFIN C153 SPIN C141 CLV FD PCK4M R146 CLV PD...
  • Page 24 4-2-1. Block Diagram (FGCAV Servo) Optical Pick-up KRS-340B Disc Motor unit X101 33.8688MHz IC101 1.4V XTALO VCK4M Control Clock MT1518 XTALI Generator C153 PCK4M SPIN CAV FD CAV PD R146 VCK4M R543 Motor Kick 3.3V SPIN IC501 SPIN BD7907 1.4V CTL1 MUTE2 C507...
  • Page 25 4-3-1. Block Diagram (Wobble CLV Servo) C485 C486 C487 HAVC VHAVC AGC1C AGC2C AGC3C 81 82 AGC1 AGC2 Disc Motor unit Optical Pick-up ATFM KRS-340B AGC3 WBLSH WBLSH IC401 MT1516 VREF IC101 CLK33M Reference MT1518 Clock Gen. EFMCLK4 ATFG Tracking 1.4V Clock Gen.
  • Page 26: Troubleshooting Guide

    TROUBLESHOOTING GUIDE 1. Connect only the power cable Power check (Malfunction of LED and Tray). Check the Reset (Pin 170, 122 of Check the input of oscillation (pin Check the connection of 5V, 12V. IC101, pin2 of IC401). 109 of IC401). Check SCLK, SDATA, XLAT (pin 122, 123, 124 of IC401).
  • Page 27 Check the Reference voltage (+/- 10%). Check voltage of VREF(1.4V) Check VC (1.4V) of Drive IC (pin 53 of IC101, pin 27 of IC501). (pin27 of IC501). Check voltage of 2VREF(2.8V) (pin 52 of IC101). Check HAVC/PDVC(2.0V) Check FVREF/FPDVC (2.8V) Check FPDO(2.8V) (pin 34 of IC401, pin 13 of CN201).
  • Page 28 Check the initial operation (Power-on state) • Check the operating signal of Sled (pin 28, 29 of IC501 : SLIN1, 2). Sled move to inside. • Check the output signal of Sled (pin 34, 35, 36, 37 of IC501). Check the Spindle signal •...
  • Page 29 1. Waveform when Sled moves to inside When the sled moves to the inner position, SLIN1 the sine wave(refer to Fig1) inputs to /SLEDINSW SLIN1/SLIN2 (the input pins of drive IC). When Pick-Up unit approached to innermost position, the /SLEDINSW signal(CN402 pin 1) Zoom in becomes 0 V.
  • Page 30: Tray Motor

    Check Tray operation. Check /EJECT KEY (pin 11 of IC101). Check the control singal of Drive IC • Check the output signal of tray Check operating signal of tray (pin 22, 23 of IC501). (pin 49, 50 of IC501). (pin 26 of IC501). Check the power of DRIVE IC and •...
  • Page 31 2. Connection of Power and ATAPI cable CN101(ATAPI) Check identification of Drive. Pin no. Pin name Pin no. Pin name DASP Check the connection of ATAPI cable. PDIAG INTRQ IO16 Check the communication between DMACK PC and MT1518 (IC101). IORDY CSEL Check SDRAM.
  • Page 32 Check the identification of CD- ROM Disc (insert Disc). In case of Focus Up/Down • Check the drive signal of FCS-/+ • Check control signal of Drive IC (pin 1, 2 of CN201). Check the operation of Focus. (pin 22, 23 of IC501: CTL1,2). •...
  • Page 33 4. Operation of Focus Up/Down Waveform of Focus Search refer to Fig 5. In Focus Search, FE signal and SBAD signal are SBAD FCS+ used to Focus Servo On. Therefore, in case of Focusing Fail, check the FE signal and SBAD signal. Zoom in wave Fig.5...
  • Page 34 Check RF and Spindle Check EQRF input signal Check the signal of A~H (pin 39, 38, (Insert CD-ROM Disc). 37, 36, 30, 31, 32, 33, of IC401) (pin 45 of IC101) Check FG input (pin 20 of IC101). Check the control signal of Drive IC •...
  • Page 35 Check point of Writing Check the compatibility between Drive and Tool. Check whether or not additional Check Disc state (Fingerprint, Check whether or not Disc is writing is allowed. writeable (CD-R/CD-RW). Scratch, Dust...). (Given in the Disc Info of writing tool) Check Laser 1 (Check EEPROM) Activate ‘Addition Func.’...
  • Page 36 Check Laser 2 (No disc). Execute ‘D. Laser Inspection’ in Test Tool (GGOOM5). Check Reference voltage. OFF LEVEL. VRDC LEVEL FPD. Check Read Laser VWDC1 LEVEL FPD. VWDC2 FPD. Execute ‘E.ALPC Test for AS’ in Test Tool (GGOOM5) (select ‘VRDC Loop’, and ‘Trigger’). Check the input of ENBL (pin 33 of CN201 : ‘H’).
  • Page 37 Inspection of CD-R Recording Laser Inspection of CD-RW writing Laser Execute ‘E. ALPC Test for AS’ in Execute ‘E.ALPC Test for AS’ in Test Tool (GGOOM5) (Select Test Tool(GGOOM5) (Select ‘CD-RW Rec Mode’, and ‘CD-R Rec Mode’, and ‘Trigger’) ‘Trigger’) Chect input of ENBL (pin 33 of CN201 : ‘H’).
  • Page 38 Check Audio signal (Insert Audio Disc). Check SCLK, SDATA, XLAT Identify playback of Audio Disc (pin 122, 123, 124 of IC401). (Play Mode). Check Output signal of AUIO L/R Check Output signal of Check Output signal of AUDIO (pin 51, 54 of CN100). /AUD-MUTE (pin 103 of IC401).
  • Page 39 • How to use Test Tool (GGOOM5) A. Start 1. Install GCE-8480B -> PC Power ON -> Execute Windows. 2. Execute GGOOM5.exe on Windows (GGOOM5.exe & GGOOM5.cfg should be on the same Directory). 3. If you use GCE-8480B, “GGOOM5(Ver x.xx)” will be displayed on the Window Frame. 4.
  • Page 40 C. Laser Power Setup (VWDC / VWDC 1, 2 re-setup) 1. Remove disc on the tray. 2. Select ALPC/OPC on the menu bar, and then select Laser Power Setup menu. 3. Setup LD Power meter (Frequency :780nm, Measure Range : 0.01mW unit). 4.
  • Page 41 D. Laser Inspection (VRDC/VWDC1, 2 FPD & Level check) 1. Remove disc on the Tray. 2. Select ALPC/OPC on the menu bar and select Laser Inspection menu, then Laser Power Test window will appear. 3. Click Trigger button, then the result will be displayed with OK or NG separately. 4.
  • Page 42 E. ALPC Test for AS 1. Remove disc on the Tray. 2. Select ALPC/OPC on the menu bar and select ALPC Test for AS menu, then window will appear. 3. Select specific mode of ALPC Test mode and click Trigger button, then LD will be on. 4.
  • Page 43: Functional Block Diagram

    Functional Block Diagram...
  • Page 44: Major Ic Internal Block Diagram And Pin Description

    MAJOR IC INTERNAL BLOCK DIAGRAM AND PIN DESCRIPTION IC401 (MT1516) : CD-R/RW Analog Signal Processor Block Diagram AV S S 9 V R D C N AV D D 9 P / B Voltage AV S S 8 V R D C Detect R e f &...
  • Page 45 IC101(MT1518) : CD-R/RW Encoder/Decoder/Write Strategy / DSP /Interface /Micro Processor Block Diagram TEST Wobble EFMPLL Data Wobble Signal Reset Write Strategy Spindle (efmclk Slicer PRST# Interface Logic Logic Interface Control synthesizer) Logic Sync. FM Demodulator Data Demodulator Protection System & Bi-Phase data Subcode Clock Demodulator...
  • Page 46 • Pin Assignment Symbol Type Description Numbers RF Signals & S/H Control Pulses Analog Input Input of Main Beam Signal (A) Analog Input Input of Main Beam Signal (B) Analog Input Input of Main Beam Signal (C) Analog Input Input of Main Beam Signal (D) Analog Input Input of Side Beam Signal (E) Analog Input...
  • Page 47 Symbol Type Description Numbers (1). Output of Read RF (RRF) Signal RRF/WRF Analog Output (2). Output of Write RF (WRF) Signal WRFSUM Analog Input Input of Write RF (WRF) Summing Signal to ROPC Block ROPCO Analog Output Output of Amplified B-Level of Write RF Signal ROPCC Analog Input Vin(-) of Amplifier for Sampled B-Level of WRF Signal...
  • Page 48 Symbol Type Description Numbers MPXOUT1 Analog Output Multiplexer Output 1 for Signal Monitoring MPXOUT2 Analog Output Multiplexer Output 2 for Signal Monitoring Serial Interface & Other Digital Control Signals Digital Output ASP request signal output to MT1508 to send control signals via ASPREQ (TTL), 4 mA Driving serial interface.
  • Page 49 Digital I/O (TTL), 50K Pull-Up, (1). General I/O 1 for Mass Production Use (Initial Input Mode) GIO1 4 mA Driving (2). Output of Internal Digital Signal ( VWDC1 Symbol Type Description Numbers Digital I/O (TTL), (1). General I/O 2 for Mass Production Use (Initial Input Mode) GIO2 50K Pull-Up, (2).
  • Page 50 • Pin Description Pin Numbers Symbol Type Description Data PLL Interface (9) DPLLV DD Analog Power(3.3V) Power supply for data PLL and related analog circuitry. LPIOP Analog Output Data PLL VCO DAC positive output. LPION Analog Output Data PLL VCO DAC negative output. LPFOP Analog Output The positive output of loop filter amplifier.
  • Page 51 UP3_1 3.3V LVTTL I/O, Programmable bi-directional I/O. / UTXD Slew rate, Alternate function : TXD. Serial transmit data. 4mA driving, 75K pull-up UP3_0 3.3V LVTTL I/O, Programmable bi-directional I/O. / URXD Slew rate, Alternate function : RXD. Serial receive data. 4mA driving, 75K pull-up UALE...
  • Page 52 Analog Output Focus servo output. PDM output of focus servo compensator. Analog Output Tr acking servo output. PDM output of tracking servo compensator. PWMOUT Analog Output General purpose PWM output. Analog Output Disk motor control output. PWM output. Analog Output Feed motor control.
  • Page 53 Write Strategy Interface (5) 3.3V LVTTL output, Laser diode write power control output. (Write/Read mode SW Slew rate, signal) 2mA, 4mA, 6mA, 8mA, 10mA, 12mA, 14mA, 16mA PDR ODON 3.3V LVTTL output, Laser diode over drive control output. (Over drive control SW Slew rate, signal) 2mA, 4mA, 6mA,...
  • Page 54 WBLSH 3.3V LVTTL output, Sample pulse for wobble signal. 2mA, 4mA, 6mA, 8mA, 10mA, 12mA, 14mA, 16mA PDR Digital wobble signal (22.05 ± 1 K Hz) input ATFG 3.3V LV TTL Input, WBLCLK 3.3V LVTTL output, Wobble processing clock (432.18K Hz) output for MT1516. Slew rate, 4mA driving RFPDSH...
  • Page 55 WBLSH 3.3V LVTTL output, Sample pulse for wobble signal. 2mA, 4mA, 6mA, 8mA, 10mA, 12mA, 14mA, 16mA PDR Digital wobble signal (22.05 ± 1 K Hz) input ATFG 3.3V LV TTL Input, WBLCLK 3.3V LVTTL output, Wobble processing clock (432.18K Hz) output for MT1516. Slew rate, 4mA driving RFPDSH...
  • Page 56 3.3V LVTTL Output, SDRAM bank address 0 signal. For SDRAM application only. Slew rate, 2mA, 4mA, 6mA, 8mA, 10mA, 12mA, 14mA, 16mA PDR, 75K PPD ROE# 3.3V LVTTL Output, RAM Output Enable, low active. Slew rate, For SDRAM application, this pin is “Chip Select” signal output 2mA, 4mA, 6mA, connected to “CS#”...
  • Page 57 3.3V LVTTL Output, SDRAM clock enable signal output. For SDRAM application Slew rate, only. 2mA, 4mA, 6mA, 8mA, 10mA, 12mA, 14mA, 16mA PDR, 75K PPD 106,107,108, RD15 ~ RD0 3.3V LVTTL I/O, RAM Data bus. These pins are the bi-directional upper Buffer 109,110,112, Slew rate, RAM data bus to the external buffer memory.
  • Page 58 • Pin Description Terminal Symbol Description Terminal Symbol Description Hall amp.U positive input DVCC PWM block control power supply Hall amp.U negative input FCIN Focus driver input Hall amp.V positive input TKIN Tracking driver input Hall amp.V negative input BTL pre and Loading power supply Hall amp.W positive input LDO+ Loading driver positive output...
  • Page 59 IC501 (BD7907FS): Spindle Motor and 5ch Actuator Driver Block Diagram DVCC FCIN TKIN LDO+ LDO- TKO+ PGND1 TKO- FCO+ SPVM1 FCO- PGND2 AGND SLO1+ SPVM2 SLO1- SPRNF SLO2+ SLO2- CTL1 SLGND CTL2 SLRNF2 SPIN SLRNF1 DGND SLVDD LDIN SLIN2 SLIN1...
  • Page 60 EXPLODED VIEW PBM00 (MAIN C.B.A)

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