MICRO COMPONENT SYSTEM MM-28 SERVICE Manual MICRO COMPONENT SYSTEM CONTENTS 1. Precautions 2. Specifications 3. Disassembly and Reassembly 4. Alignment and Adjustments 5. Special Circuit Descriptions 6. Troubleshooting 7. Exploded Views and Parts List 8. Electrical Parts List 9. Block Diagrams 10.
Examples: Handle brackets, Metal Part metal cabinets, screwheads and control shafts. The current measured should not Ohmmeter exceed 0.5 milliamp. Reverse the power- plug prongs in the AC outlet and repeat. Fig. 1-2 Insulation Resistance Test Samsung Electronics...
Make sure that the 8. Always connect a test instrument's ground portion around the serviced part has not lead to the instrument chassis ground been damaged. before connecting the positive lead; always remove the instrument's ground lead last. Samsung Electronics...
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SCAN : Manufactured for Scandinavian KATSO SATEESEEN! Market. VARNING: OSYNLIG LASERSTRÅLNING NAR DENNA DEL AR OPPNAD OCH SPARREN AR URKOPPLAD BETRAKTA EJSTRÅLEN! Fig. 1-4 Warning Labels (Location: Disc Clamper, Inner Side of Unit Door or Nearby Unit Chassis ) Samsung Electronics...
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6. After replacing the Pickup, reopen the Short Terminal. See diagrams below: THE UNIT (1) WRIST-STRAP CONDUCTIVE SHEET FOR GROUNDING short short short short terminal terminal terminal terminal SOH-A1 SOH94T4N SOH91CI(CAR,walkman) (CMS-V10,CMS-V30) SOH91VI(LDP) (CMS-V10,CMS-V30) Samsung Electronics...
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40 dB Total harmonic distortion 2.5% 20Hz ~ 20KHz(±1dB) Frequency response 90 dB(1kHz) Signal to noise ratio Compact Disc 75 dB(1kHz) Channel separation 0.1%(1kHz) Total harmonic distortion 1V (1kHz 0dB) Audio Output Specifications are subject to change without notice. Samsung Electronics...
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Remote Control TIMER TIMER/ ON/OFF CLOCK...
3. Disassembly and Reassembly 3-1 Cabinet-Top, Cabinet-Rear 1. Remove 6 screws of ! and 7 screws of @ of its rear part 2. Pull its top part upward vertically as shown in the figure 3-1 Figure 3-1 Samsung Electronics...
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Disassembly and Reassembly 3-2 Main PCB 1. Pull out the Main-PCB backward horizontally. Figure 3-2 Samsung Electronics...
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Disassembly and Reassembly 3-3 Cabinet-Bottom 1. Remove 3 screws ! and pull it out backward. Figure 3-3 3-4 CD-Pack 1. Undo 4 screws of ! and then remove the CD-Pack downward. Figure 3-4 Samsung Electronics...
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Remove the Gear (c) ) by pushing the hook. Lift the Gear(b) 1. 11. Remove the Gear(a) 2. 11. Remove 2 screws 3 and the then remove the Feed-Motor 4. 12. Remove the Chassis-Deck (M) 5. Figure 3-8 Samsung Electronics...
AM(MW) I.F Adjustment Output SSG FREQ. 450KHz AM Antenna SET FREQ. 522 KHz Adjustment AM SSG 450 KHz Speaker AM I.F COIL point Terminal (IFT1) Input Maximum output (Figure 4-3) Output VTVM Oscilloscope Figure 4-3 AM I.F Adjustment Samsung Electronics...
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Remark Connection See the Insert MTT-5512 Turn Bias oscillator diagram for Bias Figure 4-4 into Deck, then frequency coil(JT1) 85KHz ±5% adjustment press REC button to the right and left locations Oscilloscope VTVM Speaker Terminal (GND) Figure 4-6 Samsung Electronics...
Focus error bias can be adjusted from the range of +100mV ~ -100mV by connectiong the resistor with pin 63 (FEBIAS). 164K VB> VA> sev-stopb 160K FEBIAS sev-stop <5 Bit Counter> fcmpo FEBIAS fe-stopb Samsung Electronics...
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Extracting the DC part of RFI and RFO and comparing with the basic DC level, if RF Level is more than basic level, the FOK is output. The focus OK circuit generates a timing window of focus on to monitor the focus search status of focus serve. VC+0.625V Samsung Electronics...
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As the asymmertry due to variations in disc manufacturing can not be eilminated by thr AC coupling alone, the reference voltage of EFM comparator is controlled utilizing the fact that the generation probability of 1,0 50% each in the binary EFM signals. 100K 100K Samsung Electronics...
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Therefore, the output on processing monitor photo diode, must be a controlled current for getting regularly output power, thus the APC (Auto Power Control) circuit is composed. From Micom 150K 0.75K 43.5K 150K 300K 150K 5.15K LDON Samsung Electronics...
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If the control by MUTE signal from micom exist, and when input signal absent, two channel of right and left is builted in. CH2I CH2O GC2I GC2O GC1O GC1I GC1I CH1O MUTEI (From Micom) 5-1-11 Center Voltage Generation Circuit The Center Voltage is generated by using resistor dividing voltage. Samsung Electronics...
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After 10-track jumping, servo circuit gets out of the liner range and actuator,s tracking is unstable occasionally. Accordingly, unnecessary jumping with many tracking error should be prevented. 470K 680K 680K TDFCT DFCTI 66PF TRACKING 110K PHASE COMPENSATION 470K FSET Samsung Electronics...
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The characteristics of high frequency phase compensation in focus tracking servo and the characteristics of cut off frequecny in CLV low pass filter are test by FSET pin. SMON 220K 220K 100K SPDLO SMDP 220K 220K Double speed SPDL- SMEF FSET Samsung Electronics...
? RD5,RZD2,RR2,3,4, oscillate ? (pin no. 27 ;5.0V) Front PCB When the power is Replace µ-com ON 'H' displays at pin no. 47 ?(5V) Connect Front PCB and Main PCB. Check the connector Main PCB. Wafer JCW2,UCW1 Samsung Electronics...
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Check the B+ power pin no.9 source part in RD1,2,3,4, B+ circuits Confirm for TR short Q2 Base B+ ? replace it. Is Mute selected ? Remove it with Remocon Replace Headphone jack Headphone Jack short ? soldering condition Samsung Electronics...
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LC72131 pin no.20 Control ok? 1.7V 7.5V? Replace LC72131 AM VT Check the LC72131 LC72131 pin no.20 Control ok? 0.9V Check HIC1 pin 20? LPF(IL1,IL2) Check FEP interior output ok? Check TDA7430 function ok? pattern, and any line disconnections Samsung Electronics...
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2 R/P Deck : L Check for voltage at pin6 AMPS IC JIC2 AMPS When between songs : High (Normal) (LA2010) When playing song :Low (Normal) Osc Frequency : 85KHz Oscillate RECORD BIAS (85KHz) BIAS OSC When inoperative : JQ5, JQ6 check Samsung Electronics...
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Check Roulette Control Sensor Check oscillation of NXF100 Is Focus Search ok ? (16.9344MHZ) Does Laser function during Replace PICK UP Focus Search ? Check NIC9286 pin73 voltage Replace NIC9286 during Focus Search : 5V Replace NIC9223 or NIC9258 Samsung Electronics...
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Troubleshooting 6-3-2 Audio Output Malfunction Malfunction of Audio Output Check voltage of NIC05 : 5V Replace NIC05 Check waveform of NIC9223 Check NIC9223 soldering pin no. 12,13 Replace NIC9223 Check waveform of NC55R,L Check NIC9223 soldering Check Amp Samsung Electronics...
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CABINET W138.5 X H233.5 X D180 AH81-11047D WOOFER 5`` SG12G33AFA AH81-11047Z SCREW M4 X 10 BLACK AH81-11047H CORD ASS’Y Ø0.18 X 20 X 2P X 2.5m AH81-11047J CORD CLIP Ø11.7X Ø17 X 13t AH81-11047L FOOT Ø10 X 1.5t Samsung Electronics...
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FS1 to TM to BAL1 to PS1 to GA1 to Equalizer SPDL- BAL5 Spindle Servo LPF (Double Speed) SMDP SMON SMEF Comparator FSET MIRROR MIRROR DETECTION CIRCUIT Defect Dectection Built-in Post Filter Amp (L&R) Circuit FOK DETECTION CIRCUIT Samsung Electronics...
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PORT of GRID CONTROL FLT PORT of GRID CONTROL FLT PORT of GRID CONTROL FLT PORT of GRID CONTROL FLT POWER INPUT CONTROL PORT (5V) VdVp POWER INPUT GRID CONTROL PORT (-30V) PORT of SEGMENT CONTROL FLT PORT of SEGMENT CONTROL FLT Samsung Electronics...
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POWER INPUT PORT OF MAIN (5V) CRO2 CRO2 INPUT R/REC TAPE R/REC 3S/LED 3S SURROUND LED ACTIVE “H” POWER POWER ON/OFF ACTIVE “H” TA/MUTE TAPE MUTE ACTIVE “H” REC/MUTE REC MUTE ACTIVE “H” CRO2/OUT CRO2 OUTPUT ACTIVE “H” 9-10 Samsung Electronics...
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VSSA Analog VSS for servo part Micom clock input pin MDATA Micom data input pin Micom data latch input pin RESET Reset input pin MIRROR The mirror output for test The output pin of focus OK comparator Samsung Electronics 9-11...
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The input pin for AGC The output pin for AGC The input pin for EFM comparating CAGC The capacitor connection pin for AGC Feedback input pin of E I/V amplifier for EF Balance control GND for RF part 9-12 Samsung Electronics...
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Mute control input (“H”: Mute ON) Latch Signal input from Micom (Schmit Trigger) MDAT Latch Signal input from Micom (Schmit Trigger) Latch Signal input from Micom (Schmit Trigger) SRAM data I/O port8 (MSB) SRAM data I/O port7 Samsung Electronics 9-13...
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Spindle Motor drive (Velocity control in the PHASE mode) BCKI Audio data bit clock input of 48 bit/Slot (2.1168MHz) TESTV TEST input terminal (GND connection) DSPEED TEST input terminal (VDD connection) LRCHI Channel clock input of 48 bit/Slot (44.1KHz) 9-14 Samsung Electronics...
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Voltage Table KB9223 KA9258 KB9223 KB9223 KB9223 IC Name IC Name STOP MODE PLAY MODE STOP MODE STOP MODE PLAY MODE STOP MODE PLAY MODE STOP MODE PLAY MODE PLAY MODE 2.5V 4.5V 2.5V 4.5V 2.5V 2.5V 2.5V 2.5V 2.5V 2.5V 2.5V 4.5V...