Samsung TT20A54X/XAX Service Manual

[Page 1] Samsung TT20A54X/XAX

Television Video Cassette Recorder Chassis : V15A Model: TT20A54X/XAX TT20A54X/RCL TT20A54X/GSU TT14A54X/XAX Television Video Cassette Recorder CONTENTS Precautions Specifications Alignment and Adjustment (VCR) Alignment and Adjustment (TV) Timing C...

[Page 2] Samsung TT20A54X/XAX

ELECTRONICS © Samsung Electronics Co., Ltd. APR.1999 Printed in Korea 3V15A-2001 ...

[Page 3] Samsung TT20A54X/XAX

1. Precautions 1-1 Safety Precautions 1. Be sure that all of the built-in protective devices are replaced. Restore any missing protective shields. 2. When reinstalling the chassis and its assemblies, be sure to restore all protective devices, inclu...

[Page 4] Samsung TT20A54X/XAX

1-1 Safety Precautions (Continued) 9. High voltage is maintained within specified limits by close-tolerance, safety-related components and adjustments. If the high voltage exceeds the specified limits, check each of the special components. 10. D...

[Page 5] Samsung TT20A54X/XAX

1-2 Servicing Precautions 1. Servicing precautions are printed on the cabinet. Follow them. 2. Always unplug the unitÕs AC power cord from the AC power source before attempting to: (a) Remove or reinstall any component or assembly, (b) Disconnec...

[Page 6] Samsung TT20A54X/XAX

1. Some semiconductor (Òsolid stateÓ) devices are easily damaged by static electricity. Such components are called Electrostatically Sensitive Devices (ESDs); examples include integrated circuits and some field-effect transistors. The following te...

[Page 7] Samsung TT20A54X/XAX

Samsung Electronics 2-1 Specifications 2. Specifications Format VHS Standard Recording System Rotary, azimuth two-head or four-head helical scanning system Luminance : FM azimuth recording Color signal : converted subcarrier phase shift recording Te...

[Page 8] Samsung TT20A54X/XAX

Alignments and Adjustments (VCR) Samsung Electronics 3-1 3-1 Mechanical Adjustments 3. Alignments and Adjustments (VCR) 3-1-1 Tape Transport Adjustment Note : The tape transport system was adjusted precisely in the factory, any adjustments is unnec...

[Page 9] Samsung TT20A54X/XAX

Alignments and Adjustments (VCR) 3-2 Samsung Electronics Fig. 3-3 3-2 Adjustments 3-2-1 Preadjustment 1. When parts are replaced, the tape ran sport system may be changed. When many different parts are replaced, refer to the procedures for the tape ...

[Page 10] Samsung TT20A54X/XAX

Alignments and Adjustments (VCR) Samsung Electronics 3-3 Fig. 3-7 Test Point Position (Main PCB : Parts) 3-2-2 (B) A/C HEAD TILT ADJUSTMENT 1. Playback a blank tape and observe the position of the tape at the lower flange of tape guide. 2. Confirm t...

[Page 11] Samsung TT20A54X/XAX

2.5 msec CH-2 PROBE H'D SW PULSE CH-1 PROBE CTL PULSE -Time/div. ; 5 msec Setting of Scope - Volt/div. ; CH-1 = 0.1V CH-2 = 0.2V 6.5 msec CH-2 PROBE H'D SW PULSE CH-1 PROBE CTL PULSE -Time/div. ; 5 msec Setting of Scope -...

[Page 12] Samsung TT20A54X/XAX

Alignments and Adjustments (VCR) Samsung Electronics 3-5 4. If Fig. 3-12 A does not meet the specification, adjust the S-guide roller up or down. 5. If Fig. 3-12 B does no meet the specification, adjust the T-guide roller up or down. 6. Slightly loo...

[Page 13] Samsung TT20A54X/XAX

Alignments and Adjustments (VCR) 3-6 Samsung Electronics 3-2-3 Check Switch over from RPS to Playback Mode 1. Check the transition from RPS to playback mode using a pre-recorded SP tape. Make sure that the leading edge of envelope comes to an ap...

[Page 14] Samsung TT20A54X/XAX

MODE TORQUE g/cm GAUGE PB NTSC 82.5 ± 27.5 Cassette Torquemeter PAL 79 ± 27 RPS 145 ± 30 Cassette Torquemeter Alignments and Adjustments (VCR) Samsung Electronics 3-7 3-3 Reel Torque Adjustments 1. The rotation of the capstan...

[Page 15] Samsung TT20A54X/XAX

Alignments and Adjustments (VCR) 3-8 Samsung Electronics 4. As rotating Disk S Reel Πclockwise and the region of adjusting in the Main Base (in shape of slit) clockwise or counterclockwise after inserting screw driver in the slit on Main Base. Ad...

[Page 16] Samsung TT20A54X/XAX

Alignments and Adjustments (VCR) Samsung Electronics 3-9 3-5-1 Adjust the switching point. 1. Play back the SP standard tape. 2. Connect the oscilloscope CH1 to EYM03 (HÕD) and CH2 to EYM11 (V.OUT) 3. Set the oscilloscope sync to CH1, and adjust VRM...

[Page 17] Samsung TT20A54X/XAX

Timing Chart Samsung Electronics 5-1 5. Timing Chart 5-1 Program S/W Timing Chart CAM POSITION SW A SW B SW C S/SEN E/SEN A a B b C c D d E e F f G STAND-BY PWR OFF LOAD START LOAD END REV PLAY STP1 STP2 F/R1 F/R2 OFF OFF ON ON START/END SENSOR : ON...

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Troubleshooting Samsung Electronics 6-1 6. Troubleshooting 6-1 No Power (No Raster, No Sound, Power Led Off) Normal Check the voltage of C814 (125V) Check the voltages of C804 (140~150V) Check D801, D802 D803, D804, F801, IC801 Abnormal Is IC801...

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6-2 No Picture or Raster Troubleshooting 6-2 Samsung Electronics Normal Abnormal Normal Normal Abnormal Normal Abnormal Normal Check the voltage of IC202, IC201, TU01,VDD Check the main power Abnormal Check the voltage of IC201 pin 5 (Normal : 5V)...

[Page 20] Samsung TT20A54X/XAX

6-3 No Sound (Picture OK) Troubleshooting Samsung Electronics 6-3 Normal Abnormal Normal Normal Normal Abnormal Normal Abnormal Abnormal Abnormal Abnormal Abnormal Abnormal Abnormal Normal Abnormal Check the voltage of IC201 Pin 48 (9V) Check/Repla...

[Page 21] Samsung TT20A54X/XAX

Troubleshooting 6-4 Samsung Electronics 6-4 No Vert Scan Normal Abnormal Abnormal Abnormal Abnormal Normal Normal Check R409 Replace R409 Check IC301 Check the waveform of IC201 Pin 24 Check vertical output terminal circuit Replace IC301 Check IC2...

[Page 22] Samsung TT20A54X/XAX

Troubleshooting Samsung Electronics 6-5 6-6 No Audio During Playback Normal Abnormal Abnormal Normal Normal Check the audio signal of ICM301 Pin 96 Check the line of RM514, CM515 LM503, RM501, RM502 (A. out Line) Check if ICM301 Pin 16, 17 is Lo...

[Page 23] Samsung TT20A54X/XAX

Troubleshooting 6-6 Samsung Electronics 6-7 No Audio During Record Abnormal Normal Press the "REC" button for the recording mode Check the audio signal of ICM301 Pin 7 Check the audio signal of ICM301 Pin 98 Normal Check the bias signa...

[Page 24] Samsung TT20A54X/XAX

Troubleshooting Samsung Electronics 6-7 6-8 No Playback Normal NO Normal OK Normal Insert a video tape and start PLAYBACK Check the tape loading Check ICM601 Pin 13,14 (Start/end sensor) Check the tape Check the Rotation of Cylinder Check ICM601 ...

[Page 25] Samsung TT20A54X/XAX

Troubleshooting 6-8 Samsung Electronics 6-9 REC Doesn’t Operate Abnormal Normal Normal Check the PLAYBACK operation Insert a tape and set to the REW mode Check if the voltage of ICM601 Pin 78 is high (D REC) Check ICM601 Check the tape takeout ...

[Page 26] Samsung TT20A54X/XAX

Troubleshooting Samsung Electronics 6-9 6-11 “REW” Doesn’t Operate Normal REW Check the REW operation  Check ICM601 Pin 4, 5, 6 (PROG. SW) Refer to "Deck doesn't Operated during playback" Check the Deck. Refer to "REW N...

[Page 27] Samsung TT20A54X/XAX

Troubleshooting 6-10 Samsung Electronics 6-13 “ Reverse Direction Search Screen “ Doesn’t Operate Normal Searching Speed Set to the reverse direction search screen mode Check the speed of capstan motor Replace ICM601 Playback Speed Check...

[Page 28] Samsung TT20A54X/XAX

Troubleshooting Samsung Electronics 6-11 6-14 Tape Doesn’t Load Normal Normal Insert a tape Check the followings: ICM601 Pin 17 : HIGH ICM601 Pin 18 : LOW  Check the voltage of ICM603 (PC 9V) Check the B + terminal of loading motor Check/Rep...

[Page 29] Samsung TT20A54X/XAX

Troubleshooting 6-12 Samsung Electronics 6-15 Capstan Doesn’t Rotate Normal Normal Check CNM201 Pin 4 (2.5V)  Check the voltage of CNM201 Pin 8 (5V) Check the AL (5V) Check the capstan motor Abnormal Abnormal Insert a tape and set to the PLAY...

[Page 30] Samsung TT20A54X/XAX

Troubleshooting Samsung Electronics 6-13 6-16 Cylinder Doesn’t Rotate (Slow) Normal Check the rotation speed of cylinder  Check XTM601 (10Mhz) Replace XTM601 Check the cylinder motor Abnormal (Fast) Insert a tape and set to the PLAYBCAK mode ...

[Page 31] Samsung TT20A54X/XAX

Troubleshooting 6-14 Samsung Electronics 6-17 No Picture During Playback Normal Check the FM video signal at ICM301 Pin 74  Check the ENV connecting pattern Abnormal Insert a tape and set to the PLAYBCAK mode Check IC201 neighbor circuits Normal...

[Page 32] Samsung TT20A54X/XAX

Troubleshooting Samsung Electronics 6-15 6-18 No Picture During Record Insert a Video tape and Set to the REC mode Normal Check the ICM301 Pin 42 has the Video input signal Check the Input/Output block (IC201) Abnormal Check the ICM301 Pin 66 has ...

[Page 33] Samsung TT20A54X/XAX

Troubleshooting 6-16 Samsung Electronics 6-19 No Color During Playback    No Color (On Playback) Check the ICM301 Pin 72 has the color signal Check Pin 14 (Rotary) Check ICM301-62 OSC : 3.57MHz 30Hz Replace ICM301 XTM301 Replace Check ...

[Page 34] Samsung TT20A54X/XAX

Troubleshooting Samsung Electronics 6-17 6-20 No Color During Record Abnormal    Normal No Color (On REC) Check the ICM301 Pin 72 has the color signal Check ICM301- 62 OSC (3.5795MHz 30Hz) Replace XTM301 Check the color signal of ICM3...

[Page 35] Samsung TT20A54X/XAX

7. Exploded View & Parts List 7-1 TT14A54X Exploded View & Parts List Samsung Electronics 7-1 No Code No. Description;Specification Q’ty Remark 1 AA92-00002M ASSY-CABINET,FRONT;TT14A5,MEX,V15A,14 1 1-1 AA64-70009D BADGE-BRAND;-,AL,-,L40,GOL...

[Page 36] Samsung TT20A54X/XAX

Exploded View & Parts List 7-2 Samsung Electronics 7-2 TT20A54X No Code No. Description;Specification Q’ty Remark 1 AA92-00002L ASSY-CABINET,FRONT;TT20A5,MEX,V15A,19 1 1-1 AA64-70010D BADGE-BRAND;-,AL,-,L50,GOLD,R2 1 1-2 3001-001037 SPEAKER;5W,...

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Exploded View & Parts List Samsung Electronics 7-3 7-3 Mechanical Parts (Top Side) Loc. No Parts No. Description ; Specification Remark G001 K250 K248 K110 K502 K350 K330 K182 K140 K490 K530 K240 G532 G420 G450 K546 G510 B410 B440 B444 B446 B44...

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Exploded View & Parts List 7-4 Samsung Electronics 7-4 Mechanical Parts (Bottom Side) G542 B560 B484 B458 B500 B488 B462 (OPTIONAL) S.N.A. N.A. S.N.A. S.N.A. B456 K222 K200 K225 K221 B570 B238 S.N.A. : Service Not Available Loc. No Parts No. ...

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Electric Parts List Samsung Electronics 8-1 Loc. No. Code No. Description ; Specification Remark Loc. No. Code No. Description ; Specification Remark ASSY-PCB,MAI...

[Page 40] Samsung TT20A54X/XAX

Electric Parts List 8-2 Samsung Electronics ASSY-PCB,MAIN(OPT) * AA94-10149WASSY-PCB,MAIN(OPT);V15A,19,S/V,MEXICO C101 2202-000127 C-CERAMIC,MLC-AXIAL;10NF,+80-2 C102 2401-000660 C-ELECTROLYTIC;CE04WTAPG50V2.2 C104 2202-000127 C-CERAMIC,MLC-AXIAL;10N...

[Page 41] Samsung TT20A54X/XAX

C801 2306-000318 C-FILM,MPPF;220NF,20%,250V,-,2 C803 2201-000987 C-CERAMIC,AC;CK45PE400V222-M(T C804 2401-003024 C-AL;220UF,20%,200V,WT,TP,22X35.1MM C805 2303-000163 C-FILM,PPF;2.2NF,5%,800V,-,-,T C806 2301-000310 C-FILM,PEF;68NF,5%,50V,8.0X8.5 C807 ...

[Page 42] Samsung TT20A54X/XAX

R103 2001-000429 R-CARBON;1Kohm,5%,1/8W,AA,TP,1.8x3.2mm R104 2003-001037 R-METAL(OXIDE);39OHM,5%,2W,AF, R152 2001-000221 R-CARBON;1.2KOHM,5%,1/8W,AA,TP R153 2001-000734 R-CARBON;4.7KOHM,5%,1/8W,AA,TP R154 2001-000780 R-CARBON;470ohm,5%,1/8W,AA,TP,1.8...

[Page 43] Samsung TT20A54X/XAX

R932A 2001-000290 R-CARBON;10KOHM,5%,1/8W,AA,TP, R933 2001-000281 R-CARBON;100OHM,5%,1/8W,AA,TP, R934 2001-000449 R-CARBON;2.2KOHM,5%,1/8W,AA,TP R935 2001-000472 R-CARBON;2.7KOHM,5%,1/8W,AA,TP R936 2001-000290 R-CARBON;10KOHM,5%,1/8W,AA,TP, RH01 2002...

[Page 44] Samsung TT20A54X/XAX

CM501 2202-002037 C-CERAMIC,MLC-AXIAL;100NF,+80-20 CM502 2401-002462 C-ELECTROLYTIC;CE04WTAPG16V33M CM503 2401-000914 C-AL;22UF,20%,16V,GP,5X11,5,TP CM504 2401-001537 C-AL;47UF,20%,25V,GP,6.3X7MM,5 CM505 2202-002037 C-CERAMIC,MLC-AXIAL;100NF,+80-20 C...

[Page 45] Samsung TT20A54X/XAX

RM307 2001-000290 R-CARBON;10KOHM,5%,1/8W,AA,TP, RM308 2001-001114 R-CARBON(S);270OHM,5%,1/2W,AA, RM309 2001-000969 R-CARBON;75OHM,5%,1/8W,AA,TP,1 RM310 2001-000786 R-CARBON;47KOHM,5%,1/8W,AA,TP, RM311 2001-000977 R-CARBON;8.2Kohm,5%,1/8W,AA,TP,1.8x3...

[Page 46] Samsung TT20A54X/XAX

ASSY-PCB,A/V * LA95-40005SASSY-PCB,A/V;-,KCV13A,V15A,13,19 05VER AA41-10290F PCB-A/V;KH1,1L,FR-1,227x50.5x1.6T,-,- CV602 3711-002645 POST-HEADER;67094-006(AUTO) CV602 AA39-20027ALEAD-CONNECTOR,ASSY;-,67096-006,S,6P,300 JA01 3722-000171 JACK-RCA;1P,3....

[Page 47] Samsung TT20A54X/XAX

9. Block Diagram Block Diagram Samsung Electronics 9-1 33V TUNER EXT AUDIO SPEAKER CRT MICOM E 2 PROM M/DECK EXT VIDIO S/W IC SPS CONTROL I-CHIP SWITCHING TRANS SOUND AMP IC601 CRT-DRIVE Q401 H-OUT VERTICAL KA2131 5V 6V RF VIDEO AUDIO RF AUDIO 9V RF...

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11. PCB Layout 11-1 TV Main PCB Layout Samsung Electronics 11-1 D101 172 151 D102 62 230 D201 84 195 D202 123 143 D203 123 140 D204 123 138 D205 99 148 D206 90 140 D207 90 137 D208 93 131 D301 74 101 D401 99 116 D402 100 113 D403 61 74 D404 79 61 D4...

[Page 49] Samsung TT20A54X/XAX

PCB Layout 11-2 Samsung Electronics 11-2 Video Main DM101 252 201 DM102 278 209 DM103 263 11 DM104 208 201 DM105 278 232 DM106 221 229 DM301 249 142 DM302 243 166 DM607 55 41 DM608 55 43 DM609 59 36 DM610 50 98 DM611 122 78 DM612 106 16 DM613 106 10...

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PCB Layout Samsung Electronics 11-3 11-3 Main CONTROL ...

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10. Wiring Diagram Wiring Diagram Samsung Electronics 10-1 ...

[Page 52] Samsung TT20A54X/XAX

TP2 TP1 TP4 TP3 Schematic Diagrams 12-1Samsung Electronics 12. Schematic Diagrams 12-1 VCR (AV-BLOCK) Y Signal REC Y Signal PB Audio PB C Signal REC C Signal PB REC Audio TP1 TP2 TP3 TP4 ...

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Schematic Diagrams 12-2 Samsung Electronics 12-2 VCR (SYSTEM BLOCK) TP5 TP9 TP10 TP6 TP7 TP8 TP5 TP6 TP7 TP8 TP9 TP10 ...

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Schematic Diagrams 12-3Samsung Electronics 12-3 VCR (POWER BLOCK) ...

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Schematic Diagrams 12-4 Samsung Electronics 12-4 TV (MAIN BLOCK) TP17 TP18 TP19 TP11 TP12 TP13 TP15 TP16 TP14 TP27 TP28 TP29 TP30 TP32 TP31 TP35 TP25 TP26 TP24 TP23 TP21 TP22 TP20 TP36 : Power Line : Signal Line ...

[Page 56] Samsung TT20A54X/XAX

Schematic Diagrams 12-5Samsung Electronics TP11 TP12 TP13 TP14 TP15 TP16 TP17 TP18 TP19 TP20 TP21 TP22 TP23 TP24 TP25 TP26 TP27 TP28 TP29 TP35 TP36TP30 TP31 TP32 TP33 TP34 12-4-1 Waveform ...