Color television/video cassette recorder (64 pages)
Summary of Contents for Memorex MVT2090 A Series
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MVT2090 Series A SERVICE MANUAL COLOR TELEVISION/VIDEO CASSETTE RECORDER ORIGINAL MFR’S VERSION A Design and specifications are subject to change without notice.
SERVICING NOTICES ON CHECKING 1. KEEP THE NOTICES 6. AVOID AN X-RAY As for the places which need special attentions, Safety is secured against an X-ray by consider- they are indicated with the labels or seals on the ing about the cathode-ray tube and the high cabinet, chassis and parts.
CONTENTS SERVICING NOTICES ON CHECKING ..................A1-1 HOW TO ORDER PARTS ......................A1-1 CONTENTS ..........................A2-1 GENERAL SPECIFICATIONS ....................A3-1~A3-4 DISASSEMBLY INSTRUCTIONS 1. REMOVAL OF MECHANICAL PARTS AND P. C. BOARDS ..........B1-1, B1-2 2. REMOVAL OF DECK PARTS ..................... B2-1~B2-6 3.
GENERAL SPECIFICATIONS G - 1 CRT Size / Visual Size 9 inch / 222.8mmV System CRT Type Normal Deflection degree Magnetic Field BV/BH +0.45G / 0.18G Color System NTSC Speaker 1Speaker Position Side Size 3 Inch Impedance Sound Output 10%(Typical) G - 2 V C R System...
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GENERAL SPECIFICATIONS Timer Rec Set Channel Setup TV/CATV Auto ch Memory Add/Delete Guide ch Set TV Setup V-chip Set On/Off Timer Set Picture Audio Sap On/Off Auto Repeat On/Off On/Off Timer Set System Setup Clock Set Language Auto Clock On/Off Standard Time Daylight Saving Time Commercial Advance...
GENERAL SPECIFICATIONS CH Up CH Down Volume Up Volume Down Input Select Play F.Fwd Pause/Still Stop Rec/OTR Eject Counter Reset Speed Timer Rec TV Monitor Quick View Program Slow Auto Tracking Set/Tracking+ Set/ Tracking - Menu Enter Cancel Call TV/Caption/Text Sleep Timer Muting Zero Return...
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GENERAL SPECIFICATIONS Tent Card Important Safeguard Dew/AHC Caution Sheet AC Plug Adapter Quick Set-up Sheet Battery UM size x pcs UM4 x 2 pcs AC Cord AV Cord (2Pin-1Pin) Registration Card ESP Card 300 ohm to 75 ohm Antenna Adapter G - 1 5 Interface Switch...
DISASSEMBLY INSTRUCTIONS 1. REMOVAL OF MECHANICAL PARTS 1-3: TV/VCR BLOCK (Refer to Fig. 1-3) Remove the 2 screws 1. AND P.C. BOARDS Disconnect the following connectors: 1-1: BACK CABINET (Refer to Fig. 1-1) (CP353, CP401 and CP403). Remove the 4 screws 1. Unlock the support 2.
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DISASSEMBLY INSTRUCTIONS 1-5: DECK SHIELD PLATE (Refer to Fig. 1-5) 1-7: JACK PLATE AND SYSCON PCB (Refer to Fig. 1-7) Remove the 2 screws 1. Remove the screw 1. Remove the screw 2. Remove the Syscon PCB in the direction of arrow (A). Remove the 2 screws 2.
DISASSEMBLY INSTRUCTIONS 2. REMOVAL OF DECK PARTS NOTE In case of the Locker R installation, check if the two 2-1: TOP BRACKET (Refer to Fig. 2-1) positions of Fig.2-3-B are correctly locked. Extend the 2 supports 1. When you install the Cassette Side R, be sure to move Slide the 2 supports 2 and remove the Top Bracket.
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DISASSEMBLY INSTRUCTIONS 2-6: LOADING MOTOR/WORM (Refer to Fig. 2-6-A) Tension Arm Ass'y Remove the screw 1. Remove the Loading Motor. Remove the Worm. Fig. 2-7-A Loading Motor Worm Tension Connect Tension Band Main Chassis Tension Spring Tension Arm Ass'y Tension Holder •...
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DISASSEMBLY INSTRUCTIONS 2-8: T BRAKE ARM/T BRAKE BAND (Refer to Fig. 2-8-A) Remove the T Brake Spring. Idler Gear Turn the T Brake Arm clockwise and bend the hook Idler Arm Ass'y section to remove it. Unlock the 2 supports 1 and remove the T Brake S Reel Band.
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DISASSEMBLY INSTRUCTIONS 2-10: CASSETTE OPENER/PINCH ROLLER BLOCK/ P5 ARM ASS'Y (Refer to Fig. 2-10-A) Unlock the support 1 and remove the Cassette Opener. Remove the Pinch Roller Block and P5 Arm Ass'y. Cassette Opener Spring Position Fig. 2-11-B 2-12: FE HEAD (RECORDER ONLY) (Refer to Fig. 2-12) Pinch Roller Block Remove the screw 1.
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DISASSEMBLY INSTRUCTIONS 2-14: CAPSTAN DD UNIT (Refer to Fig. 2-14) 2-15: MAIN CAM/PINCH ROLLER CAM/JOINT GEAR (Refer to Fig. 2-15-A) Remove the Capstan Belt. Remove the 3 screws 1. Remove the E-Ring 1, then remove the Main Cam. Remove the E-Ring 2, then remove the Pinch Roller Remove the Capstan DD Unit.
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DISASSEMBLY INSTRUCTIONS NOTE 2-18: CASSETTE GUIDE POST/INCLINED BASE S/T UNIT/P4 CAP (Refer to Fig. 2-18-A) 1. When you install the Loading Arm S Unit, Loading Arm T Unit and Main Loading Gear, align each marker. Remove the P4 Cap. Unlock the support 1 and remove the Cassette Guide (Refer to Fig.
DISASSEMBLY INSTRUCTIONS 3. REMOVAL OF ANODE CAP 3. After one side is removed, pull in the opposite direction to remove the other. Read the following NOTED items before starting work. NOTE After turning the power off there might still be a potential Take care not to damage the Rubber Cap.
DISASSEMBLY INSTRUCTIONS 4. Insert one end of the Anode Support into the anode button, then the other as shown in Fig. 3-5. Support Fig. 3-5 Confirm that the Support is securely connected. Put on the Rubber Cap without moving any parts. 4.
DISASSEMBLY INSTRUCTIONS REMOVAL AND INSTALLATION OF When IC starts moving back and forth easily after desoldering completely, pickup the corner of the IC using FLAT PACKAGE IC a tweezers and remove the IC by moving with the IC desoldering machine. (Refer to Fig. 5-3.) REMOVAL NOTE Put the Masking Tape (cotton tape) around the Flat...
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DISASSEMBLY INSTRUCTIONS INSTALLATION When bridge-soldering between terminals and/or the soldering amount are not enough, resolder using a Thin- Take care of the polarity of new IC and then install the tip Soldering Iron. (Refer to Fig. 5-8.) new IC fitting on the printed circuit pattern. Then solder each lead on the diagonal positions of IC temporarily.
KEY TO ABBREVIATIONS Audio/Control H.SW Head Switch Automatic Color Control Hertz Audio Erase Integrated Circuit Automatic Frequency Control Intermediate Frequency Automatic Fine Tuning Indicator AFT DET Automatic Fine Tuning Detect Inverter Automatic Gain Control Killer Amplifier Left Antenna Light Emitting Diode A.PB Audio Playback LIMIT AMP...
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KEY TO ABBREVIATIONS SYNC Synchronization SYNC SEP Sync Separator, Separation Transistor TRAC Tracking TRICK PB Trick Playback Test Point UNREG Unregulated Volt Voltage Controlled Oscillator Video Intermediate Frequency Vertical Pulse, Voltage Display V.PB Video Playback Variable Resistor V.REC Video Recording Visual Search Fast Forward Visual Search Rewind Voltage Super Source...
SERVICE MODE LIST This unit provided with the following SERVICE MODES so you can repair, examine and adjust easily. To enter SERVICE MODE, unplug AC cord till lost actual clock time. Then press and hold Vol (-) button of main unit and remocon key simultaneously.
PREVENTIVE CHECKS AND SERVICE INTERVALS The following standard table depends on environmental conditions and usage. Parts replacing time does not mean the life span for individual parts. Also, long term storage or misuse may cause transformation and aging of rubber parts. The following list means standard hours, so the checking hours depends on the conditions.
PREVENTIVE CHECKS AND SERVICE INTERVALS CLEANING NOTE 2. TAPE RUNNING SYSTEM After cleaning the heads with isopropyl alcohol, do not When cleaning the tape transport system, use the run a tape until the heads dry completely. If the heads gauze moistened with isopropyl alcohol. are not completely dry and alcohol gets on the tape, 3.
WHEN REPLACING EEPROM (MEMORY) IC If a service repair is undertaken where it has been required to change the MEMORY IC, the following steps should be taken to ensure correct data settings while making reference to TABLE 1. NOTE: Initial Data setting will not be possible if clock has been set. To reset clock, either unplug AC cord and allow at least 30 minutes before Power On or alternatively, discharge backup capacitor.
PREPARATION FOR SERVICING How to use the Servicing Fixture Unplug the connector CP353, CP502, CP820 and CP850, then remove the VCR Block from the set. Connect as shown in the below figure using the Service Fixture. • Connect the Syscon PCB to the Main PCB with the cable JG162D and JG162E. •...
MECHANICAL ADJUSTMENTS 1. CONFIRMATION AND ADJUSTMENT 1-2: CONFIRMATION AND ADJUSTMENT OF TENSION POST POSITION Read the following NOTES before starting work. Set to the PLAY mode. • Place an object which weighs between 450g~500g on Adjust the adjusting section for the Tension Arm the Cassette Tape to keep it steady when you want to position so that the Tension Arm top is within the make the tape run without the Cassette Holder.
MECHANICAL ADJUSTMENTS 1-4: CONFIRMATION OF VSR TORQUE NOTE Install the Torque Gauge (JG002F) and Adapter (JG002B) If the torque is out of the range, replace the following on the S Reel. Set to the Picture Search (Rewind) mode. parts. (Refer to Fig.1-4-B) Check item Replacement Part Then, confirm that it indicates 120~180gf•cm.
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MECHANICAL ADJUSTMENTS 2-2: CONFIRMATION AND ADJUSTMENT OF AUDIO/ 2-3: TAPE RUNNING ADJUSTMENT CONTROL HEAD (X VALUE ADJUSTMENT) When the Tape Running Mechanism does not work well, Confirm and adjust the height of the Reel Disk. adjust the following items. (Refer to item 1-1) Confirm and adjust the position of the Tension Post.
MECHANICAL ADJUSTMENTS 3. MECHANISM ADJUSTMENT PARTS LOCATION GUIDE 1. Tension Connect P4 Post 2. Tension Arm T Brake Spring 3. Guide Roller T Reel 4. Audio/Control Head S Reel 5. X value adjustment driver hole Adjusting section for the Tension Arm position D2-4...
ELECTRICAL ADJUSTMENTS 1. BEFORE MAKING ELECTRICAL 2. BASIC ADJUSTMENTS ADJUSTMENTS (VCR SECTION) Read and perform these adjustments when repairing the 2-1: PG SHIFTER circuits or replacing electrical parts or PCB assemblies. Connect CH-1 on the oscilloscope to TP1002 and CH-2 CAUTION to TP4201.
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ELECTRICAL ADJUSTMENTS 2-3: VCO FREERUN 2-8: SUB BRIGHTNESS Place the set with Aging Test for more than 10 minutes. Receive the black pattern. (RF Input) Connect the digital voltmeter between the pin 7 and Using the remote control, set the brightness, contranst, pin 1 of CP602.
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ELECTRICAL ADJUSTMENTS 2-10: SUB COLOR 2-13: OSD HORIZONTAL Receive the color bar pattern. (RF Input) Activate the adjustment mode display of Fig. 1-1. Connect the oscilloscope to TP801. Press the VOL. UP/DOWN button on the remote control Using the remote control, set the brightness, contranst, until the difference of A and B becomes minimum.
ELECTRICAL ADJUSTMENTS 4-3: STATIC CONVERGENCE 4. PURITY AND CONVERGENCE ADJUSTMENTS NOTE Adjust after performing adjustments in section 4-2. NOTE Receive the crosshatch pattern from the color bar Turn the unit on and let it warm up for at least 30 generator.
TV POWER SCHEMATIC DIAGRAM +5V_REG IC IC501 KIA7805API DC JACK J503 (MAIN PCB) HEC0824-010010 RY503 ALKS325 D550 MTZJ5.6B D502 R549 CAUTION: DIGITAL TRANSISTOR 1SS133 DC POWER SW 220 1/4W Q501 KTC3198 PROTECTOR DC POWER SW. Q518 Q511 10.9 PROTECTOR DTC114ES KTC3198 Q503 PROTECTOR/...
INTERCONNECTION DIAGRAM TM101 OS4201 FROM TM101 OS4201 FRONT A/V JACK (MONO) J4204 J4205 HALL MAIN ROTOR SENSOR COIL MAGNET FG SENSOR V.OUT HEADPHONE JACK HEADPHONE JACK J351 J352 LOADING MOTOR M101 HALL HALL SWITCH LOGIC CP1002 CAP_FG CAP_VCO CAP/M/F/R I_LIMIT MOTOR_GND LD/CY_VCO CAP_CTL...
WAVEFORMS Y/C/AUDIO/CCD/HEAD AMP MICON POWER ON 11 PB 0.5V 20µs/div 1.0V 20µs/div 0.5V 0.5ms/div POWER ON POWER ON 13 PB 100mV 0.1µs/div 0.5V 10ms/div 1.0V 5ms/div TV POWER POWER ON 15 5.0V 20ms/div 1.0V 10µs/div 10mV 20us/div 16 500mV 5µs/div 1.0V 10ms/div 0.5V 1ms/div DEFLECTION...
WAVEFORMS 10.0V 5ms/div 50.0V 20µs/div IN/OUT 19 2.0V 20µs/div 0.5V 1ms/div 20 200mV 20µs/div 0.5V 20µs/div CHROMA/IF 21 50.0V 20µs/div 200mV 20µs/div SOUND AMP 22 50.0V 20µs/div 200mV 2ms/div NOTE: The following waveforms were measured at the point of the corresponding balloon number in the schematic diagram.
CHASSIS EXPLODED VIEW (TOP VIEW) M2003 UN4001 H5002 H5001 D1100 M101 NOTE: Applying positions AA, AB, AC and AD for the CLASS PART NO. MARK grease are displayed for this section. GREASE G-555G Check if the correct grease is applied for each position.
CHASSIS EXPLODED VIEW (BOTTOM VIEW) M2001 NOTE: Applying positions AA, AB, AC and AD for the CLASS PART NO. MARK grease are displayed for this section. GREASE G-555G Check if the correct grease is applied for each position. MG-33 FG-84M FL-721 I2-2...
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