SAFETY PRECAUTIONS Operating the receiver outside of its cabinet or with its The picture tube used in this receiver employs integral back removed involves a shock hazard. Work on implosion protection. Replace with a tube of the same these models should only be performed by those who type number for continued safety.
SPECIFIC SERVICE INSTRUCTIONS DISASSEMBLY INSTRUCTIONS 1-3: TV/VCR BLOCK (Refer to Fig. 1-3) 1. REMOVAL OF MECHANICAL PARTS Remove the 2 screws 1. AND P.C. BOARDS Disconnect the following connectors: 1-1: BACK CABINET (Refer to Fig. 1-1) (CP401, CP502, CP4201 and CP4202). Remove the 6 screws 1.
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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.
NOTE 2. REMOVAL OF DECK PARTS When you install the Tape Guide L, install as shown in the 2-1: TOP BRACKET (Refer to Fig. 2-1) circle of Fig. 2-3-B. (Refer to Fig. 2-3-B) Remove the 2 screws 1. Slide the 2 supports 2 and remove the Top Bracket. NOTE Tape Guide L When you install the Top Bracket, install the screw (1)
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2-6: LINK ASS'Y (Refer to Fig. 2-6) 2-9: TENSION ASS'Y (Refer to Fig. 2-9-A) Set the Link Ass'y to the Eject position. Move the Inclined S Ass'y to the back side. Remove the (A) side of the Link Ass'y first, then remove Remove the Tension Spring.
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2-11: S REEL/T REEL (Refer to Fig. 2-11) NOTE Remove the S Reel and T Reel. Do not touch the Pinch Roller. (Use gloves.) Remove the 2 Polyslider Washers 1. When you install the Pinch Roller Block, install as shown in the circle of Fig.
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2-15: AHC ASS'Y/CYLINDER UNIT ASS'Y (Refer to Fig. 2-15) Middle Gear Unlock the support 1 and remove the AHC Ass'y. E-Ring Remove the 3 screws 2. Remove the Cylinder Unit Ass'y. Main Cam NOTE Pinch Roller Cam When you install the Cylinder Unit Ass'y, tighten the screws from (1) to (3) in order while pulling the Ass'y Joint Gear toward the left front direction.
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2-19: LOADING GEAR S/T ASS'Y (Refer to Fig. 2-19-A) 2. When you install the Clutch Actuator, install as shown in the circle of Fig. 2-19-C. (Refer to Fig. 2-19-C) Remove the E-Ring 1 and remove the Main Loading Gear. Remove the Capstan Brake Spring. Slide the Main Rod and remove the Capstan Brake Ass'y.
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.
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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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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 V-SYNC...
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. Unless maintenance is properly carried out, the following service intervals may be quite shortened as harmful effects may be had on other parts. Also, long term storage or misuse may cause transformation and aging of rubber parts. Time 1,000 1,500...
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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.
NOTE FOR THE REPLACING OF 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.
PREPARATION FOR SERVICING Basic Servicing Position (In case of needing to check on all blocks) Unplug the connector CP502, CP4201 and CP4202, then remove the TV/VCR Block from the set. Unplug the connector CP810, CP820 and CP805, then remove the Main PCB from the VCR Block. Connect as shown in the below figure using the Service Fixture.
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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 Tension Adjust until the edge of the Tension the Cassette Tape to keep it steady when you want to Arm is positioning within 0.5mm range from the make the tape run without the Cassette Holder.
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1-4: CONFIRMATION OF VSR TORQUE 2. CONFIRMATION AND ADJUSTMENT OF TAPE RUNNING MECHANISM Operate within 4~5 seconds after the reel disk begins to turn. Tape Running Mechanism is adjusted precisely at the Install the Torque Gauge on the S Reel. Set to the Rewind factory.
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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.
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3. MECHANISM ADJUSTMENT PARTS LOCATION GUIDE 1. Tension Adjust X value adjustment driver hole 2. Tension Arm P4 Post 3. Guide Roller T Brake Spring 4. P1 Post T Reel 5. Audio/Control Head S Reel...
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1. ADJUSTMENT PROCEDURE 2. BASIC ADJUSTMENTS Read and perform these adjustments when repairing the (VCR SECTION) circuits or replacing electrical parts or PCB assemblies. 2-1: PG SHIFTER CAUTION Connect CH-1 on the oscilloscope to TP1002 and CH-2 • Use an isolation transformer when performing any to TP4201.
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2-3: RF AGC 2-8: WHITE BALANCE NOTE: Adjust after performing CUT OFF adjustment. Receive the VHF HIGH (70dB). Connect the digital voltmeter between the pin 5 of Place the set with Aging Test for more than 15 minutes. CP602 and the pin 1 (GND) of CP602. Receive the color bar pattern.
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2-13: VERTICAL SHIFT NOTE: Adjust after performing adjustments in section 2-12. Receive the center cross signal from the Pattern Generator. Using the remote control, set the brightness and contrast to normal position. Activate the adjustment mode display of Fig. 1-1 and press the channel button (07) on the remote control to select "V SHIFT".
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4. PURITY AND CONVERGENCE 4-3: STATIC 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. minutes before performing the following adjustments. Combine red and blue of the 3 color crosshatch pattern Place the CRT surface facing east or west to reduce the on the center of the screen by adjusting the pair of 4...
GUIDE FOR REPAIRING IC DESCRIPTION SYSCON PCB OEC7043C (IC1001) PIN NO. PIN NAME DESCRIPTION MSSEN A I Input terminal of mecha state sensor. MSSEN B I Tape end sensor input signal. I Tape start sensor input signal. HI-FI ENV I Input terminal of Hi-Fi RF envelope. VIDEO ENV I Input terminal of video RF envelope.
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SYSCON PCB OEC7043C (IC1001) PIN NO. PIN NAME DESCRIPTION OSD VCC - 5V - Filter connection for HLF. VHOLD - Condenser connection for VHOLD. CVIN I Composite Video input terminal. - Ground. H SYNC I Input terminal for H-SYNC. V SYNC I Input terminal for V-SYNC.
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MECHANISM TIMING CHART SLOW : SETTING SPEED TO SERVO : CAPSTAN FWD ROTATING LOADING DIRECTION DIRECTION : MECHANICAL MOVEMENT AND CAPSTAN ROTATING (FWD) : CAPSTAN RVS ROTATING : MECHANICAL MOVEMENT (NO CAPSTAN ROTATING) DIRECTION EJECTION UNLOADING STP3 R. SLOW F. SLOW PB/STP STP2 FF/REW...
TROUBLESHOOTING GUIDE (Television division) It dose not enter the power suppiy(1) When it pushed the Investigate unreg8V line and power button is it AT5V line. lighted? The 7th pin of cp810 Investigate D508. does it exist DC13V? Does the base voltage of Investigate the 28 pin of IC1001 Q502 and Q513 normal? Q512,Q513 make on/off?
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No sound. The voltage of CD355 Investigate speaker and and CD356 do change headphonejack. with the volume key? Investigate D505 and D534 The 1st pin of IC352 and the peripheral circuit. does it exist DC7.1V? The 2nd pin of IC352 Investigate IC352 and the does it exist DC3.5V? peripheral circuit.
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A color doesn't adhere to it Are the adjustment of Color is adjust. the color standard? Is it receive the sgnal of Receive signal of the color. the color? Is the waveform of the 36th Investigate the X602 and the pin of IC601 normal? peripheral circuit.
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An only horizontal line appears Is the waveform of the Investigate the IC601 and the 1st pin of IC401 normal? peripheral circuit. Investigate D411,R452 and a The 6th pin of IC401 peripheral circuit. does it exist DC25V? Investigate IC401,CP401 and the peripheral circuit.
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(Video division) Release playback Insert a cassette, push a PLAY button. Investigate a tape roading, Is the playback released roading belt, mode sensor, DD approximately 3 seconds motor, and cylinder motor. later? Is the playback released Investigate a reel sensor and approximately 6 seconds reel belt.
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When playback, a screen doesn't appear Whether it takes 5V for Investigate a power supply Whether does a screen IC4001 25, 54, 56, circuit. of E-E appear or not? 75, 87th pin or not? Whether there are PB Investigate a connection of Y/C signal for TP4001 IC4001 and cylinder.
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Noise (it is really back to have cleaned a head) for a picture when playback Whether does Exchange cylinder unit and TP4001 FM signal CP4001. appear or not? There is FM signal for Investigate a peripheral IC4001 88th ,89th circuit of IC4001. pin? There is FM signal for Investigate a peripheral...
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When playback, a sound doesn't appear Whether does a It refers to a clause of " E-E sound appear doesn't appear". with E-E or not? Investigates wound, whether a connector with an audio head is complete and inserted into Whether there is an CP4005 to investigate whether audio signal for IC4001 there isn't becoming dirty or not...
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Capstan DD motor doesn't rotate When playback, is the Investigate a power supply voltage of CP1004 circuit. 5th, 8th pin 5V? When playback, whether is voltage of IC1001 12th pin Exchange IC1001. 5V or not? When playback, whether is Investigate IC1001 76th,65th pin voltage of IC1001 4th pin and the peripheral circuit.
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A audio can't record it A bias level with L4003 Investigate Q4005 and is OK (approximately Q4006 peripheral circuit. 40Vp-p) Whether there is an Investigate IC5501 and the audio signal for peripheral circuit. IC4001 80th pin or not? Whether there is an Investigate IC4001 and the audio signal for IC4001 peripheral circuit.
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Though a cassette can insert it, a tape doesn't move Investigate a portion related to Does mode indicator roading motor and a mode appear in Display? sensor. Does VCR operate with Investigate IC1001 and CP1005. the remote control? Investigate a tact SW. Recording mechanism works, but no video recorded from input jack or tuner...
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No E-E (no video and audio from tuner) Whether TU601 7th pin Investigate a power supply is 5V or not, whether is circuit. 9th pin 30V or not? Whether is a video signal and audio signal Exchange IC601 and investigate IC601 53 and 57th pin the peripheral circuit.
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A sound shakes Whether is an audio Exchange an audio head. head wounded or not? Whether is an input level of IC1001 87th Exchange capstan DD unit. pin a sine wave of 2.5Vp-p or not? When playback, is a When playback, is a tension of 65th pin of tension of 3rd pin of Exchange IC1001.
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A cassette tape can't insert it Whether does WORM Investigate a front roading gear gear of a cassette roading and LOCKER. block move or not? When not inserting Investigate IC1001 to a cassette more, is investigate LED and a tension of 3, 4th photosensor of a MAIN PCB pin of IC1001 0V? and the peripheral circuit.
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When inserting cassette, it ejects immediately For whether it is a cassette Whether don't you defective product or not, enter it with an other cassette roading block cassette or not? defective product. If you cover an infrared Exchange EOT/BOT photo rays sensor, 3rd of IC1001, transister.
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Tape loading is OK, but unloads immediately Whether it takes UNREG Whether does a Investigate a power supply 12V for CP1005 2nd pin cylinder rotate or not? circuit. or not? When playback, it Whether does DC 5V pulse takes 1.3V for 5th depends on IC1001 76th pin or not ? pin of CP1005?
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When playback, a picture vertically finely shakes Whether does a noise appear for a screen or not? For tracking UP/DOWN Investigate P/B envelope. make, does a noise of a screen get with no? Whether is a height Adjust guide post height. of a guide post correct or not? Whether is PG SIFTER...
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When playback, fast forward or rewind mode is activated, unit stops immediately Whether does It refers to a clause of "Capstan capstan DD motor DD motor doesn't rotate" rotate or not? Whether does capstan belt Exchange capstan belt. normal or not? Whether there is a reel sensor pulse signal for Investigate Q1001 and R1006.
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When playback, a picture horizontally shakes Whether is FG output level of CP1005 3rd Exchange a cylinder motor. pin approximately 4.5Vp-p or not? Do you hang a load, become approximately 4V for 1.3V or Exchange IC1001. cylinders voltage of CP1005 5th pin? Exchange a cylinder motor.
TV-20F242 TV-20F242 TV-20F242 STANDARD CIRCUIT DIAGRAM NOTE ON USING CIRCUIT DIAGRAMS 1.SAFETY The Components identified by the symbol are critical for safety. For continued safety, replace safety critical components only with manufacturers recommended parts. 2.INDICATION OF PARTS SYMBOL [EXAMPLE] In the PC board...
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TV-20F242 TV-20F242 SEMICONDUCTOR BASE CONNECTIONS D I O D E CATHODE ANODE ANODE CATHODE 1SS133T-77 11E1-EIC 10ELS2N-TA1B2 SID1050CM FMV-3FULF027-102 GBL06L-6177 HZ11B3L TD 11EQS04N-TA1B2 21DQ09N-FC4 SLR-342MCT32 HZ27-1L TD 11ES1N-TA1B2 21DQ09N-TA2B1 SLR-342VCT32 MTZJ13B T-77 RD12FB-T7 RMPG06J-G3 MTZJ30B T-77 RU2AM V1 MTZJ33B T-77 MTZJ5.1B T-77...
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TV-20F242 TV-20F242 [MAIN PCB TV POWER CIRCUIT DIAGRAM] TV POWER SCHEMATIC DIAGRAM (MAIN PCB) DEGAUSS_H 6.3A 125V 2.5A 125V FROM/TO DEFLECTION CAUTION: FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, REPLACE ONLY WITH THE SAME TYPE FUSE RELAY DRIVE 6.3A 125V(F501) ,2.5A 125V(F502).
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TV-20F242 TV-20F242 [OPERATION PCB & AV PCB CIRCUIT DIAGRAM] OPERATION SCHEMATIC DIAGRAM (OPERATION PCB) FROM/TO I/O FROM/TO AV CD702 (CP4202) CD704 (CP704) CH2D001A CH2B032A FRONT VIDEO IN FRONT VIDEO IN FRONT AUDIO IN L FRONT AUDIO IN L W809 SOUND GND...
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TV-20F242 TV-20F242 [DECK PCB CIRCUIT DIAGRAM] DECK SCHEMATIC DIAGRAM LOADING MOTOR M101 (DECK PCB) S105 BOT SENSOR Q101 S106 RPT-38PB113 S101 S102 S103 S104 FROM/TO MICON CP101 (CP1006) 52044-0445 LDM+ LDM- PCB550 VE8851 NOTE: THIS SCHEMATIC DIAGRAM IS THE LATEST AT THE TIME...
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TV-20F242 TV-20F242 35 200mV 2ms/div NOTE: The following waveforms were measured at the point of the corresponding balloon number in the schematic diagram. No.51768 2-49 2-50 No.51768...
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- CHASSIS EXPLODED VIEW (TOP VIEW) - CHASSIS EXPLODED VIEW (BOTTOM VIEW) - ELECTRICAL REPLACEMENT PARTS LIST - PACKING & ACCESSORY REPLACEMENT PARTS LIST USING P.W. BOARD Model TV-20F242 P.W.B ASS'Y SYSCON PCB ASSíY X-A57202B01A OPERATION PCB ASSíY X-A57202B030 MAIN PCB ASSíY X-A57202B07A CRT PCB ASSíY...
CHASSIS REPLACEMENT PARTS LIST REF. NO. PART NO. DESCRIPTION REF. NO. PART NO. DESCRIPTION X-85OA500022 AHC ASS'Y X-8107126A04 SCREW,TAP TITE(S) PAN 2.6x10 X-85OP200290 BELT,CAPSTAN (S) X-8107226804 SCREW,TAP TITE(S) BIND 2.6x8 X-85OP900710 LEVER,REC X-8107226604 SCREW,TAP TITE(S) BIND 2.6x6 X-85OP500083 BASE,AC HEAD X-8109126604 SCREW,TAP TITE(B) PAN 2.6x6...
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CHASSIS EXPLODED VIEW (TOP VIEW) M2003 UN4001 H5001 H5002 M101 PCB550 (DECK PCB ASS'Y) NOTE: Applying positions AA, AB, AC, AD and BA for CLASS PART NO. MARK the grease or oil are displayed for this section. GREASE G-555G Check if the correct grease or oil is applied for G-488M each position.
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CHASSIS EXPLODED VIEW (BOTTOM VIEW) M2001 NOTE: Applying positions AA, AB, AC, AD and BA for CLASS PART NO. MARK the grease or oil are displayed for this section. GREASE G-555G Check if the correct grease or oil is applied for each position.
ELECTRICAL REPLACEMENT PARTS LIST ACCESSORY REPLACEMENT PARTS LIST REF. NO. PART NO. DESCRIPTION X-076G0DY010 REMOCON RM-C393G-1H X-JB5KD500 POLYBAG X-J5500115 SERVICE STATION LIST X-J5500117 REGISTRATION CARD X-J5720201 INSTRUCTION BOOK X-J5500112 GUARANTEE CARD X-J5501202 GUARANTEE CARD X-791WHA0085 LAMIFILM,BAG X-792WHA0288 PACKAGE,TOP X-792WHA0289 PACKAGE,BOTTOM X-793WCD1294 GIFT BOX...
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JVC SERVICE & ENGINEERING COMPANY OF AMERICA DIVISION OF JVC AMERICAS CORP. Head office : 1700 Valley Road, Wayne, New Jersey 07470 (973)315-5000 East Coast : 10 New Maple Avenue, Pine Brook, New Jersey 07058 (973)396-1000 Midwest 705 Enterprise St. Aurora, Illinois 60504...