Table Of Contents - JVC SR-VS20E Service Manual

Section Title
Important Safety Precautions
INSTRUCTIONS
1. DISASSEMBLY
1.1 HOW TO REMOVE THE MAJOR PARTS .................................................... 1-1
1.1.1 Introduction ............................................................................................ 1-1
1.2 HOW TO READ THE DISASSEMBLY AND ASSEMBLY .............................. 1-1
1.3 DISCONNECTION OF CONNECTORS (WIRES) ........................................ 1-1
1.4 SCREWS USED CABINET COMPONENTS AND BOARD ASSEMBLIES .......... 1-1
1.5 HOW TO REMOVE THE MAJOR PARTS <COM section> .......................... 1-2
1.5.1 Disassembly flow chart .......................................................................... 1-2
1.5.2 Disassembly/assembly method <COM section> ................................... 1-2
1.6 HOW TO REMOVE THE MAJOR PARTS <VHS section> ........................... 1-4
1.6.1 Disassembly flow chart .......................................................................... 1-4
1.6.2 DIsassembly/assembly method <VHS section> .................................... 1-4
1.7 HOW TO REMOVE THE MAJOR PARTS <DV section> .............................. 1-6
1.7.1 Disassembly flow chart .......................................................................... 1-6
1.7.2 Disassembly/assembly method <DV section> ....................................... 1-6
1.8 SERVICE POSITIONS .................................................................................. 1-8
1.8.1 Service position <VHS SIDE> ................................................................. 1-8
1.8.2 Service position <DV SIDE> .................................................................... 1-9
1.9 MECHANISM SERVICE MODE .................................................................. 1-10
1.9.1 How to set the "MECHANISM SERVICE MODE" ................................ 1-10
1.10 CONNECTION .......................................................................................... 1-11
1.11 EMERGENCY DISPLAY FUNCTION ........................................................ 1-13
1.11.1 Displaying the emergency information ................................................ 1-13
1.11.2 Clearing the emergency history ........................................................... 1-13
1.11.3 Emergency content description ........................................................... 1-14
1.11.4 Emergency detail information 1 .......................................................... 1-15
1.11.5 Emergency detail information 2 .......................................................... 1-16
2. MECHANISM ADJUSTMENT (VHS)
2.1 BEFORE STARTING REPAIR AND ADJUSTMENT ..................................... 2-1
2.1.1 Precautions ............................................................................................ 2-1
2.1.2 Checking for Proper Mechanical Operations ......................................... 2-1
2.1.3 Manually Removing the Cassette Tape ................................................. 2-1
2.1.4 Jigs and Tools Required for Adjustment ................................................. 2-2
2.1.5 Maintenance and Inspection .................................................................. 2-3
2.2 REPLACEMENT OF MAJOR PARTS ........................................................... 2-6
2.2.1 Before Starting Disassembling (Phase matching between
mechanical parts) ................................................................................... 2-6
2.2.2 How to Set the Mechanism Assembling Mode ....................................... 2-6
2.2.3 Cassette Holder Assembly ..................................................................... 2-6
2.2.4 Pinch Roller Arm Assembly .................................................................... 2-8
2.2.5 Guide Arm Assembly and Press Lever Assembly .................................. 2-8
2.2.6 Audio Control Head ................................................................................ 2-8
2.2.7 Loading Motor ........................................................................................ 2-8
2.2.8 Capstan Motor ....................................................................................... 2-9
2.2.9 Pole Base Assembly (supply or take-up side) ........................................ 2-9
2.2.10 Rotary Encoder .................................................................................. 2-10
2.2.11 Clutch Unit ......................................................................................... 2-10
2.2.12 Change Lever Assembly, Direct Gear, Clutch Gear and Coupling Gear ......... 2-10
2.2.13 Link Lever .......................................................................................... 2-11
2.2.14 Cassette Gear, Control Cam and Worm Gear ................................... 2-11
2.2.15 Control Plate ...................................................................................... 2-11
2.2.16 Loading Arm Gear (supply or take-up side) and Loading Arm Gear Shaft .......... 2-12
2.2.17 Take-up Lever, Take-up Head and Control Plate Guide .................... 2-13
2.2.18 Capstan Brake Assembly .................................................................. 2-13
2.2.19 Sub Brake Assembly (take-up side) .................................................. 2-13
2.2.20 Main Brake Assembly (take-up side), Reel Disk (take-up side)
and Main Brake Assembly (supply side) ............................................ 2-13
2.2.21 Tension Brake Assembly, Reel Disk (supply side) and
Tension Arm Assembly ...................................................................... 2-14
2.2.22 Idler Lever, Idler Arm Assembly ......................................................... 2-14
2.2.23 Stator Assembly ................................................................................. 2-14
2.2.24 Rotor Assembly ................................................................................. 2-14
2.2.25 Upper Drum Assembly ....................................................................... 2-15
2.3 COMPATIBILITY ADJUSTMENT ................................................................ 2-16
2.3.1 Checking/Adjustment of FM Waveform Linearity ................................. 2-16
2.3.2 Checking/Adjustment of the Height and Tilt of the Audio Control Head ........ 2-17
2.3.3 Checking/Adjustment of the Audio Control Head Phase (X-Value) ......... 2-17
2.3.4 Checking/Adjustment of the Standard Tracking Preset ....................... 2-18
2.3.5 Checking/Adjustment of the Tension Pole Position .............................. 2-18
MECHANISM ADJUSTMENT (DV)
2.9 PREPARATION ........................................................................................... 2-21
2.9.1 Precautions .......................................................................................... 2-21
2.9.2 Tools Required for Adjustments ........................................................... 2-21
2.9.3 Disassembly and Assembly Procedures .............................................. 2-21
2.9.4 Screws and Washers Used in Disassembly/Assembly of the
Mechanism Assembly .......................................................................... 2-21
2.10 DISASSEMBLY/ASSEMBLY OF THE MECHANISM ASSEMBLY ............. 2-22
2.10.1 Introduction ........................................................................................ 2-22
2.10.2 Mechanism Modes ............................................................................ 2-22
2.11 MECHANISM TIMING CHART .................................................................. 2-24
2.12 MECHANISM ASSEMBLY/DISASSEMBLY PROCEDURE TABLE ........... 2-25
2.13 DISASSEMBLY/ASSEMBLY ...................................................................... 2-27
2.14 LIST OF PROCEDURES FOR DISASSEMBLY ........................................ 2-35
2.15 MECHANISM DISASSEMBLY/ASSEMBLY SHEET .................................. 2-36
2.16 MECHANISM PHASE CHECK/ADJUSTMENT ......................................... 2-38
2.17 POSITIONING THE TENSION POLE ........................................................ 2-39
2.18 COMPATIBILITY AND ERROR RATE ADJUSTMENTS ............................ 2-40
2.18.1 Preparation ........................................................................................ 2-40
2.18.2 Adjustment ......................................................................................... 2-40
2.18.3 Linearity adjustment .......................................................................... 2-41
2.18.4 PB switching point adjustment ........................................................... 2-41
2.18.5 Error rate adjustment ......................................................................... 2-41
2.18.6 Error rate measuring method ............................................................. 2-41
2.19 TAPE EJECTION ....................................................................................... 2-42
The following table lists the differing points between Models (SR-VS20EK and SR-VS20E) in this series.
VIDEO SYSTEM
TUNER (BROADCASTING STANDARD)
TUNER (STEREO DECODER)
DISPLAY (LANG.)
TIMER (VCR PLUS+)
TIMER (VPS)

TABLE OF CONTENTS

Page Section
3. ELECTRICAL ADJUSTMENT (VHS)
3.1 PRECAUTION .............................................................................................. 3-1
3.1.1 Required test equipments ...................................................................... 3-1
3.1.2 Required adjustment tools ..................................................................... 3-1
3.1.3 Color (colour) bar signal,Color (colour) bar pattern ............................... 3-1
3.1.4 Switch settings and standard precautions ............................................. 3-1
3.1.5 EVR Adjustment ..................................................................................... 3-1
3.2 SERVO CIRCUIT .......................................................................................... 3-2
3.2.1 Switching point ....................................................................................... 3-2
3.2.2 Slow tracking preset ............................................................................... 3-2
3.3 VIDEO CIRCUIT ........................................................................................... 3-2
3.3.1 D/A level ................................................................................................. 3-2
3.3.2 EE Y level ............................................................................................... 3-3
3.3.3 PB Y level (S-VHS / VHS) ...................................................................... 3-3
3.3.4 REC color (colour) level ......................................................................... 3-3
3.3.5 Video EQ (Frequency response) ........................................................... 3-4
3.3.6 AUTO PICTURE initial setting ............................................................... 3-4
3.3.7 DV EE Y level ......................................................................................... 3-4
3.4 AUDIO CIRCUIT ........................................................................................... 3-5
3.4.1 Audio REC FM ....................................................................................... 3-5
3.5 SYSCON CIRCUIT [SR-VS20E] ................................................................... 3-5
3.5.1 Timer clock ............................................................................................. 3-5
ELECTRICAL ADJUSTMENT (DV)
3.6 PREPARATION ............................................................................................. 3-6
3.6.1 Precautions ............................................................................................ 3-6
3.6.2 Equipment required for adjustment ........................................................ 3-6
3.6.3 Tools required for adjustments ............................................................... 3-6
3.6.4 Setup ...................................................................................................... 3-6
4. CHARTS AND DIAGRAMS
NOTES OF SCHEMATIC DIAGRAM ................................................................... 4-1
CIRCUIT BOARD NOTES .................................................................................... 4-2
4.1 BOARD INTERCONNECTIONS ................................................................... 4-3
4.2 SWITCHING REGULATOR AND REGULATOR SCHEMATIC DIAGRAMS .......... 4-5
4.3 VIDEO/AUDIO SCHEMATIC DIAGRAM ....................................................... 4-7
4.4 SYSTEM CONTROL SCHEMATIC DIAGRAM ............................................. 4-9
4.5 SUB CPU SCHEMATIC DIAGRAM ............................................................ 4-13
4.6 TUNER SCHEMATIC DIAGRAM ................................................................ 4-15
4.7 VIDEO I/O SWITCH SCHEMATIC DIAGRAM ............................................ 4-17
4.8 AUDIO I/O SCHEMATIC DIAGRAM ........................................................... 4-19
4.9 CONNECTION SCHEMATIC DIAGRAM .................................................... 4-21
4.10 3D DIGITAL/2M SCHEMATIC DIAGRAM ................................................. 4-23
4.11 TERMINAL SCHEMATIC DIAGRAM ........................................................ 4-25
4.12 DEMODULATOR SCHEMATIC DIAGRAM .............................................. 4-27
4.13 S-SUB SCHEMATIC DIAGRAM ............................................................... 4-29
4.14 MDA SCHEMATIC DIAGRAM .................................................................. 4-31
4.15 PRE/REC SCHEMATIC DIAGRAM .......................................................... 4-33
4.16 ON SCREEN SCHEMATIC DIAGRAM ..................................................... 4-35
4.17 DISPLAY, EJECT SW, LED/SW, JACK AND JOG SCHEMATIC DIAGRAMS ......... 4-37
4.18 DV SYSTEM CONTROL SCHEMATIC DIAGRAM ................................... 4-39
4.19 DV MSD SCHEMATIC DIAGRAM ............................................................ 4-41
4.20 DV MAIN SCHEMATIC DIAGRAM ........................................................... 4-43
4.21 DV I/O SCHEMATIC DIAGRAM ............................................................... 4-45
4.22 DV V OUT SCHEMATIC DIAGRAM ......................................................... 4-47
4.23 AUDIO AD/DA SCHEMATIC DIAGRAM ................................................... 4-49
4.24 DV DSP SCHEMATIC DIAGRAM ............................................................. 4-51
4.25 SWITCHING REGULATOR AND REGULATOR CIRCUIT BOARDS .......... 4-53
4.26 3D DIGITAL/2M AND S-SUB CIRCUIT BOARDS .................................... 4-55
4.27 TERMINAL CIRCUIT BOARD .................................................................. 4-56
4.28 MAIN CIRCUIT BOARD ........................................................................... 4-57
4.29 DEMODULATOR AND ON SCREEN CIRCUIT BOARDS ........................ 4-60
4.30 DISPLAY, EJECT SW, JACK, LED/SW AND JOG CIRCUIT BOARDS .......... 4-61
4.31 PRE/REC MDA CIRCUIT BOARD ............................................................ 4-63
4.32 DV MAIN CIRCUIT BOARD ..................................................................... 4-65
4.33 FDP GRID ASSIGNMENT AND ANODE CONNECTION ......................... 4-71
4.34 REMOTE CONTROL SCHEMATIC DIAGRAM ........................................ 4-72
4.35 WAVEFORMS ........................................................................................... 4-73
4.36 VOLTAGE CHARTS .................................................................................. 4-75
4.37 CPU PIN FUNCTION ................................................................................ 4-78
4.38 SYSTEM CONTROL BLOCK DIAGRAM (VHS) ....................................... 4-79
4.39 VIDEO BLOCK DIAGRAM(VHS) .............................................................. 4-81
4.40 AUDIO BLOCK DIAGRAM (VHS) ............................................................. 4-85
4.41 SYSTEM CONTROL BLOCK DIAGRAM (DV) ......................................... 4-87
4.42 VIDEO BLOCK DIAGRAM (DV) ............................................................... 4-89
5. PARTS LIST
5.1 PACKING AND ACCESSORY ASSEMBLY <M1> ....................................... 5-1
5.2 FINAL ASSEMBLY <M2> ............................................................................. 5-2
5.3 MECHANISM ASSEMBLY (VHS) <M3> ...................................................... 5-4
5.4 MECHANISM ASSEMBLY (DV) <M4> ......................................................... 5-6
5.5 ELECTRICAL PARTS LIST ........................................................................... 5-8
SW REGULATOR BOARD ASSEMBLY <01> ................................................... 5-8
REGULATOR BOARD ASSEMBLY <02> .......................................................... 5-9
MAIN BOARD ASSEMBLY <03> ..................................................................... 5-10
3D DIGITAL/2M BOARD ASSEMBLY <05> ..................................................... 5-18
TERMINAL BOARD ASSEMBLY <06> ............................................................ 5-19
AUDIO CONTROL HEAD BOARD ASSEMBLY <12> ..................................... 5-21
DEMOD BOARD ASSEMBLY <14> ................................................................. 5-21
S-SUB BOARD ASSEMBLY <15> ................................................................... 5-22
DV PRE/REC MDA BOARD ASSEMBLY <16> ............................................... 5-23
ON SCREEN BOARD ASSEMBLY <17> ......................................................... 5-24
EJECT SW BOARD ASSEMBLY <27> ............................................................ 5-25
SW/DISPLAY BOARD ASSEMBLY <28> ........................................................ 5-25
JACK BOARD ASSEMBLY <36> ..................................................................... 5-26
LED/SW BOARD ASSEMBLY <47> ................................................................ 5-26
DV MAIN BOARD ASSEMBLY <50> ............................................................... 5-26
LOADING MOTOR BOARD ASSEMBLY <55> ............................................... 5-32
JOG BOARD ASSEMBLY <85> ....................................................................... 5-32
SR-VS20EK
PAL/NTSC PB ON PAL TV
I
NICAM
ENGLISH
VIDEO PLUS+ DELUXE
NOT USED
Title
SR-VS20E
PAL/MESECAM(MANUAL)/NTSC PB ON PAL TV
B/G, D/K
NICAM/A2
3 LANGUAGE
SHOW VIEW DELUXE
USED
Page