Table Of Contents - JVC HM-HDS1U Service Manual

Section Title
Hard Disk Drive (HDD)
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 <HDD section> ............................ 1-6
1.7.1 Disassembly flow chart .................................................................. 1-6
1.7.2 DIsassembly/assembly method <HDD section> ............................ 1-6
1.8 SERVICE POSITIONS .................................................................................. 1-7
1.8.1 Service position <VHS SIDE> ........................................................ 1-7
1.8.2 Service position <HDD side> ......................................................... 1-8
1.9 MECHANISM SERVICE MODE .................................................................... 1-9
1.9.1 How to set the "MECHANISM SERVICE MODE" .......................... 1-9
1.10 CONNECTION .................................................................................. 1-10
1.11 EMERGENCY DISPLAY FUNCTION ................................................ 1-12
1.11.1 Displaying the emergency information ........................................ 1-12
1.11.2 Clearing the emergency history ................................................... 1-12
1.11.3 Emergency content description ................................................... 1-13
1.11.4 Emergency detail information 1 ................................................. 1-14
1.11.5 Emergency detail information 2 ................................................. 1-15
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
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

TABLE OF CONTENTS

Page Section
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
3.4 DIGITAL CIRCUIT ......................................................................................... 3-4
3.4.1 HDD EE Y level .............................................................................. 3-4
3.4.2 HDD PB Y level .............................................................................. 3-5
3.4.3 HDD PB C burst level ..................................................................... 3-5
3.5 AUDIO CIRCUIT ........................................................................................... 3-5
3.5.1 Audio REC FM ............................................................................... 3-5
3.6 DEMODULATOR CIRCUIT ........................................................................... 3-6
3.6.1 Input level ....................................................................................... 3-6
3.6.2 Stereo VCO .................................................................................... 3-6
3.6.3 Stereo filter ..................................................................................... 3-6
3.6.4 Separation - 1 ................................................................................. 3-6
3.6.5 Separation - 2 ................................................................................. 3-7
3.6.6 SAP VCO ....................................................................................... 3-7
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 VIDEO I/O SWITCH SCHEMATIC DIAGRAM ............................................ 4-13
4.6 AUDIO I/O SCHEMATIC DIAGRAM ............................................................ 4-15
4.7 CONNECTION SCHEMATIC DIAGRAM .................................................... 4-17
4.8 TUNER SCHEMATIC DIAGRAM ................................................................ 4-19
4.9 3D DIGITAL/2M SCHEMATIC DIAGRAM ................................................... 4-21
4.10 TERMINAL SCHEMATIC DIAGRAM ........................................................ 4-23
4.11 DEMODULATOR SCHEMATIC DIAGRAM ............................................... 4-25
4.12 S-SUB SCHEMATIC DIAGRAM ............................................................... 4-27
4.13 ON SCREEN SCHEMATIC DIAGRAM ..................................................... 4-29
4.14 EJECT SW, DIAPLAY, JACK, LED/SW AND LED SCHEMATIC DIAGRAMS .. 4-31
4.15 DIGITAL P.SUP SCHEMATIC DIAGRAM .................................................. 4-33
4.16 DIGITAL VIDEO SCHEMATIC DIAGRAM ................................................. 4-35
4.17 DIGITAL AUDIO SCHEMATIC DIAGRAM ................................................ 4-37
4.18 DIGITAL MPEG DEC SCHEMATIC DIAGRAM ......................................... 4-39
4.19 DIGITAL MPEG ENC SCHEMATIC DIAGRAM ......................................... 4-41
4.20 DIGITAL ASIC IF SCHEMATIC DIAGRAM ............................................... 4-43
4.21 SWITCHING REGULATOR AND REGULATOR CIRCUIT BOARDS ....... 4-45
4.22 3D DIGITAL/2M AND S-SUB CIRCUIT BOARDS .................................... 4-47
4.23 TERMINAL CIRCUIT BOARD .................................................................. 4-48
4.24 EJECT SW, DISPLAY, LED/SW, JACK AND LED CIRCUIT BOARDS ..... 4-49
4.25 MAIN CIRCUIT BOARD ........................................................................... 4-51
4.26 DEMODULATOR AND ON SCREEN CIRCUIT BOARDS ........................ 4-54
4.27 DIGITAL CIRCUIT BOARD ....................................................................... 4-55
4.28 FDP GRID ASSIGNMENT AND ANODE CONNECTION ........................ 4-58
4.29 REMOTE CONTROL SCHEMATIC DIAGRAM ........................................ 4-58
4.30 WAVEFORMS ........................................................................................... 4-59
4.31 VOLTAGE CHARTS .................................................................................. 4-61
4.32 CPU PIN FUNCTION ................................................................................ 4-64
4.33 SYSTEM CONTROL BLOCK DIAGRAM (VHS) ....................................... 4-65
4.34 AUDIO BLOCK DIAGRAM ........................................................................ 4-67
4.35 VIDEO BLOCK DIAGRAM(VHS) .............................................................. 4-69
4.36 VIDEO/AUDIO BLOCK DIAGRAM (HDD) ................................................ 4-73
5. PARTS LIST
5.1 PACKING AND ACCESSORY ASSEMBLY <M1> ....................................... 5-1
5.2 FINAL ASSEMBLY <M2> ............................................................................. 5-2
5.3 MECHANISM ASSEMBLY <M3> .................................................................. 5-4
5.4 ELECTRICAL PARTS LIST ........................................................................... 5-6
SW REGULATOR BOARD ASSEMBLY <01> ........................................... 5-6
REGULATOR BOARD ASSEMBLY <02> ................................................. 5-7
MAIN BOARD ASSEMBLY <03> .............................................................. 5-8
3D DIGITAL/2M BOARD ASSEMBLY <07> ............................................ 5-15
TERMINAL BOARD ASSEMBLY <06> ................................................... 5-16
A/C HEAD BOARD ASSEMBLY <12> .................................................... 5-17
DEMOD BOARD ASSEMBLY <14> ........................................................ 5-17
S-SUB BOARD ASSEMBLY <15> .......................................................... 5-17
ON SCREEN BOARD ASSEMBLY <17> ................................................ 5-18
EJECT SW BOARD ASSEMBLY <27> ................................................... 5-19
SW/DISPLAY BOARD ASSEMBLY <28> ................................................ 5-19
JACK BOARD ASSEMBLY <36> ............................................................ 5-20
LED/SW BOARD ASSEMBLY <47> ....................................................... 5-20
DIGITAL BOARD ASSEMBLY <50> ........................................................ 5-20
LOADING MOTOR BOARD ASSEMBLY <55> ....................................... 5-25
LED BOARD ASSEMBLY <90> .............................................................. 5-25
Title Page