JVC HR-J790KR Service Manual

SERVICE MANUAL

VIDEO CASSETTE RECORDER

HR-J790KR

Regarding service information other than these sections, refer to the HR-VP690U service manual (No. 82841). Also, be sure to note important safety precautions provided in the service manual.

This service manual is printed on 100% recycled paper.

No. 82926

July 2002

DIFFERENT TABLE .............................................................................................................................................................................................................. 1

4. CHARTS AND DIAGRAMS (4-1 to 4-22)

4.1 BOARD INTERCONNECTIONS .................................................................................................................................................................................. 4-1

4.2 MAIN (VIDEO/AUDIO) SCHEMATIC DIAGRAM ......................................................................................................................................................... 4-3

4.3 MAIN (SYSCON) SCHEMATIC DIAGRAM .................................................................................................................................................................. 4-5

4.4 MAIN (SW.REG) SCHEMATIC DIAGRAM................................................................................................................................................................... 4-7

4.5 MAIN (TUNER/DEMOD) SCHEMATIC DIAGRAM ...................................................................................................................................................... 4-9

4.6 MAIN (FRONT) SCHEMATIC DIAGRAM ................................................................................................................................................................... 4-11

4.7 MAIN (TERMINAL) SCHEMATIC DIAGRAM ............................................................................................................................................................. 4-13

4.8 MAIN (BS CONNECTION) AND R.PAUSE SCHEMATIC DIAGRAMS ...................................................................................................................... 4-15

4.9 DEMODULATOR SCHEMATIC DIAGRAM ................................................................................................................................................................ 4-17

4.10 MAIN AND R.PAUSE CIRCUIT BOARDS ............................................................................................................................................................... 4-19

4.11 DEMODULATOR CIRCUIT BOARD ........................................................................................................................................................................ 4-22

5. PARTS LIST (5-1 to 5-8)

5.1 PACKING AND ACCESSORY ASSEMBLY <M1> ....................................................................................................................................................... 5-1

5.2 FINAL ASSEMBLY <M2> ............................................................................................................................................................................................ 5-2

5.3 ELECTRICAL PARTS LIST ......................................................................................................................................................................................... 5-4

The following table indicate main different points between models HR-VP690U and HR-J790KR.

ITEM

COSMETIC/COLOR MOLD-BLACK HEAD CLEANER NO YES F-1IN (COLOR) L-1IN(COLOR) NO V,LR(SLV/Y,W,R) BACKUP TIME — 3MIN

MODEL

HR-VP690U HR-J790KR

PNT PURE/SILVER

V,LR(SLV/BLACK)

V,LR(SLV/Y,W,R)

The following table indicate different parts number between models HR-VP690U and HR-J790KR

PACKING AND ACCESSORY ASSEMBLY <M1>

PACKING AND ACCESSORY ASSEMBLY <M1> is indicated on the parts list.

FINAL ASSEMBLY <M2>

FINAL ASSEMBLY <M2> is indicated on the parts list.

MECHANISM ASSEMBLY <M4>

REF MODEL

NO. ITEM

HR-VP690U HR-J790KR

1 MAIN DECK ASSY LP20821-006A *LP20821-006B 5

GUIDE POLE(SUPPLY)

TENSION STUD BASE ASSY

LP40098-001B *LP40701-001A

LP40637-002A *LP40637-002B 25 PIN LP40100-001A *LP40100-002A 61 MOTOR GUIDE LP30230-001B *LP30230-003D 69 CONTROL PLATE LP10201-003E *LP10201-003G 72 TENSION ARM ASSY LP40108-002A *LP40108-001A 88 IDLER ARM ASSY LP40114-012A *LP40114-011B 90 CLUTCH UNIT 3 LP40593-001A *LP40593-003C 114 RELAY GEAR LP30242-002A *LP30242-002B 115 OPENER GUIDE LP30339-002E *LP30339-002F

MAIN BOARD ASSEMBLY <03>

REF MODEL

NO. ITEM

PW1 MAIN BOARD ASSY LPA10130-04C1 LPA10141-01B1

DEMOD BOARD ASSEMBLY <14>

REF MODEL

NO. ITEM

PW1 DEMOD BOARD ASSY — LPA10094-06B

MINI FRONT BOARD ASSEEMBLY <28>

REF MODEL

NO. ITEM

PW6

MINI FRONT BOARD ASSY

119 DRIVE GEAR LP30243-001D *LP30243-002A 122 SIDE HOLDER(L) LP10081-002L *LP10081-002P 123 SIDE HOLDER(R) LP10082-002M *LP10082-002V

Notes : Mark — is not used.

124 LOOK LEVER(L) LP30255-006A *LP30255-006B 151 DOOR OPENER LP20324-003B LP20324-003C

HR-VP690U HR-J790KR

LPA10130-01A6 —

Mark * reference model was also changed.

SECTION 3

ELECTRICAL ADJUSTMENT

As for the following items, adjustment is not required in this model as follows.

Delete

3.4 Demodulator circuit

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JVC HR-J790KR Service Manual

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