Sharp VC-90ET User Manual

VC-90ET
SHARP
SERVICE
MANUAL
VIDEO
CASSETTE
RECORDER
move.
VC-90ET
In
the
interests
of
user-safety
(Required
by
safety
regulations
in
some
countries)
the
set
should
be
restored
to
its
original
condition
and
only
parts
identical to those specified should be used.
CONTENTS
SPECIFICATIONS.
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DISASSEMBLY
AND
REASSEMBLY...........ccssesscsscsecsscrececeeneesneeseeserseeseserscsvenseeseneeesenenaes
FUNCTION
OF
MAJOR
MECHANICAL
ADJUSTMENT, REPLACEMENT AND ASSEMBLY
OF
MECHANICAL
UNITS
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ses
ADJUSTMENT
OF
ELECTRICAL
CIRCUITRY
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TROUBLESHOOTING
GUIDE
BLOCK
DIAGRAM
WAVE
FORMS
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SCHEMATIC
DIAGRAMS
WIRING
SIDE
PWBS
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REPLACEMENT
ELECTRICAL
PARTS
LIST
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EXPLODED
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PACKING
OF
THE
SET
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SHARP CORPORATION

Sharp VC-90ET Specifications

General

Brand	Sharp
Model	VC-90ET
Category	VCR
Language	English

Summary

SPECIFICATIONS

DISASSEMBLY AND REASSEMBLY

FUNCTION OF MAJOR MECHANICAL PARTS

TOP VIEW

Details the top view of major mechanical parts with labeled components.

BOTTOM VIEW

Details the bottom view of major mechanical parts with labeled components.

ADJUSTMENT, REPLACEMENT AND ASSEMBLY OF MECHANICAL UNITS

MECHANICAL PARTS REQUIRING PERIODICAL INSPECTION

REMOVAL AND REASSEMBLY OF CASSETTE HOUSING CONTROL ASSEMBLY

REPLACEMENT OF MASTER CAM

Procedure for replacing the master cam assembly in the cassette housing.

REPLACEMENT AND HEIGHT CHECKING AND ADJUSTMENT OF REEL DISKS

CHECKING AND ADJUSTMENT OF TAKE-UP TORQUE IN FAST FORWARD MODE

Procedure for checking and adjusting take-up torque in fast forward mode.

REPLACEMENT OF MAIN BRAKE

REPLACEMENT OF A/C (Audio/Control) HEAD

ADJUSTMENT OF THE ELECTRICAL CIRCUITRY

ADJUSTMENT OF SYSTEM CONTROL / SERVO CIRCUIT

Details adjustments for system control and servo circuits, including test points.

ADJUSTMENT OF Y/C CIRCUIT

ADJUSTMENT OF Hi-FI / LINER AUDIO CIRCUIT

ADJUSTMENT OF IF CIRCUIT

MECHANISM TROUBLESHOOTING

FF/REW FAILURE (NO TAPE WINDING)

Troubleshooting steps for FF/REW failure due to no tape winding.

POWER TROUBLESHOOTING

INFRARED R/C TROUBLESHOOTING

CASSETTE CONTROL TROUBLESHOOTING

LOADING MOTOR AND EJECT TROUBLESHOOTING

CAPSTAN MOTOR TROUBLESHOOTING

DRUM SERVO TROUBLESHOOTING

PLAYBACK MODE (LUMINANCE) TROUBLESHOOTING

E-E MODE TROUBLESHOOTING

OVERALL BLOCK DIAGRAM

SYSTEM CONTROL BLOCK DIAGRAM

SCHEMATIC DIAGRAM

WAVE FORMS

MAIN CIRCUIT (1)

PRINTED WIRING BOARD ASSEMBLIES

TIMER PWB

Printed wiring board layout for the Timer PWB.

OPERATION PWB

Printed wiring board layout for the Operation PWB.

HiFi PWB

Printed wiring board layout for the HiFi PWB.

POWER PWB

Printed wiring board layout for the Power PWB.

SYSTEM CONTROL/SERVO PWB

Printed wiring board layout for the System Control/Servo PWB.

NTSC SKEW PWB

Printed wiring board layout for the NTSC Skew PWB.

SUB CHROMA (SECAM) PWB

Printed wiring board layout for the Sub Chroma (SECAM) PWB.

REPLACEMENT PARTS LIST PARTS REPLACEMENT

MAIN CIRCUIT

List of replacement parts for the main circuit.

TRANSISTORS

List of replacement transistor parts.

INFRARED REMOTE CONTROL CIRCUIT

CABINET PARTS

List of replacement parts for the infrared remote control circuit cabinet.

MECHANISM CHASSIS PARTS

PACKING OF THE SET