Yamaha kx 493

Page 1

STEREO CASSETTE DECK

KX-393/493

SERVICE MANUAL

IMPORTANT NOTICE

This manual has been provided for the use of authorized YAMAHA Retailers and their service personnel.
it has been assumed that basic service prooedures inherant to the industry, and more specifically YAMAHA Products. are already
known and understood by the users, and have therefore not been restated.

WARNING: Failure to follow appropriate senior: and safety procedures when servicing this product may result in personal
injury, destruction of expensive components and failure of the product to perform as specified. For these reasons.
we advise all YAMAHA product owners that all service required should be performed by an authorized
YAMAHA Retailer or the appointed service representative,

IMPORTANT: The presentation or sale of this manual to any individual or firm does not constitute authorization, certification or
recognition of any applicable technical capabilities, or establish a principle-agent relationship of any form.

The data provided is believed to be accurate and applicable to the unit(s) indicated on the cover. The research, engineering. and
service depanments of YAMAHA are continually striving to improve YAMAHA products. Modifications are. therefore. inevitable
and specifications are subject to change without notice or obligation to retrofit. Should any discrepancy appear to exist. please contact
the distributors Service Division.

WARNING: Static discharges can destroy expensive components. Discharge any static electricity your body may have accumu»
later] by grounding yourself to the ground buss in the unit (heavy gauge black wires connect to this buss).
IMPORTANT: Turn the unit OFF during disassembiy and parts replacement, Recheck all work before you apply power to the unit.

» I CONTENTS

TO SERVICE PERSONNEL ..... 1 DISPLAY DATA

. FRONT PANELS . 1 KX-393 BLOCK DIAGRAM
REAR PANEL . 2 KX-493 BLOCK DIAGRAM .......
SPECIFICATIONS . 3 KX-393 PRINTED CIRCUIT BOARD.
INTERNAL VIEW 4 KX-493 PRINTED CIRCUIT BOARD.

DISASSEMBLY pnoceounes
ADJUSTMENTS
u-com DATA

5~7 KX-393 SCHEMATIC DIAGRAM....
. 8~11 KX-493 SCHEMATIC DIAGRAM 27
. 12~14 PARTS LIST... 28~45

1 0 0 62 0 YAMAHA CORPORATiON

P.O.Box1,Hamamatsu,Japan
2.82K-724 in 6) Printed in Japan 98.l

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KX-393/493

I TO SERVICE PERSONNEL

1. Critical Components lntormatlcn. .
Components having special characteristics are marked A
and must be replaced with parts having specifications equal
to those originally installed.

2. Leakage Current Measurement (For 120V Models Only).
When service has been completed. it is imperative to verity
that all exposed conductive surfaces are properly insulated
from supply circuits.

0 Meter impedance should be equivalent to 1500 chm shunted
by 0.15mi

AC LEAKAGE

WALL EQUIPMENT TESTER OR
OUTLET UNDER TEST EQUIVALENT

@3-

;

INSULATING
TABLE
0 Leakage current must not exceed 0.5mA.

0 Be sure to test for leakage with the AC plug in both
polarities.

WARNING: CHEMICAL CONTENT NOTICE!

The solder used in the production of this product contains LEAD. In addition, other electrical/electronic
and/or plastic (where applicable) components may also contain traces of chemicals found by the
California Health and Welfare Agency (and possibly other entities) to cause cancer and/or birth defects

or other reproductive harm.

DO NOT PLACE SOLDER, ELECTRICAL/ELECTRONIC OR PLASTIC COMPONENTS IN YOUR MOUTH

FOR ANY REASON WHATSOEVER!

Avoid prolonged, unprotected contact between solder and your skin! When soldering, do not inhale

solder fumes or expose eyes to solder/flux vapor!

If you come in contact with solder or components located inside the enclosure of this product, wash your

hands before handling food.

I FRONT PANELS

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