Sharp R-420BK Service Manual

R-420BK
R-420BW
SHARF?
SERVICE MANUAL
S28M104R420BE
MICROWAVE OVEN MODELS
R-420BK / R-420BW
In the interest of user-safety the oven is to be restored
to its original condition and only the parts identical to
those specified should be used.
WARNING TO SERVICE PERSONNEL: Microwave
ovens contain circuitry capable of producing
very high voltage and current. Contact with the
following parts may result in a severe, possibly
fatal electrical shock.(High Voltage Capacitor,
High Voltage Power Transformer, Magnetron,
High Voltage Rectifier Assembly, High Voltage
Harness etc..)
TABLE OF CONTENTS
SECTION
PAGE
PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICE TO
AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY. ........... Inside Front Cover
Before Servicing .............................................................
Inside Front Cover
Warning to Service Personnel .................................................................
1
Forewordandwarning .......................................................................
2
Specifications
...............................................................................
3
Generallnformation .........................................................................
4
KeyUnitLayout .............................................................................
5
Operation ..................................................................................
6
Servicing and Troubleshooting Guide
..........................................................
9
TestProcedures
............................................................................
11
TouchControlOutline .......................................................................
21
Component Replacement and Adjustment Procedure
...........................................
25
Microwave Measurement Procedure
.......................................................... 35
Wiring/Schematic Diagram ..................................................................
36
Parts .....................................................................................
41
Packing and Accessories ....................................................................
46
SHARP ELECTRONICS CORPORATION
Service Headquarters: Sharp Plaza, Mahwah, New Jersey, 07430-2135