Sharp R-426LS

CONTENTS
PRECAUTIONS TO BE OBSERVED BEFORE
AND DURING SERVICING TO AVOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROWAVE ENER-
GY
CHAPTER 1. WARNING TO SERVICE PERSON-
NEL
[1] Before Servicing.......................................... 1-1
[2] When the testing is completed,................... 1-1
[3] After repairing.............................................. 1-1
CHAPTER 2. MICROWAVE MEASUREMENT
PROCEDURE
[1] Requirements:............................................. 2-1
[2] Preparation for testing:................................ 2-1
[3] Leakage test: .............................................. 2-1
CHAPTER 3. FOREWORD AND WARNING
[1] FOREWORD............................................... 3-1
[2] WARNING................................................... 3-1
[3] DANGER..................................................... 3-1
CHAPTER 4. PRODUCT DESCRIPTION
[1] SPECIFICATIONS ...................................... 4-1
CHAPTER 5. GENERAL INFORMATION
[1] GROUNDING INSTRUCTIONS.................. 5-1
[2] OVEN DIAGRAM ........................................ 5-1
CHAPTER 6. OPERATION
[1] DESCRIPTION OF OPERATING SE-
QUENCE .................................................... 6-1
[2] OVEN SCHEMATIC.................................... 6-2
[3] DESCRIPTION AND FUNCTION OF
COMPONENTS .......................................... 6-3
CHAPTER 7. TROUBLESHOOTING GUIDE
[1] TROUBLESHOOTING CHART ................. 7-1
CHAPTER 8. TEST PROCEDURES
[1] Procedure A: MAGNETRON ASSEM-
BLY TEST ................................................... 8-1
[2] Procedure B: POWER TRANSFORMER
TEST........................................................... 8-1
[3] Procedure C: HIGH VOLTAGE RECTIFI-
ER TEST..................................................... 8-1
[4] Procedure D: HIGH VOLTAGE CAPACI-
TOR TEST .................................................. 8-2
[5] Procedure E: TEMPERATURE FUSE
OR THERMAL CUT-OUT TEST ................. 8-2
[6] Procedure F: PRIMARY INTERLOCK
SWITCH TEST............................................ 8-2
[7] Procedure F: SECONDARY INTER-
LOCK SYSTEM TEST ................................ 8-3
[8] Procedure G: MONITOR SWITCH TEST..... 8-3
[9] Procedure H: BLOWN MONITOR FUSE
TEST........................................................... 8-4
[10] Procedure I: NOISE FILTER TEST............. 8-4
[11] Procedure J: TOUCH CONTROL PANEL
ASSEMBLY TEST....................................... 8-4
[12] Procedure K: KEY UNIT TEST ................... 8-5
[13] Procedure L: RELAY TEST......................... 8-6
[14] Procedure M: DEFROST TEST .................. 8-6
[15] Procedure N: FOIL PATTERN ON THE
PRINTED WIRING BOARD TEST.............. 8-6
[16] Procedure O: AH SENSOR TEST .............. 8-7
CHAPTER 9. TOUCH CONTROL PANEL ASSEM-
BLY
[1] OUTLINE OF TOUCH CONTROL PAN-
EL ............................................................... 9-1
[2] ABSOLUTE HUMIDITY SENSOR CIR-
CUIT............................................................ 9-1
[3] SERVICING FOR TOUCH CONTROL
PANEL ........................................................ 9-2
CHAPTER 10. PRECAUTIONS FOR USING LEAD-
FREE SOLDER
[1] Employing lead-free solder ....................... 10-1
[2] Using lead-free wire solder ....................... 10-1
[3] Soldering................................................... 10-1
CHAPTER 11. COMPONENT REPLACEMENT
AND ADJUSTMENT PROCEDURE
[1] WARNINGS ...............................................11-1
[2] OUTER CASE REMOVAL .........................11-2
[3] POWER TRANSFORMER REMOVAL ......11-2
[4] HIGH VOLTAGE RECTIFIER AND HIGH
VOLTAGE CAPACITOR REMOVAL...........11-2
[5] MAGNETRON REMOVAL .........................11-2
[6] OVEN LAMP REMOVAL............................11-3
[7] POSITIVE LOCK CONNECTOR (NO-
CASE TYPE) REMOVAL ...........................11-3
[8] CONTROL PANEL ASSEMBLY RE-
MOVAL.......................................................11-3
[9] GRAPHIC SHEET AND MEMBRANE
SWITCH REPLACEMENT.........................11-3
[10] TURNTABLE MOTOR REMOVAL .............11-4
[11] COOLING FAN MOTOR REMOVAL..........11-4
[12] DOOR SENSING SWITCH/PRIMARY
INTERLOCK SWITCH AND MONITOR
SWITCH REMOVAL...................................11-5
[13] DOOR SENSING SWITCH/PRIMARY
INTERLOCK SWITCH AND MONITOR
SWITCH ADJUSTMENT............................11-5
[14] DOOR REPLACEMENT ............................11-5
CHAPTER 12. CIRCUIT DIAGRAMS
[1] Pictorial Diagram (Figure S-1) .................. 12-1
[2] Control Panel Circuit (Figure S-2)............. 12-2
[3] Printed Wiring Board (Figure S-3)............. 12-3
Parts List