Sharp R-408LS, Service Manual

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CONTENTS
PRECAUTIONS TO BE OBSERVED BEFORE
AND DURING SERVICING TO AVOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROWAVE ENER-
GY
BEFORE SERVICING
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] A: MAGNETRON ASSEMBLY TEST .......... 8-1
[2] B: POWER TRANSFORMER TEST ........... 8-1
[3] C: HIGH VOLTAGE RECTIFIER TEST....... 8-1
[4] D: HIGH VOLTAGE CAPACITOR TEST..... 8-2
[5] E: TEMPERATURE FUSE OR THER-
MAL CUT-OUT TEST ................................. 8-2
[6] F: PRIMARY INTERLOCK SWITCH
TEST........................................................... 8-2
[7] F: SECONDARY INTERLOCK SYSTEM
TEST........................................................... 8-3
[8] G: MONITOR SWITCH TEST ..................... 8-3
[9] H: BLOWN MONITOR FUSE TEST ........... 8-4
[10] I: NOISE FILTER TEST .............................. 8-4
[11] J: TOUCH CONTROL PANEL ASSEM-
BLY TEST ................................................... 8-4
[12] K: KEY UNIT TEST..................................... 8-5
[13] L: RELAY TEST .......................................... 8-5
[14] M: DEFROST TEST.................................... 8-6
[15] N: FOIL PATTERN ON THE PRINTED
WIRING BOARD TEST............................... 8-6
CHAPTER 9. TOUCH CONTROL PANEL ASSEM-
BLY
[1] OUTLINE OF TOUCH CONTROL PAN-
EL ............................................................... 9-1
[2] SERVICING FOR TOUCH CONTROL
PANEL ........................................................ 9-1
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] TURNTABLE MOTOR REMOVAL .............11-3
[9] COOLING FAN MOTOR REMOVAL..........11-3
[10] CONTROL PANEL ASSEMBLY RE-
MOVAL.......................................................11-4
[11] GRAPHIC SHEET AND MEMBRANE
SWITCH REPLACEMENT.........................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