(TROUBLE 3) No microwave oscillation even though fan motor rotates.
CONDITION |
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No |
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| Check continuity of high |
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| Continuity | |
microwave |
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oscillation |
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| voltage capacitor terminals |
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| with wires removed |
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| Check continuity of high voltage |
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| Continuity in |
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| rectifier in forward and backward |
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| backward |
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| direction with DC megger |
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| direction |
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| Connect megger leads to mag- |
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| Continuity |
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| netron terminal and magnetron |
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| body |
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| Check resistance of primary and |
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| 0 Ω or ∞ |
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| secondary coil of high voltage |
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| transformer |
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| Check continuity of magnetron |
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| No |
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| Continuity | |
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| with wires removed |
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| Check continuity of filament termi- |
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| No |
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| Continuity | |
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| nal of high voltage transformer |
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| Check D.C. voltage being sup- |
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| 0 V |
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| plied to RELAY (RY1) coil |
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| Approx |
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| 15 VDC |
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CAUSE
Defective high voltage trans- former
Defective high voltage rectifier
Defective mag-
netron
Defective high voltage trans- former
Defective mag-
netron
Defective high voltage trans- former
Defective touch
control circuit
Faulty
contacts or
RELAY (RY1)
or open
relay coil
REMEDY
Replace
Replace
Replace
Replace
Replace
Replace
Replace
Replace
20