Panasonic NN-K153WF, Service Manual

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4. An open capacitor will show constant 9M .
5. Resistance between each terminal and chassis should be infinite.
9.5. Magnetron
Continuity checks can only indicate an open filament or a shorted magnetron. To diagnose for
an open filament or shorted magnetron:
1. Isolate magnetron from the circuit by disconnecting the leads.
2. A continuity check across magnetron filament terminals should
indicate one ohm or less.
3. A continuity check between each filament terminal and magnetron
case should read open.
9.6. Diode
1. Isolate the diode from the circuit by disconnecting the leads.
2. With the ohmmeter set on the highest resistance scale, measure
the resistance across the diode terminals.Reverse the meter leads
and again observe the resistance reading.Meter with 6V, 9V or
higher voltage batteries should be used to check the front-to-back
resistance of the diode, otherwise an infinite resistance may be
read in both directions. / A normal diode’s resistance will be
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