GE micro started humming, no heat. I'm not too clear on how to test the HV diode and the capacitor (both look fine). Connect the meter leads to what? I've read it's most likely the magnetron. Should I just go ahead and replace it or do I have to test the diode and capacitor?

Also, inside the unit it lists model PVM2070 and I believe the magnetron part is # WB27X10939. However, the wiring diagram folded up inside the case say the magnetron part is # WB27X10735. The magnetron says Samsung OM75P (10) on it's label. I have found those online, but with a different GE part number. Which is correct?