Microwave portion of micro/oven combo making a growling noise when turned on, lights up, turntable turns, can't see fan turning in back but may be only when hot when sensor kick on?. From what I glean from forums this can only be the magnetron which is usually replace with the power diode at the same time. Just want to make sure before purchasing since it is very expensive, could it also be a hi voltage capacitor or transformer? or no since the power is running, also 2003 model, will this have the slow discharge of the magnetron, ie. unplug and leave it for a half hour, since I do not want to get killed changing this, will a regular screwdriver joined across the capacitor protect me as long as I don't touch the metal part to discharge?, isn't the plastic part of the screwdriver a conductor? thanks