My Samsung has packed up - the fuse between the Magnetron and Capacitors has blown (5000V 0.8 A) . Before I replace it, I want to run some tests to find the cause. Any ideas - I can check for shorts, etc - there doesn't seem to be much more to the circuit though. I don't really want to replace it - its a combi microwave/oven/grill, 900W and is a major workhorse in the kitchen.