So we replace all of our appliances in early 2008 including our $450 over the range microwave oven. It is a Frigidaire Professional Series. We are a family of 4 and are light on our appliances. So yesterday my wife said that the microwave made a loud bang and now when you turn it on, it makes a loud buzzing and does not heat anything up any longer. So the trouble shooters on the internet say it is one of three things. a Diode, the High voltage capacitor or the Magnetron. The Diode is about $20 and the other two are @100 each. I hate to replace a high end mocrowave and spend what now is $500 if I can fix it myself. I will not call a repair person in. Trouble is apparently other than the diode, the other two items being high voltage related scare me. Of course I have no clue which of the three are bad and how to test them. Has anybody ever fixed a similar issue?