My house was built in 1982. When I bought it in 1995 it had a GE Spacemaker microwave oven. It has been working without problems - until this morning. As I was about to set the cook time I noticed the display was black. In the past it showed the time. I pressed a couple of buttons but the display remained black. I unplugged the oven and put in my receptacle tester. It told me that the hot and the neutral were reversed, so I switched them to where they were supposed to be, plugged the oven back in, and Voila! The display came on! So how is it that the oven worked at least for 24 years (and probably worked since 1982) with those wires reversed and then suddenly stopped working???