Sunbeam SMW5500 micro/convection oven shorted out...

Question

When using microwave I felt something like a buzzing while pressing the button to open door. A fuse blew in main wall panel. Replaced blown fuse and micro worked a bit more and then same thing happened while pressing button to open door. This time micro is DEAD - not even a light working. My computer is on same circuit and is back up and running. I've been reading a number of other problems and solutions that seem similar and I wonder if there is a fuse in this model as well. Dunno if I should invest in repair or just buy new one. Won't be able to afford another combo with convection if I buy new so would rather get this one fixed if possible. Thanks in advance to all you fantastic techs that are willing to offer advice.