Microwave Oven Problem

I think our microwave is on the way out but I am not too sure as to what could be responsible.

It only cost around £100 when purchased just over 18 months ago but it has been working without any problems, apart from a replacement bulb, until today.

I noticed that the display was not illuminated so I changed the fuse in the plug and when that did not work I replaced the time delay fuse on the board inside the machine.

After doing this and plugging the oven back in nothing happened, apart from tripping the main switch on the fuse box and blowing the time delay fuse inside the machine.

There was no visible sign of a problem.

Any ideas on what could possibly be causing the problem would be much appreciated!

There are four major components in a microwave oven, any one of these failing could give a sympton you have on yours, going short circuit and blowing the fuse. The major components are a large step up mains transformer a heavy current rectifier a very large electrolytic capacitor and a magnetron which creates the micro waves. These components generate huge voltages and capable of drawing high currents from these parts even after being switched off for some time. It is for this reason the diy'er is not advised to attempt repairs with these items. Also by safety regulations after dismantling a leakage tests must be done as a matter of course on the appliance and cannot be done without the use of a quite sophisticated leakage test meter which generally is not available to the layman.
Hope this has been of some help