I have the same problem after 18mths light use, currently sat here with the thing in pieces and I've just located the fuse in question. It's housed in a black plastic case at the bottom and connects the big transformer to the capacitor on a red lead, inside is a glass fuse rated 5KV 0.8A. Off to maplins for a replacement, will let you know if the next one pops or lasts.
Chris belling mender the 2nd, December 2010