That looks suspiciously like the one I had with exactly the same fault. Turned out to be the transformer had gone faulty. If you can get the power supply out, it's easy to change the transformer and they are easily available. I used one like this. You might find the equivalent cheaper elsewhere but I tend to use Rapid as being fairly quick and reliable. Without being able to test the power supply, I am guessing somewhat at the problem but it's the most likely to blow the fuse immediately. I've found my original order, and it looks as if I fitted mine about 6 years ago and it's been running fine ever since.

A complication might be that the original power supply also has a 5V winding that may or not be used in your machine. It might be difficult to source an exact replacement transformer (unless someone knows better?) In my case, I didn't need to use it as I had a separate 5V supply but you need to check. Photos of the power supply and its connections would help. Worst case, a separate 5V power supply is easily available for under a tenner.

If you can supply any additional info - like some clear pictures - then I or probably a number of others on this site would be happy to guide you through the next steps. I suspect that electronics might not be your strong point, which very much puts you in the majority around here! Don't worry - help will arrive. You should be able to fix this quickly and for a lot less than a identical replacement - if you could find one...