mstecha was being a bit blunt there... don't take offence - but essentially, what is implied, is that you really should know something about your job BEFORE you head into the industry.
This may mean spending some months doing amateur (hobbyist) electronics, reading books, surfing the net for anything you don't find or understand in the books, attempting your own projects, starting at a simple level, and gradually getting more complex.
Can you troubleshoot your own appliances? If not, do you think it's wise to start tinkering with other people's appliances?
Just some food for thought.