I've been watching oscilloscopes on ebay for a few weeks now. I'd like to get one to learn with, but also one that will do most of what I will ever want to do with one. What are some applications of 2 or more channels? I doubt I will need this at first, but everyone seems to recommend it. What about if I wanted to look at 3 phase mains or the output of a 3 phase generator or roto-phase? With 3 or 4 channels could look at all 3 phases and see if they were all uniform? Would they appear seperatly on the screen or can they be super imposed on top of eachother? Or would there be no reason to ever do this?