I don't think that college gives the same education that they used too. I was just given a bookshelf full of electronics and physics books from the 60's. Just opening one of those books makes a guy wonder how people learned all this stuff. They really dove deep into the hows and whys of electronics. My electronics courses that I had in college were basic. In fact I am thinking of starting my 6 year old off with my old text book and see how he does. It was really simple,"this is a diode, it looks like this.... it is basicly a one way valve" then I think there was about a half a paragraph on what made it work.
But to answer the topic question.... How do you guys know about all this.. technical stuff?
The simple answer is "The internet" When I first wanted to build a cnc machine in the late nineties. There wasn't nearly as much information as there is now. You really had to dig deep to find out what you didn't even know you needed to know. Now you can find anything you want to learn about pretty easy and there is probably a forum/usergroup to help you find more answers to stuff you didn't know you needed to know. The key here is that you have an interest in something and follow through with learning about it until something else catches your imagination. All I knew in the late nineties was that CNC machines were cool. I didn't know anything about stepper motors, servo motors, encoders motor drives or G-code. All I knew was that I could draw parts on a computer and I wanted to be able to make them(I went to school for mechanical drafting in the mid nineties, then back a few years ago for robotics) I will admit, I thought it was going to be easier than it was to build the first machine. But, I got it done and it worked, since then I have built around ten cnc machines, and have been able to put food on the table making stuff in my garage with them.
My latest interest is learning about welding. Sure, I can run mig, and I have done some tig and stick, heck I have even gas welded before. All out of neccessity. But now I want to seriously learn about it and become good at it. I am kind of leaning toward gas welding for the initial focus.