Let’s start by giving the author’s channel :
Here’s a presentation from Dave Jones of the manufacturing process of an electronic device. I found these three videos really interesting. It’s a thing that we don’t see often and didn’t really think about.
there’s also this power supply design :
I highly recommend to electronic aficionados to go visit his (largely big) youtube channel. There’s a massive content ! Lot a cool stuff in it : teardown , electronic lesson , thoughts about electronic world ect…