That's what I tried too, as well as buy a text book. (except for the age part)
But I don't have the time nor interest to work on it anymore to get to the level where I could analyze and understand the circuit diagram of a typical amplifier, I'd need an estimated 100 hours of studying; approximately the time spent on one course in university.
Which is exactly what I'm doing right now. Practical electrical engineering is, thankfully, different to the electromagnetic theory I used to do.