When I went to school for electronics (in the late 80s), we learned how computers worked and how to troubleshoot them on a donated PDP 11/70… or was it an 11/40… It was interesting to have to peruse blueprints of circuitry that were published when I was only a toddler. Typically our instructor would ‘break’ some function of the machine by plugging in a faulty chip or cutting a wire, and we would have to trace down where the problem lay by putting an oscilloscope on the right pins of the wire-wrapped backplane, containing thousands of connections, after studying the blueprints to find it, then locate the problem on one of the hundreds of plug-in boards and fix it. (The processor alone was a couple dozen boards as I recall) If I could have gone back in time, I probably could have made a decent living just repairing these beasts after that course. For my final project, I recall interfacing a Radio Shack speech synthesizer chip with this machine and writing software to make it work–toggling the program into the machine in octal with the front panel switches.
Fascinating to think that my smart phone has more computing power than this thing had, back in the day.
But yes, I get attached to electronics gear too.