Pulled my 475 out of the storage shed cause I got a new table/space that I want to set up as a tinkering center. It was working the last time I turned it on a couple years ago. Now I have no trace, beam finder shows nothing, trigger ready light doesn't come on. I googled and found the troubleshooting guide (general to tek scopes) and the navy's service manual for it. I got the cover off and the navy manual showed where to test the power supply's outputs. The +110V, +50V, and +5V are good. The +15V, -15V, and -8V are bad. I started trying to track down the problem by starting with the +15V supply. The navy manual shows it as one regulator with Q1444, Q1446, and Q1448 on it, and a feedback amp U1454A. I found it on the board, but the Q1444, Q1446, and Q1448 are discrete components (three legged, small silver cylinders) and the feedback amp is a 8 legged chip (op amp, I'm guessing). The unregulated 15V feed was going into pin 1 of the op amp, and pin 2 had the same 116mV that was on the +15V test pin across the board, so I'm guessing that's the output.
I stupidly pulled out Q1444 while it was on, and I had a cap pop and the fuse blow, so I have to run up to Radio Shack. I figured I might solicit some opinions on what the root cause of the problem might be, before I spend any more time monkeying around.
I don't have a multimeter that goes over 600V, so I can't check the 2450V high voltage test point.