So let me tell you a tale of graciousness, skill, craftsmanship and intelligence:
It wasn't enough that work sucked and that university bored me to tears today, not even damaging my scope by putting in the new fan backwards was enough... no... after coming home, I started to repair my 'scope.
First I sucked the orange thing, that I assumed to be a resistor out only to notice that it in fact was a capacitor. The resistor in question was the blue device next to it (R52) clearly marked 6R20. I measured it and it showed 330 ohm instead of 6.2. So I tried to suck that out. In the process, I lifted both pads without any usable traces left to use as makeshift pads. Wonderful.
So I bodged in 4 parallel 27 ohm half-watt axial resistors (the 1W rating for the original one was a bit low for my taste with a 12V, 200mA fan) between C46 and the 15V rail directly at the main connector. The fan worked now. Yay.
I put the scope back together, turned it on and... nothing except the main grid, no status, no controls, no signal... Terrific.
I disassembled it again and found, that I broke a bodge wire at on of the ICs. I fixed that with a new wire, checked if it basically worked and put it back together. Finally! Or so I thought...
As soon as I turned it on, I let the smoke of of the resistors I put in earlier. Not sure how but I must have shorted something out. Super... Perfect...
At least the scope itself seems to be undamaged.
I started to take it apart again for a third time and while taking off the front panel I broke off one of the knobs I fixed two days ago. Why... just why?!
It's 10:30pm here and I think, I'm going to bed now.