Welll I found at least one part that is causing my power supply mahem. I had tracked my problem down to the region on the output pin of U712A and determined that either U712, C609, R608, or VR604 was bad. The 15V rail is fine, so that made me think that U712 is likely good. C609 didn't seem like it was a likely candidate, since the voltage at pin 1 of U712 is low, not high. R608 would have been hot or noticeably cracked (when pushing on it with pencil eraser).. so I decided to pull the zener and test it with my PSU and a resistor. It doesn't start clipping until 48V, so there is the 5V that I am low on pin 1.
I noticed from some pics of a 468 main board from ebay that the CRT caps I have are not original. The only one that is in there and still original is the .0047uf 6kv, which I found an exact NOS replacement for for $4. However I'm sure that is not the main issue in the CRT circuit that is dragging down my 110V unreg.
I decided to map out what components get unusually warm, hot, and scalding on the main board, trigger, and vertical preamp. Mapping that out on the circuits is where I am now, but one thing I noticed is that Q530 is likely bad. It appears to have been replaced previously, also, since it is the 2n2484 and not the ST1046. When I touch the can, all hell breaks loose with the CRT. That transistor is right there smack in the first part of the CRT circuit at the 110V unreg feed, and the 5Vreg feeds into it also. So now I am going to put the bad zener back in so I can keep going until the replacement gets here, and check the voltages around Q530 to confirm. Fortunately enough, the voltage on all 3 pins is labeled on the schematic!
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As for the other issues... I noticed that quite a number of components get really hot in the Horizontal Amp circuit as well. I wish I had a 43V zener on hand to stick in there for now so I could figure out what issues that solves, and work on the ones that aren't caused by the bad waveforms that the zener issue caused. I'm thinking that fix will cool down all the bridge rectifiers and power supply rail components - and numerous other things, too.
I modified my UPS so that I can run my 465 off the battery, so now I can reference on stuff other than ground!!! YAAYYYY! That should help quite a bit!
I have a decent list of parts to get, and some I already ordered (109D's, 30D's, 500D's, Z5U ceramics..). So far my list contains solid tantalums, some of the common diodes, zeners, 2n5551's... does anyone have any suggestions for spare parts I should have on hand for this scope and whatever one I end up with next?