Broken oscope. suggestions on what to check?

Hi All,

My broken oscope just arrived and I'm trying to figure out what needs to be replaced. Looks like it is out of focus. Hopefully it doent have any other problems, but I guess i'll find out once I get the display fixed.

Any idea where to start? I'm thinking it might be something with the high voltage board? I have another dead 2430A that I could swap with, but the board layouts are different. So I'm not sure if they are interchangable?

There is a CD with the service manual listed on eBay.
**broken link removed**

Yeouch! Looks nasty.

The vert timebase is oscillating, maybe the horiz too, and there is a very obvious lower freq noise component shown by the darker areas...

I bet it's got bad caps in the PSU and the PSU rails look more like AC.