I picked up a Tek 492p that's about the same vintage as I am, and it seems to have some issues. I'm getting intermittent 'Error 60' messages, the trace seems to have a discontinuity it will either stop drawing halfway across the display (the peak/avg trace continues to make it) or there's a 2 or 3 division drop on the vertical scale depending on the setting I'm in.
The physical display is nice, with a strong beam, and the overall fit & finish is quite good. Opt 1, 2, and 3 are loaded.
I've pulled down the user manual as well as both service manuals and will be reading them tonight. The plan of attack is to pop the case this weekend, check the voltages, check all of the tantalum caps, then the rigid coax connections. 300 odd pages of replaceable parts sounds like fun.
This is my first spectrum analyzer so I don't really have any idea what I'm doing. Any traps for young players I should watch out for?