Failed in the middle of a measurement last night - no display, no power
LED, a few red LEDs on the front panel come on intermittently at
power-up. The familiar burnt smell coming from the back, but no smoke.
The enclosure felt a a bit hotter than usual immediately afterwards.

The incandescents on the graticule working fine though, and they're fed
off the negative PSU rail, but the positive low-voltage supply is
definitely down for the count. I haven't had a chance to open it up yet
but hoping it's an easy fix...