Beaten by VT100 PSU.

[tony duell]

>
> > More load _reduces_ the ripple? That's very unusual.
> 
> Perhaps a parasitic oscillation that's defeated by more load
> because now the loop gain is below 1?

But loading the +5V output also reduces the ripple on the +12V
output. Loading the +5V output would, I think, vary the mark-space
ratio of the drive to the main chopper and thus the drive signal to
the 555 in the +12V regulator. Not that I can see how that would
affect things.

-tony