What were they? I assume one was the termination
switch.
Well, I'm home now and I realize that I was using a Panasonic
TR-120, not my Amdek (I wonder where that's buried?). The
only switch that makes a difference is labled:
Hi-Z
75 <ohm symbol>
It looks good in the "Hi-Z" position although I can now see
that if I turn up the brightness and contrast all the way I can
just make out the display in the 75ohm position. I've just
spent a couple of minutes fooling with the pot shaft sticking
out of the back panel and, sure enough, it makes a difference
in the behavior of the color regions that the color test program
displays. I'll try it on my "good" TV in a little while.