"Setterm" and "xset s off" are neat, but they did not do the
trick for me.
Instead, I had to edit my /etc/X11/xorg.conf (was XF86Config-4).
Section "Monitor"
Identifier "alans_monitor"
HorizSync 30-64
VertRefresh 50-130
# Option "DPMS" <-- comment this out
EndSection
Thanks for all of the suggestions!
Alan