[sdiy] Bi-Color LED Question

[Ken Elhardt]

I hooked up a bi-colored LED (red/green) I bought years ago to try it
out and I'm curious about something.  I can get the green portion to
light, and the red, but not at the same time.  If I have power applied
to the green and then hook power to the red, it shuts off the green as
if the red has priority over the green so I can't get yellow out of
the thing.  Is this how all bi-colored LED's work?

Thanks for any info,
-Elhardt