I have a home theater, with a projector, and a retractable screen.
Up until recently, I have had to use three remotes, minimum, to control my setup. I got tired of this, so I put together this little gizmo to allow me to control my (trigger in-less) projector with a trigger signal.

My requirements in order of importance:

  • Parasitically powered from trigger signal
  • Minimum parts count
  • maximum reuse of existing parts bin contents

I got 2/3, as I ordered a small buck regulator for an initial breadboard revision.