Many years ago I built a small electronic puzzle box with instructions from a magic publication.
The box had one light and three switches (push on/push off).
The magician was the only one able to turn the light on.
Does anyone remember where I read this?
I'm thinking MAGIC or Linking Ring, but can't find it when I look.
Thanks.

I've seen similar, but not that specific circuit. Here are some links that might help.

on the logic:

http://www.maa.org/mathland/mathtrek_01_09_06.html
http://plus.maths.org/content/os/issue36......ma/index <- scroll to the bottom, might be the wiring diagram you're looking for

similar projects:

http://www.diy-electronic-projects.com/p305-Magic-Wand-Conjuring-Trick-
http://makeprojects.com/Project/Mystery+......es/988/1

Still looking, eh Joe? ;-)

http://www.themagiccafe.com/forums/viewt......forum=26

I still don't know, either. Based on when I built mine (late 1990's) it was probably not in the LINKING RING because I was not an IBM member yet. I was only subscribed to MAGIC and GENII at the time, so maybe it's in one of those. Then again, there's also a chance I saw it in some magazine compendium, because I had just discovered L&L around that time and was buying Pallbearer's Review, Epilogue, and The Chronicles... (I'd look these up but my books are in storage right now in preparation for a move.)

I've had a lot of fun with this simple trick. I've shown it to engineers, and they usually come up with the most convoluted, complicated explanation for how it works. I showed it to one electronics engineer, and I thought for sure he'd immediately see right through it. Nope!

- Ross