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James writes in with this fun project he made to help him find his tent at a festival. I like the way he interfaced his indicator beacon to the cell phone. When the phone gets an incoming call, it lights up the screen, so he mounted a photoresistor right next to it. This allowed him to build a very simple analog circuit to control the whole thing. Nice hack!

If you used a pay-as-you phone for this, and hung up after a couple rings, it seems like this could be a really economical way to go.

This is what the completed project looks like:


  • James

    Dave: I like you bubble machine looks fun – it was nice it was done on tinker workshop i haven’t been on there toy hacking but went on the arduino workshop which was great

    Huh ?: it did cross my mind that i shouldn’t publish this as it may inspire the wrong type of people but this is really a basic setup and most school kids that have study physics could cum up with something similar.

    Coe: Thanks for you comments and i agree

  • Dave Chatting

    This is great and a nice write-up too

    Some friends and I built the “Telebubble Machine” along similar lines, at the Toy Hacking Workshop in London

    It’s great how super simple sensors can detect complex things in the right context


    • Matt Mets

      Ooo, thanks for sharing! The bubble machine looks like a really fun project.

  • huh?

    why don’t you just show someone how to make a detonator?

    • Coe

      This is far too unreliable for a det trigger. Besides, anybody in the business of making such things already knows how.

      This type of knee-jerk reaction is what keeps innovation at bay. If you continue to think like this, then you might as well lie down and give up, because nothing is “safe”. One of the best hand-to-hand combat weapons is thick rolled-up magazine. Should we get rid of those too???

      • Anonymous

        No! you can’t take my Make magazine away.

        Use the Edmunds catalog…

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