Find all your DIY electronics in the MakerShed. 3D Printing, Kits, Arduino, Raspberry Pi, Books & more!

Make: television presents:

  • Sunlight Poem – Ji Yeon Song’s one-day poem projector made of cardboard and sunlight.
  • Pedal-Powered Blender – David Butcher outfits a bike with a generator that can run a blender.
  • Handmade Theremin- Lorin Parker’s theremin works great and sounds even better.
  • Time-lapse Camera – Jay Burlage hacks into a clock to create an inexpensive way of taking panning time-lapse photography. Watch more of Jay’s videos at his YouTube channel.
  • [Trouble Maker] Cellphone Jammer – Limor Fried made a handheld RF emitter that can disrupts cellphone signals. Never overhear awkward conversations again!

    Submit a video of your own project at makerchannel.org.

    Get the m4v, subscribe in iTunes, watch on YouTube or Blip.


    Related
  • Comments

    1. trevyn says:

      I’m all for extra-complex systems to do things like power blenders, but I have to say that the conversion from mechanical power->12VDC->120VAC->mechanical power isn’t very efficient. What you really need is a direct mechanical drive:

      http://store.xtracycle.com/_e/Bicycle_Powered_Blenders/product/B3-0100-/B3_Xtra_Stationary_Setup.htm

    2. Webster says:

      This might seem like a picky negative thing but someone with bad intentions could use the cell phone blocker to, say, interrupt a 911 call for example. an attacker could use it to stifle a call for help perhaps??

      ah but these ares small annoyances compared to being subjected to someone else’s conversations.

      Just an observation.

      I know, creating the bomb doesn’t kill anyone.

    3. Lead Dreamer says:

      I assume you pulled the cellphone jammer ’cause it’s outright illegal and could lead to significant federal fines and imprisonment? I’m all for hacking, but even a *tiny* bit of research is in order – you wouldn’t send someone out with an organic chemistry set without the basics; you wouldn’t have them play with potassium nitrates without basic research – and bluntly, anyone who could use the spectrum analyzer knows better.

      1. Make: television says:

        Hi Lead Dreamer,

        Actually the video is still up, you just have to watch to the end. The Maker in this video, Limor Fried, is an accomplished engineer with a strong background in electronics. Feel free to visit http://www.ladyada.net/make/wavebubble/ for more information, there she addresses the legality of this project along with a disclaimer about the difficulty level. We hope that projects like this are inspiring, challenging and thought provoking. We don’t condone any illegal activity, but we we’re all for challenging status quo with subversion.

        Thank you for your comment!

    4. Curmudgeon says:

      What responsibility do you as the publisher of the information have regarding potential misuse of the information?

      The problem is, this is not just a benign use of technology to stimulate social discourse and challenge the status quo by subversion as you suggest. This is a potentially dangerous weapon that could be used by, say, a stalker for example.

      Is the technology cool? Sure. Does the artist/engineer deserve congratulations for her accomplishment. absolutely. However The technology doesn’t exist in a vacuum and the issue of legality aside, Where does her responsibility to the community at large and your responsibility as a publisher lie?

      Congratulations to the artist, she has provoked a discussion not only of the role and place of technology in our lives but the responsibility of the artist and journalist in public discourse.

    5. walternator says:

      Hi Limor Fried
      I was wandering if you could send me some instructions or something on how to make the cellphone jammer because i’m constantly having the same trouble as you when i catch the bus every morning.
      Thanks
      Walternator

    6. walternator says:

      might help if i tell you my e-mail
      mr.walter@ntlworld.com
      cheers

    7. walternator says:

      i didn’t read the website link that you left so there’s no need to tell me the specs
      walternator

    8. Anonymous says:

      Limor Fried, can’t you put your skills to work doing something positive for the world, rather than interupting someone else’s life? Did it ever occur to you that you might be interupting an urgent or emmergency phone call! I hope you have a good attorney.

    9. No Phones Please says:

      Illegal? Dangerous? Irresponsible?

      Operating a motor vehicle while using a cel phone is all of these and more. It is negligent and homicidal. As a victim of a cel phone using driver who totaled out my car, I know this to be a fact.

      Cel phone jammers should be required installed in all new motor vehicles and required to be retrofitted into all existing motor vehicles, to go on with the ignition switch, to prevent driver’s from talking on their phones instead of paying attention to the road.

      Anyone complaining about cel phone jammers is more interested in continuing their dangerous behavior than the safety of themselves and those they will inevitably injure in the car accidents they cause.

      Kudos to Makezine!

      1. Freax says:

        a) what has this to do with people don’t wanting everybody to know how to build a jammer?
        b)
        So I am not allowed to ask someone else in the car to phone somebody to ask for the way/to announce that we are late/whatever?
        So that I can’t use my phone to call for help after an accident, because I am stuck in the car and the dumb jammer survived?

        Sorry, but this is like forbidding transport of tools in public, because you can kill somebody with a hammer or a chainsaw… except that phone is a much more useful item on street.

      2. OLLIE OLIVEIRA says:

        Love it and would buy 1 today since making one is not posable
        age and 10 thumbs

    10. Jeff says:

      Funny how no one mentioned how jammers are being used to prevent IED’s from exploding in Iraq.

      -Iraq Veteran

    11. raydust says:

      cellphone jammers are on the market, in japan, where theatres use them. Here in the USA, those frequencies are used by emergency and police operations. while Jammers DO HAVE PURPOSES in the RIGHT HANDS, like the military, its a matter of in whose hands they are. its like a hammer, one person would build a house, another repairs the dog house and a deranged person uses it to bludgeoon to death their relatives while asleep. its not the hammer, its the USER. Whatever school Limor Fried went to obviously never taught responsiblity nor respect for law. the FCC would fine and jail her, then fine createTV for the broadcast if not shit them down. back in the 1900′s rf students created “spark gap generators” that blasted RF across the spectrum, creating a similiar effect, so its not a new technique by any stretch of the imagination.

    12. Ryan Moore says:

      That is a nice example of a portable rf jammer those could be good for law enforcement and military who need a lightweight discreet radio jamming device.

    13. nn nerrisa says:

      Thank you for this posting, you’ve got a few solid points but will you be posting a follow up to this?
      ——–cell phone jammer http://www.espow.com/jammers/security-surveillance-jammer.html