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July 26, 2006 AT 1:16 pm

Cigarette pack cellphone jammer

At HOPE I got to look at a cell-phone jammer owned by a friend. This one is interesting because 1) its extremely well designed 2) it’s very small and 3) it actually has a PLL instead of just being open-loop controlled. The entire package fits into a pack of cigarettes.

(For more disassembly photos & comments…)

The design is made of 3 PCBs bolted together.

The silkscreened cover is also the microstripline antenna for the two VCOs


The battery is a large LiIon, there’s a protection circuit that looks like it was removed from something else and soldered on. And a somewhat questionable LM317 charger. I’d only trust a 317 for a lead acid, but I guess if you’ve got a protection circuit the worst is just that you’ll reduce the battery life

I didn’t get too much time with it so I just took photos of the disassembly. Looks like there’s some boost converters, 2 PLLs (16-TSSOP parts), a micro to control them, and the VCOs. A very nice design! And I like the idea fitting it into a cigarette pack.

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5 Comments

  1. Hello!
    It’s funny kit.
    I want a make this Kit, But I don’t know how to buy or get a kit..
    Please tell me how to make or buy.

  2. This is very cool, and I’m even interested in making the thing (even with the SMT soldering required! it would give me good practice)

    however, the concept of having it fit in a cigarette pack: I just want to warn (as I’m sure you know) that since this doesn’t even attempt o meet FCC safety guidelines (in fact, it’s designed to break FCC RF guidelines!) I’d NEVER put this in my pocket running. It is cool that you could have an innocuous altoid tin sitting in the seat next to you in the movie theater or on the counter at your favourite restaurant, but I’d just like to caution against putting unregulated, high-power RF devices right next to your reproductive organs! (paranoia? who knows!)

    anyway, nice stuff.

  3. Cool, but I think this type is better – it has no long rubber antenna and looks like a mobile: http://www.techgadgetz.com/cjama.htm – it seems to be the smallest and most realistic one ive seen yet.

  4. LambdaUmoja, if you’re going to advertise your products here you should at least spam the right post! This jammer doesn’t have external antennas! ;)

  5. Hi everyone,

    Curious,

    I am a member of a Tactical paintball team in Ontario Canada and would like an RF Jammer that would block the signals from a basic hand held radio or throat mic.

    Any suggestions LadyADA?..anyone?

    Looking forward to hearing from you,

    Darren

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