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Build Your Own Stun Gun
mariox19 writes "Wondering what to do with your disposable camera when you're finished with it? TechTV has an article describing how to reach out and zap someone with a home-made stun gun. I discovered the link via Bruce Schneier's latest Cryptogram, where Schneier half-jokingly warns not to let airport security find out about this, lest (in their 'wisdom') they ban cameras along with nail clippers."
However, when I was leaving Japan I noticed security at Haneda had no such rules. In fact, you could buy both alkaline and lithium batteries at the shops beyond the security checkpoint there.
I've yet to get an explanation for why plain batteries are considered a security risk.
Actually, if you can have any kind of discharge, you can build a primitive coil gun/sten gun.
:)
;)
In my freshman year of EE, we used to build capacitor banks and use them to power our coil guns.
And another thing to do is to use Flyback drivers to discharge and use them to power hi-voltage stuff. Ofcourse, this knowledge came to us much later, but was useful neverthless
With a little bit of expertise, you can build a transistor flyback driver in a matter of minutes and do quite a lot of nasty things with it
I've gotten whacked with charged flash caps a number of times. It's about enough power to make you jump a bit and shake your hand.
The article talks about "holding it on someone for 5 seconds" - well, that won't do a damn thing; this is a capacitor, it discharges and that's it. There's a charging circuit, but it's very wimpy; it takes the circuit 5 to 10 seconds to put that much energy into a cap for a few millisecond shock.
You want a deterrent? Learn to run fast. You're going to need it, ESPECIALLY if you try to use one of these things.
After watching a video where they take apart a MuVo2 for its Hitachi Microdrive and then say the iPod mini has the same drive (correct, but the iPod's microdrive will NOT work in any digital cameras), I'm convinced TechTV's "dark tips" have become dangerously innacurate.
Don't do this. Compared to a stun gun, a photoflash capacitor stores a lower voltage, direct current high amperage charge which is delivered all at once. Yes, if delivered across the heart, it could be leathal. If delivered across flesh, it will burn you. In almost no cases will it stun you other than the surprise of getting shocked.
Real stun guns use a high frequency alternating current, VERY low amperage spark. Real stun guns are also quite cheap on eBay.
If you want to make a joke shocker from a disposable camera flash, here's a much safer method:
Get a cheap disposable camera and take it apart. Discharge the capacitor with a screwdriver. Get rid of the capacitor.
Notice the heavily insulated wire running to the center of the xenon photoflash bulb? Remove it from the photoflash bulb and attach a longer wire that will go to one of you're "shocker's" probes. Make sure the connection is well insulated.
Locate the portion of the circuit board that is shorted to activate the flash charging circuit. Usually, it's a small flexible metal "button" with plastic over it. Yank that sucker off of there and short the points on the board out with solder, or if you like, you can attach wires and add your own on/off switch.
Get a battery holder, some sort of case to put all this in, and a momentary pushbutton switch. Attach the wires from the battery holder to the circuit board, a wire from Negative to your other "shocker probe". Connect the momentary pushbutton switch to the trigger circuit (usually two peices of metal that were positioned near the shutter). Position the probes to be less than 1/8" apart. Put all this crap in a box and try it out. When you press the momentary pushbutton switch, you should get a nice spark.
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DRM is like antifreeze, to the MPAA/RIAA it's sweet, to the consumers it's poison.
Yes, it did hurt.