Build Your Own Stun Gun 311
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."
Stun Gun in a Camera... (Score:5, Funny)
I can see the FARK now (Score:5, Funny)
No electricals on the testicles, please (Score:3, Funny)
If you added bluetooth to the mix, you could download the image to your desktop instantly so it it becomes your next screensaver or desktop background. I'm sure the Abu Ghraib guys will love to hear their whole interrogation pipeline can be reduced to a single step.
Wow (Score:3, Interesting)
Re:Wow (Score:5, Insightful)
I don't know any way they'd be able to regulate those situations, since capacitors of some type are found in nearly every electronic device. Anything that has to have a "flash" of power has a high-voltage capacitor behind it... the cammera flashbulb being the most typical example.
Re:Wow (Score:4, Insightful)
Re:Wow (Score:5, Funny)
Re:Wow (Score:2)
Yes, just take a neon bulb power supply and one of those magic voltage multipliers from an old TV...mmmm, I love the smell of ozone in the morning.
Re:Wow (Score:2, Funny)
Re:Wow (Score:4, Interesting)
The disposable camera route seems kind of silly. Most people who would attempt this should have enough parts laying around their house to build one. I believe an old PC power supply would have the required components, or it should only cost a couple bucks at Radio Shack to build one.
I like your softball idea, but it would seem to pose too much of a chance of not hitting the electrodes correctly. There's so much chance they'd catch the ball wrong, and both electrodes would hit one hand and they'd only say "Ow!" before beating the crap out of you.
Re:Wow (Score:2)
I also had a dis
Re: (Score:2)
Re:Wow (Score:3, Interesting)
Just to be irritatingly picky, I'm going to point out that there's a difference between a taser and a stun gun.
"Taser" is actually an acronym for "Thomas A. Smith Electric Rifle," and is a handheld weapon which fires barbs into its target with compressed air. The barbs are tethered to the gun with wires which transmit the electricity.
A stun "gun" is a handheld device that has two short metal probs that you physically touch to the target, lik
Hmmm (Score:5, Funny)
Re:Hmmm (Score:2)
All battery devices? (Score:2)
This could be tolerated if some sort of PC functionality were included in seatback entertainment consoles, but since those aren't even found on every plane, I'm going to guess that this would be hell for geek air travelers.
Re:All battery devices? Laptop Display Inverters (Score:3, Informative)
Yep, some backlight inverters for laptops run at over 1000V for firing a cold cathode tube.
Re:All battery devices? (Score:5, Insightful)
Way back... (Score:5, Funny)
In junior high electronic shop class (~1978-79) we'd charge a capacitor up, say "Hey $NAME.." and toss it to the person. Force of habit dictated the person would usually catch it and get a nice suprise.
Re:Way back... (Score:5, Funny)
The trick was not to touch the metal and keep it in another non-covered cup.
Re:Way back... (Score:5, Interesting)
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
Actually, if you can have any kind of discharge... (Score:5, Funny)
pr0n book (Score:2, Funny)
wonder if he still has that thing.....
Re:Way back... (Score:5, Funny)
We had it even simpler in NYC public school. We'd shout someone's name, and when they turned around we'd shoot them. Good times.
Re:Way back... (Score:3, Funny)
Re:Way back... (Score:2)
Re:Way back... (Score:2)
Re:Way back... (Score:4, Interesting)
Yes, it did hurt.
Re:Way back... (Score:2)
But if you really want to get hurt, stick your hand up any high-voltage EM generator. I've had really bad RF burn marks from my EM lab from these things.
Or, try getting near a Tesla coil wearing wool
Could they get banned at airports? (Score:5, Interesting)
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.
Re:Could they get banned at airports? (Score:5, Interesting)
I think you just got it. Batteries represent stored electicity... and they can't exactly trust that the battery's voltage is really what's on the label if you don't have a device that you can show properly operates.
Sure, that's paranoid... but that's what the security people are in the business of doing.
Re:Could they get banned at airports? (Score:5, Funny)
Re:Could they get banned at airports? (Score:2)
You'll also have pretty much eliminated the Terror potential since the plane can't be used as a weapon anymore and there are no hostages.
Re:Could they get banned at airports? (Score:3, Informative)
Re:Could they get banned at airports? (Score:2)
Re:Could they get banned at airports? (Score:5, Insightful)
> seemingly innocent objects.
It's clear, then. We must immediately ban all seemingly innocent objects.
Idiots.
Re:Could they get banned at airports? (Score:3, Insightful)
Maybe extend the observation phase to birth.
Re:Could they get banned at airports? (Score:2)
Isn't that in the current plan?
Re:Could they get banned at airports? (Score:3, Insightful)
Re:Could they get banned at airports? (Score:2)
Force me to send my laptop through a scanner separately. (Or sometimes, not)
Force me to boot my laptop. (Or sometimes, not)
Force me to take off my shoes which have metal in them. (Or sometimes, not)
Pad me down. (Or sometimes, not)
Confiscate my keychain can opener. (Went on several flights before they took it away)
Check my luggage. (Or someti
Re:Could they get banned at airports? (Score:2)
Great.. (Score:2, Funny)
Only weak in the knees (Score:2)
Re:Only weak in the knees (Score:4, Insightful)
Re:Only weak in the knees (Score:2, Informative)
The goal is not to inflict pain, that would not even stop a determined attacker, and he would end up hurting twice as bad for pissing him off.
The point is not to shock a person's heart with high voltage. The way real police grade tasers work is by sending electric pulse into the muscles, so the muscles contract and retract multiple times per second (or is it milisec
Anything new? (Score:2)
The following Kill Bill-esque encounters with sworn playground enemies was a thrill. In fact, that's about when I got some respect for the first time from the 'in crew'.
Don't think this is going to work to well... (Score:5, Informative)
Re:Don't think this is going to work to well... (Score:2)
Tim
Where's the love? (Score:5, Funny)
Re:Where's the love? (Score:3, Informative)
http://www.techtv.com/unscrewed/ihateyou/archiv
Cattle Prod (Score:5, Informative)
Re:Cattle Prod (Score:2)
Sheesh!
It's called a capacitor :-) (Score:2, Informative)
This is dangerous (Score:5, Informative)
But beware that this is really dangerous. I touched a flash capacitor some time ago, 40uF@400V are not really nice. 200uF@600V and I can assure you that you will fly across the room, hopefully surviving the shock. I have several 1uF@10kV caps, and I don'T dare to charge them to > 3kV (LOUD, risk of EMI, some PC failures already because of cap discharges)
Because this is all too destructive, here is a nice modification (I TAKE NO RESPONSIBILITY!!):
Leave the connection to the flash tube intact. Increase the capacity of the HV cap. Add capacitors salvaged from other cameras, or as a very cheap alternative, from PC power supplies.
Check the voltage rating. Often, they're rated at 800uF@200V, if your flash light operates around 200V, connect two of them in series (+ -)(+ -).
You can get nice, very *bright* flashes with this method. Do not add to much or the flash time will explode.
Problems here:
- NEVER touch power supply caps, they can store 10x - 20x the energy of flash caps. Lethal!
- Discharge the CAPs from the power supplies before salvaging.
- Discharge the unit after use with an *isolated* gripper, better yet, a high-wattage resistor (few kOhms) hold by an *isolated* gripper.
Someone said that more that more than 10 joule are dangerous, but I think you should not set an upper bound for harmless capacitors.
PS. Someone told me that you have to drink much liquid after an electric shock. Because it removes toxic products from your body which could result in kidney failure or so. Maybe the medicine-studying
But... better don't let this happen!
Re:This is dangerous (Score:5, Informative)
Yeah, not a bright (so to speak) idea. When a significant jolt of electricity runs through your body, it can cause destruction of lots of cells (including those that do important things like regulate heart rhythm). When the cells get fried, the explode. If they're muscle cells (and you have lots of them even if you're a ninety pound weakling), they spill a protein call myoglobin. Too much myoglobin clogs up your kidneys. This isn't a desirable outcome. Since "the solution to pollution is dilution", pushing lots of fluids can help protect the kidneys. This is typical care for an burn patient (electric or otherwise) in a hospital setting. As the old saying goes, "do not try this at home..."
Re:This is dangerous (Score:2)
A friend of mine who is in the Special Forces told me that when they were in the desert his friend got bitten by a very deadly snake. Were it not for the DC shock they gave him from a nearby car's battery, he would have died. He said that it works because the muscle contraction that results restricts the movement of the venom. Furthermore, the lactic acid produced as a byproduct of the extreme muscle contraction works to destr
Re:This is dangerous (Score:4, Funny)
Re:This is dangerous (Score:4, Interesting)
- NEVER touch power supply caps, they can store 10x - 20x the energy of flash caps. Lethal!
- Discharge the CAPs from the power supplies before salvaging.
- Discharge the unit after use with an *isolated* gripper, better yet, a high-wattage resistor (few kOhms) hold by an *isolated* gripper.
I deal with high voltage power caps in my hobbies of railgun and coilgun design. Whenever building a prototype, I know I'm going to be monkeying around with it, and I know I'm going to get shocked accidentally...
So I take a high ohm resistor and put it across the cap leads. Put it as close to the cap as possible; if it's after you in the circuit, the high frequency nature of the cap discharge can cause it to not affect the circuit.
How big? Well the resistor here is serving two purposes; one as a bleed resistor. In that case, you want it's rating high enough that it doesn't put a strain on your charging circuitry, but still low enough to bleed power relatively quickly. From that standpoint something between about 10 KOhm and 1 MOhm should be good; caps don't have a ton of storage capacity so even a high value resistor can bleed voltage relatively quickly. And 50V, while impressive, just isn't as dangerous as 1000V... Batteries usually have an internal resistance of about 80 Ohms (the battery appears to resist the flow of electricity like an 80 Ohm resistor would, when it is in short circuit)... depending on the efficiency and design of the charging circuit, low resistances might significantly affect its performance.
Of course the other side of the equation is that the resistor is the last line of safety in case of accidental short circuit during charging; during a short circuit, the resistor will absorb some portion of the power. My trusty voltmeter says that my resistance from terminal to terminal (that is, one hand to the other) is above 1 MOhm when lightly touching the terminals, and hovers near 47 KOhm when I am.
I'd like the bleed resistor to be significantly more conductive than I am; if it's before me in the circuit and I'm lucky enough, it might save my life... I usually choose about 10 KOhm.
Oh and I'm experimenting with putting it in series with an open-core inductor. From a power perspective, an open-core inductor is a magnetic energy storage device. And for fast spikes, an inductor ends up having far more energy storage than a capacitor. By having it parallel to the capacitor but series with a large resistance, I shouldn't affect the discharge time total as I would with an inductor in series with the cap. The inductor shouldn't affect the circuit inductance enough to matter (typical circuit inductance in a coilgun might be 100-2000 mH)
But that's all beside the point. The point is: bleed resistors don't have to be held in place. For maximum safety, make them permanent...
Of course, that's assuming that your charging circuit will provide charge constantly, and isn't on some sort of timer or level sensor...
Re:This is dangerous (Score:2)
Awe Man! (Score:3, Insightful)
Re:Awe Man! (Score:5, Funny)
Figures! (Score:2)
Re:Awe Man! (Score:2)
Slashdotting airport security (Score:2, Funny)
Posting it on Slashdot ought to keep it a secret!
er, wait...
--Ben
pixelchef.net [pixelchef.net]
capcaitors aren't full... (Score:4, Interesting)
Re:capcaitors aren't full... (Score:3, Funny)
Re:capcaitors aren't full... (Score:2)
The sound was equivalent to a small gun going off. It more than startled everyone in my apartment =)
No...don't...just don't...... (Score:5, Funny)
NOT a problem (Score:5, Interesting)
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.
Re:NOT a problem (Score:2)
You want a deterrent? Learn to run fast. You're going to need it, ESPECIALLY if you try to use one of these things.
Yeah I was thinking the same thing reading that comment...
Of course the problem is that the capac
Re:True. (Score:2)
It may deliver a longer shock than a capacitor can deliver. But nonetheless it's best to always remember, there is nothing a commercial product can do that cannot be made at home.
If they can build it, you can build it.
Man.... (Score:3, Funny)
Anyway, what I did when I was a teenager was wire up an old shocking pen with two wires, attached it to a telescoping antenna, and made a prong at the end out of a binder clip and two paper clips. I went around pronging everybody.
Re:Man.... (Score:2)
I made one a while back... (Score:2, Interesting)
www.n17ikh.com/images/stunner1.jpg
www.n17ikh.com/images/stunner2.jpg Brings "Curiously Strong" to a whole new level.
Explosive Capacitors (Score:2, Interesting)
Re:Explosive Capacitors (Score:2)
When Dielectrics fail, they spot fail. A small piece cooks and becomes conductive, and the lowered resistance in that spot keeps the failure from ocurring elsewhere. Some metal to spread that discharge area out and decrease it's resistance could cause a quicker discharge, as well as serving as an EMP antenna.
Make a cap with a dielectric with a specific breakdown voltage. Make an ultrasmall charging circuit that runs off a watch battery. Make a
Re:Explosive Capacitors (Score:2)
Comment removed (Score:4, Funny)
ah, the camera flash (Score:2)
Re:ah, the camera flash (Score:2)
Not true or no longer true.
Kodak pays 3 cents for the camera (even if not theirs) and 5 cents for camera and AA or AAA. Every two weeks or so somebody comes to the lab I worked at. She counts the cameras and batteries, lining them up nicely, and hauls off two big bins for recycling.
Yay, more uninformed stupidness on TechTV (Score:5, Interesting)
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.
Easier method yet.... (Score:3, Interesting)
Nail clippers are not illegal.... (Score:2)
My Potato Gun (Score:2)
Stun cane? (Score:2)
Would such a thing be illegal to carry?
Question to people with more experience (Score:2)
Tim
Old Hat. (Score:2)
I remember this from 1993 (Score:4, Interesting)
How to make a ZaPPeR GuN
By Panther Modern TNO/TBF
The zapper gun is kinda like a commercial stun gun. It is not as
powerful, and is mainly used to piss people off, not to put them down.
It will scorch skin very painfully, if applied. Total cost for it is
around $20-$25, and it is a fun thing to make if yer kinda bored.
If you don't know what a capaciter is, read no further, go find out
what one is/what one looks like, then come back. Anyway, materials
are:
Qty Description Approx price
01 Disposable Fugi-Film FLASH camera $15+TaX
01 Small-Mid radio shack projekt BoX $2-$3 or so..
02 Dry wall nails 10-20 cents
01 Radio Shack SPST Push Button $1.50
01 1 Alkeline AA battery $0.50
This is to make a fairly nice version.
For the raw, crappy version, all you
need is the camera. I won't even go
into details on making it, you can
figure it out for yerself.
Okay. Get the camera. If you want, take some pictures. ALL OF THEM,
or none of them. Cause if you don't take all, you'll ruin the film..
Now, when yer ready, first, rip off the cardboard. You'll have a plastic
box. Open it up, as well as you can. Be very careful not to damage the
circuit board, wires, flash, etc. Once it's open, discard the plastic
case, and the film. Now, looking at the circuit board, one can see
a fairly empty space. Rite in the middle of it, will be 2 small copper
"plates." Soldier your button to this place. YOu may also remove the
flash at this time, as it will be shortly rendered useless. Also, you will
notice two protrusions of copper strip. Pull 'em off, and MAKE SURE they
aren't touching when you finish, cause it will ruin the gun. Next, put
the circuit board in the project box. Drill one hole so you can see the
LED. THis will tell you when the gun is ready to FIRE! (When the LED
flashes). Next, line up approx where you want your two tips. Line up
the capaciter with this. Drill holes. Next, drill one last hole where
you want the button. Now, remove the generic AA battery in the camera,
replace it with your hi-quality Alkeline AA battery. Now, stick the nails
in, and soldier them via wires to the two capaciter leads. Seal them in
place with either expoxy or hot glue. Now, wire up your button, and stik
the LED in the hole you made for it. CLose up the box. Your gun is made..
Just push the button, holding down for apporx 2 seconds until the lite
flashs, and touch whatever you want to SHOCK. This gun is semi-lame, but
is also fun, and good for boredom..Have PhUn!!
Re:Security? (Score:2)
Yea, god forbid they ever hear of capacitors. Because, you know, there aren't any electronics in the middle east.... I'm sure nobody East of Greece has ever gotten shocked by a TV capacitor or anything. Nope, they've never heard of such things.
Re:Security? (Score:2)
You know I wonder sometimes about such things...
I mean, they obviously could have thought of this plan at any time. But they either haven't thought of it or haven't done it yet for some reason. At least some of these plans, some people believe, have some chance o
Re:I think I speak for everyone here.. (Score:2)
Not only old, but... (Score:2)
Wow, the article doesn't even show a picture of the completed device.
Re:Not only old, but... (Score:2, Funny)
Re:Talking about idiots at airports... (Score:2)
Too bad the US Government'
Re:Talking about idiots at airports... (Score:2)
"killing terrorists will just make martyrs out of them..."
Well, good. I find martyrs are very bad at killing people, being dead and all. Living terrorists have a much better chance at killing people.
Re:OK... And then what's next...? (Score:2)
Or at least some model rocket engines and a heavy cardboard tube.
> personal mines using rat traps...
Plus a few shotgun shells.
Re:I wouldn't do this... (Score:2)
Re:I wouldn't do this... (Score:4, Insightful)
But if the capacitor is disconnected then the R in your equation is going to be a huge number. The voltage will still decay exponentially, but because the time constant is so big, it can take a while. As an example, if R is 10 megaohms and C is 100 microfarads, then it will take 1000 seconds for the capacitor to discarge to 37% of its starting voltage. So in this example, if the capacitor was initially charged to 600V, then 15 minutes after it was disconnected it would still have well over 200V left to shock you with.
Re:I wouldn't do this... (Score:2)
Pretty sure there's a big math error there. Time constant is equal to R*C, so that's 10E6 * 100E-6, so that's 0.00001 seconds to discharge it to 37% if you put 10 Mohms across the terminals.
They don't discharge anywhere near that fast just sitting there unconnected, because the R is effectively infinite. Resistivity of dry air is *very* high.
What you
Re:I imagine (Score:2)
Needless to say, many people of all sizes shocked themselves with the camera that day. Nobody was stunned or even really hurt, but I suppose nobody tried to hold it onto their skin for a while (but its a capacitor so it shouldnt matter that much...)