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Harvesting Capacitors for Backyard Munitions
Diabolus writes "This is the tale of a man, a bunch of disposable cameras, and his techniques for harvesting lots of capacitors to build a gauss gun. Insane..." A basic capacitor tutorial is probably in order.
And I bet it still won't work....
"The best argument against democracy is a five minute chat with the average voter."
--Winston Churchill
I remember taking apart the Data Checker system that was manufactured by National Semiconductor in 1979 which I acquired from my highschool. It had some of the largest capaciters I've ever seen. The largest one was probably around 4 inches in diameter. If only I had had this guy's idea first.... :)
The Moo went "Cow!"
Isn't it, oh, I don't know, kind of illegal to manufacture weapons that far surpass anything the army currently has, or will have in the next 20 years? =P
Mechanical Engineers build can crushers with moving parts.
Electrical Engineers build can crushers with no moving parts.
However, whatever the discipline, no mad science lab is complete without a Furby Testing Program.
Fire and Meat. Yummy.
isn't it easier to read the damn article instead of making assumptions.
There you will learn that instead of buying tons of cameras, he is friends with a local store that would rather give them away/pitch them than go through the hassle of sending them back to Kodak for reuse.
fry a diode, for example
My life in the land of the rising sun.
No info on flux capacitors? Damn, guess I'll never get back to the 2030's...
c-hack.com |
Yeah, so he's got a bunch of "basically" free caps. Now what? Solder a bunch together?
Seems like a lot of work for a huge mess of solder and wires for what would amount to a fraction of what a single car-audio capacitor would put out.
Am I missing something, or is his time worth nothing?
Karma: Excellent
WTF?
isn't it cheaper to just buy caps insted of disposible cams
This place has a great supply of large high-voltage oil-filled capacitors salvaged from all sorts of stuff.
High voltage capacitors can be tough to get - Radio Shack doesn't stock many of them, and sometimes you have to buy them in bulk, which puts them out of range of most experimenters.
Microwave ovens are a great source of parts if you want to play with stuff like this, but it's worth noting that there's stuff inside microwave ovens which can kill you if you look at it the wrong way.
A full-wave rectifier made of microwave oven diodes, or a voltage doubler made with microwave oven diodes and capacitors, can be connected to an old microwave oven transformer for all sorts of fun, but can provide more voltage and current (ie. more power) than an electric chair. Be careful.
This sort of setup is great for charging up those 1uF 10kV oil-filled plastic capacitors (or doorknob capacitors) you might be able to scrounge up by looking in the right places. Oil filled caps are great because they tend to be self-healing. Blow a hole in the oil dielectric, and more just flows into place to fill it.
They're great for spot-welding.
Please don't do this if you don't known what you're doing, and I can't take responsibility for telling the wrong people stuff they can figure out from reading an electronics textbook.
Fire and Meat. Yummy.
I'll second the request for pictures/description of the finished product.
I built a very small gauss gun in high school, played with capacitors (and other high voltage devices, like the infrared viewer I built), and generally had all kinds of fun.
But I wanna see this thing fire...
Specialization is for insects. - R.A.H.
Be careful if you try this; those capacitors hold a fair amount of charge.
My brothers and I played with some of them in the kitchen at a family gathering a few years back. One of them is in the biz, and had more used, disposable cameras then he knew what to do with. We were bored and trying to rig up something ad-hoc (as I recall, we were using whatever we could find in the kitchen--rubber bands, tupperware, etc.) Our wives were in the dining room with the everyone else, and we weren't being very structured about it.
Things were going fairly well until we accidentally shorted something. There was a loud bang, a flash, and one of us jumped back, knocking over a pile of pie tins.
All conversation in the dining room stopped, and after a moment our mother's voice called calmly: "What are you boys doing in there?"
Without missing a beat we all replied, in unison, "Nothing!"
It was like old times.
-- MarkusQ
Capacitors, Australian for bored.
Does this mean we won't be able to take disposable cameras on to planes any more?
Imagine the memo to baggage scanning technicians:
"WARNING: Any passengers attempting to take large numbers of disposable cameras on board any flight is a terrorist. These cameras can be used as a weapon by assembling a gauss gun from their parts. Call your appropriate superviser IMMEDIATELY if you have any suspicions"
Reading. You shold try it some time.
If you had, for instance, you would know he is not done collecting enough capacitors yet.
Moon Macrosystems. Sun's biggest competitor.
just slightly radical
http://obelix.cs.adelaide.edu.au/
"It is a greater offense to steal men's labor, than their clothes"
while this is cool and geeky as f*king heck... it's a bit over done.
1) you can buy capacitors for less trouble. true, large 330V caps does cost money and he is getting this for next to nothing, but i think it's better to shell out a couple hundred bux for components for that gauss gun instead of subjecting myself to hours upon hours of de-soldering and discharging capacitors and getting flashed.
2) if you *really wanted*, you can also pull caps off old TVs, or any CRT in general; and they can go up to 20kV! heck man... for self-mutilation fun, doesn't 20kV sound better than 0.3kV? (erm... becareful when you do this. those caps can hold charge for like 20 years)
3) you can achieve the same with a large (i mean gigantic) low voltage capacitor, which would actually handle more current anyhow. (car) Audiophiles probabbly know what i am talking about. there are 10-15V capacitors for your huge woofers that carry up to 10 FARADS. nope you did not read this wrong... 10F, no m,u,n,p; straight up 10F. if you wanted the high voltage, either build yourself a HV transformer (easy) or salvage one from a junkyard (you know, ignition system).
but otherwise, rock on. i would like to see the 5kJ gauss gun in action someday, preferably tested on a furby or something
My life in the land of the rising sun.
I have a very large vacuum capacitor which I'm not sure what to do with. It looks really neat (images: http://novalis.org/images/photo/vacuum_capacitor/) . The glass is about eight cm in diameter.
Does anyone know anything about things like this? Is it worth anything?
Become a FSF associate member before the low #s are used
I remember my friend and I in 1992 to sitting around and playing with capacitors. We were even getting paid. We were hooking them up reversed polarity on a small DC power supply. They EXPLODE. We were doing small caps. Big caps would be too scary. We were putting them in the McDonalds quarter pounder with cheese styrofoam boxlets that were sold back then. Remember those? They add to the effect. I will always have that mental image of DC power leads running out of a closed McDonalds QPw/C container.
No pictures/videos at the site mentioned in the article, but here's a different site with videos of a capacitor-powered gauss gun in action:
Anyways, I was responsible for 4 complete goobers and one gorgeous blonde (who really dosent have anyhting to with the story, but I just want to mention her), which was not an enviable task. They got bored on the plane to hawaii and took apart their disposable camera ... well low and behold they figured out about the only thing you can do with a broken disposable camera is shock shit or get shocked. After some dumb luck (getting shocked in the first place) and some trial and error, they figure out if you touched these leads and pressed that button youd get shocked ... so the next step was to walk around the plane getting people to hold the leads so they could shock them (someday Id like to know why you would hold two leads a 14 year old asked you to).
So one afternoon our scheduled activity was to hang out in this park because thats damn cheap :) and well now you have to know about the director ... he was this big fat, raunchy, disgusting fat fuck who happened to be one of the best directors in the nation, and he had this even fatter and even rauncher wife their two skinny (but soon to be fat kids). The wife was horrible annoying and the kids were even worse, the whole band was sick of them. Meanwhile in the park, the band was getting pretty restless, shocking eachother with cameras actually became entertainment :) So these guys I am responsible for are shocking eathother, Im hitting on the blonde (amy hays if you're out there... ;-) ), and oie of the directors sons walks up and he says "Hey what are you guys doing?" (the kid couldn't have been more then 6 or 7) One of the worst jerkoffs in my section gets this HUGE grin on his face and he says, "I'll show you. you touch this and this, and then press this button" Meanwhile I look over and see whats going on, as Im screaming "nooooooooooooooooooooo!!" in slow motion like the matrix, the kid shocks the crap out of himself and I swear he almost pissed his pants as he took off running. We never got in trouble so I dont suppose he told his father :) but we were paranoid the whole rest of the trip.
on an unrelated topic, couldn't this guy just buy a couple 1 farad capacitors? Those are pretty popular with car audio buffs, they run maybe between 100 - 200$ a piece, I think that would be so much easier then getting UV burns like this guy is describing :D
Religion is a gateway psychosis. -- Dave Foley
> I get this:
Karma: Terrible (mostly affected by moderation done to your comments)
Obviously there's a bug in the system. -13 karma isn't terrible, it's a badge of honor.
I caught myself laughing out loud to that one!
Does that mean I am now a troll?
Somebody must have turned down the thermostat in hell!
Karma: Excellent
WTF?
It doesn't take very long to realize you're getting slashdotted if you're paying attention.
Yeah. First, you notice that kmail seems to be taking longer transferring mail than usual.
Then, you click on a webpage link, and your usually-quick DSL feels like dialup again.
The hard drive in your webserver is scratching so much, it's hard to think; it sounds like you're compiling a kernel and making a divx at the same time, but it's pages being served and visits being logged.
You fire up top and are greeted by a whole screen of httpd daemons and CGI.
Congrats, you're being Slashdotted.
It's actually kind of fun.
Fire and Meat. Yummy.
Hey, your list has no "collect panties" step in it. Something must be a-miss.
Table-ized A.I.
(* Does anyone else think a Gauss gun, or similar EMP device would....winning robot wars? *)
I would like to see explosives and guns allowed on those things. Of course there could be no live audience, but it would make for great TV.
Robots machine-gunning each other. Now *there* is pure geek male testosterone at its best......better than the 3 stooges.
Table-ized A.I.
Back in high school, a friend and I made a Marx Generator from about 7 of these capacitors. The flash tubes in these cameras make wonderful spark gaps, BTW. It took about 30 seconds to charge up the thing, and the output from it lasted for mere picoseconds, but dang was it cool.
P.S.: Word to the wise: just the task of putting a load across the output terminals can set one of these things off. I was moving one of the terminals with a metal screwdriver and I accidently touched the other contact with my other hand. To this day I do not know how I managed to survive that one.
--- "...And everybody died!!! Except for me, of course...you know why? Because I had my tray table up...and my seat ba
First of all, there are no pictures of a gauss gun, because it doesn't exist yet. I have the parts for an inverter to charge it, but have not yet assembled it. Not having had much experience with switch mode power supplies, I'm just hoping it doesn't burn down.
For someone else's (working) effort, check out powerlabs.org
As to those who think car capacitors, etc might be better, they have a very low voltage rating (eg 15V). E=0.5*C*V^2, so even with a farad the energy isn't that great. Secondly, they are made from *thin* foil and have crappy current ratings, not much good for generating 10kA for 1ms. These are photoflash-rated caps, intended for 1ms discharge times - thick foil, good dielectric and some actual quality control.
Lastly, the capacitors will have to discharge through an inductor, even if it is only a couple of turns. Lack of voltage means the current rise is too slow (dI/dt = V/L) and so a low voltage, high capacitance bank will not discharge fast enough. Slow discharge means the ring has moved away before it receives much energy.
I'm also missing large silicon devices to actually discharge the thing. SCRs that can handle 10 or 20kA are not common and seem to cost many hundred of dollars. If anyone's got a spare one, please tell me! Otherwise I will have to make do with lots of smaller devices from surplus shops and build it multi-stage with messy triggering.
As for energy, consider 0.5*m*V^2. Given about 3 to 5kJ and about 2g of mass, you figure it out. It will be lucky to get 1% efficiency, but still. If it works well, I might have to look into firearms licensing. Big deal.
To those who say "you're a dickhead, that's lame", well, fair enough. Its not for everyone, and this page wasn't put up for the express of having it critiqued by /. bottom-feeders. I guess you could say "that's just sad", but if you're not an eleceng then you're not going to get what's interesting about this stuff.
Grandparent correct, As the owner of a few car audio shops, nothing made my day more than selling stuff to kids who thought they needed it. The sales pitch was always based on some fragment of truth then a wild jump to a $200 solution. In the case of the caps, the fragment of truth was that the voltage at the back of the car dropped when the amp sucked some current. The REAL answer is both of the following: 1: thats how electricity works 2: the effect can be minimized by making sure your connections are solid (the drop is caused by resistance, NOT the fact that your battery cant keep up to the demand.. the battery can run your starter at a couple hundred amps)
The real answers arent all that profitable, nor are they very cool, so we sell you big caps, and your friends drool with envy at your new equipment while you pretend to hear a big difference in the sound. The same principle drives the music/clothing/other industries... 'the dumbest buy the mostest'
Have you ever played with a car amp that needs 1000 watts?
No, and neither have you. 1K watts is about 1.5 HORSEPOWER. In recent years, many manufacturers of car audio equipment have been competing for your money by putting really large numbers on the cases of thier devices just because it makes kids buy them. Take the average radio.. a good one claims to do 40 watts per channel, on a 12 volt powersupply and a 4 ohm load, the maximum possible output wattage is 36.. and thats assuming a 100% efficient amplifier (which doesnt exist)
According to the ATF it is not illegal to make your own gun provided it is not a semi automatic and the person is not making it for sale and the person is allowed to possess a firearm.
A7) Does the GCA prohibit anyone from making a handgun, shotgun or rifle?
With certain exceptions a firearm may be made by a nonlicensee provided it is not for sale and the maker is not prohibited from possessing firearms. However, a person is prohibited from making a semiautomatic assault weapon or assembling a nonsporting semiautomatic rifle or nonsporting shotgun from imported parts. In addition, the making of an NFA firearm requires a tax payment and approval by ATF. An application to make a machinegun will not be approved unless documentation is submitted showing that the firearm is being made for a federal or state agency. [18 U. S. C. 922( o), (r), (v), and 923, 27 CFR 178.39, 178.40, 178.41 and
Mine too... I wonder what the new ranks may be; CmdrTaco, Excellent, Great, Good, Average, Below-Average, Loser, Whiner, Troll, goatse.cx and Bill Gates? :-)
Money for nothing, pix for free
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Actually, don't knock old tech. I'd feel safer in an F-18 than in an Osprey. ;-)
Actually, the president of my old college had a great story about how old tech can be superior in performance. He was a former Deputy Dirctor of the CIA, and had some stories he was willing to tell about some of the declassified things he was involved in. One of them was the study of the first MiG fighter we got our hands on.
Back in the 60s we were afraid of these new MiG fighters the Soviets were using--they performed significantly better than out own fighter jets of the day. We couldn't figure out what it was about them that made them more maneuverable and faster, but among other things we were scared that they had more advanced onboard electronics.
We finally got our chance to find out when a Soviet pilot took a MiG to Japan to defect to the U.S., and my college president's team was called in to disassemble, photograph, and reassemble everything before the Soviets came to retrieve their fighter the next day.
So, do you know what those sophisticated electronics we were afraid they might have developed were? Vacuum tubes. Yep, those early MiGs that outperformed our own fighters were still using vacuum tubes, a technology ten years out of date; our fighter electronics had long been transistor based. The advantages of the MiG turned out to be nominal design differences and nothing more--no super-sophisticated technology at all.
So, don't knock it 'cause it's outdated tech. The proven F-18 can still kick the ass of many newer more sophisticated designs when ity comes down to brass tacks.
Chasing Amy
(We all chase Amy...)
"The more corrupt the state, the more numerous the laws"-Tacitus
It's a Good Thing(tm) and I bet it will deflate the karma issue just as changing story ids from initiating at 1 for each story deflated the first post madness (not that the fp'ers have gone away, it's just a lot less important to most people what sequence number their post "gets").
/. readers tend to be a little bit, err, fanticaly devoted to the mathmatical arts.
:-P
Uh bull shit;
most
And you see, we LIKE keeping track of meaningless numbers. For one thing it tells how close I am to getting my +1 rights removed so I knwo when exactly to stop telling as many people to Go Fuck Themselves quite so often and ease up on the language a bit;
besides I get to (used to get to?) do nifty statistical analysis on the numbers (in my head of course, not gonna spend time to write anything down, yeesh) and figure some shtuff out;
such as if I made a net karma Gain or Loss from posting a pro-MS post. So far in the past I have seen strong chances of me getting a net moderation UP after a thread then down, rather cool actualy.
Need help treating your acne? Come here!
Here's a new weapon idea!
How about building a device that charges these small flash caps and then fires them out as projectiles. Anyone unfortunate enough to get hit with the contacts gets "knocked on their ass" as many experimenters have discovered.
I'm gonna pop a 0.22 Farad cap in your ass sucka!
Here are a few different Gauss Guns, including the one from Half Life!
Yes, I did just pilfer these sites from Google, but didn't see any other references linked so far, soooo.....
Yep, those early MiGs that outperformed our own fighters were still using vacuum tubes, a technology ten years out of date; our fighter electronics had long been transistor based.
However, vacuum tubes are highly resistant to the effects of a nuclear EMP which would have been a big concern in the 60's. The irony is that had there been a nuclear exchange the tube-based MIGs would likely have still been flyable while the 'better' American planes would have had their electronics fried.
Next week we'll see an article on eleceng geek defense contractor startup.
None of which is actually relevant, seeing as this is not a firearm. There may be applicable laws (I'm sure there are, but probably not any) but the stuff you are referencing simply doesn't apply to gauss guns anymore than it does a homemade crossbow or staff-sling (either of which would probably be comparable for destructive capability with this guys gauss gun, if he ever gets it working, btw.)
=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Friends don't let friends enable ecmascript.
My EE advisor in college was fond of saying:
... once."
"Any diode can be light-emitting
I stole this sig from someone cleverer than me.
one of the parts mentioned here is labeled as such
http://obelix.cs.adelaide.edu.au/album/cooling/ind ex.html
although his working version does use something else
http://obelix.cs.adelaide.edu.au/album/cooling/ins talled/index.html
"It is a greater offense to steal men's labor, than their clothes"
Umm, minor detail I cap of hat size wouldn't have a very high voltage rating, 500V if you're lucky. Above that, and it'll likely arc across the dielectric letting out the "magic smoke".
You can hit a million volts by placing lots of 'em in series to build up the voltage withstand. Of course, you reduce the capacitance with each series connection, so you make a string long enough to withstand the voltage and then parallel strings to get your capacitance up.
At 1MV, 5F is one *whack* of charge. Wow my mind hurts just thinking about it.
90% of the cost of disposables is the film and the developing.
:)
Photo labs often have huge boxes full of used cameras, just ask for a few.
Officially they're supposed to send them back for recycling into new cameras, but it seems that their rewards for doing so aren't very great - So they usually are willing to give away a bunch for free.
retrorocket.o not found, launch anyway?
High school electronics class was a fun time..
I used to charge up small capacitors and place the leads between the pages in my books. When walking the halls between classes, I would pull them out and shock people. Our halls were pretty crowded so you could be very covert. We also used the capacitor tester as a wimp detetector. Five or so people would hold hands with the end people each getting one of the charging leads. Another person would slowly turn up the voltage until someone wimped out and let go. Normally that person also got a little extra from the resulting arc.
Bad boys rape our young girls but Violet gives willingly.
Well, you are right about the 36 watts. But many car audio amplifiers use inverters these days, allowing them to increase the voltage manyfold. Thus they may have fifty plus volts to play with (no pun intended) and can output many watts... but usually these are not RMS (continuous) watts, but PMPO or some crap like that.
there is no spoon
Exactly right. But at least they're a good source of free AA batteries for us photolab monkeys.
You could do surgery on the sidewalk there [in Switzerland] without causing an infection.
A slight exaggeration, I'm sure, but point taken. There must be _some_ Swiss criminals, but the worst thing I've ever heard a Swiss accused of was a sort of bureaucratic crime - just keeping any money deposited by (probably dead) German jews before WWII in Swiss banks unless someone could actually prove he was the heir...
I do wonder though, how much of their good behavior comes from every man going through boot camp (for centuries), how much from the knowledge that your neighbors have as much firepower as a regular infantryman (although I've heard that a Swiss who uses his military weapon without authorization goes to prison longer than the average American murderer), and how much from other factors...
That'd be a real kick in the family Joules. A million people at once saying ... "
... about 12 million of them. At $100 each, a mere $1.2 billion would suffice. Get out the platinum card and head to Best Buy.
" Cool! umm
(say it fast and remember your physics)
You could build this out of ordinary car audio capacitors
You can never equivocate too much.
When I was a senior in high school, a group of us would hang around in the ahlls before calss and talk. Most of us were "mad-scientist wannabes", and we would discuss our current projects (one guy was trying to make napalm, IIRC).
Anyway, there was this one sophmore who hung around with us, who was always trying to immitate our projects (usually badly). He was ok, I guess, and it was usually funny to listen to his recent mistakes/problems (like accidently land-mining his room in the middle of the night with exploding paper strips.)
The hallway at our school were long, with lots of glass, and metal rails running along at about waist height. Usually, all the students would lean against the rails before class.
Well, one guy in our group had torn apart a disposible lighter and had gotten the electronic igniter out of it. He would touch the wire to the railing, and when he pushed the button, everyone touching the rail would get a shock (very minor shock). It was irritating and fun!
Well, this sophmore decided to "one-up" us, and managed to get hold of the igniter from a gas stove. The thing was about 10 times as big as the small igniter, and produced a nice, fat spark when pressed.
IIRC, he managed to shock himself, while the rest of us stood around laughing. I think he finally gave up on trying to shock anyone with that.
-Ed
docbrown.net
Graphic Design, Web Design, Role-Playing Games...all the good stuff
Ed Wedig
Graphic design services
docbrown.net
Using mostly stuff I have lying around in my garage workshop this weekend, I can fry most of the chips in the average server farm, telephone switching facility or the radios used by police, fire and emergency services. If I did it right, I can 86 all of the above at the same time.
... said someone would call me back. Not.
e p/2001/a u-221-e.html
>
h n/metalfor minghb/tabofcont/index.html ... and monitoring sales could be an early warning. If you can get the manufacturers to look for suspicious purchases it could be a good tripwire.e rovox.com// ppti2.htm lp erplast icity.htmlk er_Chronic les_II/pyro/miss2.txte mon.co.uk/anarchy/bomb/ bombs-1.html ....1 /a u-221-e.html
Indeed, I can zap all the control circuits in a modern fly-by-wire jumbo aircraft and make it do a ballistic imitation of a large brick. If I time things right, I can bring a fully fueled jet down right in the middle of San Francisco.
Can you say "9/11?" Sure you can. So here we are, nine months along, and those who are supposed to protect us are as clueless as ever.
I could create total electronic chaos and another 9/11 with a homemade, explosively pumped, flux compression generator, and I can do it with data I found on the Internet, including some very helpful stuff from the Los Alamos nuclear lab web site.
We're talking here about an electromagnetic pulse (EMP) weapon, the neutron bomb of electronic circuits. A garage EMP bomb is amazingly easy to build, especially with a 15-minute Google search.
Undoubtedly you have read about the EMP weapons we used in the Gulf War and Yugoslavia to take out air defense electronics. What you may not have read about is a 1995 incident when Chechnyan rebels used one to fry security circuits in 1995 to gain access to a Soviet facility.
Yeah, I've tried for months now to get anyone in power to care. Local law enforcement said it was not their table and to call the Feds. The FBI agent on duty in San Francisco was totally clueless
I used to work for U.S. Senator Thad Cochran. So I called one of the staffers I knew, and she referred me to the White House Liaison for Home Security. No call back there, either.
But maybe an EMP weapon sounds too much like anti-gravity boots and close encounters with Airstream trailer communities in the Mojave and that's why nobody returns calls and nothing gets done.
But realize this: the NATO document mentions the use of an EMP weapon by Chechnyan rebels. Al-Qaida includes many Chechnyans among the hard-core fighters, thus the usefulness of EMP weapons has surely been transferred to the bad guys still out there looking for an opportunity to make another big splash.
So, I couldn't just let the non-responses from the FBI and Homeland Defense be the end of the matter. With a little more digging on the Web, I located a DOE phone directory last week and called the folks who are head of security for the national nuclear labs. I actually got a call back and forwarded the information (below) via e-mail. I got a form e-mail reply, but the Los Alamos page (http://www.lanl.gov/dirac/) is still up there.
Why is the Los Alamos page important? Because it gives me a good look at an actual physical configuration of a real bomb that works. Taken together with the other web pages, it gives me an excellent chance to build a bomb that works.
Perhaps having the data out there for anyone is a victory for open info on the net, but then how easy DO we want to make it for terrorists? Where is the line between the free flow of information and discussion and giving folks easy access on how to build weapons?
EMAIL TO NATIONAL LABS SECURITY FOLLOWS
>Date: Mon, 04 Mar 2002 11:15:26 -0800
>To: marc.hollander@nnsa.doe.gov
>From: Lewis Perdue
>Subject: links
>
>Very nice chatting with you. Below are the major links I mentioned.
>
>Some detailed background on the threat can be found in a NATO Parliamentary Assembly report at:
>
>http://www.nato-pa.int/publications/comr
>
>I quoted from this report at the end of this e-mail. But particularly relevant is the following from that NATO report:
>
>"38.The possibility of terrorists using EMP weapons has been raising alarm for at least a decade among defence analysts. According to Winn Schwartau, an information warfare specialist, rudimentary EMP devices have been assembled by US Department of Defense consultants within two weeks at the cost of $500. Such devices, capable of disrupting computers, medical equipment and cars, could be placed in a van or even reduced to fit into a suitcase. Criminal organisations in Russia have been accused of using EMP devices to bypass alarm systems. According to the Russian Armed Forces, Chechen rebels might have used similar technology to disrupt Russian electronic communication equipment."
>
>As I mentioned to you, I can describe how such a device could be used to cause another 9/11-type disaster.
>
>links:
>
>THIS IS A KEY ONE: http://www.infowar.com/mil_c4i/mil_c4i8.html-ssi
>THE FOLLOWING may seem harmless, but the principles for forming metal, apply directly to an EMP weapon, both in learning how to acquire the capacitors for the construction, and because the electromagnetic pulse formation is very nearly the same.
>
>http://www.mse.eng.ohio-state.edu/~dae
>
>THE FOLLOWING ARE SOURCES FOR THE PULSE POWER CAPACITORS NEEDED
>
>http://www.nwl.com/
>http://www.a
>http://wwwcsif.cs.ucdavis.edu/~wiley
>
>
>YOU'LL WANT TO FOLLOW LINKS FROM THIS PAGE:
>http://er6s1.eng.ohio-state.edu/~daehn/hy
>
>SOME OF THOSE LINKS INCLUDE:
>
>Manufacturers of Pulse Power Equipment
> Maxwell-Magneform
> IAP Research
> Elmag, Inc.
> Pulsar Technologies (welding / crimping)
> Manget-Physik (German Mfr. of Electromagnetic Forming Hardware & MagnetoPulS® Technology)
> Kharkov Polytechnic University, Ukraine (research and equipment)
>
>Other sites related to high velocity deformation and/or hardware
>Pulse Power Equipment
> Richardson Electric (ingitrons)
> Maxwell Technologies
> Pulsed Power Technologies, Inc.
> Pulse Power Switching Overview
> Fantastically Dangerous Cap. Bank Experiments
> Aerovox Corp. (capacitor mfgr. )
> Darrah Electronics (solid state switching)
> Contents of IEEE Pulsed Power Conferences
>
>High Velocity Forming and Pulse Power Applications
> EMF Industries, Inc. (assembly with EMF is highlighted)
> Sparktec Environ mental Corp (uses sparks for water purification)
> Dana Corporation Develops Improved Magnetic -Pulse Process
> Electroimpact Home Page (mfr. of electromagnetic dent removers etc.)
> CONTENTS PAGE - RESEARCH AT SSAU (1997) (Russian welding, etc.)
> Simple Analysis from J. Krauss Electromagnetics Book
> Robert Hahn at IWF, Technical Univ. of Berlin (in German)
>
>IF YOU WERE DESPERATE FOR C-4 or Semtex for your EMP device, and didn't have a source for the ready-made stuff, you could try here:
>
>http://www.phreak.org/archives/The_Hac
>http://www.strange-days.d
>
>FINALLY
>
>New material continues to be posted on the Web. If you do a search for "flux compression generator" you will find more listings than just the ones above.
>
>
>NATO Parliamentary Assembly
>http://www.nato-pa.int/publications/comrep/200
>
>37.Yet another threat seems more imminent. As Ehlers indicated in his report, computer systems and all electronic devices can be seriously damaged by weapons producing electro-magnetic pulses (EMP). High Power Microwaves (HPM) or EMP bombs and High Energy Radio Frequency (HERF) guns can radiate intense pulses of electro-magnetic energy capable of severely damaging computers, radar and all electronic equipment. They can even destroy circuits, microprocessors and other components. These weapons are well-known in Russia, where extensive studies were conducted during the Cold War. The US Air Force used EMP and HERF weapons successfully in 1991 against Iraqi radar installations, and in 1999 against Yugoslav electronic infrastructure.
>
>38.The possibility of terrorists using EMP weapons has been raising alarm for at least a decade among defence analysts. According to Winn Schwartau, an information warfare specialist, rudimentary EMP devices have been assembled by US Department of Defense consultants within two weeks at the cost of $500.
Such devices, capable of disrupting computers, medical equipment and cars, could be placed in a van or even reduced to fit into a suitcase. Criminal organisations in Russia have been accused of using EMP devices to bypass alarm systems. According to the Russian Armed Forces, Chechen rebels might have used similar technology to disrupt Russian electronic communication equipment.
>
> 39.In his book Cybershock, Schwartau considers some possible effects of a well-orchestrated EMP attack upon Western infrastructure:
>
> Wall Street or other banking systems can be attacked, causing repetitive failures resulting in financial losses. Also past records can be wiped out by onslaughts of electromagnetic pulses; aircraft avionics and guidance systems can be overloaded by targeted HERF, causing potentially deadly conditions; medical equipment can fail under the attack of intense energy spikes, putting human lives in danger; communication nodes can be burned out by intense microwave radiation; municipal emergency services can be made inoperable by debilitating wide-band microwave jamming; power lines and transformers may serve as efficient conductors to transmit huge current to victim businesses and sub-stations, causing regional black-outs.
>
>40.The ability to build EMP weapons is apparently quite widespread, yet there are no international controls over the import and export of the related technologies. Defensive techniques, although in some cases expensive, have been partially deployed in the public sector (especially to protect military assets), but remain extremely rare in the private sector.
Fill a can with a little bit of water and set it over a flame until the water begins to boil. At this point most of the air has left the can and been replaced with water vapor. The can will not implode yet,
Of course! Chemical engineers build their own can crushers.
Do any of the other disciplines do this, that we can think of? Aerospace? Civil? Structural? Software?
Fire and Meat. Yummy.
OK, so how comes I'm the first person to write that?
---- Den ene knappen er powerknapp, den andre er Bender voice knapp "Bite My Shiny Metal Ass"
All I got was a puddle of half-and-half and a wet lighter...oh, NON DAIRY creamer! Ooops...
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
Well, the one I built is 30mm but it isn't a semi-auto so I guess it is ok.
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
If I had access to high explosives I'd just blow up the thing I wanted to destroy and save myself the trouble of screwing around with EMP. Hell, if I had a nuke and wanted an EMP bomb I'd put it on a rocket (if you can get/build a nuke you can get/build a rocket too) and detonate it in the ionosphere and generate one hell of an EMP pulse via nature! This actually happened once in a high altitude nuke test to Hawaii.
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
> I'm also missing large silicon devices to
> actually discharge the thing. SCRs that can
> handle 10 or 20kA are not common and seem to
> cost many hundred of dollars. If anyone's got
> a spare one, please tell me!
High-current SCR's are expensive, that's for sure. Do you really need a fast cycle time, though?
I know somebody already suggested a mechanical switch. Given the energy levels you want, it's probably not very realistic to use a knife switch.
A liquid-metal contact switch at least wouldn't weld itself together every time you closed it. Good luck finding one of those that's a) in your price range, and b) not full of Mercury, though.
Have you considered a spark gap? Since your working voltage is (relatively) low, you could use a triggered gap as a switch. Sort of like the flash tube, but built a lot more rugged.
Take a look at some of the web pages out there devoted to voltage cascades, Marx generators, and Tesla coils. Maybe someone has a solution figured out already.
Or, how about a vacuum tube? Peak current might be an issue there, too, but the voltage range seems about right, anyway. I'm no vacuum tube expert though.
-Mark
Take the average radio.. a good one claims to do 40 watts per channel, on a 12 volt powersupply and a 4 ohm load, the maximum possible output wattage is 36
The radio you describe is the same bridge output amplifier that a few years ago was rated at 12.5 watts per channel, or 25 watts for 2 channel or 50 watts for 4 channel. It's the same voltage into the same load. Nothing has changed but the numbers.
Because people tend to by things by comparing the fancy numbers on a spec sheet, lots creative writing has been done to seprate fools from their money.
#1 Rate peak power instead of RMS average watts.
Explaination; Music is not DC heating power. If you take the maximum DC voltage and figure the power based on load resistance, you can get a high number. In the example given, 40 watts was tossed out. It was pointed out that that number refuted with a supply of 12 volts. It wasn't figured at 12 volts. The charging system provides about 14 or more volts. Redo the math with this number.
An audio waveform is not a sine wave. The peak possible voltage is not provided to the speakers 100% of the time. In the '70's some good stuff was rated at RMS power at a specified distortion level. In the above case, 40 watts is only possible with the engine running and the speaker voltage never leaving peak values. In short a very distorted square wave output. Not pleasant music in my book. A 6 Watt RMS rated amplifer at 0.1 THD is a much more powerful amplifier. My favorite amplifier is rated 25 watts RMS per channel at 0.04% THD into a 4 ohm load. Some amplifiers are rated to provide their rated output only a very low speaker impedances. 2 and one ohm are common. Almost half the power rating for these as they can not provide the voltage needed to properly drive rated power into a 4 ohm speaker. Needless to say, that rating will misslead most newbies in the audio field. The don't understand why my 50 watt amplifier uses 8 AWG wire with a 20 amp fuse. They are also supprised when I connect a scope and show it provides more unclipped peak to peak voltage to the 4 ohm speaker than most amplifiers rated 200 watts. Yes the honestly rated 25 watt amplifer is a bigger and higher power amp. That rating is not a peak power rating. Learn to compare apples with apples. Is the spec peak or RMS? Is that rated into 4 ohm, 2 ohm, 1 ohm? Is that rating guaranteed at 11 volt supply, or does the amp need to be under the hood getting 14 volts direct with no power distribution system to provide voltage loss due to resistance and distance? If you have a 200 Watt RMS into 4 ohms rated amplifier, I'll be looking for serious hearing protection! The car audio market is "let the buyer beware". The specs on paper are deliberately missleading. Borrow a scope and a dummy load. Find out how much Peak to Peak voltage the amplifier will deliver before before clipping occures. Don't buy anything that will not put out at least 40 volts for a small amp and 80 volts for the super thumpers. Half these values for brige mode amps. I have seen stuff rated at 120 watts that are powered by an 8 amp fuse. 12 X 8 is only 96 DC watts in at the point the fuse will blow. (commenly spouted spec for cheap underdash EQ-boosters) Some power is lost to heat in the audio conversion from DC. How much is left for each speaker? How are they expecting to get 120 watts out with only 96 watts maximum in? That rating is not RMS average music power! There is some honest stuff out there. However bring your pocketbook. It isn't cheap!
Now onto the function of caps. Music has it's peaks and valleys. The resistance of the electrical distribution system is finite. It includes the wire, battery internal resistance and alternator internal resistance. Current draw over a finite resitance provides a voltage drop over the resistance. This is well defined in ohm's law. The current drawn by an amplifier is not constant. It varies. Simply the more the current draw over a fixed resistance the more the voltage drop. Because of this the voltage drop varies as the current drawn varies. The wiring can have it's resistance reduced by using bigger wire, battery resistance can be reduced by adding more batteries (and placing one close to the amp to shorten the wire from battery and amp).
To provide the maximum voltage to the amplifier at a music peak, the loss in DC voltage at the peak current draw can be acheived by providing the peak current from a local capicitor instead of through a long wire to the trunk. A big capacitor can provide the short duration high current the amplifier demands on a music peak, preventing the high current peak on the DC distribution system and it's associated peak voltage drop. A good scope will tell you in short order if the money is worth it. Watch the voltage drops on high power music at the amplifier with and without the cap. Saving a 1/2 volt peak drop may make a diffrence in a competition, but most people won't need it. Don't even consider adding a cap if your music peaks drop the supply voltage at the amplifier less than 1/4 volt. You don't need it.
The truth shall set you free!
I'm totally missing something here.
Aren't a bunch of cameras more expensive than just _buying_ big caps? And where would we get bags of disposable cameras?
https://www.accountkiller.com/removal-requested
Parking lot lights and other high intensity discharge lighting systems contain high current(to 55microfarad) capacitors. If you're looking to buy them here's Advance Transformer's catalogue for that sort of thing. Capacitors start on page 46. Their main page is http://advancetransformer.com
The previous has been a secret message to my comrades.
I didn't know there was such a law.
I'm in the process of converting a WGP Autococker into a CD/DVD Launcher - specially flattened barrel, tightened on one side to impart a spin - to launch Compact Disks with a burst of CO2. Although the CD's need to be loaded by hand, one at a time (up until recently), I can reliably attain ~550 ft/s. This is enough to cleave thick pieces of styrofoam/cardboard or aluminum cans in half... or embed itself into soft wood like Eucalyptus trees. Against harder targets, such as rocks, the rounds simply undergo fragmentation and splinter into tiny plastic chunks. I don't know the effects against animal matter yet, because the contraption is notoriously inaccurate and squirrels are annoyingly fast.
At higher velocities (~700 ft/s) the rounds begin to fragment in the "barrel".
Now, here's my question: I've put together a rudimentary feeder/hopper that now lets me use my CD Launcher in a semiautomatic fashion, and believe me, having played paintball for four years straight, I can pull that trigger pretty fast. Is it a gun? Does it need special attention from the ATF?
Let's thicken the plot: I'm slapping together a solenoid-actuated electric trigger frame (similar to a Sandridge) to convert my paintball^H^H^H^H^H^H^H^H^H CD gun to a fully automatic weapon. I estimate a ROF of ~13 CDs/second. (maybe *now* I'll be able to hit that pesky squirrel) My anticipation is that it still won't do any damage to brick walls, bronze statues, and masonry of quality craftsmanship, but will absolutely *shred* old wooden fences, thrown-out sofas, and squirrels. Will it need to be registered with the ATF then?
BTW, I once thought of calling it my Assault Ordnance Launcher, or AOL for short... the idea being that people would soon become afraid of my AOL CDs...
Solomon
"Twice half-assed makes an ass whole." --Solomon K. Chang
In any case, you one can generate much more power than a lightning strike without using as much energy. Also, if designed properly, some portion of the mechanical energy from the chemical emplosion gets converted into additional electrical output. A short durration and short distance arc also ends up generating much more of its EM radiation in a frequency range more destructive to aircraft.
If one were to have the TNT to make an EMP bomb, one could think of much simpler ways to take out jetliners, not all of which would require bypassing airport security. Supposedly Al Qaeda looks at action movies and the internet for ideas, so let's no enumerate the possibilities here. Let's just take it for granted that if someone has 5 or 25 lbs. of TNT, EMP bombs are not the biggest threat the FBI should be looking at.
Copyright Violation:"theft, piracy"::Anti-Trust Violation:"thermonuclear price terrorism"<-Overly dramatic language.
I just had to dig out the scope and check my claim to back up my 25 watts RMS is bigger than 40 watts Peak claim. Here is the facts. The amplifier is a Pioneer GM120 amplifier. I cranked it up into clipping with a load. I measured the output voltage Peak to Peak with a scope. (Tektronics TD 220 for those interested) The singel ended output clipped at 40 volts Peak to Peak. (clips at + and - 20 volts) That is for an amplifier rated 25 watts into a 4 ohm load at 0.04% THD. To provide this voltage, it uses an inverting switch mode power supply to provide the + and - voltage supplies. To match this in a bridge amplifier, (40 watt in-dash example) the supply in the unit would have to provide over 20 volts so each leg (+ and - speaker lead) swings 10 volts over and under their 10 volt DC rest voltage, or it would need a supply in the deck to supply high current to the output of + and - 10 volts for a bridgable or + and - 20 volts for a single ended output. They don't put that kind of power in-dash. It would fry itself due to lack of proper heatsinks. The Pioneer amplifier swings a full 40 volts peak to peak on it's output. The in-dash unit will drive one lead (-) to ground while the other (+) swings to the supply voltage providing a swing of 24 volts P-P of one speaker lead refrenced to the other (14 volt car power). There is no way the 40 watt in-dash unit can match the 25 watt Pioneer with only a 12-14 volt single ended power supply. Remember that doubling the power into into a load is only 3 db gain. Doubling the voltage increases the power 6 db. (doubling the voltage into a resistor also doubles the current). With that in mind the 25 watt Pioneer is well over twice the power of the 40 watt indash unit into a 4 ohm load. 40 V P-P from the Pioneer is quite a bit more power than the 24 Volt P-P the in-dash unit provides.
The truth shall set you free!
And most car audiophiles are pretentious wankers.
That's very mild terminology. I can think of a few things I'd describe our local car "audiophiles" as, and none are as pleasant as "pretentious wankers."
These arseholes come in at 2 in the morning blasting their stereos. Their rice-buring piece of crap with a 14.20 qualifying time (hah, my '70 mustang is in the low 13s, stock engine, and weighs 1000 pounds more) written on the side window. They hit the gas, and it sounds like my dad revving his lawn mower, only put out through a big-concert PA system.
You hear the BOOOM BOOOM of their barely-qualifies-as music, and listen to the trunk rattle, they sit ther for a few minutes, revving that whopping 2.0L engine up to 6000 RPM, and I'm sitting in my apartment praying the engine throws a rod.
To top it all off, it's 2 A.M., I've got insomnia, and I've already taken my medication, and can't have another dose for 20 hours.
Complaints to the police department, and aparment management do nothing, because the state has an $800 million budget shortfall, and the landlord is hurting for tenants.
These are the same people that go 50 in a parking lot where kids play, and the guy in the next building passed me at over twice my speed (I was going 60) on a highway that had a hit-and-run accident a few weeks earlier. I notice he's got a funny dent on his bumper, too. I'm tempted to call the police to report him as a drunk driver, but the local police don't take it seriously, even if the guy is driving at 120 miles/hour.
And yes, I've seen the amp and caps and speakers in his car. A true "audiophile," when the only quality you are looking for is loud and obnoxious.
"Alcohol, Tobacco, Firearms, and Explosives" should be a convenience store, not a government agency.
You're not thinking of car audiophiles, you're thinking of car bass addicts, whose only gauge of how "good" a system is is how loud the bass gets. Those are the people who decide what to buy based on what the popular rappers rap about in their songs.
There is such a thing as a car audiophile, and they will talk on and on about the sound stage, et cetera just like any other audiophile. However, car audio is so much more difficult than home audio that it doesn't make as much sense The car is driving through so many different places that the environment is constantly changing as long as the car is in motion. If you can make soemthing sound "good" in a that environment, then you are doing very well.
By the way, there are enough car audiophiles who want to be able to enjoy classical or jazz or whatever music in their Porsches. And if they spend $80,000 on a car and they like listening to music in the car, they can and do spend $8,000 on a system. Of course, many of these people are "pretentious wankers". They could easily get a system 90% as good for $2,000.
My other first post is car post.
I think it's really funny that my comment get's marked off-topic when /. has, on purpose, not provided a place where it would ever be on-topic.
/. shoot itself in the foot so often?
Isn't development supposed to make something LESS lame over time? Why does
In Soviet Russia...michael would be rotting in Siberia!
Yes. Start now. The more you know when you start the program, the more advantage you can take of the facilities offered to you. Get serious about getting started now and when your fellow classmates are learning Ohm's Law, you can be building stuff.
Tech Public Policy stuff