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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.
No pictures of the final product?
I have been pwned because my
I think a Gauss Gun is overrated, as i remember a research team built it in the early 90's, with little fanfair. It sucked.
About time they started back to lasers, methinks.
Think nothing is impossible? Try slamming a revolving door.
isn't it cheaper to just buy caps insted of disposible cams
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!"
Hello Slashdot! :)
Yes, the bandwidth is horrific, so I've shrunk all the images to a much smaller size (160 wide) instead of their usual 640 and 320. If you want to see this and actually make out the pictures (and read the text in them), come back in a week or so when the traffic has dropped and I've put the full-res ones back. Assuming I don't get firewalled off first
Anyway, have a read and a laugh at some geekiness.
Umm... something smells fishy around here, and it's not his wife!
Aw, fuck it. Let's go bowling. - The Big Lebowski
harvesting lots of capacitors to build a gauss gun. Insane...
not quite insane when he needs the gauss gun to protect his backyard from being invaded by the government...
i did enjoy how he prepared his website from the slashdot invasion.
Jesus saves souls and redeems them for valuable cash prizes
he'd make more difference contributing his time to free software projects (coding, testing, or documentation) than trying to create weapons. Make peace not war!
"As flies to the wanton boys are we to the gods; they kill us for sport." - William Shakespeare, King Lear
Hello Slashdot! Yes, the bandwidth is horrific, so I've shrunk all the images to a much smaller size
I'm amazed by his ability to fight the slashdot effect!
Everything will be taken away from you.
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
Some friends of mine and I have been discussing similar ideas. It turns out insane asilums usually have their own power plants which have sizable capacitors. Some years ago many were closed down and you can loot em if you watch your backs. =)
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.
(23:49:57) Me ok if I like blow a hole through my wall will my insurance cover it? :-/
(23:50:12) Leahana: umm if it is intentional.. maybe not
(23:50:18) Me:
(23:50:26) Me: ok I better go get the dog then
(23:50:34) Me: It's better to test on a moving target anyways
Anyone else willing to bet this will be modded -1: Cruel?
--
http://nemilar.net - Not your grandmother's soup kitchen
Remember in Fight Club, making explosives from soal, and also the fact that you can use nondairy creamer as an explosive. Cameras as gauss guns, damned cool.
To fend of Karma Whores and slow down Karma Racing probably.
Ohh I hope I get +1 funny for this.....
fry a diode, for example
My life in the land of the rising sun.
Sounds like a whole lotta effort just to win at Half-Life.
using namespace slashdot;
troll::post();
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?
wrong - guy's from australia
Remember the Gauss gun? When the grunt tried to use it and blew up the lab? Hope that doesn't happen to this guy.
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.
Go a level up & check out the two exam* jpgs - good laugh!
Is amazing what people can do with enough imagination, off course a rail gun would be better :P
I read the capacitor tutorial and started to feel like a "wanna go on ramapge hunting" strange valious capacitors, give names to 'em and join their energy, but later noticed sounded too much like pokemos so i went to play cs again...
Or a battery. Or a capacitor collection. Whatever. If it's not an item specifically excluded as military, then they have to prove that it's a military grade weapon. Which would probably require fixing it first so it would actually WORK. :)
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
> Wait a minute...so, low karma is bad? God damnit, I've had it backwards until now.
Nothing wrong with low karma...
In fact I'm hoping this gets modded down so I can find out what ranks below "Karma: Excellent"
Maybe it means the same thing as Karma=50 and I'm too dumb to know?
Why do you think it is, that most of us are illiterate? So that the government can trample on the constitution of course? You'd think the most important thing they could teach in school is what our 'rights' are. Do they? NO!... I'm not entirely sure I know what a right is. In my Windows Professional Certification course, we learn there are two kinds of rights: Logon rights and privileges... and I had thought that privileges were separate from rights.
> I'm pissed. I had 50 karma points and now I simply have "Excellent".
Yup, Me too.
Guess I might as well burn it all and start over.
*** Sigh***
Earlier today I was flopping back and forth between 50 and Excellent.
Now it looks like Excellent again.
I guess it doesn't really matter much but I would like to know what the new rules of the game are. (it is a game to me and I like playing- why take that away?)
.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
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"
> Earlier today I was flopping back and forth between 50 and Excellent.
Now it looks like Excellent again.
I didn't notice any flip-flopping on mine, but I just got on.
Right now I'm actually trying to burn karma (heaven forbid!) to find out what is below excellent. I bet everybody gets Excellent now - including the trolls. *** Sigh ***
Evil moderation is being used versus nice guys who noticed the new Karma crisis... We are lost, everything is lost.
Sigs are for morons... Wait a minute...
Comment removed based on user account deletion
Does anyone else think a Gauss gun, or similar EMP device would be the absolute shit for winning robot wars?
A 12" spinning blade ain't much use when the controller is dead, now is it?
terrorism! terrorism! T-E-R-R-O-R-I-S-M waaaauuuuugh let teh eagle soar! Sorry, Evil Bob. It was too funny to leave alone.
just slightly radical
http://obelix.cs.adelaide.edu.au/
"It is a greater offense to steal men's labor, than their clothes"
those disposable camera caps do pack a punch- i remember discovering them back in jr. high. my hand went numb on a partial charge and my friend got knocked on his ass, but we did rig up an effective stun gun...
here on my desk i have a capacitor that says "100UF-450VDC." Dont ask why. After reading through, i have come to the conclusion it is uber powerful. am i right? furthermore, what uber destructive things can i do with it?
Yeah, one time I got a bunch of disposable cameras from the photo shop for free for a project. They're a hell of a lot of fun to play with. You can charge the capacitor as if you were going to take a picture and then discharge it with . If you use something with a low conductivity (such as metal) it will make a satisfying pop with a little arc. Just don't use your body. I made that mistake once and it literally knocked me on my ass. (This capacitor is about 1/3 the size of an AA battery, if I remember correctly. Deceptively safe looking.) I never tried them as makeshift tazors, but the thought did cross my mind...
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.
It costs a whole lot for a portable camera. Even cheap ones are still around five bucks. However you can get those 100uF capacitors for 50 cents a pop. Why do it the hard and expensive way? The only cool thing about the cameras are their transformers which can take a small battery and give it 300V.
Fast Federal Court and I.T.C. updates
1. get a 5 farad capacitor, WHERE you say? TRAMS have em, they are huge.
2. charge up to 1 million volts...
3. surround the device with explosives like a nuke.
4. when charge is 100%, detinate...
5. result... large/fast discharge of electrons.
Eventually some unsuspecting person would wander down the hallway carrying books or something and as he passed the room the TA's would discharge all the capacitors, making a huge *BOOM* and watch the person leap into the air and throw their books all over the hallway.
Stop the Slashdot Effect! Don't read the articles!
Ahhhh!
I remember the days when I used to take those cameras apart to get the film and battery out and get zapped by the capacitor. My arm went numb the first time.
Later on we would purposly charge the capacitor and then throw pennies on them to watch the sparks fly.
Some of us even charged them and zapped others with them.
Them were the days....
"You're on my side and the dark side, like Lando Calrissian?" --Gimpy, Undergrads
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.
I have a .1F cap in my car so the lights don't dim when the bass hits.
How is it rubbish when it will weld a nail to a piece of metal? (Very fun, I suggest you try it sometime.) Maybe it won't work for his application, but that doesn't mean it won't work in mine. A chemical battery just doesn't respond fast enough. I suppose you could buy more batteries(maybe) or a special purpose battery but a cap is a valid solution, often a good one. Have you ever played with a car amp that needs 1000 watts?
Life is too short to proofread.
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?
Comment removed based on user account deletion
I never thought anything would make me sentimental for the good old comforting goatse.
YOU FUCKER.
I've known about these cameras for a long time. They simply are not worth it. You get one 300uF
330v capacitor. If you are clever you can find, for $5-$10, 2000uF 450V capacitors or similar at surplus stores. Granted, they are not photoflash capacitors. However, mine are still alive after being used to explode more than a hundred wires.
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.
Several years ago, I took a large pile of low-ish voltage electrolytics, strung them together, and made a 1 farad capacitor, just because it sounded cool. I actually used it, too, in-line with a home-built 12-volt solar panel, on field day. The system powered a 2m handy, with a 5/8s wave vertical stuck up 40 feet of pole. We were running QRP, and the caps actually did help, as the day was, at best, partly sunny - the panel kept dropping out when a cloud covered the sun, then I put the capacitor bank in-line.
Like the dumbfsck I am, though, I wanted to see how much current it held, so I burnt out the ammeter on my Fluke by shorting it across the power leads. To make matters even better, after blowing the fuse the first time, I wrapped it in foil and tried again. This time, the fuse held, but the Fluke was only marginally useful after that.
And people wonder why I got out of ham radio? *GRIN*
That's hands down the worst thing ever.
My friend is working with super-capacitors, it is a new thing, and they pack 4000f in really small case. btw. this is true. really! ah. noone will believe me anyway.
"A basic capacitor tutorial is probably in order." how about a basic gauss gun tutorial ?? i bet most of us know what capacitors are and i'd say 99/100 of those want to build one of these gauss thingies... :D
Who is this Karma guy and why is he bad ??
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
While it is true that one can find those 1 Farad caps which are only an inch or so in size, that doesn't mean that the huge caps are just weenie, they are often just very high voltage.
Three factors are important:
1) How many farads is it?
2) What voltage is it rated for?
3) What are it's physical specs (internal resistance, tolerances, operating temp, lifetime, linearity, etc)
So a 1 farad cap which can only take 3 volts is less 'powerful' than a 1000uF cap which can take 4000 volts. Then again, if you want a rapid discharge, the cap with the least internal resistance could have a large influence on peak current, and that again might be the big one. The drawback is size and cost.
As a side note, if you are charging them in parrallel, then they all have the same voltage across their terminals. If some are rated for lower voltages than the others, you can only charge up to the lowest spec. Unless you're wearing a flak jacket at least. Those dudes can explode.
Slashdot which is supposedly a bastion of civil liberties has taken action to hide information from it's user base for no apparent reason, and there is nowhere to discuss it... talk about FUD. We have to listen to story after story dissing microsoft for fud, well, Slashdot, youve shown yourself no better than them. Your only resource are your users and we won't take this crap.
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").
-- @rjamestaylor on Ello
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
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.....
If you're not an electrical engineer or trained technician with experience with such voltages, do not attempt this for yourself.
And reads...
Might wanna be careful where you put your fingers, mmmkay?
Perhaps now would be a good time for taco to lower the the time threshold on dormant account termination.
Ali
Ph33r m3!!!
This place [torontosurplus.com] has a great supply of large high-voltage oil-filled capacitors salvaged from all sorts of stuff.
Do they have good feul efficiency on them though? Don't want to spend too much on these suckers with gas prices rising.
Clever. I hope you die. Dammit, that was foul.
Writers imply. Readers infer.
./, wtf?
karma capped
Karma was the goal. Now it's a general indicator. I like it.
-- @rjamestaylor on Ello
this is exactly why Karma is now reported generally. This and the phenomenon of capped users complaining that they're dropped to 48 karma with a +5 post that is lowered 2 points afterward.
I didn't bitch much about that, more of making sure I stayed safely above 25 karma so as to keep my +1 Bonus of Kickassness!
Need help treating your acne? Come here!
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.
Have folks seen these yet?
http://www.cooperet.com/products_supercapacitors.a sp
Very interesting for low voltage applications. Wicked high capacitance ratings at very, very low ESR.
-Chris
--an unbreakable toy is useful for breaking other toys--
go figure, I post the link
http://www.cooperet.com/products_supercapacitors.a sp
and slashcode splits up the 'a' and the 'sp'. Damn open source hippies.
-Chris
--an unbreakable toy is useful for breaking other toys--
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.
Didn't notice. I on the other hand assume that most /.ers are using Mozilla (either Windows, Mac, Linux or *NIX version) with lovely tabbed browsing (to load random links in the background).
/.
If there is an optimal site for tabbed browsing it is
Karma/Schmarma.... who cares, post something interesting and relevant, otherwise get a life.
A fool throws a stone into a well and a thousand sages can not remove it.
Ive already that you ruled out car capacitors, and for good reason. I was wondering if the large capacitors inside microwaves or TV would work for you purpose?
No Beowulf cluster joke ?!
Capacitors can be very explosive, i have built some power supplys in the past and if you are not certian that you have the polarity correct then BOOM!!! you have paper & foil & oil all over the inside of your project, lol learning how NOT to do things....
I'm probably preaching to the choir, but if you've yet to begin construction of your bank, consider the following.
In the first large banks I built, I didn't give enough care and attention to load distribution inside the bank;result... most of the solder joints I painstakingly made were destroyed when it was discharged. Although there were 40 satisfying pop's as well as a nice green flash, I was aggravated to say the least!
My roommate in high school (NCSSM free public residential magnet school) built a rail gun with about 200 disposable camera capacitors for his senior project. He shot a 1 gram plastic bullet just over two centimeters. Amazing!
Some of the class A amplifiers (ie, not push-pull) include their quiescent power in the numbers on the box: 300W speakers! output 6W for each sattelite and 30W for the center channel.
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"
The capacitors in disposable cameras are great for use in tube audio circuits, which have DC voltages in excess of 100v. The capacitors usually sell for $1, $2 or more through parts outlets otherwise. A basic circuit can have several capacitors, so the savings are substantial.
It's very easy to modify the flash unit to be triggered by anything, for instance a motion detector or alarm switch, so you can add a pseudo-camera to an alarm system, for added scare-off factor.
You can create flash panels or bars that will slave off your camera's own flash.
Combine with LEGO Mindstorm to create a papparozzibot, for taking remote pix of dangerous celebrities.
Actually some car stereo have a switch mode power supply to boost up the voltage, so 12V is not a limit any more.
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?
Liar!
Even if you really do own a few car audio shops, you obviously sell crap, but I doubt you even own a single decent car amplifier. There are car amps that put out 1000watt RMS continous power. Go to a car audio competition. Or just buy a decent amp and hook up a current meter to it. If something draws even 15A at 12V it needs more power than 40 watts (and I'm talking about amplfifiers, not head units or wanna-be (walmart) amplifiers. You know nothing about amplifiers.
Any car audio amplifier has an internal power supply section that raises the 12V to some higher voltage, allowing it to put out more power than you claim.
Now about caps... An alternator does not put out perfect DC. Go read a little bit about electronmagnetic induction. You obviusly know less than I did when I was in 5th grade.
Maybe some kids buy caps, who don't need them but that doesn't mean they're worthless. Allow me to demonstrate: I have an amp right now that requires about 30A continuous power. Assuming this amp was 66.7% efficient that current draw is actually (assuming I was using it to produce a pure sinewave):
30 + 20 sin (wt) Amps
where w is the angular frequency and t is time (And ignoring the amplifier's internal power supply caps). That means that at at some times, that amplifier is drawing 50A. Let's assume I had a perfect voltage source in the front of my car.
I order to get the same level of power supply ripple (measured at the +12 terminal on the amplifier) I could either install wiring suited for 30A and a capactior, or install wiring suited for 50A.
Keep in mind that this analysis does not include the batteies internal resistance, the beneficial HF noise filtering properties of a capacitor, of the filtering of power supply ripple from the alternator.
Life is too short to proofread.
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
Dude, the Swiss are unbelievably well behaved compared to anybody, much less Americans. You could do surgery on the sidewalk there without causing an infection.
... you can buy 200 250V/120uF caps from digikey for around $1.15 per if you buy 200, or $2.15 in one-sy quantities. The time necessary to disassemble all the cameras is probably worth more than that to me (although I probably wouldn't have enough drive to build the gauss gun anyway).
Gauss Gun? C'mon, everyone knows the Gluon gun is way better. This guy must be a wallhack llama...
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, since the water vapor exerts about an atm of pressure on the inside of the can. However, if you submerge the can at this point in an ice bath, the vapor rapidly condenses and the can implodes by itself. Quite neat. You can make cans "jump" several feet once placed in the ice bath...
-----rhad
Slashdot needs to interview Natalie Portman.
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...
If you're working with high intensity UV sources (such as these flash units), wear an auto-darkening welding helmet and heavy clothing. UV burns are serious business and while they may only *seem* to cause temporary skin irritation and itchy eyes, the long-term effects are squamous cell skin cancer and cataracts.
Badness.
is made up of all the individuals of the state, not a specific army.
The state militia would call on all the residents, with the arms they have to defend the borders of that state.
This gun could easily be used to defend the borders of the state.
Why couldn't it help in the maintenance of a militia?
And you only need one camera.. go into a pitch black room, let you eyes adjust. Charge up the flash and let 'er rip.
You are instantly teleported into a monochromatic world where time is frozen and you can do cool things like read the text off a spinning fan blade.
I worked on triggering systems for pulsed eximer lasers in the late 70's for a small outfit in Needham, Mass.
So, here goes:
1. We used ceramic caps we called hockey pucks. They were rated at about 40KV and whatever (I forget) uF. We built banks of them, two in series, with about 40 or so in parallel, bus barred together. Pricey, but it packed a punch. This was conducted to a flash board inside the laser cavity which was 'pumped' with high voltage electricity. Hence, pumped eximer laser. Since we could recharge them fairly quickly (on the order of a second or so) they were pulsed at a decent rate. Also, we could "tune" the frequency of the laser by using different gases in the laser cavity. CO2, argon, you get the drift.
2. Dangerous stuff, kiddies. We had to submerge some of the bigger banks in a container of oil for several reasons, like problems on humid days because of the high voltage or just plain shorting out across the caps.
3. Switching that kind of power is done by powerlabs using an expensive SCR. We used an interesting trick. Picture a thick hollow plastic cylinder about 7'' across and maybe 2'' high. The circuit was connected to plates on the cylinder ends. The cylinder was filled with a gas and there was an ordinary automobile sparkplug in it. When the plug was fired by a separate circuit (similar to an ordinary auto coil) the gas was ionized and the switch 'turned on' and dumped the cap bank's charge into the laser cavity.
So, the system seems similar to what we are seeing here. Only more dangerous. I took a few hits from testing the triggering systems, but that wasn't anything like the hit from the full cap bank. I never heard of an accident with the big KV caps, but we were all VERY respectful of the power. It may have proven fatal.
4. So, to sum up: KV caps arent toys, but they can be fun. Ours were shipped wired to prevent accidental charging. They are like guns, only more dangerous because the dont *look* dangerous. Also, in humid weather, they can be somewhat unpredictable. The 'ion switch' trick bears watching, its a good cheap answer to the problem of switching large high voltage currents in a real hurry.
5. BE CAREFUL!!
So, I guess the kid in the article was using 330 V 120uf caps. They can pack a punch, but the Kv is the way to go for real speed. Would switched automobile coils give the power needed? Or just do a bunch of caps in series and power them up with a switch coil?
--too lazy to create an account...
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.
I have a pickup truck load of old capacitors I stripped from 3 old Burroughs B700's and B730's I got for free from a bank.
They are the size of those big fat beer cans.
You can charge one on a car battery and lay a screwdriver on the terminals and it will burn the screwdriver in two.
I want to play with exploding water and other such fun things. Maybe a railgun too.
OTOH, you can build caps in 5 gallon buckets for bigger fun, charge them with Tesla coils..
Hmmmmmm.....
Over a couple of years I collected hundreds of these. I had all the Mini-labs in the city center collecting them for me and four stores in the suburbs. I couldn't collect them from Kodak stores as Kodak would recycle the cameras. I have a page on the subject, as well as some links.
Collecting Disposable Flash Cameras for Parts
I have recieved a few shocks when carelessly taking the cameras apart.
Some of the developers told me they sometimes have recieved a shock when removing the film from the cameras.
Remember to discharge the capacitor.
The capactitors can be soldered into a square with 10 rows and 10 columns on a PCB to give about 800J. The voltage can be left at 300V or wired in series for a higher voltage. 100 of these capacitors give a good size bang when shorted. The stores these days have an incentive to keep the cameras, they can recieve goodies like Leathermans depending how many they send off to be recycled.
I did recieve a good supply of batteries for my Metz flash, LCD, Radio and for friends while I collected the cameras.
FYI, there are violent crimes in Switzerland. Not that many, but they are there. In 2001, there were about 160 offenses involving the death of the victim (murder, manslaughter etc). Half of them were committed with firearms. Practically nobody uses a selective-fire assault rifle for a planned crime, since it is too large, heavy and cumbersome, not to mention LOUD and not exactly easy to hide.
As for prison sentences, well, I'd be very surprised if anyone got a longer prison sentence for a crime in Switzerland than in the US. Swiss law forsees much shorter prison terms across the whole spectrum of crimes than does American law (as do most European legal systems) and judges tend to give out laughably short sentences for all but the most serious crimes. The only crimes for which a life sentence is possible are murder, mass-kidnapping [terrorist style] and genocide.
The political left has long been pushing to abolish the tradition, though a parliamentary subcommittee recently voted down a proposal that would have kept the weapons at barracks.
Swiss gun law is a little bureaucratic (as is pretty much everything in Switzerland...) but liberal by European comparison. The requirements to get a WES, a one-time certificate that allows you to purchase up to three fire arms (that can be issued as many times as you like, as there are no limits as to how many firearms you are allowed to own, nor how much ammunition):
1. 18 years of age
2. Swiss citizen or resident with a class C residency permit (others need permission from their nation's embassy)
3. No serious criminal offences on record
4. No illnesses that make weapon misuse particularly likely, such as alcoholism, heroin addiction or paranoid schizophrenia
Provided you meet those requirements, the WES (Waffenerwerbschein) is practically guaranteed (if you don't get it despite meeting the criteria, you can challenge the decision in court). There is no license, the WES is only required for purchasing, not possessing a firearm. Firearms can be confiscated if misuse is considered likely, IE if you threaten somebody, or if you are, for example, diagnosed with a some kind of severe mental illness. Permanent confiscation requires that you are compensated, even if the confiscation is as a result of a prison sentence, unless the weapons themselves were used in the crime.
Carrying weapons is another thing entirely. You are allowed to carry a weapon in your home or business with further ado, and licensed hunters can carry a gun while hunting as well. But carrying a gun (concealed or not) for other purposes requires a permit which is *difficult* to get. Apart from the WES requirements, you also need to have reason to carry a weapon, which is defined in the weapons code as being to protect yourself, somebody else or an object and to pass a theoretical (gun and related laws) and practical (target shooting) test. The reason requirement, while it sounds fairly open, is in practice fufilled only by those who are at especially high risk. AFAIK, people should, if they can demonstrate that they are reasonably responsible and are capable of handling a firearm, be allowed to carry firearms in public. (which they were in many cantons, before this firearm law came into power). Apparently, concealed carry, though illegal without a license, is quite common amoung youth, for whatever reasons.
It's worth noting that practically every other country in Europe requires you to demonstrate a necessity in order to merely own a firearm.
by Robert E Iannini (1983)
Books In Print shows two active records:
ISBN 0-8306-0604-1
ISBN 0-07-156069-6
I have this book (somewhere) and it has all kinds of interesting projects/plans, including a 20mW CO2 laser, and a 6MW(!) pulse generator - I don't recall the duration of the 6MW pulse, so I can't tell you the joule output, but it's enough to explosively vaporize any Radio Shack component of your choice...
"Time is an abstract concept devised by carbon-based lifeforms to monitor their ongoing decay." - Thundercleese
Really? They really sell capacitors that are supposed to smooth out the transients at the input of the power amplifier? P. T. Barnum was right! OTOH, I once created an "L" filter using a coil and a capacitor because the alternator whine was so annoying.
You draw more current @ 12V. Duh. It's okay not to understand EE. Just don't act like you do.
Life is too short to proofread.
Yes, folks, the code really does look that bad.
But it appears that "Excellent" is anywhere above 25.
There is a capacitor gun in Legacy of Herot by Larry Niven Jerry Pornelle and Steven Barnes
If voting could change the system, it would be illegal. - God used to be my co-pilot, then we crashed into a mountain
Why is it every story here there is some asshat whinging about people soending their own free time on projects other than Linux?
Boobies never hurt anyone. - Sherry Glaser.
If you live in the USA, then read up on exactly what BATF does and does not regulate. You are in the clear, unless your local community has their own restricitons.
I do not deploy Linux. Ever.
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"
This guy gives new meaning the the phrase "Point, click and shoot."
Chew: You Nexus, huh? I design your eyes.
Roy: Chew, if only you could see what I've seen with your eyes.
(subj)
We had a shop class where we worked on cars and such, and took the condensers off the old motors to charge them up. (they have just one wire with the case being the othor conductor) Then we would put them in some girl's locker. A charged up condenser will make a spark almost a 1/2 inch long when the wire is discharged to the case. These girls didn't have a clue and start screwing around with it. Invariably they would be holding the case when they got around to touching the end of the wire. BAM! Condensers will hold a charge for quite a while, so whenever we saw one around, you would discharge it before picking it up and messing around with it.
Needless to say, all the girls in the grades around us now know what a condenser is.
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 you want to see a powerfull gauss gun in action or make one, go to:
PowerLabs Gauss Gun Research.
The video of projectile perforating a can with speed of 240km/h is here:
coilgun.mpg
it's called an inverter you twit. you're obviosuly not an EE...maybe you've taken physics 1 in high school, but you are no EE
--fetch daddy's blue fright wig, i must be handsome when i release my rage
Just an idea for how to discharge...
Wouldn't a hefty switch work? I know that peak currents would probably be lower because of the formation of the arc (have to have the reed(?) move FAST!) and you will probably fry any electronic device within a couple meter because of the emmisions, but it could handle it.
When I say hefty, I mean something like a hefty screwdriver or crowbar (i know you'll be collecting all you life and get it to 1 or 2 MA) attached to a large spring, manually triggered.
###/
/ O-----
/
/
"/" = screwdriver
"#" = spring
"o-" = contact and wire (contact should probably be replaceable...heheh)
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
Please be careful with this stuff folks. The defibrillator you will find in a hospital emergency room will deliver from 20 to 400 joules in about 2 to 20 ms. It can suddenly stop you heart or restart it. During the 1970's I was a "biomedical equipment tech" and had to periodically test these things with a specified non-inductive load resistor network and an oscilloscope. You can be sure I was VERY careful.
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!
Some industrial strength inverters (AC/AC) for induction motors use an inner DC-link (at a few kilovolts). Storing something like 40 MJ (Yes, fourthy megajuoles) ..
Now there's some energy to release
-- Sig (appended to the end of comments you post, 120 chars)
Hey! I just read that book about three weeks ago. I guess I subliminally stole the idea from them. Rats! Grendels!
Keep in mind that 1uf is equal to 10 to the minus 6 farads. C must be expressed in farads for this formula. I calculated .6534 joules for the flash capacitor,and 0.000002 joules for the audio capacitor.
The audio capacitor is hardly worth the effort at any cost.
Dude, up the meds. Or at least do a little physics and then take a pill. Unless you've got a nuke to provide power you're not going to bring down an airliner. Ever heard of something called lightning? Way more power impule than you'll ever generate. The worst you'll do is put a little fuzz into someones cell phone call.
A rail gun can make a gauss gun look like a TOY.
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
I'm concidering taking Electrical Engineering in College next year. I havn't had acess to many electronics in my youth, so I havn't had much experience with picking things apart and experimenting. My father is a basic Electrician, and has a number of basic electronics books lying around, do you think these would be a good start for someone beginning to take an interest? I'm mainly interested in robotics. Once I know what I'm doing, maybe I can look into working with these Cameras, and try to make them useful. Any info is higjly appreciated, hope to see some of your articles soon, thanks.
I meant more power than all other man made electrical power at the time. I didn't mean to imply that I was comparing Watts to Joules.
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!
You're totally missing something up there.
Isn't waitng for a response to your post much less satisfying that just _reading_ the article? And where would we get big bags of clues?
Sony will include DRM/EMP+ in their Pain Station 3. Sony will coorperate by providing EVD players, EVD is for Extended Violence and Death to those daring to violate licenses, or Enhanced Video Display for those complying by inserting their Visa card in their player prior to media insertion.
Phillips officials would only say, 'These certainly won't qualify for the CD logo.'
Florida Corrections Department officials have announced their support of the devices, noting that it could save the state millions in state funded police staff, trials and executions. State coroners did object indicating this could create a horrendous backlog. Disney lobbyists were overheard saying to John Ashcruft, "Is any measure too much in the war to defend Bambi from these un-American terrorist media pirates!".
Chinese electronics trade association representatives have commented that, now that they control the means of electronics production, they can liberate the west of such corporate insanity, if consumer demand is sufficient.
On related news front, Microsoft announced a major contribution to the unix community, in cooperation with the BSA, by providing 'ClosedBSD .NET EMP/DRM+' beta CDs with Bioguard mice. The kits will be mailed to everyone subscribing to SourceForge, magazines where Linux is advertised or discussed, and any MSN address where a non IE browser was used to access Hotmail. Users will be advised to upgrade, or face being banned from the Internet. Microsoft indicated the CDs include an upgrade path from Linux. The Bioguard mice use DNA sampling to authenticate users to the Global Authenticated Internet. This is the minor adjustment to internet administration which Homeland Security office representatives explain as the natural outgrowth of intergovernmental efforts to remove all the hiding places for terrorist pirates. "No more anonymous, illegitimate identities will be allowed! We all must live in the sunshine, above board, living lives in an open book, with all our electronic neighbors logged and monitored, as all civilized peoples expect and demand." The 3 remaining global broadband ISP providers (Cable East and Cable West, and Global Satellite, Inc.) all will turn on the GAI simultaneously July 4th, 2003 and we'll all celebrate our independence from terrorists around the world.'
1) I fixed it about an hour after I broke it (before your comment was posted). Thanks for the vote of confidence though.
2) See http://slashdot.org/~CmdrTaco/journal/9748
and 3) this thread is clearly offtopic :)
Interesting.
I never have brought my scope out and measured the voltage that my amp(Boss REV-1035starts clipping at.
Maybe I'll go do that at lunch today.
It's rated 250 RMS @ 4 ohms into two channels @ 0.01% THD, but I think that spec is a little generous. It is possible given the amp's 40A fuse but it would need to be 87% efficient, which I doubt.
Anybody else have any real rms vs. manufacturer rated RMS measurements they've done?
Life is too short to proofread.
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!