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Build Your Own Tesla Coil 287

screenbert writes "Ever wanted to keep stray dogs or neighbors from trampling your backyard, but just couldn't find the system to really deter them? Well this site shows how they built a bi-polar Tesla Coil system. I've always loved the Tesla coils on C&C when they'd zap the units as they went by. "
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Build Your Own Tesla Coil

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  • by Dystopium ( 255143 ) on Thursday August 08, 2002 @10:52PM (#4037191)
    I need one of those to keep my roommates off my leftovers in the fridge.
  • And I thought watching a bug zapper was entertaining!
  • Make yourself a Pedestrian Electro-Bastard Array!
  • by Alizarin Erythrosin ( 457981 ) on Thursday August 08, 2002 @10:58PM (#4037217)
    How to have fun in a computer lab #14:
    Two words: Tesla Coil
  • envy!!!! (Score:3, Funny)

    by Emugamer ( 143719 ) on Thursday August 08, 2002 @10:59PM (#4037227) Homepage Journal
    Any other pyros out there really really envious right now? I'm about to turn traitor any second. Matches just do not compare
  • by yeoua ( 86835 ) on Thursday August 08, 2002 @11:01PM (#4037236)
    That's actually a picture of his server after this story was posted.
  • The test was only performed at sixty percent of full power since full power (40 kilowatts) wasn't available at this location. The system is actually capable of discharges of aproximately forty feet

    I can see this causing brown outs if you do this in the local small town. Complete with stories of UFOs etc.

    Musn't upset the town fathers.

  • Erm.. (Score:3, Insightful)

    by Anonymous Coward on Thursday August 08, 2002 @11:04PM (#4037249)
    Not to nitpick, but the aforementioned site doesn't exactly show how they built the Coil, just that they did, and how it looks in operation. It's an old site, too; built in '96. I'm fairly confident this isn't news; although a decent schematic certainly would put this at "Stuff that matters."

    That having been said, Google cache []

    • I saw what was billed as "the world's largest Tesla coil" at the Survival Research Laboratories show [] in Austin in 1997. The Tesla coil [] was the only cool part of the show...they had flourescent lights stacked around the thing [], so the coil could arc and hit them and light them up. I thought it was cooler when the Tesla coil just arced up into nothing [] in the air.

      The rest of the show sucked, however. The "Hand of God" promptly ran into a ditch and stayed there. They had an extremely tasteless mockup of the U.T. Tower, complete with murderer at the top, to which they set fire. They had some sort of walking robot, which didn't walk very well. If it wasn't for the Tesla coil, I would have felt very ripped off.

  • "Hey everybody! Watch this!"

    Egads. I guess these are the guys who always ignored the "don't try this at home" warnings, huh?

  • by Darth Paul ( 447243 ) on Thursday August 08, 2002 @11:07PM (#4037256)
    Palpatine: And now, young Skywalker, you will die!
    (Palpatine begins rubbing feet on carpet vigorously)

    That picture of the "Man of Great Potential" is really giving me strange ideas.

  • The control system and power transformer together tip the scales at roughly three thousand pounds.
    Makes this a little difficult on the mobility side, but hey, with one of these [], the world is your playground (or you'll just be really lonely)
  • Be careful! (Score:5, Funny)

    by Glowing Fish ( 155236 ) on Thursday August 08, 2002 @11:13PM (#4037289) Homepage

    Before Slashdot posts stories like this, they should very expressly warn their readers about the dangers inherent in such projects. Although a simple Tesla Coil is not particularly dangerous, if a Tesla Coil is turned into a mobius strip and enough energy is put into it, a electrotemporal-topological disaster can result, plunging an area up to 5 kilometers around it into Dirac Space.

    You can find more information about this strange and dangerous phenomenea here [].

    • Before Slashdot posts stories like this, they should very expressly warn their readers about the dangers inherent in such projects.

      They did, they said the guy was "bi-polar".
    • Re:Be careful! (Score:2, Interesting)

      by coryboehne ( 244614 )
      I would like a further description of the mobius strip, and an explanation of wtf a electrotemporaltopological disaster is,,, I'm sorry for my ignorance in this area, but I have a need to know.... After all I might want to make one of these .. J/K... But if this is so dangerous and easy to build why hasn't some country produced one and vaporized (or electrotemporaltopologicaly destroyed) some city?
      • Beause often this device also causes ontological collapse, causing the very Being-as-such of the destroyed areas to return to an essential, rather than an existential being. Now, normally, being and essence are two seperate things, and since to destroy one would be to destroy the other, Being-as-occupying in the way a city does can not be destroyed totally, and so even as one side is wiped out, the other can not be, so the city reasserts its ontological identity.

        Now, some people would believe that memory is just data reflected in a synapse. But really, memory is a process where the ontological throwingness-of-being of Beings is reassertted in the personal ego by reconciling somethings Being-as-such with its Being-towards-others. Butif identity and being are crossed, as they are in a Mobius Strip, they can be linked together, and thus annilated from the memory of Being-as-being-towards-its-own-reconcilation at once.

        So lots of cities have been destroyed with this weapon, we just don't remember them.

  • does someone have a mirror of the movie they had on their site or did the just remember to remove the movie before the onslaught of slashdotters
  • I'd watch out. All those geek chicks that would be flocking to your door for building such a contraption might end up being shocked, and have to stay away.

    I'd leave it off by default, and just flip the switch every time some kid wants to sell me cookies. Hah!

  • by Xtraneous ( 594376 ) <> on Thursday August 08, 2002 @11:25PM (#4037332)
    Did anyone else notice that if you click on one of the three pictures at the bottom of the pages, it brings up a new page with that image? Try clicking on segments of that image... Interesting way to have an online photo-album. Seriously, has anyone else determined what relevence the colors have to the pictures, and where you click versus what type of image you get?
  • Nothing says "a mad scientist lives here" quite like having one of these [] running.

  • If you like liked this artice, you'll love : ;-)

  • You could avoid being hurt by the (insert really big number here) volt potential difference by wearing a coad of chicken wire. The charge collects on the outside, keeping you safe on the inside. (No, it doesn't need to be grounded, and I know it's called SHIELDING.) Just be sure to ground it before you step out though, or you could get a very *shocking* experience.
  • that's what it looks like when i beat off in front of my computer for two hours at internet pr0n.......... :)
  • These devices aern't as cool as I had heard of. I was half-way through building one of these things when I realized it wouldn't skeletonize anybody that came within 10 meters.
  • Look here, and at the links within:

  • what is C&C (Score:3, Funny)

    by Anonymous Coward on Thursday August 08, 2002 @11:53PM (#4037428)
    C&C Music Factory? What?

  • Now This guy [] seems to understand Tesla coils nicely, in fact he is trying to build a 100kva Tesla coil [] for his next show (he does his thing at Burning Man festivals) , check out the movies

    i swear he's mad,
    but mad

  • As a tesla coiler... (Score:5, Informative)

    by muon1183 ( 587316 ) <muon1183@ g m a i l .com> on Friday August 09, 2002 @12:46AM (#4037557) Homepage
    As somebody who has built several tesla coils, I though I might be able to provide some information on this topic. A tesla coil is basically a high frequency transformer. They come in two varieties, traditional and solid state. A schematic for a traditional tesla coil can be found here []. The main for a traditional tesla coil is usually a neon sign transformer, or NST as we call them. The capacitor is often a milspec jet engine ignition capacitor or a leyden jar made out of beer bottles. Solid state tesla coils are similar, except they use a less powerfull main transformer and use a flyback transformer (found on most tv's, although flyback's from the 50's and 60's work best, as they don't have as many safety devices) as the resonator. Just be forewarned, the information on the site I linked to is about 5 years out of date.
  • by Cyno01 ( 573917 ) <> on Friday August 09, 2002 @12:51AM (#4037571) Homepage
    i take no credit for this, this is from UPL18, written by Jolly Spamhead, In this article I'll show you how to make a very effective modem killer weapon, especially on crossbar phone systems (CPS). I take no responsiblity whatsoever if you kill yourself or get hurt in an attempt at trying to do this fucked up trick or for some reason it just doesn't work anymore as I haven't performed it since early 1998. A great person once said it is never too late to pass infomation on wit the show bitch! What the fuck is this strange device? It's a Tesla Coil! Concentrated static electricity you f00l! The Tesla coil when properly used will generate litrally thousands of volts at very low amps. That just happens to be the right current to bake silicon chip cookies over a open camp fire strumming Bodycount songs! Construction: 1. Disconnect all phones from your line. Disconnect answering machines and any data-transmission devices. 2. Run a test on the coil and disconnect nearby grounded objects. (Lamps, stereos, TV's, Sex Vibrators...) 3. Connect one phone that you would'nt mind maybe having to sacrifice for the act of revenge.(It usually doesn't destroy phones, but people have told me they have seen them melt off walls!). =) 4. Connect iron or steel balls to the green and red wires of your connected phone (aka the biege box wires that go on the clips.) It and 12 terminals of your phone. 5. Put on a pair of thick rubber gloves (EXTREMELY IMPORTANT STEP HERE!) 6. Charge the coil to at least 10,000 volts. An ideal setting is around 18 to 19 thousand, but 10,000 will jump Ma-Bells line surge protectors and that's what we are trying to do here. 7. Hold metal balls in your left hand. In your right hand hold your cock and proceed to stroke firmly until climax is reached, then lick up the mess! Just fucking around here again! =) Just Make sure the balls don't touch each other ok? Great! When the coil is fully charged, clip the steel ball connected to the red wire to the base of the Tesla coil and hold the other metal ball as far away from the coil as you can. 8. Dial the offending modems phone number (OCI's fax # would be nice). 9. When you are connected, move the metal object connected to the green wire within 2 feet of the coils top. Don't be afraid of the little bolts of electricity shooting from the top of the coil...its only the stuff that hits poor hopeless saps like Amit Grover AKA Foreskin boy every once and awhile. 10. Within 3-5 seconds a huge bolt of lightning will shoot forth at the phone from the hand you are holding the balls in. Hold on tight cause it will feel like a load of ants! You will immediatly hear many strange occilations to the carrier on the phone. The last noise you will hear from the phone is a pop! That is the last cry of agony as the modem shuts down This is guaranteed to fry the modem, the computer and any peripherals connected to it like Scanners, printers, 8-ball porn cams.
  • by Christopher Thomas ( 11717 ) on Friday August 09, 2002 @01:12AM (#4037620)
    I've wanted to build a Tesla coil for years.

    The reason I still haven't is that they're about as good for electronics and magnetically sensitive media as a lightning strike. The intermittent arc gives off *vast* amounts of RF crud, which will induce currents in just about anything electronic and degauss anything magnetic nearby.

    Your computer case will not save you if your machine has drive bays. All connected wires (modem, network, power) will also act perfectly well as antennas penetrating the case's shielding.

    Credit cards and bank cards generally aren't shielded at all :).

    Set up those Faraday cages before building anything like this.
  • Finnaly someone showed this to the public. It really is an old idea, but in the world we live now, it has some interesting effects. I was tracing the development of such toys based on Nikola Tesla's ideas for a while now and found a lot of impresive stuff. Just do a quick search on "telsa weapon" and read some of the articles that pop up. One of the most scary is located at[2345].html [] (yeah thats five parts of it). Hints about causing earthquakes with similiar technology as described in the story above. Other interesting sites are Gravity gate [], Kelly BBS [], Tesla web ring and similiar. If you like to search a lot, you may even find hints about top secret super high tech weapons developed in Russia for knocking out satelites, which are also based on one of the Tesla's ideas and are powered by also originaly Tesla's work, improved by dr. H. Moray, the so called Moray generator. Basicaly you just set up an antenna and some electronic wizardry and you have electricity. Sounds too good to be true, but there's a story on the kellynet about how Tesla made an electric car powered by such a device.

    Back to the EMP stuff...does anyone have some nice information about project HAARP and similiar "experiments" all around the world? I heard somewhere that US military already developed their small EMP "bomb" for knocking out "e-criminals". I would like to take a look at one of those toys :) And the next thing would be to cover my house entirely in somekind of conductive mesh, to make more or less effective faradey cage. I feel like protecting computers and other electronic equipment will be big bussiness in the next decades.
  • I've wanted to build one of these things for at least 8 years now, but have never had a) the time, b) the knowledge, c) the motivation. Especially after reading (parts of) Winn Schwarau's "Information Warfare" doorstop, I could just see the potential uses for this. Imagine one of these scenarios:

    You're driving down the highway, blissfully ignorant of the speed limit. Suddenly, you see those blue and red lights flashing behind you. Panic? You? Nah. You hit that extra button below the rear defroster, and suddenly you're in the clear. Or better yet, you let yourself get pulled over, and then while waiting to ask if there's a problem, the other car starts acting funny...

    From the book: Someone in a van drives around the computing center of a bank. Hits a button. Computers start to drool. Wait a random amount of time, do it again.

    Your (former) employer doesn't believe that they need to worry about information warfare because "the firewall will protect us." Wait for the night before a drop, or the day of a demo, and suddenly the development machines, not to mention the firewall, are dead.

    As much as I'd love to have plans for one of these HERF guns, I think that it would probably make it too easy for "hardware script kiddies" to then go out and wreak havoc. What I'd really like is a reading list (preferably with difficulty ratings) on what to study to be able to design your own.

  • by MillionthMonkey ( 240664 ) on Friday August 09, 2002 @02:41AM (#4037803)
    You can easily make a Tesla coil if you have an old busted TV to rip apart. In general, the older and bigger the TV is, the better. And color TVs are better than black and white. This won't be a *great* Tesla coil, but it will throw a spark a few inches long and you can do all the standard Tesla coil tricks with it (St. Elmo's fire, etc.) without investing too much time or money.

    Yank the flyback transformer out of the TV, and discard all its primary windings. Keep the big high voltage secondary winding (the one with the zillions of turns). It's usually encased in rubber and may look like a big rubber wheel. Its main lead has really thick insulation and connects to the side of the picture tube (where it looks like a stethoscope). The other lead (the ground) won't be as heavily insulated.

    The only other parts you need are two NPN power transistors (2N3055), two 5W power resistors (20 ohm and 200 ohm), some wire, and a good supply of DC current (12-24 V). The circuit is a piece of cake. The first time I did it, I put the whole thing together with alligator clips.

    This circuit has two primary windings around the flyback transformer core. The power winding is 8 turns, with a tap in the middle. The feedback winding is smaller (4 turns), also with a tap in the middle. The power winding leads connect to the collector leads on the transistors, with the center tap going to the +24 V DC power source. The feedback winding leads connect to the gate leads, with the center tap there going to +2-3 V DC (connect the resistors in series across the DC power to get the lower voltage in between). The emitter leads are grounded.
    As current flows through one transistor, the changing field in the core induces a voltage in the feedback windings that turns that transistor off and the other one on. Then current flows the other way, and the same thing happens in reverse. So the circuit tunes itself to the proper frequency. But it also means that the first time you power it up you run a 50-50 chance of connecting the leads to the wrong transistor gates, in which case you get a stable DC circuit. So if it doesn't work the first time, try exchanging the gate leads.

    This circuit is fairly well known, and doing a Google search for "flyback" and "Tesla" I found a schematic [] for it right away. The guy mentions on that page that the transistors get really hot and he is not kidding- they do. Don't leave it running for more than a minute without a heat sink. The RF noise generated by Tesla coils is incredible so expect to generate some interference. They make lots of smelly ozone. And if you let a spark go through paper, you can start a fire so be careful.

    If you're lucky you can get 20-30 kV, which throws a purple spark a couple inches. (I only got about 4 kV out of mine- the spark was about a half inch long.) Pick up a neon bulb when you're at Radio Shack- these light up if they're around. The effect on a candle flame is interesting. Don't stick your bare finger near it because the spark does hurt if it hits unprotected skin. But if you hold a metal object and use that to touch it, you don't feel a thing (it's high frequency AC). Cool tricks include having sparks jump from the coil to a metal object in your hand, having sparks jump from a metal object in your other hand to ground (even a lousy ground), and having fluorescent tubes glow softly if you hold them in your other hand. If you touch one terminal of a fluorescent to ground then it will glow brightly between that end and the place you are holding it, like there are Orcs nearby.

    • modern flybacks use a integrated diode. If you can find a old tube tv you will have more fun. You mentioned burning through paper. I remember burning through a penny.
      • Where in the heck can a guy get a good transformer today? You're right about the diode and also, the "flyback" transformers that are in modern TV's and monitors have like 10 or more pins that I can't find any docs for...

        Which led me to looking for a source of FBTs, thinking that I could buy a new one and it might have a spec sheet with pinouts or that I could find some spec sheets on line. No dice. Which leads us back to my original question.

        Please don't say, "Wind your own!"

        Vortran out
    • Did you check out the pictures in that schematic link? One of them has him with a charged rod that looks something like a lightsaber (he's standing on a plastic trash can so he doesn't get fried). The captions say to make sure to remove your watch, yet the guy in the picture is wearing his. Oh the irony. I suppose he's still alive though.
  • In those pics where the arcs are coming off of his fingers, he looks like a sith lord! Lucas could use this and save a lot in special effects! Plus it's REAL, well, excep the pain....
  • (Score:5, Informative)

    by Archon-X ( 264195 ) on Friday August 09, 2002 @04:02AM (#4037919)
    I'm always wary of these sites. They show all this electricity zapping round, and guys with electrofingers.

    Only problem is this: Unless a tesla coil is specifically built for this purpose, the skin effect does not work on telsa coils. You actually cook your organs.

    I think it's highly irresponsible to blaze things like tesla coils.

    I've built one, I've used one, and had an enjoyable time, but safety must be the first priority, not pretty pictures.

    For more information about the dangers of tesla coils, Here [][Chip Atkinson's Safety sheets]
  • by hydrino ( 131216 ) on Friday August 09, 2002 @07:13AM (#4038169)
    I built a medium sized Tesla coil for a school project. I put it in my car the night before and someone moron my complex parked next to me and thought it was a bomb.
    I was awoken by a phone call from the police at 1AM with no less than 4 police cars and 3 firetrucks in my condo development. They actually were trying to shield nearby condos from an explosion with the firetrucks. The bomb squad was being dispached.
    I had to leave my condo in only my boxer shorts and give an oral report on how a Tesla coil works.
    I cover it with a blanket now when I move it.
  • See powerlabs, []. Amazing hi-power electrical and other interesting stuff.
  • Ever wanted to keep stray dogs or neighbors from trampling your backyard, but just couldn't find the system to really deter them? Well this site shows how they built a bi-polar Tesla Coil system

    Ofcourse it depends on how the Tesla Coil is feeling at that moment. It might see the dog and think "oh, i won't bother zapping it, life sucks!". On the other hand, it may have a manic episode and send out little zaps to make the dog dance! (Dance Doggie! Do the Hustle!)
  • That's not a Tesla coil, he just living inside one of those Van De Graaff generator-globes
  • by afflatus_com ( 121694 ) on Friday August 09, 2002 @10:49AM (#4039308) Homepage
    If you are interested in the picture on the website, here is an additional photograph of Tesla himself in the same pose, only his coil is giant-sized, and the arcs fill a warehouse. He is sitting reading a book under the giant coil with the million-volt sparks fly overhead.

    Note that for this photo to work, it had to be reexposed several times for all the lightning forks to be catptured (and he sat at the end).

    Picture of Tesla under his giant active coil []

    The noise genereated from the coil in the photo could be heard 10 miles away.
  • ... just let me turn on a light in my cube for you....ZAP !

    Ooops. So you don't want to enter my cube and run your narcware on my computer?

    Have a nice day.

One can't proceed from the informal to the formal by formal means.