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Build Your Own Tesla Coil
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.
"
I need one of those to keep my roommates off my leftovers in the fridge.
Every college student knows that to keep your roommates from your food, you just poisen some of it, after the first couple of them die, the rest learn pretty quick. It may not be high tech but it gets the job done.
How to have fun in a computer lab #14:
Two words: Tesla Coil
There are only 10 kinds of people in this world... those who understand binary and those who don't
That's actually a picture of his server after this story was posted.
That picture of the "Man of Great Potential" is really giving me strange ideas.
I believe you are incorrect. You're talking about the Telsa "Earthquake machine" oscillator, which was a tunable steam- or electrically-powered weight. There's a book about it, IIRC it's called the "Tesla Earthquake Machine" or something like that, and includes plans to build your very own.
Tesla, upon inventing the oscillator, attached it to a bar of the finest steel he could get, and within a few minutes the oscillator had found (been set to?) the resonating frequency of the bar and shattered it. Tesla then attached it to a pillar that was driven into the earth at his laboratory [keep in mind that his lab, and several other New York buildings, were built on a patch of sand, IIRC] and turned it on. He took a crowbar to it when the buildings across the street started to shake.
Keep in mind this device was no bigger than a 2-liter pop bottle, if I rember correctly.
The Tesla Coil is a high-frequency, high-voltage transformer, and shares few parts or concepts with the "earthquake machine."
This
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 .
Hopefully I didn't put any [] around my words.
Where did you ever hear that?
Seriously, Tesla coils really were always about arcing electricity. His original idea for Tesla coil usage was wireless transportation of electricity. Basically, if you crank the volts enough, you can arc across the atlantic ocean. At least that was the idea.
Yes, Tesla also did some studies on structural harmonics. And yes, he did the structural harmonics work long before he came up with the idea for Tesla coils, but aside from being the brainchild of the same man, the two were never linked in any other way.
Also, I must say that I more enjoyed his work on structural harmonics. Shaking bridges and collapsing condemned buildings was all well and good, but the nutball had the idea that he could crack the earth in half if he used enough dynamite and timed it correctly. Good thing he didn't have the resources to try that one out. Tesla was crazy enough try it, just to see if it would work.
My father found an old Popular Electronics (or something) magazine from his hobby days with some plans. We hand wound the voltage stepup coil, made condensors out of perspex plates and tinfoil, and borrowed a Ruhmkorff Induction Coil from school.
The unit was powered by a car battery and could spark about an inch and a half.
We put two bent copper rods for the spark to jump between. The spark would run up and down between these rods like old mad-scientist movies.
It felt pretty cool to put a finger in the spark and watch it jump straight through, with only a weird tingling sensation.
Aaah the electric shocks, the smell of ozone, the burns and blisters - God I miss science fairs.
So, this is a great idea, and a cute trial.. but you're never going to get a tesla coil that can really injure people
Yeah, but I bet it will keep the neighbor's cat from pissing in my flowerbed.
-- If god wanted me to have a sig, he'd have given me a sense of humor.
I would like to politely remind you that resistance causes a voltage drop but no change in current :) You could concievably suck up all 100ma and be in ALOT of pain :)
Religion is a gateway psychosis. -- Dave Foley
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.
There's no sig like SIGSEG
i take no credit for this, this is from UPL18, written by Jolly Spamhead, http://phonelosers.net 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...so 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.
"Sic Semper Tyrannosaurus Rex."
One hopes that the above poster is intentionally posting pseudoscientific nonsense... but a few people seem to have taken it seriously... so...
.1 Amp. That will stop someone's heart.
While these Tesla coils are probably harmless, to do damage to a human you need not 100 amps, but less than
Furthermore, let us say that you want to put 100 amps into something from 20 meters. First of all, 10,000 volts isn't anywhere close (you calculations are way off - in fact, they are sheer nonsense!) A few megavolts at a minimum would be required.
But... as far as power delivered to the load... the resistance of the air is uninteresting. Once the arc starts, the resistance drops dramatically in the plasma. Thus one could deliver 100 amps at 20 meters with a lot less power than you calculate.
The statement that electricity naturally flows to the nearest earth is likewise fallacious. Electricity flows (or tries to flow) across potential differences. If you hook one end of a potential difference to the earth, electricity from the other end will certainly try to flow there. But if the Tesla coil is insulated from the earth, the electricity will have no particular interest in flowing to the earth!
All in all... very cleverly stated nonsense.
Naughty of you (or ignorant of you).
The only good weather is bad weather.
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.
Hm.
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]