Step 5: Disclaimer

Picture of Disclaimer
The circuits in this Instructable use very high voltages and currents.

These currents and voltages are deadly! You can easily hurt yourself, as well. Build this circuit at your own risk.

This type of high frequency high voltage current is used in surgical cauterizers. So if you get shocked you will burn yourself and cut your flesh. There is also a considerable fire hazard from the circuit.

Use the Nikolai Tesla's safety techniques when working with high voltages:

1. Only use one hand (put your other hand on your lap or pocket)
2. Wear insulating shoes
3. Use a dead man stick or insulated pliers when touching or manipulating the circuit.
4. Use a power bar with a thermal fuse rather than sticking the circuit directly in the socket. This will limit the current that will go through your body.
5. When soldering, disconnect the circuit from the power outlet.

Generally, in electricity it is the the current that kills. if the currents are low there is little danger even if the voltages are very high (think of Tesla holding the his Tesla coil).

This circuit has high currents which makes it considerably dangerous.

a 65W CFL can deliver 65mA easily (65W/1000v).

And if you look at the picture below, at greater than 50mA the little guy is dead.
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setinight6 years ago
How do you find the diode to disconnect it for AC use?
Biotele (author)  setinight6 years ago
Good question. The diode is buried in the plastic casing. You can try to hack it off, but you might ruin the flyback. I suggesting googling looking for somebody who tried it. The easiest thing is to buy an old B/W TV, the flyback back then was seperate from the diode. Or just look on ebay for old flyback. Please inform me about your results.
I did some searching but no luck in finding how to remove the diode, from what I found it was suggested that it's easier to just find an older flyback without the diode

well there is always the possibility of using, and old automotive induction coil. but you would not need a cfl for that. just about a two amp, 12 volt, around 500hz to 1kz square wave or pulse generator.

setinight6 years ago
I tried using the CFL circuit on a microwave transformer, but didn't get squat. Is there a way to use your circuit to make it work on a MOT? (By the way, I got it to work great on a TV flyback, but I'm still trying to find a way to get ac output. Taking out the diode is not going to work and hard to find old TV without it)
Biotele (author)  setinight6 years ago
the MOT has too much impedance it is designed to operate at 60HZ. My suggestion is to try to fry the built-in in diode in order that it conduct ac. I never tried it, but maybe someone has, so google it.
Thanks for your info. Actually, what I am trying to do, is build a poor-man's heat induction coil. I was trying to use your CFL circuit towards that end, but may be a dead end. Any ideas or suggestions along that line??
Biotele (author)  setinight6 years ago
You don't need a flyback for that! Just make a flat pancake coil and hook it directly to the CLF. Put a capacitor in parallel with the coil to make into a resonant tank. The pancake coil will resonate and will heat inductively anything in the vicinity. You will need to experiment with the number of turns and capacitor values for the optimal set up.
Cool, sounds a lot easier than what I was trying with the flyback. Will that work as well with the coil coiled into a tube instead of a flat pancake? I want to heat up rod shapes with it. Thanks!

yes you, can use copper tubing for that. since you are going to need to run coolant through the copper tube. and it takes a while to learn how to design, any induction coil so that the field does not cancel itself. but they are not limited, to shape. but depending upon the thickness of the rods, you want to heat. i am, not sure if even 65 watts is enough. unless they, are small rods.

Mansheep225 years ago
I've found that new CFL's are incorporating more advanced circuit-detecting abilities, and are harder to fool into thinking a bulb is attached. Also, I am unable to get nearly the same voltage other people are getting (probably just under 1,000v DC at 1.7mA), and am going to try to wire two or more flyback transformers in line, to keep amping up the voltage. Will I die in a fiery explosion if I attempt this? Thanks

never a good idea, to exceed the design specifications of any fly-back boost transformer. might be smarter, to try the other transformer first. plus you might try, checking the open circuit voltage of the cfl device. at 1.7 watts, it may not be operating correctly. when it sounds more, like you are operating on the filament tap winding only.

Biotele (author)  Mansheep225 years ago
can you post a picture of the circuit?
i want to build cockroach electronic trap from 9v dc 200mA out put votage 4.5 kv where can i get circuit ? pl help ...

from a comercial bug zapper.

handyman295 years ago
Is it 50mA or 50MA, because I don't think 0.05A is enough to kill someone. I would think 5A is enough to cause damage. I've worked with wires connected to 500mA sources and I am still here.

Well, when you think that earlier, they used to toy with frog legs and electrostatic electricity which was enough to make the muscles of the legs react... think that a rather steady 50mA will do to your heart...

If electricity goes from one place on your hand to another place on the same hand, you'll probably not die... but it'll nonetheless hurt and burn...

Also think that thermal power is UI... 50mA with 10000V => 500W... better not have that dissipated through your body...

You still think that 50mA is too low ?

BTW, 500mA sources can deliver AT MOST 500mA... this don't mean that when these low voltage sources are connected to you there will be 500mA going through you... When you "short" a 9V battery with your finger, you don't empty it quickly...

the idea is to avoid, either high current or high voltage. and most especially the chances of it going thru, the heart.

when you, have worked with electronics or electricity as long as i have. we've all most likely had, our mishaps over the years. but have been fortunate, to have survived them. but it is no assurance, we will be as fortunate tomorrow.

at low amps, or 60hz, the danger is stoppage of the heart. at high amperage, is the danger of being cooked to death, or life threating burns and infections.

and i seriously doubt, you are going to short a 9v batter with your finger without seriously special conditions. using your tongue yes, giving you with an acid taste in your mouth. but it is still not a short circuit, and a way you can test batteries for their charge with experience. but would not try that in, a light socket.

under normal conditions, the human body will not conduct dc from 2000 v to 100,000 v. so most of the static discharges, from your finger are over 2000 v. but once the high resistance skin is punctured, it takes less voltage to bridge the gap. one spark or more from and induction coil, with a piece of paper can verify this effect. it will leave, a small hole.

never use your left hand, keep it in your pocket. your chances of survival increase, if it does not go through your heart. even using your left hand, can go through the heart through your left leg. or from your left to your right hand, through your heart.

but remember, in a short circuit or decrease in resistance voltage decreases as current in increases. once current, begins to flow. if you are not using, a constant current device. so 50ma or 500ma does not necessarily diminish, the current danger. though the wattage, will generally not greatly exceed the capability of the electronics. so many high voltage circuits, are capable of producing the sure death 1/10 of an amp or more. 0.1 amps x 500v = 50w; as 20,000v at 2.5ma = 50w. so never assume you cannot, reach that always fatal 0.1A current through the heart.

and when even wearing high voltage, gloves and boots. high voltage, can find it's way through the slightest pinhole. and even a high voltage corona, or capacitive discharge, can knock you for a loop even if properly separated from a ground.

corona discharges are cool, if you know how to do them right. turn off the lights and watch, the pretty tentacles dance in air. and can even make a balanced wire spin, on a point contact post. or light up, burnt out fluorescent and neon bulbs using the ac version.

but i, do not suggest a plasma cannon. those glowing balls of plasma, can be a real shocker. if you want to use the focus and deflection coils from a tv to fire a plasma discharge.

so you know there is a lot more cool stuff to do, than just a Jacobs ladder.


Many of the comments here are complete baloney: almost nobody has even a basic grasp of Ohms Law.

What kills is CURRENT: and all those stupid 'sayings' from old electricians are worthless folk-lore.

It takes only 50mA to kill you, but the catch is to actually get 50mA flowing - trickier than it sounds. This is why the World is awash with anecdotes from people who have been shocked by vast voltages or from supplies capable of hundreds of AMPS yet lived to tell another cliché.

Electric current doesn't make your muscles twitch, it causes nerve fibres to fire randomly. This WILL make your muscles twitch a bit, but the main effect is to desynchronise the complex signalling to the heart, which therefore goes into VF and you die. Usually quickly.

But the only way you can get enough current through the body is to overcome skin resistance, which is often megohms. So a big voltage will sometimes do it, but not necessarily. Often, big voltages have big internal resistance, ( like a car ignition ) so the supply doesn't have the balls for it and all you get is a shock.

If, OTOH, your skin is sweaty, or you're standing in a bucket of porridge, even a low voltage supply will easily pass through. There are reports of a man killed by 12V because he was soaked in sea-water ( not verified this, but the idea isn't so far-fetched ). And, if the current flows from one arm to the other ( straight across the heart ) you're really asking for it.

One more thing: your body is mostly like a capacitor, not a resistor. So, AC is much more deadly than DC ( all those sayings by old electricians to the contrary are therefore WRONG ) and, for complex biochemical reasons, low frequency AC ( like 50-60Hz) is more deadly than higher frequencies. Oh, dear!

a tenth of an amp through the heart, is always fatal. above or below this, chances of survival increase. but current tends to increase, as voltage decreases in a short or very low resistance circuit. so it is possible to receive, a tenth of an amp through the heart at even at 50miliamp high voltage output. however 60 hz, even down to 30 milliamps, may cause the heart to fibulae.

how ever above 1/10 of an amp, the toaster oven effect becomes the greater danger. flash burns from 2300v 1100 amp service or higher, can kill you without direct contact. even flash burns from 440 v at 50 amp service, won't do you much good either.

but the fact remains, with any voltage or current. you cannot afford to relax safety standards. as 6v is the lowest known voltage, to cause death. and until you get above 250khz, the danger of burning flesh is too great. tesla coils at uhf, or shf frequencies, most likely won't harm anyone. but i, would not make a practice of this. but then i am, a lot older and wiser now not young curious and naïve. it is not the number of times, your got away with it but the one time you don't.

maddog1014 years ago
Hey can somebody help me with how to get the flyback transformer off the circuit board of the CRTmonitor? i don't know if i should break the circuit board or what i should do. can somebody please help me!?
OW! MY EARS HURT FROM ALL THE YELLING! Seriously, there's no real reason to capitalize an entire paragraph.
Biotele (author)  maddog1014 years ago
Break the board with a pair of pliers. Wear gloves and safety glasses.
OVERLOADED3 years ago
comodore6 years ago
Hes not Nikolai Tesla, hes Nikola, NIKOLA, please correct that mistake! Thank you!
-max- comodore5 years ago
i think "Nikolai" and "Nikola" are spelled both ways...
comodore -max-5 years ago
nope, believe me....I am from Serbia so I know for sure !
brady9115 years ago
I finally got mine to work, BUT, it only produced about 5Kv. Anyone know what a source to the problem could be?
brady9115 years ago
I cant figure out the Pins on my Flyback. i did what the instructable said but it didn't work
Biotele (author)  brady9115 years ago
Take two heavily insulated wire with alligator clips at each end and try every combination of pins possible, one at a time. Turn off the circuit every time you change the alligator clips configuration (very important).

THANKS! but i think this one is shot. so im ordering a new one. I think it was a bad one anyways. the test with the Volt/Ohm meter didn't get a result. but if i cant find it that way ill try every possible combination

Got it to work! Awesome. I was starting to doubt my ability. But a larger CFL, some experimentation, and some time later.. And I got a cool purple arc between a pair of nails. Next, get a couple of rods and finish up the project with a Jacob's ladder. Thanks for the great instructable. And the advice.
Biotele (author)  Dirtie Hippie5 years ago
can you post a picture of you setup? that will be cool. Thanks.
firehand76 years ago
Neat idea! I have been designing industrial electronics for many! years. I cannot emphasize enough that ALL projects using AC mains (110v or 220v) should be isolated from the power line. Isolation transformers are inexpensive and can save your life. They eliminate the path to ground.
I LOVE THIS Instructable! I plan on using the power supply for making a Cold Plasma Device. I LOVE those things to. Once I finish building it, if it works, I might write an instructable about it. P.S. thanks for writing this, I needed a power sup. +30KV and I couldn't figure out how to do it myself. This stuff REALLY scares my parents. I'll have to build it outside(they don't understand that Cold Plasma is completely harmless).
Biotele (author)  ColdPlasmaDevice6 years ago
I made this instructable especially for people like you that need an easy to build HV supply. Enjoy and looking forward to your Instrutable.
joinaqd Biotele6 years ago
can you tell me how much current a photoflash capacitor has?i dont have a volt meter..
quite high. high enough to give me the expression of the little man no3 up there- about 10-15 mA. it won't kill, but you get a quite painful shock. it dosen't involve sparks, its just like a weird hot, burning sensation, but when i looked at my fingers they weren't burnt
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