this is a very cheap mini tesla coil made of stuff i had lying around.
how it works: "Electricity flows into C1 until a high voltage is seen across G1. When this voltage is high enough, a spark jumps across the gap and allows C1 to discharge into L1 and L2. The voltage "bounces" back and forth at an extremely high rate. When the rate of discharge between C1 and L1 matches the rate of C1 and L2, the two circuits are said to be "in resonance" and the voltage goes up through the roof."

DANGER HIGH VOLTAGE: although the amps are relatively "low" this can still be dangerous. always turn it off before making adjustments unless you are experienced. I TAKE NO RESPONSIBILITY IF YOU GET HURT!
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Step 1: You will need...

a 9.5in x .9in (od) PVC pipe 
15 high voltage capacitors 
matching round head bolts
a bottle
2 pens
electrical tape
speaker wire
about 300ft of 32 awg mag wire
18 awg solid core hook up wire

hot glue gun
different drill bits 

power source:
flyback driver or

Step 2: Secondary

Picture of secondary
this will take a lot of time do do but is pretty easy. all you have to do is wrap the 28 awg wire around the PVC pipe until there is about an inch of space left on each side held in place with tape. the way i did mine: i put 3 nails into my desk, one i put the role of wire on, the other two i used to keep tension on the wire so i could use both hands to hold the pipe, it took me about 1/2 an hour to finish.
dogucan978 days ago

I'm really new to these stuff and this is the first electrical thing that I'm making except the simple battery-wire-lightbulb circuit. I see two grounding parts in the diagram. How do I do those? How do I ground them? Also, what should I use as "Trm1"? Lastly, what is that "s.g."? I think the spark gap with the screws in the wood is "g1".

pkaa2 months ago

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what was the total cost for building this
considering doing this with my science club
but we have VERY limited funds
Jimmy Proton (author)  parker davis1 year ago
The only thing I payed for was the magnet wire, you can get it somewhat cheap
how did you remove the diode from the dc flyback transformer...plz explain
ty in advance
wdrake11 year ago
Is this the proper wire to use for this step?
wdrake11 year ago
Hi, I am looking into building this with my science club. I just want to know- In the parts list it says "300ft of 32 awg mag wire, but in step 2, it mentions 28 awg wire. is there a difference? thanks
Jimmy Proton (author)  wdrake11 year ago
Oh sorry, didn't notice that, 32 awg is thinner, use 28.
how much does it cause? Are 15 year boys enough?
Electrodude2 years ago
can you use electrolytic capacitors?
Jimmy Proton (author)  Electrodude2 years ago
No. electrolytic caps dont have very high voltage ratings so you would need a lot, plus this is AC, electrolytes are DC
Bumba Lodh2 years ago
Hi,I built a TESLA COIL with 5kv 30ma nst.Primary coil made with 4mm
copper tube with 10 turns secondary made with 2inch PVC pipe.Winding
height 10.2inch(0.315mm enameled copper wire used) also made Capacitor
bank with 2kv 0.15uF polyester film capacitor.But the problem is my
Capacitor burnt several times but the coil works with LEYDEN JAR
capacitor.Why the capacitor burning??????

Please Help Me!!!!!!!!!!!!!!!
Jimmy Proton (author)  Bumba Lodh2 years ago
well if you're using a 5kv nst and your capacitors are only 2kv, the problem is kind of obvious. (assuming you're using 50Hz) the exact resonate frequency of your transformer would be 0.019uF, you can achieve that by just putting 8 caps in series, this will also increase your voltage rating to 10kV, so they shouldn't burn out unless you're using bad caps.
i tried to put 5 capacitor in series to increase the voltage rating to 10KV and also tried put 8 in series but every time i get the same result should i use polypropylene film capacitor?
Jimmy Proton (author)  Bumba Lodh2 years ago
Yeah you should try a different kind of capacitor, im not sure what kind but polypropylene film caps should work fine, just dont get cheap ones!

aweis3 years ago
so how about 70 volts alternating current, a kila volt that is one thousand volts right?
Jimmy Proton (author)  aweis3 years ago
70V is way to low, for this one you need at least 1kV, the supply I was using was about 2kV.
yes but 1kv is after the transformer, that increases the voltage, when really your power source was likely the 110-120 volts of a house outlet unless your the European 220. so instead of 120 how about 70v before the transformer is what i was asking. wich i know is entirely possible now. just not as powerful.
well it depends on your transformers output.... thats all that matters

hii !!! i have secondary on a 2.5 inch PVC and my toroid is made of aluminum duct . now i want to know whether there is any electrical connection between these 2 . how should i mount the toroid on the secondary ??

Jimmy Proton (author)  sudhanshu5293 years ago
You connect the wire on the end of the secondary to the toroid and mount it on top of the pipe, make sure there is no metal in the pipe though.
so i have to connect one end of the secondary to the toroid ? what about the other end ??
Jimmy Proton (author)  sudhanshu5293 years ago
The other end goes to ground, but I didn't do anything with it on this one, just left it there.
i plan on making a smaller one than this, besides people can get several hundred thousand from standard wall outlet, 120 volts, and i intend to have a high voltage transformer, which you seem to be not using, i will not use a flyback transformer, because f expense, are not those for makeing direct curent into alternating current? i plan on making many of my own capaciters, and where can anyone get a 1kv power supply without breaking the bank, all i need is a tesla coil to produce tiny sparks, the generator alone can produce a quarter of a centimerter sparks already, so a smal tesla coil made well enough could probably get me something visable, it is my first tesl coil, and all i need is it to be at least 6 inches tall, and produce some sort of electrical discharge. do expect everyone to make the exact same one as you?
Jimmy Proton (author)  aweis3 years ago
Still, even 100V is to low for that, 500V is more of what you need, maybe more. You can use an electronic lamp ballast probably, the one I have is 580V and I use it to power my 100kV flyback. I have herd that you will probably get AC output from a DC input from a flyback which is the only explanation why I can use a flyback to power this. By this way, this is poorly made Tesla Coil and creates very small
and as well i intend to make mine better improve it ad a toroid, to increase spark production experiment with making bigger sparks, and also something such as a neon sign transformer make it quite a bit more powerful from standard house electricity, with something like that does it have to be standard socket power to power the neon sign transformer. something funny just happened that i had to put in here, i misspelled something and when i used spellcheck one of the suggestions was "typo"
wait electonic lamp ballast is that used in some way to produce enough electricity, to power the capaciters, wich actually where the power is converted into hiugh voltages from, so i would technically be able to make a small maybe 6 inch tesla coil work, it is just the wind up for the electrical discharge may take a while the first time and have more space inbetween,
and bytheway what does a flyback driver look like? any websites to help me see images&examples would be greatly appreciated !
search google images for flyback drivers
For the 15 high voltage capacitors, I will need 15 of them? and what does it look like?
R.A.T.M2 years ago
you do realize that the wire wrapping is wrong its not the wright amount its 2 much more your power source the point of the coils it to increase the voltage and get a ark that dosent need a direct ground yo put arks
sguy12 years ago
i am working on teslacoil. and i don't get one thing! which of the wire positive or negative from capacitors joins the spark gap? is it negative? if so what to do with the positive wire from capacitor?
what about grounding ? is it primary coil or secondary coil or capacitor to be grounded?
and what are the things that we people be careful of while making this stuff.
Jimmy Proton (author)  sguy12 years ago
There is no polarity is this, it is AC, the bottom of the secondary is grounded and just dont touch anything and you'll be fine, although I would say that the streamers are safe to touch for something as small as this.
oh so you mean that we can join any of two wires from capacitor!!
Jimmy Proton (author)  sguy12 years ago
what if we don't include capacitor? will it still work?
Jimmy Proton (author)  sguy12 years ago
thanx for the replying soon. keep making these cools stuffs.
instead of a flyback or NST, would i be able to use a marx generator power supply to run this?
Jimmy Proton (author)  lightning r fun3 years ago
i dont see why not, all you really need is a continuous AC power supply

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