loading

A slayer exciter is basically a small solid state tesla coil, usually a one transistor design. The circuitry for it is simple. One of the first things anyone who has built a joule thief will notice, is that the circuitry is very similar. The biggest difference is that the small transformer or inductor has been replaced with a primary/secondary tesla coil configuration, and that the feedback is capacitively coupled. (There is a good abount of capacitance between the 'top' of the coil, and ground.)

There are many awesome thing these exciters can do!
they can:

WIRELESSLY Light up:

  • neon lights!-----------------------------------------(several feet away)
  • florescent tubes!----------------------------------(within about a foot)
  • CFL's!-----------------------------------------------(within about a foot)
  • EL wire---------------(it does not work well for me. If anyone tries it, please tell me your results!)
  • LED's!-----------------------------------------------(across the room if done right)
  • and even small incandescent lights! -------(with an L3 coil)
  • paper with pencil markings -------------------(before it catches fire!)

Burn and ignite:

  • candles
  • wood (pencils)
  • human flesh (now my fingers smell burnt)
  • paper

Destroy:

  • crappy / half dead LED's
  • bacteria
  • sensitive electronic equipment (phones, computers, SD cards, CD's, blu rays, flash drives)
  • someone else's stuff

Create:

  • ion wind motors
  • the coolest lantern or light on earth
  • fires
  • plasma cutter


►Make following electronic equipment go crazy:

  • calculators
  • watches
  • digital clocks and alarms
  • devices with capacitive touchscreens (PlayStation VIVA, smartphones, feature phones, tablets)
  • UHF remotes


Transmit wacky sounds (loads of EMI) to:

  • AM radio
  • FM radio
  • shortwave radio
  • HAM radios possibly
  • TV interference

Here is how to make a my version of the more powerful exciter (These videos were made awhile after this intructable, so the only issue with it is thermal management.)Please do not get the instructions in this video confused with the instructions for the later TO-92 one in the further steps. Different bias resistor values should be used for either of these 2 versons.

Step 1: A rundown of my experimentation

I did modify the circuit a LOT before I was happy with the results. Sadly, I did not take pictures of my circuit on the breadboard.

  • The first picture show first circuit. I could not get to work.
  • The second picture shows my first working design. I chewed through many transistors, and it was not very stable, but it worked.
  • In hopes for better performance and reliably, I tried a darlington pair. It put out about the same amount of power, but did not kill my transistors. I believe this is because it increased the gain and the feedback from L2 was enough to sustain the oscillation. I think this is because it did not latch up and pop my transistors.
  • I realized after running the circuit for awhile that I wired it wrong on my breadboard but it worked anyway. I decided to "fix" it, and ended up burning out my last 4401. From then on I had to resort to 2n3904's. This darlington pair test was inconclusive due to my mistake of not having the collector from the first transistor connected to anything. I learned that if it ain't broke, don't fix it :P
  • I finally decided to revert to my original circuit, except this time with all 3 remaining 2N3904's all in parallel. (collector to collector, base to base, emitter to emitter.) This worked exceptionally well, and I haven't killed any transistors since then! Now, I even get plasma shooting out the end! If you decide to build this, use that configuration, but use more powerful transistors, like 2N2222's or 2N4401's. They can handle more current.
  • [UPDATE, March 2014] Later on I then decided to use a MJE3055 transistor instead of the weak TO92 transistors, and started to get much better performance. I upped the voltage from 9V to 12V, and replaced the 1Mohm resistor for a 10K resistor. You can get the instructional details in the video.
  • [UPDATE May, 2015] I have now began work on a MOSFET version of the slayer exciter, and with 50V and a computer heatsink, I can achieve results that border a small SSTC!!! (Solid State Tesla Coil) Unfortunately the complexity of the circuit did increase, due to the need to drive the gate of the FET with buffer to allow fast switching. Luckily it is ultra stable when tuned correctly, and can deliver much more power with more supply voltage. I increased the size of the heatsink compared to what I used in the first slayer exciter video, and have active cooling fan giving some airflow. Now I can let it run indefinitely at 24V and beyond! :D Note: The topload is still critical, if it is too large, performance will decrease. Also I can draw up to 3 inch long, incredibly hot arcs, and get corona that is about an inch long!!! I have even managed to "burn out" a screwdriver from the inside-out! Where the shaft is encapsulated in clear plastic, the plastic began to experience dielectric breakdown and began to melt, and eventually the electricity burned a carbonized hole all the way through the plastic to my fingers, Ouch! The electricity must really love me! :P.
<p>Hi Max.</p><p>I have been fighting with that project for over 30h. My slayer exciter works, however not as good as yours does. I have filmed it to show it to my friend: </p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/0JSM9veJ6ec" width="500"></iframe></p><p>My stuff:</p><p>-12V DC power supply</p><p>-10kOhm resistor</p><p>-3x100nF ceramic capacitor in parallel</p><p>-MJE3055T transistor </p><p>-940 turns of 0.32mm thick wire</p><p>-aaaaaand... I tried 4 or 3 turns of 1mm thick wire, 3 turns of 1.29mm thick but there I can't see any change,</p><p>When I put 5kOhm insted of 10kOhm it is barely better. I have tried changing the top load (from 100mm diameter styrofoam sphere coated aluminum foil to one hard drive disc) but it doesn't work. I decided to take a look at primary coil. I tried to put it higher or lower on the secondary. Put it closer and further. Put the turns close and far of each other BUT it doesn't work.</p><p>Here are some photos:</p><p>http://imgur.com/a/PcJXv</p><p>Can it be that thin wire on the beginning that make the efficiency so poor? On the primary there's also a connection, but I checked it and it doesn't drop the voltage of the battery that I tested.</p><p>Pleace help me.</p>
This circuit took me weeks to perfect. It's hard to tune due to the chaotic nature of its operation. Take a look at my last few steps for troubleshooting.
<p>Thx for responding. I'll try to optimize it.</p>
<p>Hi there -max-, I have a quick question, I have a solid state tesla coil here, (capable of playing music) and was looking at increasing the arc length by changing the physical properties of the primary or secondary coil. I run it at 32V and can get up to around the 48 range but then the mosfets tend to start to fail and higher standard mosfets start to get expensive! So what attributes of the coil affect the arc length and the &quot;clarity&quot; of the sounds it can play, if you happen to know. </p><p>So do any of these change the arc length:</p><p>-secondary diameter</p><p>-secondary height</p><p>-secondary height to diameter ratio</p><p>-number of secondary turns</p><p>-Toroid size and type (my current toroid is just some 12awg tin plated copper wire wound into a spring and then curved to make a toroid) I know most coils use a solid toroid or a diy aluminium duct toroid like yours, which looks fantastic!</p><p>-number of primary turns</p><p>Also do you know how tesla coils like the onetesla oneteslaTS can get such long arcs? I don't see how they can get such long arcs without burning something out. I use 1.2KV 10A mosfets whereas the onetesla uses 650V 120A IGBT's, is that the difference? the number of amps and setup?</p><p>Any help at all would greatly help me</p><p>Thanks</p>
<p><a href="http://www.richieburnett.co.uk/tesla.shtml" rel="nofollow">http://www.richieburnett.co.uk/tesla.shtml</a></p><p>Here, I think this link may contain lots of good documentation on SSTC design and construction. (the website design leaves a lot to be desired and looks pretty mature, but the content is good!) These high voltage high power RF circuits are mysterious. As you will no doubt learn, layout is critical, and RF snubber networks are important to protect the MOSFETs. You do not need particularly big MOSFETs, in fact he used a full bridge design with IRF750 MOSFETs and was able to make like 8 inch steamers with that.</p><p>To eliminate hiss, he built a small tesla coil that operates at 4MHz, he calls it a hfsstc, or High Frequency Solid State Tesla Coil. It is a very unique design, and uses a few class E amplifiers to achieve high efficiency ZVS switching. The biggest problem with operating high power transistors at such frequencies is that the transistor will spend most of it's time switching on or off as the gate takes time to charge and discharge. The beauty of the class E amplifier is that, like the ZVS driver for flyback transformers, the transistors are switched only when the voltage across the drain and source is close to zero, so very little power is wasted while the transistor changes state. Learn more about what he did here: <a href="http://www.richieburnett.co.uk/hfsstc.html" rel="nofollow">http://www.richieburnett.co.uk/hfsstc.html</a></p><p>Here he wrote at the bottom for future developments:</p><blockquote>The stable nature of the corona at these high frequencies make the HF-SSTC an ideal candidate for audio modulation. Audio modulation of any Solid State Tesla Coil is possible by varying the RF output power in sympathy with an incoming audio signal. This varying power causes the air around the spark to vary in temperature and expand and contract producing sound waved. Sound produced in this way is fairly high quality because there is no inertia and there are no resonances caused by moving parts. But there is usually a large amount of background hiss due to the corona itself. This tends to detract from the quality of the music. However, by increasing the operating frequency up into the Megahertz range the corona becomes much more stable and the hissing disappears. This allows for high quality audio modulation with minimal distortion or background noise.</blockquote>
<p>Hi there, thanks for the reply (sorry I didn't see it until recently because it didn't appear in my inbox for some reason!) this really helps me with my tesla coil adventures. I've already started making some improvements based on your advice I very much appreciate your detailed response. I also have another question which I posted on your youtube video &quot;Weekend Projects: How to Make a Powerful Slayer Exciter Tesla Coil&quot; via yt account &quot;ZBCuber&quot;, regarding a weird occurrence in another slayer exciter I made which is baffling me.</p>
I am really not an expert at these SSTC circuits, so I can't give you much help on how the secondary coil needs to be shaped or constructed, But I am reworking my flyback driver circuit and how I can achieve arcs about 3 to 5 inches long playing music even clearer than my computer speakers! (particularly better clarity at the higher end. This is because plasma arcs have no mass and can create higher frequency pressure waves without the requirement to oscillate a massive diaphragm and overcome inertia.) The only limiting factor is the drive frequency of the flyback. It is oscillated at about 20HKz to 30KHz because this is close to its resonant frequency and achieves the most impressive arcs per unit input voltage. You can think of this frequency the sample rate. (it is still not HiFi, which is often 44.1KHz, 96KHz or even as high as 192KHz) And the general rule of thumb in audio applications is to have the sample frequency at least 5 times higher than the highest frequency &quot;note&quot; to be played with clarity.<br> <br> -----------------------------------------------------------<br> <br> That said, if you want better music quality, I found that long, thin, stable arcs are the best, at least for my audio modulated flyback driver. Have a corona breakout point will need to a lot of audible hiss in the sound. Similar to cassette tapes. hiss like that does not bother me too much when listening to music but it is worth noting.<br> <br> ------------------------------------------------------------<br> <br> <br> The actual sound quality itself is going to mostly depend on how you implement audio modulation. My latest LM339 based flyback driver drives the flyback transformer in the flyback mode of operation rather than the resonant mode of operation. By modulating the duty cycle of the transistor gate drive, I can&nbsp;affects the flyback energy stored in the magnetic core and ultimately delivered to the secondary. Larger duty cycles (up to a point) allow greater current to build up in the primary and greater magnetic flux to be stored in the core, which results in more current in the secondary and consequently&nbsp;thicker sparks, which heats the air more, which finally makes the air it expand away from the arc more than thinner arcs!<br> <br> ----------------------------------------------------------<br> <br> So the question is how are you audio modulating your circuit? What circuit are you using? Schematics? The easy technique often used for simple circuits like mine is to simply modulate the DC power rail in one way or another. This is basically Amplitude Modulation, or AM. Yes, the same AM as AM radios. It will sound fine as long as the carrier frequency is &gt;&gt; 22000 Hz. This does exactly the same thing, it modulates the power delivered to the high voltage discharge and creates sound.<br> <br> Another classic way to audio modulate SSTCs is to use frequency modulation, or FM. Taking the transformer out of resonance in response to audio once again affects how much power is delivered on the output spark.<br> <br> ===============================================<br> <br> If you hear heavy clipping and distortion in the audio when an arc is established, then you may be have too much gain in a amplifier stage and the output is saturating. For my flyback driver, this would be equivalent to the audio signal causing the duty cycle to try to fall below 0% or above ~60%. The only solution would be to reduce the volume. Yeah, audio modulation is not the loudest, I know. Longer arcs will result in louder audio and better frequency response (more base).<br> <br> ---------------------------------------------------------------<br> <br> If it sounds muffled or cruddy, (particularly if you are modulating the power supply voltage to achieve audio modulation) then you may need to remove filtering capacitors, whose job is to eliminate voltage variations (in this case, voltage variation due to audio). Similarly with any of the other techniques, it means that you need to make sure you did not make a low pass filter of any sort by accident on the audio input stage.<br> <br> Well I know that was a LOT, so I hope it helped!
<p>how is it that you ain't feel a shock? how big does my resistance need to be, at 18 volt. Ohh... and I heard that I should use lots of turns for the best effect, but what's the diameter and the lengt of your pipe?</p>
<p>There are a lot of things at play and several reasons why I am not getting Hurt. Firstly, while the circuit can generate huge voltages on the topload, it cannot maintain that voltage when loaded down. Even if I touch the top load, the voltage will quickly fall because it cannot deliver much current. It can be modeled as an ideal AC voltage source with a very large resistor in series with it. The more current you pull, the lower the voltage becomes. By the time the spark jumps through the air, it &quot;loses&quot; its voltage, and is only a few hundred volts or less by the time it penetrates your skin. The skin effect is a strange one, basically stating that the higher the AC frequency is, the less the current will penetrate into the conductor. At really high frequencies, the current will mostly ride along the surface of any conductor rather than through it. This is why litz wire is used for RF applications.</p>
<p>how is it that you ain't feel a shock? how big does my resistance need to be, at 18 volt,</p>
<p>great dude... very informative</p>
<p>yeah im def gonna build that, just gotta get wife to let me use cc to order those drop ins, just wanna have a working slayer circuit in meantime to check my old psu against he new one (and these are cheaper lol)i'll just stick with what works then in meantime then. thanks mate :)</p>
<p>Hey Max, rebuilding my slayer circuit cos theres a short in it somewhere and i broke one of the transistors legs off (lol doh) but i was thinking of grabbing a couple of these 2N3055 NPN transistors in the meantime so i have something working again to test the new power supply - the slayer circuit has developed a mysterious short some where and nearly blew my old psu as well, and rather than mess around im thinking rebuild, im wondering if more powerful transistors are worth trying, considering im going to feed it more voltage? threy're cheaper too:) would need higher voltage cap too,but i have some already so thats ok, hook up is nice and easy with those too. though would probably need a different bias resistor, would i need to go up or down there from 1K? im thinking probably up? also have some signal diodes to try out too. sorry bout all the questions, i have got myself some paired transistors from the other thread re: totem pole so its all happening albeit painfully slowly (very little spare time atm - 2yr old and 4 yr old keep me fairly busy!)</p>
If you want more power then I was able to achieve in mine, then consider building my tesla coil SSTC, utilizing a MOSFET and a DS0026, and a 48V power supply.<br><br>IN honesty the classic slayer exciter circuit is not designed for high power and is a pretty crappy design. It is not efficient, and BJT transistors are not the best suited for switching applications.
<p>Okay so now my model looks the same as yours but it's just not giving more arcs.</p><p>Secondary coil - 30AWG - 800 turns</p><p>Primary Coil - 16AWG - 2-5 Turns(reduced or increased within this range according to the supply)</p><p>Transistor - MJE3055T, TIP3055, TIP31C (Tried everything)</p><p>Supply - (9-27)V</p><p>Resistor - 10K ohm... Tried 1M ohm resistor too...</p><p>Capacitor - Pretty large value</p><p>The sparks don't seems to be increasing. What could be the possible reason and how can it be increased. Please help!!</p>
<p>I used a 1K metal film 1/2W resistor with the TIP3055 and thats when the the arcs started working well for me, also ran three TIP3055's in parallel at around 25v worked pretty well, i found 3 turns on the primary was the sweet spot, though i still want to play with diameter of the primary. was pulling 1.6A so not too bad on the current draw. just blew up my new home brew power supply (again, patience wearing thin with that! especially when is my own stupid fault) so back to the old 25v for me for now. my cap is electrolytic 10000uF too but only 40V. also found more aggressive sparks with a thin circle disc of aluminium (1.4mm thick i think) as the capacitive load with a small brass ball or just a bolt popping up thru the centre (don't leave any metal hanging into the hollow of the coil, it will arc thru whatever you put there). I got the first circuit running well with the TIP3055 initially with just one and it got pretty hot quickly, but found it handled it better with three (lower heat, bigger arc) but the big &quot;aha&quot; moment was the resistor - give a 1k metal film resistor a try mate that nailed it for me, interestingly the carbon one of the same value performed quite poorly, but i couldn't tell you why that is. Now i just gotta build a psu for these things that doesn't produce more smoke than power.... ;) didn't know that about black PVC, that's interesting. mines all formed around white PVC including L1, just a bit bigger diameter, just meant it didn't move around on me with some blutack under the L1 PVC </p>
Umm, I don't know. It seems incredibly similar to my design. What did you wind the L2 coil around? Black PVC and wood are no good I hope you did not use that. Acrylic is best, standard white PVC is ok too.
<p>Initially i wound it around a White PVC. I didnt get large arc. So i thought winding it around a cardboard like how you have shown in the video will suffice. but still no improvement. So please help!</p>
<p>1st rule of debugging electronics! Thou shalt test voltages! Sure, your power supply might be 12V open circuit, but what voltage is it outputing when loaded? (when connected to this circuit?) Note, a digital multimeter may act crazy near the exciter, so connect the probes across the power supply directly across where it connects to the circuit, and keep the meter as far away as possible from the coil.</p>
Hey max....i have build the same following the steps u gave here but problem causing with me is the radiation....so can u plz tell me how can i overcome with it
??? I don't know what you are asking. Follow the troubleshooting steps at the end of the instructable for the version that you made.
How many turns should be there in the main coil?
<p>more = better, about 800 or so.</p>
What value of capacitor should be used in order to get better performance?
<p>Which capacitor? The decoupling capacitor, or the resonant capacitor in parallel with L1?</p><p>Decoupling capacitors do not need to be a specific value. Just low ESR and large enough capacitance to deliver the power quickly when it is needed.To learn more, read this article. <a href="https://learn.sparkfun.com/tutorials/capacitors/application-examples" rel="nofollow">https://learn.sparkfun.com/tutorials/capacitors/ap...</a></p><p>Resonant capacitors are used to increase oscillation at a particular frequency. Choosing the right one is a bit more tricky. You should know the resonant frequency for L2 is before hand. That requires you to know the parasitic capacitance between the coil and ground, as well as the inductance of the L2 coil. Then the formula f = 1/(2*pi*sqrt(L*C)) is applied. The only effective way to do it is experimentally. Try all sorts of values in the pF range.</p>
So basically i built a slayer exciter and worked fine. <br>My goal is to increase the arc.<br>I have used TIP31c and TIP3055 and both produced very small arcs. Im using a 47k resistor and two UF4007 diodes. The circuit is powered up by two 9V batteries given in series.<br>The primary coil is 16 gauge thick and 15 turns in total. The secondary coil is 26 gauge and around 200-300 turns have been wound around a pvc pipe and is connected to a metallic load on top.<br><br>To increase the arc, i wound three layers of secondary coil to increase the flux. Care was taken to see to it that there was continuity and was wound in the correct direction of current. Between each layer a piece of paper is kept to prevent from shorting. Theoretically if the no of turns in the secondary is increased further then automatically the output voltage should increase. But unfortunately, the whole model stopped working once i increased the turns. So please help me figure out a way to increase the electric field arc produced!
<strong>Honestly I think you basically did everything wrong lol! I am amazed it worked at all!!! Well anyways here is my advice:<br> <br> 1)</strong> A 47Kohm resistor is probably too high a value. Try 10K---1K.<br> <br> <strong>2) </strong>UF4007 are not diodes, they are rectifiers. And they are slow!!! Try using 1N4148 or 1N914, or a schottky diode. In fact, they are not really even required!!! The MJE3055 should be easily able to handle some zener diode breakdown on the base.<br> <br> <strong>3) </strong>200-300 turns is probably not enough. I used much thinner 30AWG wire with about 700-1000 turns.<br> <br> <strong>4) </strong>Why 15 turns? I only used 5. Look up the transformer turns ratio on google. It shows that the output voltage of a transformer is proportional to ratio of primary to secondary turns. More secondary turns and less primary turns both = more output voltage = larger sparks.<br> <br> <strong>5) </strong>&nbsp;Because we are working with a circuit that operates in the MHz range, winding multiple layers for the secondary is BAD. &nbsp;The overlapping wires have parasitic capacitance between them that looks almost like a short circuit. Also the dielectric breakdown of the insulation on the wire is not very strong. The voltages the output coil generates will easily destroy that insulation and actually short the whole coil.&nbsp;<br> <br> <strong>6)</strong>&nbsp;Paper does nothing to insulate. Its dielectric properties are crap. &nbsp;But this point is moot because of #5<br> <br> <strong>7)</strong> Winding more turns does not increase the flux, you can only increase the flux received by the secondary by increasing the cross sectional area of the coil or&nbsp;you can increase the alternating magnetic feild generated by the primary coil with greater dV/dT.<br> <br> <br> =======================================================<br> <br> So I recommend rewinding the secondary. If you didn't already destroyed the enamel on the secondary coil, you might be able to reuse that wire, but make only 1 layer, and wind neatly. Then reduce the primary number of turns. Refer to my troubleshooting guide for more advice on how to get it optimized.
Thanks a lot!
<p>Here is a good video describing what schottky diodes are/do. They are a bit more leaky (let current flow when reverse biased) but they are really fast to start conducting when forward biased and have very small junction capacitance.</p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/bXEyCf1P0UU" width="500"></iframe></p>
<p>hi i made the slayer exciter and it was super easy i used C5027S transistor and it poped a little but still working like magic :) and 47k ohm resistor and the secondery i don't know how much turns :3 with the topload and 6 turns on the primary and i used a green led !the circuit was powerd by 12v 2amps power supply.there was a little spark on the topload but it was so tiny how can i increase it?!</p>
If the transistor popped then it might have been damaged. Maybe it still works somewhat but lost some gain and cannot fully saturate, who knows. That's a pretty high voltage transistor, but it cannot handle much current. It's unlikely to fry it with any voltage transients from the primary, but current spikes might be enough to kill it because it does not have a high current rating.<br><br>Have you referred to my troubleshooting page to see how to get it working better. If you have exhausted all the options on that page then you may just need a different transistor or remake the primary.
<p>hey i tried with pnp A1129 transistor and it works okey only i remove led and flip the connection the the power supply when i use 24v the heatsink get's only warm and still getting small sparks and on the primary i used 3-5 turns ,nothing is changed only transistor and number of turns on the primary </p>
<p>Sounds like you are not biasing the transistor enough. Try smaller value resistor between base and ground. Either that or your power supply is not powerful enough. Make sure it is capable of at least a few amps. Power the circuit and test the voltage while the circuit is running. That is the only way to see if it is doing the job.</p><p>Also, if you are using long thin wires to carry the power from a power supply brick, you should add a capacitor directly across the power in on the slayer exciter. (a 470uF electrolytic capacitor + a large MKP or film or ceramic capacitor of a few uF should do the job.)</p><p>I do not have that transistor so I cannot help you too much more than that. You will just need to experiment with the number of turns, the polarity of the coil, and everything else listed in the troubleshooting page. It took me months of experamentation to get something that works for me.</p>
<p>hello sir i'm starting to wind the new secondery the old one was little about the transistor can i use 13003 mounted on heat sink ?</p>
IDK if that transistor will work or not, I do not have one. On the datasheet it looks pretty decent and specialized for high voltage switching applications. (Maximum 400 Vce) Just be mindful of the current. It is only rated for 1.5A, which is barely than a normal 2N2222.
<p>Hey -max- cool video mate (sound wasn't that bad, stop complaining you lot). Nice simple little circuit too, but your demonstrations were good, saved me a lot of messing around so thanks for sharing! </p><p>I initially ran a single TIP3055 and it got pretty hot with the eventual 24volts (only drawing 1.6A at this stage) and was running any ceramic caps i could find from old PSUs (had 3 in parallel, no idea what specs but they worked) i tried running two TIP3055's in parallel and it definitely made it run better - a more sustained and longer arc (and cooler). 1k metalfilm bias resistor and 63V 10000uF electrolytic capacitor to replace the ceramics - this also seemed to increase arc length and intensity. Old Pentium heatsinks for cooling transistors.</p><p>Primary coil is 3T of mains earth wire.</p><p>Secondary coil is 932T exactly (not that it matters but i had a counter laying around that i ran off the side of cordless drill on a roller microswitch and a &quot;cam&quot; to click it over, or piece of wire taped to chuck to be more accurate) so it was easy to keep track. 48mm pvc pipe for former. It measures 7.0uH on the dot (was a fluke as i didn't make any calculations until afterwards out of curiosity) and 50ohms resistance (again, a fluke lol). my only design consideration making L2 was make it as big as i can for about 20 bucks in wire. The wire is 0.25mm enamelwire with about four joins in it which are insulated with kapton (polyimide) tape then wrapped in kapton. Next step is to put circuit on a pcb and tidy things up a bit, all the wood was just scraps from the shed.</p><p>I learnt the hard way, remove all jewelry (<strong>especially gold wedding rings!!</strong>) before powering up your circuit - it won't electrocute you but it will definitely give you a nasty burn!</p><p>I'm pleased with it, works better than expected, sustainable arc approx. 3-4cm and starts reaching out to conductor at about 10cm (depending on top load). does all the light bulb tricks, and my favourite - the ion motor. I think i'll build the bigger one next with the 555 timer and inverted buffer driver circuit, that looks awesome. </p><p>Only thing i cant do is get a decent picture of it running, you did very well to get the pictures and video of the quality that you did max, i suspect any complaints came from ppl who haven't actually built one and tried to take a picture or video of it running themselves because it freaks my camera out something crazy so here are some pics of it set up but not powered and one of it powered with a single TIP3055 and a light globe sitting in a short piece of pipe to make it stand up, in real life it's purple/pink plasma, but on the camera it looks like this?! (very poor shot) and the latest build, and my burn (lol) and my &quot;coil winding jig&quot; (with my first coil, didn't use this coil, spooled the wire onto the new coil, but i didn't get pics winding the new one), i'm still working on getting some action pics and ill post them when i finally get the hang of taking pics of it running :)</p>
<p>Quick correction, the big electrolytic cap I'm using now isn't a 63v as i mistakenly stated, it's a 40v (it is 10000uF though, I got that bit right)</p>
<p>Nice build! Glad you got it working even better than I did! I have like 10 2N3055's I might give this older circuit another try, maybe with additional circuitry to increase positive feedback.</p><p>Taking good pictures is never easy, and I certainly didn't take the best pictures for this build! I just used my old GS3 phone and an entry level amature camcorder for photos and video. The result is blurry, grainy, and colorless photos. In fact, my phone's capacitive touchscreen and capacitive touch buttons would saturate from the strong EMI and the phone would do random things and become completely unresponsive if I got too close to take pics!!! I even killed an $80 mobius camera in a similar way! (thankfully the camera was pretty new and I got a DOA exchange! Upon inspection of that camera, there was absolutely no electrical shielding inside the camera, and an electrically floating heatsink, so I guess high voltage was induced into the metal heatsink and sparked to the microprocessor inside and killed it. Getting the new one, I fixed that issue and keep it away from the fun HV toys.)</p><p> Ideally, one would use a camera that has excellent low light performance. Low light performance will depend on the image sensor, its physical size, megapixel count (in this case, less is more. You want a LOW pixel density), as well as the lens and aperture size,(determines how much light does it let in.) The bad coloration of the spark may be due to a lack of IR or UV filters type of image sensor used. Image sensors tend to be good or even better at picking up UV and IR then visible light! You can tell if there is a IR filter on the camera by taking a picture of hot cherry red coals. If they look purple instead of red, then it's likely that there is no IR filter. That is good for making IR night vision, but bad for accurate colors.</p><p>And yeah, when you are near the circuit in operation, you are capacitively coupled to the high voltage, so even if you are not touching anything, there can be several thousand volts of AC on you, and if you go to touch any grounded object, that potential difference can give you a nasty zap and smelly burn! </p>
<p>Thanks mate, yeah my &quot;camera&quot; is a samsung g5 phn so i'm not sure what the low light capabilities are, takes pretty good photos of everything else but goes loopy when it's near this circuit, you're not wrong about the touch screen going nuts lol. might have to borrow a real camera and stick it on a tripod or something far enough away from it. I don't know if i'd say i got it running better than you did though (your video's the benchmark), but thanks to you're video i was able to skip a lot of headaches and see how things should work so thanks for posting it mate. It's pretty close to the results in your video so i'm pretty happy with it. It's amazing how you can be coupled to it at such distance, and this is a mini Tesla coil, the big ones must be pretty scary! I'd still love to see one in real life though :)</p><p>I'm pretty keen to build your SSTC, that looks very cool, just having trouble finding parts locally for it, i may have to order them (Jameco looks like the go) but i'll happily play with this in the meantime, the light globe on top with plasma in it looks like it's going to melt the glass, so cool!! The kids love watching it too (no touching obviously) and my wife is afraid of it (hehe perfect!). As soon as i figure out a camera and get some proper pics i'll post them (Gotta get some pics, or vids for that matter!). Thanks again for posting your videos, i've always dreamed of building a tesla coil but the full size ones are just a little bit scary to start out on so this is great! can learn the science and get familiar with it's behaviour at a scale that's manageable without killing myself, and work my way up to the big ones, next build - the SSTC, that looks like a fun circuit to build, i may need a bigger power supply though! I've just upgraded some parts on the one i've got and squeezed another 1.7v or so out of it, but it's still working pretty hard to drive this circuit lol :)</p>
<p>For the MOSFET version, you don't need to get that DS0026 chip, any MOSFET buffer driver chip should work, at least with some fiddling around. I just happened to have like 30 DS0026 chips in a electronics drawer, and they worked really well. However because they are obsolete parts, don't spend too much for that specific part number. In fact, I think it might be possible to just use a NPN / PNP emitter follower totem pole configuration.</p><p>I mainly used a Sony CX220 to record the video for the bigger one, I think I used the same camera for this older circuit. I got that camera because it was the only affordable camera that advertised a backlit CMOS image sensor, recorded 1080p 60FPS, and had optical image stabilization. However I was not too impressed with low light performance. Very grainy, but I guess for less than $200, it's acceptable. I experimented with video enhancements like a unsharp mask in post production, and it seems like sharpness and graininess are tradeoffs. (a clean but soft image, or a sharp but noisy image. Pick your poison. I picked the latter.)</p><p>I think someone in the comments has built the MOSFET version of this circuit with 170Vdc directly from the walls!!! I would like to get this circuit to work that well, although I would like to test at half that voltage first. Doing that, the circuit would need some modifications particularly in the method used to create a low voltage 12V for the 555 section.</p>
<p>Hey Max, sorry took so long to post back, here's some pics of the coil finally (i think the trick for me was getting someone else to take them haha). also included a pic of the circuit (2 transistors) and the transformers i scored from a big UPS (working, but in the bin lol).haven't had a chance to test them yet but hopefully tonight when kids are in bed. Right after the pics were taken of the coil, one transistor let the smoke out and the other blew the front of it out (pretty loud, i was more impressed than concerned). Rebuilding now with 3 transistors then gonna move on to the SSTC, thanks for the info about the inverted buffer driver, i'll start getting the parts together. I'll post what the outputs are from those transformers too once i get a chance to test them (was 240VAC 15A input so i reckon they might be too big perhaps?)</p>
<p>ooh that soldering is definitely not my best work, i was using a gas iron for that cos i couldn't get my good electric one out at the time so it works, but it looks horrible, i'll print a pcb outlay at some point and post the jpeg if it turns out well enough, i kinda rushed assembling this circuit cos i wanted to see it working again lol.</p><p>The output from those transformers were wired in series too so should be interesting anyway, think i know where some smaller ones are in some other smaller scavenged UPSs i have floating around, gonna take a couple apart tomorrow and see if they're any good cos to be honest, those big ones just look too scary haha, but i will test them they may be just right despite their imposing size (and weight!!) just take all the precautions first. too tired now to play with that, bed time... ill do some more in the morning when im feeling sharper lol</p>
<p>If the coil breaks while winding, can I solder it back together and continue..mine broke and I did this..but dont know if it suffers strength....or output...this was the first one I made.</p>
<p>First one I did, I had a few breaks in the wire. Try to use something 30AWG or thicker (like 26AWG). Breaks are not good, they make it look sloppy and act as points of leakage for charge.</p>
<p>which uses capacitors you in video???</p>
???
<p>Can I please have a full list of materials (<strong>well the list of the ones that worked</strong>)</p><p>for my science fair in I think 3 months. Thanks!</p>
<p>Everything is on step 3! http://www.instructables.com/id/building-the-poor-mans-mini-tesla-coil-slayer-exc/step3/Things-you-will-need/</p>
<p>sorry did not see that...</p>
<p>Hello, I am trying to understand the calculation behind the circuit, are the primary and secondary work like a transformer or better like Ruhmkorff induction coil ? Can i so apply the following equations... (N1/V1=N2/V2) and (V1*I1=V2*I2) ?</p><p>Also how can I calculate the frequency? Thanks for your time.</p>

About This Instructable