Picture of How to Build a Slayer Exciter

A Slayer Exciter is an air-cored transformer that steps up a very low DC voltage to a very high AC voltage. This creates an electromagnetic field around the coil that is capable of lighting up fluorescent and neon light bulbs. It is fairly similar to a Tesla Coil.

The Slayer Exciter was the brainstorm of Dr. Stiffler and GBluer a few years ago. It has since been modified and improved, resulting in a community of people whose hobby is to revise and improve them.

In this Instructable, I will show you how to build a small Slayer Exciter and will also give an explanation as to how it works.

There are several parts that make up a Slayer Exciter:
- The power source supplies the voltage and amperage.
- The driver circuit takes the electricity from the power source and prepares it for the transformer.
- The primary coil creates a magnetic field from the electricity.
- The secondary coil converts the magnetic field back into electricity and steps it up to a much higher voltage.
- Finally, the top load acts as a capacitor, greatly increasing the strength of the electromagnetic field.

The whole project only costs about $15 and can easily be completed in a weekend. It can be used as a centerpiece for the dinner table that will "wow" any family members or guests. It is also easily transportable which can make it a great conversation starter if you choose to bring it to school or work.

The Slayer exciter creates an electromagnetic field that may negatively affect electronic equipment in the immediate area; including pacemakers. Exercise caution and common sense when operating a Slayer Exciter.

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Step 1: Parts List

For this project you may need to do a little shopping. Luckily, everything can be found around the house or bought on Ebay. The total cost for the project can easily be kept under $20.

Items Needed:
-   At least a 6" long tube that's 1" in diameter, it must be hollow and non-conductive! I used a
     piece of PVC pipe. - ~$5
-   A platform to mount everything onto. I used the bottom of a CD case. - Free
-   Approximately 3' of 14 - 26 AWG wire. - ~$1
-   Approximately 100' of 30 AWG enamel wire. - ~$5
-   Some sort of round sphere to use as a top load. - ~$1
-   One 47,000 (47k) ohm resistor. - $1
-   Two UF4007 diodes. - $1
-   One TIP31C transistor. - $1
-   Screw terminals (Optional). - $1
-   Transistor heat sink (Recommended if exceeding 18 volts) - $3

Feel free to experiment with different transistors, most transistors should work as long as they are NPN type. However, if the transistor gets hot to the touch you may want to consider the TIP31C, the TIP31C should only get warm to the touch unless you exceed 18 volts. The resistor value can also be changed, it merely limits the current going into the transistor so a change of a few thousand ohms either way should not make much of a difference. If your transistor feels hot to the touch you may want to consider increasing the value of the resistor.

I would also recommend using a piece of pipe that's several inches longer than what is required, you can always cut down the pipe to the right size after wrapping the secondary coil.

Step 2: The Driver Circuit

Picture of The Driver Circuit
This design is very simple and only uses four components! It is also very versatile and the input voltage can be as low as 5 volts or higher than 18 volts if the transistor is attached to a heat sink.


-   5 to 18 volts is fed into the circuit, a resistor (R1) is placed before the Base pin of the transistor in order to limit the amount of current the pin receives. If too much current is allowed into the Base pin the transistor can produce excessive heat and fail.

-   One end of the secondary (L2) is connected to the Base pin of the transistor in order to feed it with oscillations. The two diodes (D1 and D2) prevent the oscillations from going directly to ground. (Learn more about oscillations and why they're important, below).
-   The transistor is made up of three pins: the Collector, the Emitter, and the Base. If you were to think of the transistor as a garden hose spigot (See picture 2), the Collector would be the reservoir of water. The Emitter would be the hose and the Base would be the valve that would allow water from the reservoir (Collector) to the hose (Emitter). The valve (Base) is in the closed position (no water flowing) until it is given a little nudge. When it receives a nudge, the valve opens and a lot of water is allowed to flow from the reservoir through the hose as long as the valve is still getting a nudge. However, as soon as the nudge goes away the valve will close, cutting off the water from the reservoir to the hose until the valve gets another nudge.

-   When the Base receives a little bit of current, it closes the circuit and electricity is allowed to flow through the primary coil (L1). However, electricity likes to take the path of least resistance so when the electricity is allowed to flow from the collector to the emitter (~0 ohm resistance) it will stop flowing to the base because there is 47,000 ohms of resistance there. When the electricity stops flowing to the base, the base will open up the circuit again until the resistor offers less resistance than the Collector-Emitter path. This cycle repeats itself many times a second.

-   The primary coil collapses when the electricity stops flowing through it, when this happens, the secondary coil picks up the magnetic field and converts it back into voltage which gets stepped up to around a thousand volts in the process. The top load acts as a capacitor and increases the output from the secondary causing electrons in the air to become excited.

-   Finally, the oscillations from the secondary coil are fed back into the transistor in order to 'tune' or achieve maximum output from the Slayer Exciter.

Step 3: Making the Coils and Top Load

Picture of Making the Coils and Top Load

In my opinion, designing and making the secondary coil is the process that takes the most time to complete. 

Step 1: Calculate the Specifications of the coil (1st picture).
While there are several ways to figure out how many turns to wind on your secondary, I just went with 400. To figure out how much wire I would need I found the circumference of the PVC pipe. The equation for this is Pi * D where Pi = 3.14 and D = the diameter of the PVC pipe which is 1". So I did 3.14 * 1 which equaled 3.14" So I would need 3.14 inches of wire to make one turn on the secondary. I knew I wanted 400 turns so I just multiplied 3.14" by 400 and came out with 1,296" of wire. I divided this number by 12 to get the length in feet and the answer came out to be 104.67 feet of wire. Since I'm not particular, I rounded it off to an even 100 and measured out the wire on my living room floor.

Step 2: Get the wire ready to wrap around the secondary ( 2nd picture).
After the wire was measured out, I wrapped it around a Tupperware container that was covered in double sided tape. This container prevented the wire from unraveling while I was wrapping it around the pipe.

Step 3: Wind the secondary (3rd picture).
This step takes a lot of time so make sure you are comfortable and have plenty of Painters Tape on hand in case you need to take a break. My secondary took about two hours to wind. You are going to want to start off by taping one end of the wire to the pipe, make sure you leave about a foot of extra wire so you can connect it to the driver circuit. Then you are just going to wind the wire around the tube being careful not to overlap the wire in any places. When finished winding, (again, leave a little extra wire to attach to the top load) tape down the end to the tube so it does not unravel. Now you have two options, you can either coat the whole tube in a general purpose epoxy so it will never unravel or you can just leave it. I ended up just tacking a couple spots of the coil with Gorilla Glue because I was out of epoxy. Although, I highly recommend coating your coil in epoxy! 

------THE TOP LOAD------

The top load does not need to be fancy, a metal ball would be ideal but pretty much anything round or toroidal shaped will work as long as it's coated in something metallic. I used a wooden knob I found at a parts store and wrapped a sheet of aluminum foil around it. You will need to attach one end of the secondary coil to the top load via screw or solder. Then just attach the top load to the secondary, I used hot glue to keep it in place.

------THE PRIMARY COIL------

This part is very easy, all you have to do is wrap a length of wire directly around the base of the secondary like I did in the last picture. I would shoot for somewhere between 5 and 15 turns, I found that 8 turns worked the best for me.

Step 4: Putting it all Together

Picture of Putting it all Together
Ta da! Just add your power source (I would try a 9v battery first) and you should be able to make the 4 watt light bulb light up when you bring it close to the top load. In the first picture I used a variable power supply set to 15v to make both a 13 watt and 4 watt light bulb light up wirelessly. The range of the Slayer Exciter is around 6 inches at 9 volts and 1 foot at 18 volts.
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I have followed the instructions as best as possible, but I am having a problem.

My voltage at the top of the secondary is the same as the input voltage. Any ideas?


aniansh1 month ago
Hello everyone, i want to make this as my science project. But i am confused. I can't seem to understand the need for two diodes in the circuit. What is the function of two diodes?
AdityaT32 months ago

***Please reply. This is an EMERGENCY***

Hello! I have been trying this circuit for a while now but I haven't succeeded in making it. I have used all the components you have mentioned and also tried replacing them with other equivalents but it just doesn't seem to work.

I get no voltage across the primary even when taking the input voltage up to 18 volts. And even when I do get a little voltage at times there seems to be no induction between the coils. I have used a 22 AWG coppoer wire for the primary (4-5 turns) and a 30 AWG wire for the secondary. The secondary is roughly 7-8 hundred turns (diameter of the secondary being roughly 1 inch and the length being roughly 7-8 inches).

I have been used a MJE3055T and also TIP41C transistors but didn't get any results.

I suspect there is a problem with the coils because it seems I have been doing everything correctly except for the coils.

Please help! I have to present this project on Sunday, Feb 1.

Thank you!

Chip Fixes (author)  AdityaT32 months ago
when you're running it at 12+ volts does the transistor heat up? Did you try flipping the leads on the primary coil? Did you try running it without a topload?

Thank you very much for the reply! I appreciate it a lot

Well, I have been using a heat sink with the transistor that could be why it doesnt really heat up. But the heat sink does get slightly hot after turning the circuit on for a while.

Yes, I have tried flipping the leads on the primary. I also tried the circuit without the topload.

The problem is that I dont get any voltage or oscillations across the primary.

But an LED lights up pretty nicely when it is connected in the place of the primary coil, i.e. to the positive rail and collector. So i assume that the transistor is working fine.

I also tried using a thicker wire for the primary but I still get no voltage across it.

I would really appreciate your help! Thank you!

Chip Fixes (author)  AdityaT32 months ago

The transistor heating up is a good sign and it sounds like the driver part is wired correctly (not necessarily working correctly though), especially with the LED test. Since you're using a slightly higher rated transistor, I would lower the value of the base resistor. Try 10k ohms, maybe 5k ohms (monitor the heating of the transistor when you do this). I'm thinking the transistor isn't being allowed to switch on/off.
Have you tried measuring the voltage from the top of the secondary coil?

Thank you so much, Chip!!!! The circuit is finally working!!! I got CFLs and Fluorescent tubes lighting up upto 3-4 inches away from the coils! It seems that once I replaced my old primary with a thicker one and the secondary with a nicely made non overlapping one, all I needed to do was check if the CFL was lighting up when brought near.. but I had failed so many times doing this that I just kept trying to measure the voltage and oscillations across the primary. Just as you said, I should have measured the voltage from the top of the secondary. Later when I was fiddling around with the circuit I found that there were sparks when any wire was brought to close to the secondary. As soon as I saw this I brought a CFL close enough to the secondary and VOILA!!! The lamp lit up! Thank you so much! Wouldn't have been possible without your help! The range has to be increased though.. you have any suggestions? Thank you! ^_^ :D

Chip Fixes (author)  AdityaT31 month ago

Oh good! Glad to hear it! Yeah the secondary coil is a critical part.

To increase the range, make a larger secondary coil with more turns and increase the input voltage.

ahmad.habib12 months ago

i can't find awg enameled wire in here(or maybe i haven't searched enough), but i find something that called as "insulator wire"(the wire used in insulator) and the diameter should be about 0.2 mm. Will it work if i used this cable instead of awg enameled wire ?

sorry, i mean inductor wire( the wire used in inductor)

What does a top load function as?

Chip Fixes (author)  thotthecreator3 months ago
It acts as a capacitor between ground and the top of the secondary.

Hello! I am a high school student and I am researching topics to do for my science project. Slayer Exciters (and tesla coils) intrigue me and I would like to know if you could explain how they work exactly before I consider it as a choice. You stated that: "A Slayer Exciter is an air-cored transformer that steps up a very low DC voltage to a very high AC voltage." Would you mind explaining what that means (like what is DC voltage and AC voltage)?

fmarquis made it!4 months ago

I had tried this circuit before without success, when I was just starting building stuff. Browsing the site in search of something evil to build, I came back to this old favorite of mine. After spending more time finding where my secondary was hiding than breadboarding the circuit, it worked perfectly well on the first attempt.

I don't know what went wrong the first time... One hypothesis is the ambient humidity... Here in Montreal, Canada, it is already below freezing and tonight, the air is quite dry. Or it could just be related to my improved capacity to read/build from schematics!

The second picture shows what happens when you check the transistor temperature with very cold (like "I'm working in my shed by minus 5 Celsius") fingers. For a moment, I was happy that my transistor was holding the current quite well.

Actually, it was not. And this time, the smoke was not coming from a dead transistor, but from my finger. You can clearly see the silhouette of the TIP31C...

I learned many things tonight, the first one being : "Nothing looks like a cold transistor more than a burning hot one, especially to cold fingers.".

Lesson learned the hard way.

Thanks for the Instructable. I will try to make a more permanent one now that I know it's working!

2014-11-15 20.04.58.jpg2014-11-15 20.13.33.jpg

hey there thanks for the instructable. just want to know that how much the transistor can take without a heat sink. mine is a TIP31C CC039 m using a 50 k resistor

Chip Fixes (author)  thedevilhunternero4 months ago
I wouldn't go above 12 volts, but you can feel it with your fingers to see if it gets hot or not.

we use the tip41a transistor,a 100 nanofarads ceramic capacitor,10
kilo ohms resistor using a step down transformer of 220 to 12 volts, the
result is the aluminum foil as a top load will going to melt and the
transistor is over heating quickly. we connect the secondary coil to the
base parallel to the 10kilo ohms,then the the two 100 micro farads
parallel connect to the emitter and the ground.

can you add photo of driver circuit in detail pls and can we add capacitor

Roosafeedk6 months ago

I made it, but it does not have enough range. It can hardly light an LED that too when it is in contact with the topload. How to increase the output?

I am using 2 9V batteris, IN4007 diode, 1M resistor, and TIP31C

L1 has 6 turns and L2 around 800

Hello ;) I tried this circuit with tip29c and now with 2n3055 as well,
but none is working.For the 2n3055 I'm using the 47k resistor you
recommended and 12V, but nothing happens.Could you help me please?


heyy i tried to make it but cannot find TIP31C transister but i got a tip41c transister. will it.

and the second question is do you send me some material which have detailed explaination of its working of all component i am little bit confuse on its circuit.

question is that the led has two terminal +ve and -ve. so in air, how can he
get the both terminal current that is phase and neutral.

ferdinand00229 months ago

can i use a 26 awg wire as secondary and a 18 awg wire as primary???

what is to be the output voltage for wireless transmission??

please suggest a method o contact you other than instructables...

Chip Fixes (author)  ferdinand00228 months ago

26 awg is a little thick but you could try it and see, you might just need a larger input voltage. 18 awg for the primary is just fine. The voltage output can be calculated by the formula:
Vp/Vs = Np/Ns
Where Vp = voltage of the primary, Vs = voltage of the secondary (what you're trying to find), Np is the number of turns on the primary, and Ns is the number of turns of the secondary.

You can rearrange the equation to: Vs = Vp/(Np/Ns) to solve for the secondary voltage output.

irfanhabib188 months ago

i tried to make it but at first the transistor was becoming very hot.. then i changed the poles or ends of the primary coil but it still did not work...... i supplied a 6v - 2 amp dc supply . the secondary coil was more than 1200 turns and primary was 8 turns... i used 1N4007 diode instead of the UF 4007 diode but all the other things are same... i tried to glow a 5watt - 220 volt cfl lamp ... please help me out

Chip Fixes (author)  irfanhabib188 months ago

You're going to need more than 6 volts to power a light bulb, try 12 or 18 volts.

AnubhabC made it!8 months ago

Hey Chip Fixes,

I have used 2 nine volt batteries. 1 LED(in place of diodes). about 1200 turns in L2 and 15 turns in primary coil(lower turns doesn't work properly). I am not sure of the value of the resistor i am using and no capacitor But the results are not satisfactory!

It is too weak as you can see in the images! What can i do? Whats your suggestions?? There is a detailed description here:

Chip Fixes (author)  AnubhabC8 months ago

You can try a few different things, reduce the amount of primary windings (I would go somewhere between 4 and 8), increase the input voltage, reduce the value of the resistor.

kshakkor8 months ago

hey uh chip Fixes,

i got transistor off TIP 35,tip 132,tip 135,tip 122,tip 122.will those work amigo.

Chip Fixes (author)  kshakkor8 months ago

TIP35 will work, you will probably need to add a heatsink of some sort though.

ferdinand00229 months ago

hi, Chip Fixes,

i cant get my slayer exciter to work.i did the same as you winding looks perfect.when i bring any bulbs near it,it wont light up.The current is flowing through the circuit.

Once the bulb had lighted,but was very faint. but then it wasn't lighting at all.It did not work.the components are working fine(tested using multimeter).

I think primary coil is the problem.I dont know how to adjust it...Please help...??

mine also has a heat sink and am using 18v.

Chip Fixes (author)  ferdinand00229 months ago

Try reversing the leads of the primary coil, you can also try using less turns on the primary. If that does not help, the transistor may be the problem.

Thanks sir, but i am getting reading in my multimeter. The current isn't ionising the air and the CFL is not lighting.once after experimenting a lot, i got an led of about 3v to light faintly.i tried decreasing the no:of it is about 3-4 turns.with 18v.i am doing this for my school project.
i thought it was the problem of the top load as i used a torroid shape in the place of a sphere shape, and i changed to sphere. Any solution??
Doctor90250 9 months ago

okay I have to add this. I did something totally cool with mine. first I got 1/4 cup of salt, opened a yellow highlighter and rubbed salt all over the ink cartridge until it was all yellow. once it was completely dry I put it into a small metal cup and placed in on the topload. I turned off the lights, turned on a black light and powered it up. the result was a spectacular fluorescent yellow fountain about 3 feet high!!!!
I wasn't able to get a good photo but I can post this without one, so I'm using the original one of my exciter.

Chip Fixes (author)  Doctor90250 9 months ago

Oh that's really cool! Could you get a video? I've seen salt added to high voltage outputs but never anything like that.

Hi chip,
Once I build the new one I will certainly try to get it on video.
Another way of doing it is with a van de graff style electrostatic generator, or anything that has a fairly decent ion wind.
Doctor90250 9 months ago

I built this using a TIP 122 transistor, and rather than winding my own secondary coil, I used a TV flyback transformer.
I wound about 8-10 turns of enamelled wire around the ferrite core. forgetting how much current my 12v regulated power supply put out, I tried powering it with that. let's just say that that transistor was not too happy about, and exploded with a violent BANG!
Now that I've recovered from the heart attack, it's back to the old drawing board. this time I'll use a wee bit less amperage, lol.
I did, however, on the first run, use a 9v 700 mA transformer just long enough to hear that wonderful high pitched hiss that flybacks are known for, before soldering it all together and returning my wife's DVD player to her. Suffice it to say, it works great! thank you for an awesome 'ible.
(in the 2nd pic you can see the hole in the transistor. I added that one for the chuckle factor, lol).

Chip Fixes (author)  Doctor90250 9 months ago

Thanks for sharing and that is an impressive failure hahaha. I think the reverse EMF from the flyback may have been the primary cause of the transistor exploding. If you were to add a safety diode between e and c of the transistor, it may last longer.

deba1681 year ago
sorry..the message was not complete. can i make a plasma globe by placing a incandescent light bulb instead of top load..
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