Introduction: 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.
--------WARNING---------
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.
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
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.
------THEORY OF OPERATION------
- 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
------THE SECONDARY COIL------
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
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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375 Comments
Question 11 months ago
Hello if I use a tip 32c pnp transistor and a 16v 650miliamp alim what I do change in the circuit (the polarisation of course but what else) because I've do the mountage without diodes with multiple resistors (100k 50k 250k 500k) and the transistors do heat and die... (RIP my English) the question is : the diodes are indispensable? What is the sense of the diodes for my circuit. And what the value of resistor I do use for 16v?
3 years ago
Hello there. Hope you're well.
Thank you for your project.
I have a practical question:
If I use it to wirelessly power a lamp, how long a brand new 9V alkaline battery would last?
Any real-life experience?
Question 3 years ago
I'm building one right now and I've gotten the reverse biased led on the feedback to light but nothing. Still tweaking but wondering what your thoughts are to build circuit in question using a vacuum tube ( assuming I can provide filament and plate voltages etc)
4 years ago on Step 2
This is the best explanation I have ever seen! Thank you!
7 years ago
Hi Sir,I had build a Tesla coil using a circuit as the image show but when connected the 9v battery the transistor become very hot and is not working. The picture I took it without the battery.Please help, I need to fix the by thursday. Thanks
Reply 7 years ago
Um.. hi so, I am not in a place to say anything as I haven't made it myself as of now but from what I can see, the your primary coil has around two coils try increasing those as this instructable also recommends at least eight coils for 18V of power supply so by doing the math the least no. of coils in yours (if the power supply really is only 9V) should be four. But you can try increasing (or decreasing )the no. of coils even further until it's working alright.
*Oh and yeah I kinda don't know why I wrote decreasing the no. of coils but you can try that too right :)
Reply 7 years ago
Thanks for your answer.
On the video from Youtube were I got this, they only say that 2 coils are necesary and a 9 vots battery (please see the attached pic). I will try with more today. Also the secondary coil have 140 turns.
Reply 4 years ago
A fast diode (ultra-fast recovery or Schottky) is required between the
transistor base and emitter to prevent reverse current flow to the
transistor base.
Reply 7 years ago
hi uh.. again i guess. I get your point but i still need to see the video to make sure that the instructions were correct or not. Well but anyways did you still try increasing the no. of coils in the primary coil (just to see what happens, you know :p)
Reply 7 years ago
This is the link for the video on Youtube were I got the instruction.
I made some changes in order to make it work but I couldn't. I change the PVC tube (larger one) in order to have more secondary turns (I reach 400) and I made a 8 turns primary but didn't work. I will try with more primary turns in order to see if it works. I appreciate your advice.
Reply 7 years ago
Try reversing the connections of the primary coil. Switch the top end of the primary to the connections where the bottom end of the coil on your circuit and do the same for the bottom.
4 years ago
Hello Chip.
I'm sorry that my comment was delayed. I took a lot of time to find this page.
Apparently many people are confused by mistaken UF4007 and 1N4007. We have to tell them clearly that the numbers are similar but the characteristics are quite different in UF and 1N. I think that detailed explanation about this diode is necessary. And I noticed that I think it is better to put a 22uF bypass capacitor on the power supply just in case.
9 years ago on Introduction
PLEASSSSSE HELLLP......I did everything correctly. According to the circuit diagram.......but my model is still not working......I'm using a tip31c transistor.....47k resistor...and 2 pieces of 1N4007 diodes and I also soldered everything in correctly...but it's still not working.....I'm attempting to light a CFL 5 watt lamp(230 v cuz I'm in India) and also a small bulb....but it's still not lighting up.......the transistor's base collector and emittor are diff from the diagram where the base is not in the middle... But I connected everything accordingly ......pls HELLP.....by this Wednesday ........
Reply 4 years ago
1N4007 is a power supply rectification diode. It is a very slow diode so it does not work at this frequency.
This requires ultra-fast diodes such as BAT46 and UF4007.
Reply 9 years ago on Introduction
The pins should not be different... Try flipping the primary leads. Also, one 9 volt battery may be too little power for such a large coil, try putting two 9v batteries in series. Nice job on winding the coil by the way!
Reply 9 years ago on Introduction
one thing i can tell you which chip fix have suggested me earlier that make the distance between the top load and the end of the secondary coil short, not more than one inch.
10 years ago on Introduction
Very Very Very good Project. I m so happy . It works with 700 turns and 7 turns of Primary my 5 Watt CFL is glowing
Reply 4 years ago
It's great!
I wish I had invented this circuit 20 years ago. Application to this inverter is possible.
https://commons.wikimedia.org/wiki/File:Micro_Tesl...
Reply 10 years ago on Introduction
Glad to hear it!
9 years ago on Introduction
Chip, I'm from Philippines and I just want to ask if it is ok to use 1N4007 diode instead of UF4007 because it's not available here.