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
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
------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
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.