HOW TO BUILD A TESLA COIL

HOW TO BUILD A TESLA COIL

by Steve Gantt

(713) 684-6269 (VOICE)

(713 688-2058 (FAX)

I like alot of other folks seem to be driven to explore the

uses of high voltage devices. I do not know why exactly. Hey,

maybe I was abducted by aliens, and realize that by the

understanding of how high voltage and frequency react on

matter we might be able to beat the impending alien

invasion... Or, then again I might just find this fascinating

.  At any rate, I thought that I might share my experience in

building a tesla coil, and give you some pointers.

Question :

Building your own tesla coil is about as difficult;

A. as baking your first cake

B. rebuilding your first automobile engine

C. A final exam on "Nuclear Fusion as it relates to Electro-

   dynamic Variations in Adjacent Ferrous Materials as

   Opposed to Standard Electromagnetic Pulses"

( The answer is A )

You should be able to complete this project in your spare

time in about a week. Five days you will be required to watch

the DISCOVERY Channel or any other channel that will help you

through the boredom of winding the tesla coil (often called

the secondary).

First you will need about $ 70 to get all the materials (see

the attached parts list). After you have purchased everything

you need to build the coil, start on that first.

The Tesla coil itself is constructed from a 3 foot piece of

4" PVC pipe (if you go the hardware store & want to impress

them, tell them you need 3 feet of 4 inch Schedule 40).

Next you will need about 1 & 1/3 pounds of # 26 AWG magnet

wire. By wire by the pound ? Yes ! that is how this wire is

usually sold. Get two pounds it's not that expensive, and

besides you might want to experiment with it later. Now CAN

use #30 AWG or # 28 AWG or # 24 AWG but if you use other wire

the coil won't work as well ( the coils is based on some

complicated algebraic formulas, and is dependant on # of

turns, length of wire, etc.).

Now drill a small hole each end of the PVC about 1/2 inch

from the top and bottom. Shove one end of the wire thru one

of the holes and leave about a foot of wire on the inside.

Take some tape and put it over the wire so you don't pull it

out like some dummy I know did (me). Now comes the winding...

Place the PVC on the floor in front of the TV, turn the

channel to some movie, the Discovery Channel or something

else, get you something to drink, and have a roll of tape a

pencil and paper within reach. Now start turning the pcv

allowing the wire to wind around it. Count ten full turns.

Move all the wire down so that it looks real pretty and that

no wire has jumped on top of another. Kinda pull it tight,

place some tape over it, and mark down ten on your piece of

paper. You are now 1/160 th's the way there. You will need a

total of 1600 turn on this PVC. Make sure that no wire is on

top of another, be sure to pull it tight ( but DON'T BREAK

THE WIRE !). If you DO break the wire or you run out in the

middle of the 1600 turns then...

Use some sandpaper to get the enamel off the end of the wire

and solder the two loose ends together. Make it a real pretty

solder job, no sharp edges, no blobs of solder, etc. then

coat the solder joint with your favorite high voltage dope,

or non-metallic fingernail polish, whichever you have

handiest. Keep winding, keep counting. Keep putting that tape

on so it doesn't unravel on you. When you finish counting to

1600 then ...

Cut the wire so that you have about 24 inches of wire left,

place it through the other hole in the pvc. DON'T take the

tape off yet. Secure the wire on the inside with another

piece of tape. Now take your almost finished tesla coil

outside and start spaying it with "Non-conductive Fast-Drying

Clear-plastic acrylic paint" ( Go down to the hardware store

& get a couple of cans of clear acrylic spay paint). and put

about three coats of paint on the coil. Now take the tape

off, check for loose wire and wire that has gotten on top of

other wire (Take time to do this right. It's not difficult,

just time consuming). Now spay about another 6 coats on. If

you have finished with the six coats, just use up the rest of

the paint with extra coats.  Be sure to let this stuff dry

well between coats.

Okay now we can start on the Driver...

If you can solder & read schematics then go to it & skip

ahead to the OPERATION Section...

If you have never soldered before, or have never built any

circuits before, then I suggest you practice first.

Take the perfboard and place the LM567 in the top third of

the board about four rows from the top. The LM567 will have

either a notch in the top or a dot over pin 1. Now bend over

pin # 8 ( it is not used and will help hold it in place for

you. Next take your .1 MFD caps and put then in place one

hole over  next to pins 1,2 & 4.

Solder one leg to  those pins.  Now hook up everything else

as shown in the schematic.

To make T1 you will need to take the AMIDON ferrite core.

Remove the bobbin and wrap 15 turns of the # 26 AWG , spaced

evenly, leaving about a foot of wire at both ends. Then wrap

it with tape. Now mark the ends of the wire so that you know

what they are.  Now take the other piece of the ferrite coil

and wrap about 120-150 turns on it leaving about a foot of

wire on each end ( yes, use the same #26 AWG wire). Cover

that with tape. Now put the bobbin back in.  Now wrap the

entire thing with a few layers of tape, making sure you know

which wires cane off of the bobbin (primary 15 turns) and the

other (secondary 120-150 turns).

After you have completed everything, co back and check all of

your connections. Check them again. Then get a friend to

check them.

If you don't have a 18-24 vdc power source you will have to

build one. Use the package called 24VPOWER. This file is with

this package.

OPERATION SECTION

Set up the TESLA coil so that it stands vertically on a

table. Remove everything from around it, especially

diskettes, VCR tapes, credit cards, etc. hook the bottom wire

from the coil to the tesla coil driver. The upper wire should

remain inside the PVC, taped to the side. Put the switch on

TUNE (if you don't do this you will blow the LM567) and apply

power ( turn it on ).  Adjust the trimpot so that both LED's

are about the same brightness.  Now you can switch off the

tune switch.

You should be operating now. Hold a florescent tube up to the

top portion of the coil and it will glow. You will see some

little sparks if you touch the coil on the top portion. You

now have an operating Tesla coil.

What to do if you run into trouble.

1. Check all your connections

2. Have a friend check all the connections.

3. Call you mother and have her check all the connections.

4. Use a multimeter & check the voltage between ground & pin

   # 4 of the LM567. It should read about 8 VDC. If not  and

   step 5 checks okay then replace the 7808

5. Check the voltage between ground and the input of the

   7808. It should be between 18-24 VDC. if there is no

   voltage then you have a bad power source.

6. Check voltage ( frequency if you have it) on pin #5 of

   LM567. If there is any voltage or frequency, then the

   IRF511 is bad, replace it.

7. Other things to check after the above.

     a. Make sure the primary and secondary of T1 are not

        reversed.

     b. If the LED's glow, then everything is operating ok up

        to that point. Use a multimeter & check OHMS between

        the upper and lower wires of the tesla coil. It

        should read about 0 ohms.

     c. Pray

     d. Spit on it

     e. Use abusive language

     f. call me

             Tesla Coil Parts List

                                                              APPROX

STUFF TO GET AT THE ELECTRONICS STORE (or Order)               COST

LM567 Tone Decoder                                             3.25

7808 Voltage Regulator                                         4.25

1 1/3 pounds of #26 magnet wire                               15.00

AMIDON EA-77-250 ferrite core and bobbin                       5.75

STUFF TO GET AT RADIO SHACK

IRF511 hexFET                                                  3.75

LED (2 each)                                                   1.99

1000-ohm 5% resistor 1/4 watt                                  1.99

100 ohm 1 watt 10% resistor                                    1.99

25 K ohm trimpot ( 10 turn is best ) used to adjust frequency  2.25

0.1 MDF @ 100 WVDC ceramic disc capacitors ( 4 each )          1.99

680 PF  @ 100 WVDC ceramic disc capacitor                      1.99

470 MDF @ 50 WVDC  electrolytic capacitor                      1.99

2" X 3" perfboard                                              1.99

1 SPST toggle switch                                           1.99

STUFF TO GET AR THE HARDWARE STORE

3' X 4" PVC or Plastic Sewer Pipe                             7.50

2 cans of clear-acylic spay paint                             7.00

          24 volt Power Source

Parts List

You can get all the following stuff at Radio Shack

for about $ 25

24 volt Transformer                     5.95

Rectifier Bridge Assembly               2.99

10 MDF @ 50 WVDC                        1.99

.1 MFD @ 50 WVDC                        1.99

1 DPST SWITCH                           1.99

1 fuse holder                            .99

1 1/2 AMP 250 V fuse                     .99

1 Box to mount all this stuff in        4.95

12 ' electrical ZIP wire (2 conductor)  1.25

1 Plug                                  1.99

See Schematic