RE: Hello world!

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Winchester, David by way of Terry Fritz <twftesla-at-qwest-dot-net>" <David.Winchester-at-compaq-dot-com>

Thanks for the copious input!  You pretty much confirmed the direction I was
going in with NST, MMC caps, multi-gap spark gap, etc.  I'll let yuou know
how I do.  I amgoing to start looking for NSTs today.

Thanks again!

Big D

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Wednesday, June 13, 2001 8:30 AM
To: tesla-at-pupman-dot-com
Subject: Re: Hello world!


Original poster: "Jason Petrou by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<jasonp-at-btinternet-dot-com>

Dave - Comments below

<snip>
> For my first project, I plan to build something simple from readily
> available parts.  If you have a good first project candidate, please let
me
> know.
</snip>

Righttt.... where do I start?

Firstly you need to buy a transformer. This will determine the other
variables that you can use for your coil. Many first coils are based on the
NST or Neon Sign Transformer. The reason that these are used is because they
are shunted - i.e. they will only put out a limited current. Seeing as much
of the tesla coil circuit is a complete short current limiting stops you
from burning out transformers, blowing fuses, tripping breakers, etc. A good
reccomended value to start off with is 9000V or 9KV, at 30mA or 0.03A. This
is usually written as a '9/30 NST'. These may be hard to get hold of... ask
the list, or email Dave Mills dave-at-webshed-dot-org

Secondly you need to find some capacitors. I would reccomend starting off
with something called an MMC bank. This is a collection of low value
capacitors connected up to give you one much larger capacitor. One word of
warning is that these are lethal when charged, so you will need to put some
resistors across each capacitor. I reccomend that you use seven 0.068uF
1.6KV capacitors in series, with 10megohm bleed resistors across each onle.
If you ask nicely I'm sure someone would be able to sell you some
capacitors. Coilers generally call capacitors 'caps' for short. Ask Steve
Crawshaw stephen_crawshaw-at-tesla94.freeserve.co.uk

Thirdly you need to buy some magnet wire. This is thin solid core copper
wire with an insulating coating. You can but yhis from places such as
Maplins, and motor winding shops. You will need 28AWG wire, and you will
need to wind about 1000 turns on a piece of 4" by 16" piece of pipe (this
will cover a good 12 inches of the pipe). Then you will need to varnish the
pipe with PU varnish. A good pipe material is PVC which will work well for a
small coil, or a bit of 4" sewer pipe. Wind it carefully with no crossed
links and no gaps for maximum efficiency.

You then need to wind a primary. This usually consists of a flat plane wound
coil of *thick* wire or pipe. You will need about 15 turns of wire on your
primary to get the right tuning. Connect one wire to the inside end of the
coil, then move the other wire around the coil itself to get the right
tuning. Look for about 6 turns. This is usually the hardes thing to build
out of the lot, because it is very difficult to bend copper pipe through
small angles.

You then need to make a spark gap. There are many designs for this, but by
far the easiest is a multi segment gap. take a look at
http://www.powerlabs-dot-org/coil2.htm for more details on construction.

Finallly you need some high voltage insulated wire. You can use wire from
neon sign shops, but make sure the wire is rated at the voltage that you are
going to use, or higher.

There are some other bits and pieces that you can build such as terry's RF
filter (http://www.hot-streamer-dot-com), and you can use a variac to vary the
input voltage + current.

Remember that HV is dangerous and a 9/30 WILL kill you if you mess around
with it... i'm sure you know that already. The most dangerous part of the
system is the cap bank, because it will remain at HV after everything is
switched off.

Everyone else, if I have missed anything out... please ammend ;)

Be safe
Jason jasonp-at-btinternet-dot-com