Re: component sizing

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

Original poster: "BunnyKiller by way of Terry Fritz <twftesla-at-uswest-dot-net>" <bigfoo39-at-telocity-dot-com>

Tesla list wrote:

> Original poster: "The Backs by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<tcback-at-cbpu-dot-com>
>
> I am in the process of building my first coil and I have a few questions.
>  The secondary is 10.25" diameter on a PVC pipe.  It has about 916 windings
> of 20GA wire.  For the Primary, I am planning on using 1/4" copper tubing
> wound at a 15 degree inverse conical. the spacing between winding on the
> primary is 1/2".  I have not "wound" the primary yet, but I was planning on
> 15 windings.  but I have notches in my supports for up to 17 winding. I
> currently have 1 15/60 NST that I am planning on using to power it, but I
> was going to try to get at least two more of them.
>
> Now for the questions.
>
> 1.  From Ed Sonderman's Excel spread sheet I was planning on trying to get
> a tank cap with a value of around .028 uF.  Does this sound correct, and if
> so, what is the best way of obtaining the tank caps?  I have a limited
> budget, but I am also trying to make a very nice looking coil.

go for the famous MMC style cap very versitile and adjustable if designed right

>
>
> 2.  I wanted to make a RSG.  I have access to some DC motors and
> controllers, but I have seen a few places mention that an async-RSG is bad
> news for NST's.  should I stay away from the DC motors?
>

dc are usable but while adjusting of the rpms, this can be bad for the NST.
 go for either a
modified AC 1725 rpm motor or find a 1800 rpm AC motor

>
> 3.  I have some 1 1/2" acrylic that I was planning to use for the rotor of
> my RSG.  I am planning on drilling and tapping 1/4-20 holes in it and using
> threaded rod with acorn nuts on the ends for my electrodes.  is this a good
> plan or bad?
>

1.5" thick stock is a bit heavy, you will need about a 1/3 or better hp
motor to spin it up to
speed. most people use 1/2 - 1/4 " material for the disc. the electrodes
should be about 3/4 -
1" long on eac side of the disc, acorn nuts are a bit short.

>
> 4.  RF chokes.  what are some good designs, and How do I size them?
>

check out Terry's web page for RF filter circuits...  hes got an excellent
desing there

>
> 5.  what is the best method of constructing a toroid that would be large
> enough for my coil?
>

for a 10" dia secondary you will need a toroid of at least 8" (height) X
40" (width)..also a
15/60NST will have a difficult time supplying enuf power to really do
justice for a coil of
this size.  Consider making your secondary about 8" dia X 24-32" tall ,
this will be more
compatible with your NST.

>
> Thank for your help
>
> Tom Back

Scot D