Re: dazed and confused.

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

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

Tesla list wrote:

>Original poster: "Cajun Coiler by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<cajuncoiler-at-cox-dot-net>
>
>
>Ok, I'm getting a bit confused here, as to properly designing a tank
>circuit...  When I query WinTesla about my NST (15/30), it says I should
>use a capacitor of .0053uF.  However, when I plug that value into the
>section for figuring the primary, it only matches up with that capacitance
>when there is like 38 turns (1/4" copper tubing, flat spiral).  Yet, most
>of the systems I see using this size NST, and this primary material, have
>somewhere between 6 and 16 turns on the primary.  What am I missing?
>Someone please let me in on this secret quickly, as I can almost HEAR my
>IQ level dropping from the confusion.
>
>---
>C.L. Mayeux
>Owner, MSB Data Systems
>poohbear1961-at-cox-dot-net
>http://www.msbdatasystems.tk
>
>
>
>
>
Hi CL...

Some of the constraints in coil building are
1. cap size  ( most coils are set by the available cap size and transformer)
1 1/2. transformer  ( you already have that   use wintesla to find the 
approximate cap size rating for the transformer you plan to use   as you 
mentioned ...   .0053 will be the resonant size   build for 30KV if you 
are doing MMC  ) 
2. primary size ( as you mentioned 6 -18 turns are nice ... 55 a bit big)
3. toroid size  ( too big and no breakout   too small and its short 
streamers)
4. secondary size ( this isnt too much of a problem, lots of available 
coil forms out there and 22 Ga. wire is easy to find)

depending on ones budget, the cap size and transformer will need to be 
"matched".  the transformers power out will have to be enuf to charge 
the cap to almost full between cycles.
since you are using  a 15/30 ...  a cap of .005 uF -at- 30KV will be a good 
choice

size constraint #2 ...  primary size...  in smaller coils a primary with 
10 - 18 turns seems to be most efficient try that design in the Wintesla 
and tweek the secondary parameters to get the cap size to coincide.

toroid size ..   on average, the min dia. should be about the same as 
the secondary tube dia, the major dia should be about the same as the 
length of the secondary -  10 - 20% ( this is just a general rule of thumb)

I did a quick set up for a 15/30 with a .005uF cap 1/4" Cu tube primary 
with .25" spacing 30 degree cone , 3 X 18 22ga wire secondary with a 
3X15 toriod ....   primary needs approx. 10 turns to tune...

hope this heped....

Scot D