Re: H/D Ratio

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

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 1/20/01 11:47:13 AM Eastern Standard Time, 
tesla-at-pupman-dot-com writes:

> Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" 
<Leik3-at-aol-dot-com>
> 
>  
>  Hi All,
>  I have a 15/30 and my secondary is going to be 4.5 (o.d.) inches. I was 
>  planning on a h/d ratio of 4 leaving me with 18 inches of winding height. 
> Any 
>  comments on this?? Is it too large of a ratio, will my transformer power 
it 
>  with decent results?? I haven't wound it yet, so it's not too late to get 
a 
>  smaller form if necessary.
>  Thanks a bunch,
>  Dennis

Dennis,

I like the idea of a larger rather than smaller form.  You can put
more turns of wire on it, and probably get longer sparks.  My TT-42
coil uses a 12/30 NST, has a 4.2" by 19" form, and gives 42"
sparks and can be seen at:

   http://hometown.aol-dot-com/futuret/page3.html

For best results, use at least a 4" by 13" toroid, a 120 bps
sync rotary gap, and an LTR sized cap of about 14nF.

John