Re: 1500-3000 turn coils

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 9/7/00 12:14:59 PM Pacific Daylight Time, tesla-at-pupman-dot-com 
writes:

> Dan,
>  >
>  >As the number of secondary turns is increased, the number of
>  >primary turns has to be increasd also to keep the coil in tune
>  >using a given cap size, so the turns ratio stays basically the same.
>  >
>  >John Freau
>  >
>  >
>  >
>  John,
>  
>  my intution tells me that cap size and inductance is not a linear 
>  relationship. especially when you consider the outer turns of a conical or 
>  flat spiral coil...each consecutive turns affords more inductance than the 
>  previous.

Dan,

You're correct which is why I said *basically*.  In any case, 
I think the output voltage follows the inductance ratios more than
the turns ratios in a resonant air core transformer.

>  
>  aside from reduced sprak gap losses from more primary turns, are there any 
>  other areas that contribute to longer sparks associated with a larger 
>  primary? i had originally read that more turns in the primary allowed more 
>  effecient transfer of energy between the coils, or something about 
superior 
>  coupling (12-15 turns being the "sweet spot").

I don't see why the coupling should be superior, or the energy transfer
better, for any other reason than the reduced gap losses.  I've gotten
considerably better results using 20 to 35 turns in the primary than
using 12 to 15 turns.

John Freau

>  
>  dan