Re: PVC or not

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

In a message dated 7/26/00 12:28:56 PM Pacific Daylight Time, 
tesla-at-pupman-dot-com writes:

> Original poster: "D.Wightman" <dwightman-at-mmcable-dot-com> 
>  
>  concerning secondary coil forms,,it seems that there is lots of coilers 
> using
>  pvc for sec coil forms,,yet we find lots of information that it is a high 
> loss
>  material? i am getting ready to build a 14 or 16 inch coil and have prices 
> for
>  acrylic and pvc..20 to 30 dollars (acrylic) versus 5 dollars a foot (pvc). 
i
>  plan on using the best inverter duty wire i can get.which will be close to 
> 300
>  dollars.. i do not want to have to wind the thing twice! my question is 
will 
> i
>  really notice a difference whether i use pvc or acrylic..thanks everyone  
:-)
> )
>  

D,

Although PVC is a high loss material, the losses do not really come
into play and do not noticeably affect the output of a TC.  The type
of wire you use on the secondary will not noticeably affect the output
either.  Secondary losses are very minor.  Most of the losses are in
the spark gap.  By using thinner secondary wire (more turns), you
can use more turns on the primary, which increases the primary
surge impedance which will lower the gap losses and give longer
sparks.

Cheers,
John Freau