Re: secondary core other than air

["Ed Phillips" <evp-at-pacbell-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Tesla list wrote:
> 
> Original poster: "Jim Lux" <jimlux-at-jpl.nasa.gov>
> 
> -----Original Message-----
> From: Tesla list <tesla-at-pupman-dot-com>
> To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
> Date: Monday, August 07, 2000 11:32 AM
> Subject: Re: secondary core other than air
> 
> >Original poster: "Garry F." <garryfre-at-pacbell-dot-net>
> >
> >I often thought the reason telsa coils were air core was because Ferrite
> >might not be capable of rapid magnetic change that would be required for a
> >high frequency app such as tesla coils. I think the atoms would not be able
> >to spring back into their original orientation once the magentic field
> >collapes fast enough.
> >
> >I could be wrong tho, but I tend to think this is why they reccommend only
> >non-magnetic wire as conductors in Tesla coils
> 
> Ferrites can certainly handle TC frequencies (I use them at 13 GHz).
> Actually at TC frequencies, you might want powdered metal cores... Ferrites
> are more appropriate for higher frequencies.
> 
> Insulation is going to be the issue.  You don't need more coupling (most
> TC's aren't coupled very tightly, and tighter coupling degrades performance,
> except for magnifiers).

	Ferrites would work fine, IF the area were big enough.  Even at
frequencies of the order of 200 kHz the area would have to be several
square inches to avoid saturation at the voltages at which TC's run.

Ed