Re: Source for Aluminum Spheres (up to 12" threaded)

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

Original poster: "Gerry Reynolds" <gerryreynolds-at-earthlink-dot-net> 


 > Original poster: Ed Phillips <evp-at-pacbell-dot-net>
 >
 > Tesla list wrote:
 >  >
 >  > Original poster: "Mccauley, Daniel H" <daniel.h.mccauley-at-lmco-dot-com>
 >  >
 >  >  >      Has anyone here ever compared large spheres with toroids for
top
 >  >  > loading of high-power TC's?
 >  >  >
 >  >  > Ed
 >  >
 >  > Toroids do much better than spheres.  I believe the first person to
 >  > start using toroids was back in the 1970's from
 >  > what i've read from Richard Hull's historical notes.
 >  >
 >  > Dan
 >
 > In what way better?  Clearly they work just fine but wonder what their
 > edge is over a sphere with the same breakdown voltage.
 >
 > Ed


One way I can think of is that a toroid gives you mostly independent control
over the breakout voltage and topload capacitance.  The major diameter
mostly controls the topload capacitance.  The minor diameter mostly controls
the breakout voltage.  With a sphere, you don't have this level of control.

Gerry R
Ft Collins, CO