Spherical vs. toroidal top loads on tube coils

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

Original poster: "David Speck by way of Terry Fritz <twftesla-at-qwest-dot-net>" <dspeck-at-relex-dot-com>

I'm pondering the construction of a tube coil using a pair of 833As, and a
roughly 4: diameter
x 24" long secondary.  I've noted that several current VTTC designs use a
small toroid on the
secondary, just like a SGTC.

I don't happen to have a small toroid at the moment, but recently ran
across a fine spun
aluminum sphere about 7" in diameter.  Does anyone have any idea how a
spherical topload would
compare to a toroidal topload of the same general size?  Is there any
reasonable chance of it
working?

Thanks -- I'll look forward to hearing any ideas about this.

Dave