toroid height adjustment - what does it really do?

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

Original poster: "John Morawa by way of Terry Fritz <twftesla-at-qwest-dot-net>" <morawaj-at-interaccess-dot-com>


Hey everyone,

I am curious about what raising or lowering the height of the toroid
actually changes on a functional tesla coil.  What are we talking here?  A
change in the shape of the field (sending sparks in a different direction) ,
altered capacitance (and thus frequency) of the secondary system of a coil,
or what?  Obviously it increases the distance from the breakout point to the
primary coil and depending on your arc length may thus help reduce primary
strikes.  But what else does it really do???

Thanks much,
Curious John