Re: self capacitance of flat and conical secondaries

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Antonio Carlos M. de Queiroz" <acmdq@xxxxxxxxxx>

Tesla list wrote:
> Original poster: Mike <megavolts61@xxxxxxxxx>
> Hi Terry, all,
>      Terry, you provided links to so good info for a recent post, 
> but I'm considering winding a flat spiral secondary and can't seem 
> to find an equation to estimate that in a flat spiral or conical 
> coil. Does anyone have such information?
> Thanks,
> Mike

An estimation can be obtained from the capacitance of a flat disk,
that is C=8*e0*radius.
e0=8.85e-12, radius in meters.
Considering that the "self capacitance" of a cylindric coil is very
close to one half of the capacitance of a cylinder with the same
dimensions, one half of the capacitance of a disk shall be close to
the correct value. Maybe 3/4 of it if the output is at the edge,
or 1/4 if the output is at the center, considering the different
areas of the inner and outer halves of the coil.
Could someone verify?

Antonio Carlos M. de Queiroz