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Capacitance distribution along the secondary inductor

Hi all,

	The question has come up as to how the capacitance along the secondary
really IS distributed.  I reprogrammed E-Tesla5 to cut the coil into 10
sections and compute the capacitance of each section.  This was done by
setting the voltage one a given section to what it normally is and setting
the rest of the coil to zero volts.

Section	Capacitance
1		0.0234
2		0.0550
3		0.1216
4		0.1595
5		0.3433
6		0.5482
7		0.5922
8		1.1191
9		1.6853
10		3.6935

Total		8.3411

Actual Total	8.3423  (when whole coil is calculated)

Amazingly, the sum of the sections adds up to the whole coil calculation
with an error of -0.0144%.  The small error "may" be due to the programs
"grainy" internal summation loops.

This took about 15 trillion machine operations!!  Many thanks to Robert
Jones for a number of tips on this.  Hard to say if this is right or wrong
but it is definitely the best "guess" I have.  It's late so I have not
graphed the numbers or contemplated any great meaning to them but this is
what E-Tesla5 came up with...

The only possible "fudge factor" is the voltage distribution along the coil
which is equation matched to actual testing.  But this distribution matches
the "Malcolm's ruler" profile.  It is interesting to not that the equation
used does not have any odd factors in it but is totally based on the coil
dimensions...

The coil calculated is:

1180 turns
#24 wire (0.201 inch dia.)
4.25 in dia.
26.125 in long.
22.1 mH

It is 1 inch above a ground plane in a room 80 inches high and 80 inches wide.


Cheers,

	Terry