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Mini coil advice?



Here is my design for the mini coil I am building.
I have a few questions tho..
Thanks for any input you have!
---------------------------------------------------
Transformer:
  Voltage        : 3.5 Kv
  Current        : 3 mA
  Impedance      : 1166666

Primary Cap:
  Capacitance    : 0.002274 mF
  Reactance      : 48.6
  --Constuction
    Plates       : 2
    Dielectric   : Glass ( K=~6)
    Area         : ~1.7 in square

Secondary:
  Turns        : 650 ( 36 AWG )
  Height       : 4.5 in
  Width        : 1 in
  Res Freq     : 1.44 MHz

Primary:
  Turns          : 13
  Inner diameter : 0.75 in
  Outer diameter : 2 in
  Width          : 1.25 in
  Req Inductance : .00537 mH
  Ind. -at- turn 9  : .00533 mH
---------------------------------------------------
1) Why are the transformer impedance and cap
   impedance supposed to be equal?
2) Did I get the current correct on the xfrmer?
   the output appears to be 3.5 Kv and it is rated
   for 10 Watts.
3) Do I need to protect the xfrmer from inductive
   kickback or something?RF choke? Safety gap?
   There is a ceramic disk cap across the output
   of the secondary on this xfrmer, what is it for?
4) The res freq calc is based strictly on the length
   of wire used in winding the secondary, is there
   a better way to estimate the value( without the
   use of a signal generator )?  I have a 'scope.
5) When I put on a discharge terminal, how do I
   determine what the new res freq is? Just move
   the tap around and watch the output?
6) This is the tank config I was planing on, should
   I wire it exactly as shown, or do I need some other
   components( xfrmer protection )?

     120v   3500v             O
     60Hz   60Hz              O Secondary
     ----O||O--------o o--  O O ( fired on
         O||O     |      |  O O   counterpoise )
         O||O     |      -->O O
         O||O     =         O O   -o o-  : Spark gap
         O||O     |         O O   =      : Primary cap
         O||O     |         O O   O      : Coils
     ----O||O---------------O O

7) Do I need more than one gap in series?  What
   should I set the gap spacing to?
8) If I do need some kind of RF choke, what can I
   use?  Will the secondary on a dead transformer
   work?  How can I tell if a homemade RF choke is
   effective without risking my xfrmer?

Thanks again!
David Knaack
South Texas