Re: First Spark

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

Original poster: FutureT-at-aol-dot-com 

In a message dated 9/10/04 9:06:59 AM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

>Original poster: "Rich" <rdjmgmt-at-socket-dot-net>
>
>Well my first try at a coil worked a little. It is 15Kv 30ma NST and the
>first try was at 8 ½ in.  I do have a question. Should the bottom of the
>secondary coil be even with the primary, above or below it?
>I had the torrid up too high at first, I had to bring it to where the
>lower side was just below the top of the secondary before I got any sparks.
>The torrid is 4” flex pipe mounted on a 12” x .032 alum plate, overall 
>20”
>dia.  Are there any hard and fast rules on setting the torrid?
>
>Rich
>


Rich,

There are only rough guidelines.  Usually the bottom of teh toroid can
be about 1" higher than the top of the secondary winding.  Of course
this depends on the overall size of the coil in question.  It's a
proportional thing mostly.  A coil that is overpowered by need
to have the toroid a little lower.  A smaller toroid can be placed
below the main toroid to permit the main toroid to be raised.
An example of this can be seen at my website at:

   <http://hometown.aol-dot-com/page3.html>http://hometown.aol-dot-com/page3.html

you may need to click on spark gap Tesla coils from that
webpage.  There's also a link to John Morawa's website that
shows a similar arrangement with a small toroid below the
larger one.

Regarding the height of the secondary relative to the primary,
this depends on the design and power of the coil.  Lower
the secondary until raising sparks occur, then raise the secondary
until the racing sparks stop.

Congratulations on your first light of your coil.

John