Pictures from builders using Nut's & Volts Halloween article.
(Reprints available by writing to

Taking good pictures of sparks is difficult, but you guys have done it again!!!!

The classic "bolt" of electricity when the coil is run with a neon sign transformer.  The bolt you see is usually thick and quite loud.
Note that despite the increased power from the NST (as opposed to the smaller input transformers mentioned in the article) the spark length did not increase with this coil exponentially.  However, as you can see, the character and energy of this spark is a whole new animal!

I lost the address of the talented builder who constructed this coil.  I'll post it as soon as I hear from him again.

This coil was built by Robert C. Powell (  As you can see, the PVC form was extended, and the coil was built to be cleverly concealed beneath a table.  As "Trick or Treaters" approached, the coil was fired arcing sparks to items on the desk and to the candy!
I'm told that the high frequency "skin effect" was also used to the delight of many "Trick or Treaters" as well.  :-)


This coil was built using the Nut's & Volts article as a starting point, however using the software and ingenuity builder Terrill Spotanski  ( added a torroid and other touches to the design.  Look at those BEAUTIFUL streamers in the close up shot!  Great photo Terrill.




                        Mylar balloon meet Tesla coil, and streamers from my 250k coil...


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