RE: Micro Tesla Coil design

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

Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Gary.Lau-at-hp-dot-com>

Rolling your own HV transformer is certainly not my idea of fun.  Larger 
bug zappers typically contain a 4kV/9mA or thereabouts current limited 
transformer somewhat larger than your fist.  I should think that would be a 
good fit for a palm-top coil.  They're pretty common at flea markets 
(more-so in the summer), and ebay generally has many.

One thing to watch though is some bug zapper transformers (BZT's??) have a 
potted secondary winding (a good thing), but within the potting is a 
ceramic cap, in parallel with the secondary (bad), to zap the bugs that 
much harder.  You may need to do some precision drilling to remove that. I 
haven't yet looked at how easy it is to remove the current limiting shunts.

Gary Lau
MA, USA

  > Original poster: "Mccauley, Daniel H by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>
  >
  >
  >
  > I'm soon to start designing a microcoil.  The goal of this project is
build
  > a conventional tesla
  > coil as small as possible and still work.
  >
  > Has anyone had experience building one of these things? I know I saw
someone
  > building a palm sized version
  > on the internet before, but have long ago lost that link.
  >
  > Some questions:
  >
  > 1.  I'm going to have to build a mini 60Hz step-up transformer from
scratch.
  > What should the minimum voltage
  > output on this be?  I was thinking of having at least a 1kV to 2kV output
at
  > 60Hz.
  >
  > 2.  Ballasting:  Since this transformer will not have current limiting,
what
  > type of ballasting could I get away
  > with.  I guess at this size (and at the sacrifice of a few volts) I could
  > use a resistor or even wind a small
  > inductor on the primary side of the transformer.
  >
  > Dan
  >
  >
  >