Re: Micro Tesla Coil design

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <dhmccauley-at-spacecatlighting-dot-com>



Actually, that is still a bit too large.  This size transformer shouldn't be
difficult to wind.  A simple E-core (non-ferrite) should do it at 60Hz and
per my ANSOFT
simulation, the primary only needs about 10-20 turns with the secondary at
about 200-400 turns for 20:1 to step-up.  Low current of course figuring
about 5-10mA at
1000V-2000V.

Dan



 > 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
 >   >
 >   >
 >   >
 >
 >
 >
 >
 >