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RE: Getting zapped by my unpowered Secondary

Original poster: "Ray Robidoux by way of Terry Fritz <twftesla-at-uswest-dot-net>" <robidoux-at-basystems-dot-com>

> Hello Ray,  I've never been zapped by residue electric charges in the way
> you described. Saran wrap is pretty thin stuff so I don't think it would
> hold off very high static voltages, but it probably would insulate you
> against 120V ac. I've been "zapped" by ac power which managed to find its
> way into equipment I worked on even though the power switch was off. This
> was because of poor grounding. Anyway, I always make it a point to UNPLUG
> before working on anything like TC's. Be careful and happy coiling.
> Chuck

Well first off when I grab the secondary, the power cord is UNPLUGGED so I
know it is not from stray AC leakage. Secondly, when I say I wrapped it in
Saran Wrap, I mean about 40 to 50 layers of Saran.

Also one thing I did when I wound my coil was to apply 3 strips of double
sided scotch tape to the form. I laid these out lengthwise on the form to
help hold the wire in place as I wound the coil. This was a fantastic help
in holding the wire, but I wonder if this tape may not be the dielectric
that may be holding the charge that I am experiencing now. BTW my coil
form is a thin cardboard tube 2.5" in OD, treated with Thompson's
and shellac. The finished coil was then sprayed with polyurethane.

The reason for my question is not to prevent pain to myself, BUT to
what is going on. The secondary circuit is formed by the Ls of the coil an
Cs of the self capacitance of the coil and topload combined. If I and some
are getting zapped and still others are not. Then something in our
methods are producing coils with larger and smaller Cs from person to
Knowing what makes this difference and which differences are better than
is what this question is all about.

So perhaps the question needs to be changed slightly to ask, what
methods produce zaps and which do not.