RE: PC board primaries

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

Original poster: "Pete Komen by way of Terry Fritz <twftesla-at-qwest-dot-net>" <pkomen-at-zianet-dot-com>

What I see as a problem is that the flat trace on a flat board makes for a
physically large primary and a lower inductance than other arrangements.  A
flat strip of copper on edge and coiled in the normal fashion for a flat
spiral primary would have greater inductance and smaller size (and a would
likely have corona on the small radius edges).  Several layers stacked could
fix low inductance and size problems.

On the other hand, for a small coil at low power it could make a nice
looking primary.

I would like to hear results if you try it.

Regards,

Pete Komen

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Sunday, December 09, 2001 7:45 PM
To: tesla-at-pupman-dot-com
Subject: RE: PC board primaries

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

One problem I can see is corona between the innermost turn and the
secondary base.  A PC trace has a pretty sharp edge.

Gary Lau
MA, USA

> > Original poster: "Jim Lux by way of Terry Fritz
<twftesla-at-qwest-dot-net>"
> <jimlux-at-earthlink-dot-net>
> >
> > Has anyone ever tried making a flat primary by etching a piece of
copper
> > clad board?  With suitable copper thickness, the AC resistance might
not
> be
> > all that bad (skin effect, and all).  Say you etched  a 1/2" wide
spiral
> > trace... 2 oz copper is 0.007112 cm  Skin depth at 300 kHz in copper
is
> > around 0.01 cm..  Double sided board, with the spiral on both sides,
might
> > have a decent cross sectional area.