Re: Primary and Secondary winding direction

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

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <paul-at-abelian.demon.co.uk>

John Couture wrote:

> Tesla was interested in the 1/4 wavelength secondary and used it to
> find the optimum toroid (secondary terminal) of a Tesla coil.You can
> find more info by going to my web site and checking on
> "6. Optimum Toroid". 

John,

I took a look at your web page page, and if I understand correctly you
are suggesting that the toroid should be chosen to bring the resonant
frequency down to that of the quarter wave resonant frequency of the
wire length which was used to wind the secondary.

Perhaps you could justify this a little more, in view of the fact that
when the coil is wound, the inductances and capacitances which
determine the wire's resonant frequency are completely disrupted from
their straight line values as a result of winding, and thus the
original straight line resonant frequency of the wire seems to be of
historical interest only. I fail to see how it can have sufficient
relevance to warrant its use as a basis for toroid selection when in
view of energy storage the smallest possible toroid ought to be
desirable. In what sense is the performance optimised - not for output
voltage, obviously - and which performance measures deteriorate when
the toroid is increased or decreased from this optimum size?

Hopefully you can help me out on these points, otherwise I can only
label this notion as another of those Tesla myths since is doesn't
seem to have a sound basis. Could it be that Tesla used this idea at
one time as a working hypothesis, in the absence of anything better,
and never got the opportunity to refute it?

Regards,
--
Paul Nicholson,
Manchester, UK.
--