Re: Solid State Tesla Coil Book Available

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

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

Gary Johnson wrote:

>  http://www.eece.ksu.edu/~gjohnson

Nice work.  

In 6-31 you write:

> It would appear that Rdie decreases as 1/w ...

I don't see any problem with this, since you've defined it as an
equivalent series resistance which represents the shunt conductance
due to dielectric losses. To do this you've taken the loss resistance
in conjunction with the capacitance Ctc.  With loss factors and caps
fixed, as w increases, Rdie must decrease in proportion for the 
product Rdie w Ctc to remain constant.

So an Rdie proportional to 1/w just means a constant loss factor.

Interesting stuff about the effect of humidity.  In view of the
rapid variation of (DF)water with frequency, it would be nice
to observe the ratio of Q factors of two modes, say 5th overtone to
fundamental, as the humidity varies.  The higher mode Q should 
deteriorate rather less with humidity than the fundamental.

I guess that would call for one of those coil-in-a-bag experiments.

Table 8 (6-32) suggests that lower frequency coils (16b, 22b) are
more susceptible to humidity effects. You blame the polyethylene but
is that really the case?  Wouldn't this be expected from your
analysis?  After all the (DF)water doubles on going from 150kHz to
300kHz, and in view of the much lower loss factor of PE compared with
PVC (ten times lower) then we would surely expect 22B to do badly
compared with 22T, without accusing the PE of excessive absorption.

I especially like section 4 of chapter 6.

Cheers,
--
Paul Nicholson,
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