Re: Magnifer vs. Tesla Coil

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

Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net> 

 >  > statement
 >
 > How did you simulate the system? Paul Nicholson tssp programs can make
 > an accurate simulation. For more qualitative results it's possible to
 > simulate a discrete version with several LC sections, after estimating
 > proper values. A simpler model is an uniform transmission line loaded
 > by a capacitor.

Nothing anywhere near so big and clever as tssp. Just an equation for a
uniform shorted TM (telegraph equation for velocity) in parallel with C in
mathcad. Put together back when the lump 1/4 wave thing was a hot topic.
 >
 >  > As top load is  added the poles pairs shift to a lower frequency by
 >  > approximatly the same amount (ignoring dispersion) were as from at
least one
 >  > perspective the zeros do not move.
 >
 > I imagine that you are looking at the impedance seen at the output of
 > the system. In an analysis of a single coil (modelled as a transmission
 > line or anything else) loaded by a capacitor, the zeros of the output
 > impedance really don't move if the load capacitance is changed. This
 > must be in this way, because at the frequencies of the zeros the load
 > capacitor is short-circuited, and so its value doesn't affect the
 > zeros.

Thats what I figured.

 > Interesting observation.
 > Note that a coil loaded by a huge terminal capacitance is effectively
 > grounded at both ends, and so operating in "1/2 wave" mode. Additional
 > resonances are expected to appear around 2, 4, 6, etc. times the
 > fundamental resonance frequency, but it's difficult to "excite" them
 > because there are zeros very close to these same frequencies.
 > the modes (in the now nonlinear system) decrease even more.

I thought I would check it from a spatial perspective. The first pair of
zeros are a spatial 2/4 wave mode while the second pair of poles is a
spatial 3/4 wave mode. Both have the same polarity at the topend but over
the halfwave section they are opposite. As you add topload the spatial 3/4
wave mode is truncated so it approaches a halfwave but as the half wave
section has the opposite polarity to the spatial 2/4 wave mode it cancelles
with it.  Hence in the limit both disappear from observation.

 >
 > I was worried bout the effect of high-order resonances on magnifiers,
 > because if they are designed for modes a:a+1:a+n, n large, there is
 > a resonance at quite high frequency, easily above the main resonance
 > of the unloaded system. But I didn't observe anything evidently wrong
 > experimentally. The cancellation may explain why.

Yep the gold standard is good observation.


 >
 > Antonio Carlos M. de Queiroz
 >
 >
Bob