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Re: An Important Post.
From: FutureT-at-aol-dot-com[SMTP:FutureT-at-aol-dot-com]
Sent: Tuesday, August 05, 1997 4:19 AM
To: tesla-at-pupman-dot-com
Subject: Re: An Important Post.
In a message dated 97-08-05 02:35:44 EDT, you write:
<<
> From: Malcolm Watts[SMTP:MALCOLM-at-directorate.wnp.ac.nz]
> Sent: Monday, August 04, 1997 7:22 PM
> To: tesla-at-pupman-dot-com
> Subject: An Important Post.
>
Malcolm,
Very nice work. Yes, this suggests that a magnifier is quite similar
in operation to a regular 2 coil system, except for the close coupled
driver, and magnetically separated resonator.
I was under the impression that the Corums consider BOTH the
two coil system and the magnifier to be distributed, NOT lumped.
They did say something about the operation being lumped while
the gap is firing, and distributed after the gap quenches. As we
know, most of the energy is transfered to the secondary while the
system is coupled. The Corums suggested that Lou Balint's
Twin Peaks Dual Resonator magnifier (two different L resonators,
capped with one toroid) should obey distributed WSWR rules.
But the system did not seem to follow these rules, but followed
lumped constant rules instead.
Duane Bylund's work suggested that adding a large top terminal C
may make the resonator more lumped-like, and less distributed in
nature. Have you tried modeling the line with a large top-C added
to see if anything changes?
Nice data for understanding coupling, and how the resonator
"tolerates" the shorted turn toroid.
Just a few thoughts,
John Freau
>Dear list,
> This morning I have made a breakthrough that I count as
> the most important piece of research I have ever undertaken. I have
> produced a model of a TC resonator using lumped components in an
> artificial transmission line and measured it. The paradoxes that have
> puzzled so many for so long are now explained and verified in
> experiment!
> The Experiment: The goal was to model the resonator accurately using
> real world components in such a manner as to allow *direct*
> measurement of its attributes. Moreover, the model had to agree with
> the formulae we use to predict frequency etc, most notably the lumped
> ones (e.g. Wheeler, Medhurst). After mulling over the results of line
> experiments done in the last two days, it appeared that appropriate
> grading in the line was needed to get the lump calculated frequency
> to agree with the measured resonant frequency and so it proved to be.
> Apparatus: A seven stage line was built as follows:
> 1.6mH 800uH 400uH 200uH 100uH 50uH 25uH
> ----oooo--+--oooo--+--oooo--+--oooo--+--oooo--+--oooo--+--oooo--+---
> In | | | | | | | Out
> --- --- --- --- --- --- ---
> --- --- --- --- --- --- ---
> Gnd | | | | | | |
> ----------+--------+--------+--------+--------+--------+--------+---
> 10pF 22pF 50pF 100pF 220pF 470pF 1000pF
>
> Caps are silvered mica jobs. The inductors are airwound on bobbins
> for the popular FX2239 potcores.
>
> Results: Measured f = 65kHz +- 0.2kHz
> Calculated f = 65kHz near as. Done by summing inductances and
> capacitances and using standard 2PISQRT(LC)^-1
> Most of the 90 degree phase shift along the line occurred in
> the first stage as did the bulk of the voltage rise. This is
> not surprising since half the total inductance appears in this stage.
> Obviously the model needs to be made a lot more fine-grained to be
> real close to the real thing but serves as a good indicator
> nonetheless.
>
> Until I get a lo-Z sig gen onto it, I cannot measure Q or VSWR within
> to reasonable accuracy. The line loaded the el-cheapo generator was so
> heavily loaded that generator output sagged by over 75% at resonance.
>
> With this model is shown:
> - lumped frequency calc agrees with measured value despite the
> distributed nature of the circuit
>- grounding one end of a single layer solenoid alters it
> characteristics markedly from the normal lumped behaviour but
> preserves the lumped values all up. This is why we can measure L
> and f and calculate C and find it agrees with well tested formulae
> despite the fact that wired as a resonator, top L is almost non-
> existent and appearances suggest the resonator L should be less
> than the measured lumped value.
> - the resonator appears to match at resonance when terminated at each
> end by its calculated Zo (1.3kOhms) i.e. Vo = Vi to first order
> with a 90 degree phase shift from one end to the other (second
> order LP filter response at the turning point :)
> Future experiments:
> - use a more finely graded line to observe gradual phase shifts
> - use capacitive E transfer to measure Vo pk
> - measure Q and VSWR
>Some Implications of these results:
> - IMHO the Corum's analysis of the two coil system as being lumped is
> correct but for the wrong reasons. They claimed that because primary
> flux envelopes the whole secondary with minimal time delay, the
> coupled system can be treated as lumped (of course there had to be a
> reason - you can't ignore measurements). However, modelling by others
> in PSPICE and some elementary thinking shows this cannot be true. The
> primary is heavily coupled to the bottom portion of the resonator
>only. Witness the lack of effect of sticking a shorted turn (toroid)
> at the top of the resonator on the primary - pretty much
> unmeasureable in the primary. For that matter, it hardly affects the
> resonator either :)
> It is clear to me that conservation of energy must be observed in
> doing output voltage calculations in the resonator. IMHO, *estimates*
> of some MegaVolts output for very modest primary energy melts away
> entirely.IMHO, it follows from these results that Vo for a capacitive
> discharge situation should follow the rule Vo = Vi.sqrt(Cp/Cs). Many
> experiments in measuring single shot sparks have suggested this for a
> long time now.
> It follows that a free resonator must obey the same rules except
> for being free of magnetic coupling to the driving system. It follows
> then that conservation of energy must also apply to a free resonator
> in a pulse-driven situation because a finite amount of energy is
> available to charge the distributed capacitance. Until it is measured
> though, that is speculation on my part.
> All for the time being. Flames, comments and refutations welcomed.
> Malcolm
>>