Re: Magnifier conversion

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

Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>

Hi Antonio,

At 11:17 PM 5/3/2003 -0300, you wrote:
>Tesla list wrote:
> >
> > Original poster: "Terry Fritz" <teslalist-at-qwest-dot-net>
>
> > The model says I get 3% more RMS voltage this way and the actual test gives
> > 6% more voltage!!
> > http://hot-streamer-dot-com/temp/NewMag/0503-02.gif
> > So th conventional coil gives 50.54Vrms
> > http://hot-streamer-dot-com/temp/NewMag/0502-05.gif
> > The 2,3,4 magnifier gives 49.55Vrms
> > http://hot-streamer-dot-com/temp/NewMag/0502-07.gif
> > And the no C2 magnifier gives 56.01Vrms
> > http://hot-streamer-dot-com/temp/NewMag/0503-01.gif
> > I wonder if rather than having a mode that gives the highest "peak
> > voltage", a mode that gives the highest top terminal RMS voltage is our 
> goal??
>
>I am not sure if these simulated RMS voltage are meaningful. They
>apparently are calculated by squaring the voltage, low-pass filtering
>the result and taking the square root. Since the signal is not
>periodical, what is read depends on how the low-pass filter is.
>And the filter appears to be slower in decaying than the signal.

In this case, both the scope and MicroSim model are taking the RMS value 
over the displayed full 200uS time span.  So they should both be pretty 
representative of the power in the first 200uS.  There is also the "cycle 
RMS" that is just over one cycle but that would not have meaning here.  One 
problem is that it is unlikely that the 220K + 4pF streamer load is really 
that consistent in such a small time frame.


>When C2 is below the calculated, the system operates close to a
>mode that admits elements similar to the originals, except for
>C2. The magsim program can produce a table where possible candidates
>can be observed. For my system, the best combinations above the
>designed mode 3:4:5 are 6:7:14, with C2=24 pF and 7:8:21, with
>C2=14 pF. The first agrees quite well with what I observe, that
>is essentially a distorted mode 6:7, or a bit more, for two coils.
>With C2:
>http://www.coe.ufrj.br/~acmq/tesla/mag345v1l.jpg
>Without (lumped) C2:
>http://www.coe.ufrj.br/~acmq/tesla/mag345c2l.jpg
>Losses in both cases look the same.
>Note that the two coils system that I made with the same resonator
>operated in mode 6:7 only with an Oudin coil assembly. Normal
>operation was in mode 7:8 to 8:9. Even the distributed C2 still
>contributes to accelerate the energy transfer.

One problem is that the models do not adjust the coupling too.  There can 
be a lot wrong with my data.  But at least it gives me an idea where to go 
and a better idea of what is going on.


> > Yes,  This is all clean laboratory stuff right now.  The truth is in the
> > sparks ;-))  I note that the models and the real system have a little
> > frequency error.  I should probably go back and check the distributed
> > capacitances to tune things in more between the model and the scope
> > readings.  But the "no C2" case seems to give much better results RMS
> > voltage wise...  That would also match what the other magnifier builders
> > have often reported.
>
>C2 accelerates the energy transfer in any way, although just a
>discrete set of values produce efficient energy transfer (actually
>just one value produces perfect energy transfer, but other values
>get close enough). What may happen is that eventually gap quenching
>becomes difficult, and the rise in the maximum output voltage by
>having the "best" C2 is not enough to compensate. A high-power test
>can reveal what happens. In my system, what I saw was no quenching
>and something eating all the energy quickly (I will still look at
>this more carefully). Possibly the corona around the plates of my
>C2, or just the many streamers in my pointy top load. Without the
>lumped C2 the output was ringing for more time, producing better
>streamer output.

I think I have pretty much studied the systems enough with the signal 
generators to have a good idea of what to look for now.  I have the driver 
system all fixed again so hopefully it will be good weather tomorrow to 
drag it all outside.

Time for some real testing with real voltages again ;-))

Cheers,

         Terry


>Antonio Carlos M. de Queiroz