[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Vortex gap loss measurements


This is a very interesting experiment. First, when you
measured the slope during the ring down, did you see
the same size decrement of each succesive oscillation?
Is this what you mean by linear as oppossed to
logarithmic? Traditional wisdom purports that the
decay is according to V(t)=V(i)e^-rt where V(i) is the
forced initial potential on the capacitor. Your
results are very interesting however in that it flies
in the face of convention. The derived equation must
be something like V(t)= V(i)*-krt. I wonder if without
the secondary it is linear due to resistive losses
only. Without the secondary the additional absorption
of energy via the secondary mutual inductance is
missing which accounts for the linear decay? Also what
I found interseting was that with the gap distance the
slope remained constant. I would have expected greater
gap resistance at further distances but it seems that
the plasma provides a constant resistance no matter
how wide the spark gap is set (within reason of
course-I 'm sure at a foot the resistance would be
substantial as compared to 300 mil).

Also, does your scope generate a data file? If so, can
you share it?

--- Tesla list <tesla-at-pupman-dot-com> wrote:
> Original poster: "Lau, Gary" <Gary.Lau-at-compaq-dot-com> 
> Today I found some time and performed a comparison
> between the gap losses of
> my single vacuum gap, and my new single vortex gap. 
> To do so, I scoped the
> primary ringdown with no secondary in place.  I used
> a Terry Fritz fiber
> optic voltage probe across the primary coil and a
> digital storage scope to
> record the results.  I have not yet accurately
> calibrated the voltage
> readout, so for now, the results are just relative
> to each other.
> With no secondary in place, the ringdown is a
> linearly decrementing
> waveform, not logarithmic.  As such, the slope of
> the ringdown indicates the
> losses in the circuit and is independent of the gap
> firing voltage.  I
> performed ringdown slope measurements at a variety
> of gap widths to vary the
> initial voltage, but the ringdown slope is a
> constant, independent of Vgap.
> The power to the blower motor is varied through a
> lamp dimmer and I tried
> varying the motor speed to see what effect that had.
>  At very low speed, the
> linearly decrementing waveform became slightly
> logarithmic-looking, but
> still predominantly linear.  The gap breakdown
> voltage appeared to change
> slightly at low speed, but this was hard to measure
> as it was slight and the
> bang-to-bang gap breakdown voltage is not as
> consistent as one might hope.
> The slope decrement figures are assuming that my
> probe is accurately
> calibrated for voltage, though I suspect it may not
> be, so the figures are
> useful only for relative comparison purposes.  
> The pressurized vortex gap decremented at 200V/usec.
> The vacuum gap decremented at 235V/usec (17.5%
> faster).
> The vortex gap breakdown voltage is about 20% higher
> than the vacuum gap at
> the same gap distance.
> Vortex gap web page: 
> Vacuum gap web page: 
> http://people.ne.mediaone-dot-net/lau/tesla/onegap.htm
> <http://people.ne.mediaone-dot-net/lau/tesla/onegap.htm>
> Regards, Gary Lau
> Waltham, MA USA

Do You Yahoo!?
Yahoo! Mail - Free email you can access from anywhere!