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

RE: Vortex gap loss measurements

Gary -

Many thanks for providing us with your test data. More of this type of test
information is needed because there are still many secrets of TC operation
we need to know.

You mentioned that at times the dampened wave appeared to be logarithmic. I
found this to be true in some of my tests using a standard scope. However,
the traces were very irregular. Could it be that the storage scope is
affecting the results by sampling more than one trace?

John Couture


---Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Friday, September 01, 2000 6:17 PM
To: tesla-at-pupman-dot-com
Subject: Vortex gap loss measurements

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:



Regards, Gary Lau
Waltham, MA USA