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RE: Vortex gap loss measurements

If I may reply to my own post, I've had some further thoughts on the
observed variability of my gap breakdown voltage:

		>>I would think that your voltex gap might quench a little
better than
		>>the vacuum gap too, since I think pressure helps quenching
		>>reducing losses.  Interesting too about the variable bang
size and
		>>variable voltage gap breakdown in the static gap....

		>I just thought of something.  The scope triggered on the
rising edge of the
		>ringdown.  If the cap was charged in one polarity, the
scope will trigger on
		>the first cycle.  The other 50% of the time when the cap is
charged in the
		>other polarity, it won't trigger until one (decremented)
cycle later.  This
		>may explain it!  I wish I could think of a way to always
trigger on the
		>first ringdown edge.

After sending that, I realized that I'm using a digital storage scope, which
also captures an arbitrary amount of pre-trigger data.  If the initial
ringdown voltage were really consistent, then I would have seen it, with
jitter on the trigger point.  So I think the variability is real.

Here's another possible explanation.  This is a static gap and as such, the
bang-to-bang period is very irregular.  It was probably more irregular than
usual during my experiment because I brought up the variac just enough to
get the gap to fire at the slowest possible rate.  I think that the density
of ions in the arc channel diminishes with the time since the last bang, and
with fewer ions, the breakdown voltage is higher.

Regards, Gary Lau
Waltham, MA USA