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Two strange things my testing has found???





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From:  richard hull [SMTP:rhull-at-richmond.infi-dot-net]
Sent:  Monday, March 09, 1998 5:40 PM
To:  Tesla List
Subject:  Re: Two strang things my testing has found???


>>----------
>>From:  terryf-at-verinet-dot-com [SMTP:terryf-at-verinet-dot-com]
>>Sent:  Saturday, March 07, 1998 10:47 PM
>>To:  Tesla List
>>Subject:  Two strange things my testing has found???
>>
>>        I have been looking at voltage and current waveforms now for a few
>>days with my VI probe and there are two issue I would like to request
>>information on.
>>
>>        First-  The output terminals of my 15000 volt, 60 mAmp neon
>>transformer seem to have about 150pF across them internally (like a big
>>parasitic capacitance).  This is causing some current spikes with certain
>>input filter circuits.  Other filter circuit do better because of this.
>>Anyone ever ran into this before????
>>
>>        Second- Just before the primary spark gap fires there is a little
>>current pulse I am seeing.  It is about 10% of the real initial pulse but it
>>has opposite polarity.  Very strange.  I far as I can tell the pulse is real
>>and not a glitch or anything.  It seems to almost always be there.  If
>>anyone has any information on this I would love to here your thoughts.  I
>>will try to get a picture of it on my web page
>>(www.peakpeak-dot-com/~terryf/Tesla/Main.html) ASAP.
>>
>>        I have made a number of improvements to my system and it is working
>>very well :-)  My spice models and the actual results now show excellent
>>correlation since these improvements.  The little spark gap pulse does not
>>show up in the models.  However, I use perfect switches and such in the
>>models.  This may be hiding something that happens in real systems like this
>>pulse.  I have completely overcome the bandwidth issue with redesigned
>>transducers.  Now even the voltages and currents show perfect 90 degree
>>phase differences and the levels are all correct! I will write up more
>>information as time permits.  I am working on detailed planes for the probe
>>and will publish them when the design is stable.
>>        I am begining to set up for real TC tests using this equipment
>>rather than the test circuits I have been using so far.  Now that I have the
>>VI probe working so well, it is time to really turn it loose. :-)) 
>>
>>Thanks
>>
>>        Terry
>>        terryf-at-verinet-dot-com


Terry,

You are probably seeing Tritchel pulses.  These are a form of precursor
pulse at low levels.  First noticed By Trichel in the 30's, they can
actually form a miniature CW oscillator if the gap is set just right.  As it
is the Tritchel pulse just brings on the break down of the main gap here.

Charles Yost and myself have been investigating the unique electrostatic
nature of the resultant signal.  Which is a classic ring down of the
resonator superimposed on a large decrementing DC potential.  Again, all
must be just so-so with no real gap break dwon in the classic sense.

Richard Hull,TCBOR