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Two strange things my testing has found???




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From:  Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent:  Wednesday, March 11, 1998 4:49 PM
To:  Tesla List
Subject:  Re: Two strange things my testing has found???

A quick note:

> 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

I have just spent a few hours scoping and photographing a magnifier 
and associated parts of its system. I note from the primary exactly 
that of which Richard speaks in his second paragraph. I also note (in 
this particular system) that on expanding the timebase right out, the 
leading pulse has a ring of about 8 - 9 MHz superimposed on it. I 
also noticed a very definite DC bias in the resonator output. The 
scope was set to DC and has a DC load of around 10MOhms on the probe 
tip (it was positioned about six feet away from the resonator to 
reduce interference from primary goings-on).
    I have another post to make on these experiments that makes 
somewhat depressing if interesting reading. I was hoping for 
something special from the magnifier but it seems my hopes have been 
dashed somewhat. The experiments are not yet finished. I have taken 
extensive photos of scope traces under various loading conditions for 
further analysis.

Malcolm