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Re: That secondary behaviour, E-Tesla5, and Corum's thing...



Hi Ken,

At 11:03 AM 04/15/2000 -0700, you wrote:
>Terry & the rest-
>
>More wonders of the computer age!  I printed out your Web image & have it
>in front of me & it looks oh-so-familiar.  Except...the image I got on my
>scope just this a.m. doesn't have the fuzz--hah!, hah!, hah!

I have a few more computer wonders too.  You ain't seen nutin yet!! ;-)

My plane antenna probe needs about 250,000 volts to get a good
signal-to-noise ratio :-)

>
>What I did:  My ancient Wavetek 115 will emit a single sine cycle, at the
>>end< of its gate input from the HP 8005.  I made it do that, then synced
>the Tek 7904 from the beginning of the gate signal.  Thus, by choosing a
>long enough sweep time, I could get the 1 cycle event-time fully to
>appear on the screen.

Hmmmmm... "My" toys won't do that!  Grrrrr ;-))

>
>Next I adjusted the Tek's 7B92A dual time-base plug-in to display that
>whole 1-cycle time & a bit more all across the screen.  I displayed a)
>the input 1-cycle to the bottom of the secondary and b) the signal at the
>top via the 10:1 probe.  I left the probe galvanically connected to avoid
>phase shift due to unknown series capacitance were I to just lay it near
>(your point!).
>
>Now here's the fun part:  My 7904 incorporates a 7D11 digital delay
>plug-in.  It can make a little pulse & an intensity change appear on the
>screen, digitally positioned anywhere along the display.  So, I set that
>up & with it made the following measurements at resonance:
>
>A.  Commencement of the 1 input cycle, 0 us, normalized.
>B.  1st input peak, 2.7 us.
>C.  Input z.c. (zero crossing), 5.6 us.
>D.  2nd input peak, 8.3 us.
>E.  Input end, 11.0 us.
>
>F.  1st output z.c. (each z.c., eyeballed by choosing the place on the
>wave equidistant between 0 or a preceding peak and the following peak),
>3.2 us.
>G.  1st output peak, 5.3 us.
>H.  2nd output z.c., 7.8 us.
>I.  2nd output peak, 10.5 us.
>J.  3rd output z.c., 12.9 us (the coil is, of course, continuing to
>ring).
>K.  3rd output peak, 15.5 us.
>L.  4th output z.c., 18.0 us.
>
>>From the above:
>
>1.  Successive output vs. input time delays, z.c to z.c & peak to peak: 
>F-A=3.2, G-B=2.6, H-C=2.2, I-D=2.2, J-E=1.9.
>
>2.  Free-ringing 1/4-cycle times, K-J=2.6 & L-K=2.5...& on & on.
>
>3.  Input 1/4-cycle times, B-A=2.7, C-B=2.9, D-C=2.7, E-D=2.7
>

You'll like this!  I took my MicroSim model and cranked it up to "split the
finest hairs detail" and I got the following prediction.  I also put your
A, B, C,... designations in it.  I kept the input sine wave going just for
reference but I don't think it hurts anything.  I suspect the Microsim
model is very close if not exactly what your are seeing (my time scale is
different).  

http://users.better-dot-org/tfritz/site/misc/Ken03.gif

Sorry about the big complex picture but I didn't want to miss anything...

>So what's it all mean?  It's straining at gnats, is what I think.  Sure,
>there's an itty-bitty extra delay right at the beginning, & then the
>output wave seems to speed up a tad just at the end of the input cycle
>(anticipating the end, do you suppose?--a new phenomenon previously
>unknown to science!).  

The cold hard logical calculations of MicroSim are based totally on good
o'l lumped analysis (unless we tell it not to) and it think it predicted
your results in astounding clarity...

A simple mouse click away is the answer...
http://users.better-dot-org/tfritz/site/misc/Ken04.gif

The FFT of the same waveform is rather choppy since the waveform data is so
limited but I think you'll see what is going on.  When you suddenly "turn
on" the sine wave, your are creating higher order harmonics.  Sort of a
step function.  Those harmonics are adding and subtracting to the stimulus
along with the fundamentl and causing the output to be distorted a bit.
One of those nasty transient analysis things...  

>Of course, I use not-necessarily-finely-calibrated
>equipment but still, one can compare measurement to measurement pretty
>accurately.  I think I find nothing of interest here:  The output wave is
>going to settle down to being 90 degrees behind the input pretty damn
>soon & after that, that's always the same.  I don't see anything that's
>"slow".

What is really interesting, is even at this extreme fine level of detail,
the lumped analysis still seems to hold perfectly true assuming the
computer models and what you see match!  I wonder what a transmission line
secondary theory model would predict?

Great experiment you did here and very observant that you caught this
rather subtle detail!!

>
>Why am I still doing this??  I'm supposed to be retired!  Someone save
>me!

It's this secondary theory stuff...  Richard Hull warns that it can drive
you nuts!  The Corums have been doing it far longer than us.  Hmmmmmm.... ;-))

Cheers,

	Terry


>
>Ken Herrick
>
>On Fri, 14 Apr 2000 22:30:35 -0600 Tesla List <tesla-at-pupman-dot-com> wrote:
>> Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>
>
>>snipped<
>
>> I used a Tek TDS210 digital scope to capture 2500 points and read 
>> them to
>> disk and then to Excel.  I captured the graphs and converted them to 
>> a JPG at:
>> 
>> http://users.better-dot-org/tfritz/site/misc/Ken01.jpg
>> 
>>snipped<
>> 
>> Be very careful of phase information with bare probe ends.  I 
>> recently had
>> a bad experience with that ;-))  I no longer trust the "little wire 
>> on the
>> end of a scope probe" for anything!  The tiny capacitance that is 
>> coupling
>> to the coil's fields to the probe (~0.03pF) is messed with heavily 
>> by the
>> probe's own impedance.
>> 
>> >
>> >And once again, someone tell me what it is that's >"slow"<!
>> 
>> It comes from a paper by the Corums where they talk about their 
>> "slow-wave
>> helical resonator theory".  Basically, they claim that the Tesla 
>> coil
>> secondary is acting like a transmission line with a velocity factor 
>> of
>> ~0.1% (yes, they do claim 1/1000 the speed of light!).  So the wave 
>> is only
>> traveling 1862.8 miles per second.  Thus the wave is "slow".
>> 
>> See their paper (about 10 paragraphs in but mostly the whole first 
>> part) at:
>> 
>> http://www.ttr-dot-com/corum/index.htm
>>
>
>