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Re: More arc simulations

Hi Richard,

     Models can do wonderful things, They can test new ideas and designs 
quickly, simply, and cheaply.  They can search out and find design problems 
and suggest optimal component values.  My earlier posts had modeling data 
that took about three hours to find.  If I had to make real coils to do 
those tests, it would have taken years.  There is no doubt that models are an 
extremely powerful tool.  However, the problem with models is getting the 
darn things to agree with the real world!
     It is easy to point and click up all kinds of models while sitting in 
the stuffed office chair with a mouse in one hand and a beer in the other 
(my preferred method :-)).  However, unless the modeler drags himself into 
the lab (ok, clear spot in basement :-)) and actually holds the computer
printouts up to the scope photos, the models will never really work.  In
the past, that comparison has been quite depressing!  Hooking a scope
to the output arcs to measure real-time currents is not easy to do.  As
far as I know, Greg and I are the only ones.  Greg's data was collected
early in the year and my probes got good enough to do it last week (my
top terminal is too small to climb into with a scope in hand :-))  
Although, Richard, you may have done this too and haven't mentioned it
in the time I have been on the list.  I know you have most of the tools to
do it ;-)
     In the past, there was not good measuring equipment to feed the models 
with the accurate real world data they need.  A big hot arc burning the 
paint off the ceiling is real nice but the models need to know currents, 
voltages, phase, etc.  Without some way to tie the models to actual results, 
they will stray wildly off course.  However, with good data, they can lock 
right onto a system with remarkable accuracy.  We now have the tools to 
supply very good data to the models and in turn they are producing results 
that are finally agreeing with real results.
     It is very gratifying to know that the results the models now give, 
agree with what the true experts like yourself have noted for years. 
Indeed, the models show that all the parameters have to work together to 
produce a nice output.  They also show that the little tweaks and rules we 
do by experience are in fact very valid once all the complex interactions 
are considered.  Better yet, they suggest new little tweaks we may have 
never suspected.  Indeed, when a model shows something and one can say "Sure 
enough, that's just what Richard has been telling us for years!"  it's 
probably working! :-)
     Unfortunately, the present modeling systems are too complex for the 
"average guy" to use easily.  Hopefully, once we can get these big complex 
things to give realistic results, simpler and easy to use programs can be 
developed.  There is nothing magic about how modeling programs work.  They 
can be striped of all the bells and whistles into much simpler and user 
friendly dedicated tools once the basic mechanics are known.  Fairly soon 
(few years), programs will be able to predict and optimize coil behavior and 
suggest the best parameters to use in their construction given a set of 
"parts at hand" to use.  The models don't have any hurtles to overcome. 
when they get good enough to spit out super coils, we will start building 
them like mad to just what the printout says.  At that point, a little magic 
will be lost forever in coiling, but our sparks will be better so we won't 
notice.  Of course, there will be times when the "seat of the pants" coilers
finds something that our models don't predict and we can sit back and enjoy
us all running around like wild rats trying to figure out what when wrong
with the model.  But that is just the way the modeling world is.
     We have all noticed that old knowledge get rediscovered by others all 
the time.  There is no Tesla coil school so we all start from the very 
beginning without much background.  No teachers or anything to drill the 
basics into us.  We all start fresh at step one and climb our way up.  There 
are many books and such but the authors can't keep up with the state of the 
art (I have started mine six times now, but the table of contents keeps 
changing :-)).  Lots of bleeding edge technology in this hobby but, of 
course, that's why we are all here.
     
     Terry




At 06:59 AM 10/15/98 -0400, you wrote:
snip
>  Malcom,
>
>The TCBOR in tape #1 or 2 back in 1989 and 90 made a number of statements
based
>on our work so it is on record before the internet was ever an item of note.
>
>1. Never build a coil low to the ground.  (losses increase)
>2.  Always use a primary of larger inductance (5-6 turn absolute minimum)
Note*
>doesn't apply to 20 foot diameter primaries.
>3. Always use the smallest tank capacitor and the highest voltage possible
within
>the limits of your power design goals.
>4.  Always use a very high inductance secondary.
>
>
>By 1991 we had added the maximim that........" only the largest toroidal
sizes
>allowed large sparks to be produced and that our recommendation was that the
>toroid should dwarf the resonator."
>
>I think I got on the internet back in 1995 or something like that.  I
screamed
>that then when this list was young.  I have re-iterated all these tips
about 20
>times in numerous posts.
>
> It is nice to see that theory and intellectual reasoning is finally
catching up
>to casual observations by experimenter/researchers of 10 years ago.  Not
that the
>theory or math proves the observations.  Quite the other way around (as
almost
>always) - solutions and working systems forces the theorists to scurry
about in
>search of reasons for seemingly disparate results found in working
systems.  They
>just gotta' fill in those blanks.
>
>Thus far, I haven't seen one of our old maxim's given the lie....Only
supposedly,
>" rediscovered" afresh by each new wave of Tesla buffs lapping up on the
shores
>of real experiment.  While it is true we offered generalizations which
left many
>thirsty for a "model" or something they could simply "plug in values and
turn the
>crank".  I still have not seen that happen to my complete satisfaction.
Lots of
>great efforts and new "mathematical support" for old hard won knowledge,
but no
>"plug in the numbers and spit out a killer system" programs.
>
>I doubt that might ever occur because the math has yet to deal with Arcs
in air
>and plasma dynamics at atmospheric pressures or the divergent
characteristics and
>abilities of individual builders.
>
>What we have is spice or Pspice or this or that model...monte carlo
method,  etc,
>etc, and some "special reasoning" has shown that the old counter-intuitive,
>anti-RF engineering, emperical observations and results are not just a lot of
>hooey.  The secret was that many would be theoreticians never really
gripped the
>idea that spark was all we were after at any price!  Not efficiency, not the
>highest Q, not the highest terminal voltage, etc.  A lot of recent work
posted on
>the net has shown, now theoretically, that large sparks, don't necessarily
mean
>any or all of these optimum RF engineered conditions need be present to the
>ultimate figure inorder get fantastic sparks.
>
>It is and has always been a matter of how to best transform energy into
loss in
>the medium (air) and avoid at all costs..... RF radiation...... our number
one
>enemy.
>
>A good 10KW coil will not be able to be picked up on a decent radio at its
>resonant frequency 1 mile away.
>
>
>Richard Hull, TCBOR
>
>P.S.  The above in no way is meant to demean or nullify the excellent work of
>late by any on this list, but to point out that the theoretical
machinations are
>finally catching up to simple obsevation.  I have remained silent on much
of this
>as I feel with two ears and one  mouth I should listen and learn about
twice as
>much as I spew out or try to teach.  RH
>
>
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