RE: How to rise the secondary? (fwd)

---------- Forwarded message ----------
Date: Fri, 17 Jul 1998 05:47:44 +0000
From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: RE: How to rise the secondary? (fwd)

  Terry -

  I like the way you have placed TC computer programs into three categories.
However, the names that you have given these groups do not reflect the true
differences between the programs. I think the groups should be called the
simple TC program, the empirical TC program, and the theoretical TC program.
The empirical program can do what the simple program does and more, however,
the theoretical program cannot do what the empirical program can do. The
theoretical programs like SPICE cannot show spark lengths and other
parameters without the necessary empirical data from real world coils.  

  The JHCTES program started out as a theoretical program to solve the TC
problems. The plan was simple. First order differential equations would
solve for the RCL, etc. parameters.. Second order equations would solve for
the TC pri, sec, and third coil circuits. Fourth order equations would solve
for the classical TC and sixth order equations would solve for the magnifier
with the extra coil. The first and second order equations can easily be set
up on any spreadsheet. The fourth and sixth order equations were another
matter as I found out. The Corum's showed the second and fourth order
equations in their TCTUTOR but did not use them for the examples they showed`.

  I soon realized the theoretical equations would have limited use unless
modified by empirical data to make them conform with real world coils. That
is why I changed the JHCTES program to the empirical type. However, this
program needs to be improved and will be someday. Your research work and the
work of other coilers is very much needed so TC programs can be improved.

  I believe that theoretical programs have a use for Tesla coils and I will
be interested in your program. When are you going to put it on the market?

  John Couture


At 08:39 AM 7/15/98 -0600, you wrote:
>---------- Forwarded message ----------
>Date: Tue, 14 Jul 1998 23:32:00 -0600
>From: terryf-at-verinet-dot-com
>To: Tesla List <tesla-at-pupman-dot-com>
>Subject: RE: How to rise the secondary? (fwd)
>At 03:02 PM 7/14/98 -0600, you wrote:
>>---------- Forwarded message ----------
>>Date: Tue, 14 Jul 1998 19:59:43 +0000
>>From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
>>To: Tesla List <tesla-at-pupman-dot-com>
>>Subject: RE: How to rise the secondary? (fwd)
>>The JHCTES program gives recomended values as defaults for all the input
>>parameters as any program should. However, the defaults can be varied by
>>about +/- 15% and sometimes more and still give a workable coil provided the
>>system is in tune. This is why it is so important that any TC program
>>provide automatic tuning when changes are made. 
>>  Why do I keep pushing the JHCTES program? It is not perfect and someday a
>>coiler will produce a better program. I am hopefully waiting for that day so
>>I can see what I missed (without having to do all that work!). How about it
>>Terry Fritz? And there are others capable of doing all that work.
>>  John Couture
>Hi John,
>        You just had to get me started on this didn't you :-)))
>        I use computer analysis very extensively in my work on Tesla coils.
>Computers are the only way to solve the complex multi-order differential
>equations that govern the operation of our coils.  I feel the models now
>available can reproduce almost all currents and voltage levels with very
>good accuracy.  Often, I have seen something "strange" on a scope and have
>gone back and looked on the model and there it is.  The output sparks are
>still rather mysterious but they are yielding their secrets fast and we
>should soon have fairly good models for at least their average behavior.  
>        I think there are three general categories of Tesla coil design
>programs.  The first, and simplest, are the programs that figure coil
>inductances, resonances, and other very basic information from known
>equations.  The second, are programs like yours that try to predict the not
>so basic but very important parameter based on test data and give a much
>broader view of TC operation.  The third are the standard electrical
>engineering programs that are used for Tesla coil analysis.  All of these
>categories have their advantages and disadvantages.  The simple calculator
>programs give good numbers but lack any big picture information.  The JCHTES
>type programs can give an estimate of much more complex parameters and give
>a better big picture view of TC operation but they sometimes are not able to
>predict subtle parameters or allow for very precise estimations.  The
>full-blown engineering programs can predict behaviors to very good accuracy
>and give great big picture views but are beyond the casual user's price
>range and skill level. 
>        The way I see it, is this.  The complex high level programs can find
>information and trends or do detailed analysis of data that is far too
>esoteric for the casual user.  These programs can also easily be adapted to
>any situation very easily (even tube coils and magnifiers).  The information
>and knowledge the high level programs generate, can be used for the mid
>level programs.  The mid level programs may not be very adaptable but they
>are focused on much more real world needs of coilers and are much easier to
>use.  The basic programs can either do the simple calculations or focus on a
>difficult specific problem (such as coupling coefficients).  All these
>programs have their place and are needed.  The only real requirement is that
>they should all agree with each other and the basic theories or data should
>be sound.  Above all, if a program predicts something, it had better agree
>with the real measured results.
>        Now that we are getting very good at measuring actual TC data we are
>finding that some equations are good and some are having problems. The
>equation Vo=SQRT(Cp/Cs)Vi is turning out to be a real winner.  The equation
>for wire length L=c/(4Fo) is a real looser.  I feel both computer analysis
>and real data are important in inseparable.  The real data keeps the
>computer models on the right track and the computer models can analyze
>situations and data that we could never test just by building and trying.  
>        Much of the recent stuff I have done is based on running many
>computer models and noticing trends that are common to certain situations.
>If I take a sample situation and go measure it in real life the results
>match.  I could never test and find these trends manually.  The computer can
>accelerate the discovery process thousands of times!  Also the models
>themselves are not abstract.  They use actual parameters that one can go and
>measure.  Many models have proven to be simply wrong.  But others have
>worked perfectly.  I often wonder why we didn't see it sooner because it was
>so simple and obvious.  Often it was because it didn't agree with some
>theory that was faulty (like that 1/4 wave stuff :-)).  
>        We truly are at a renaissance of Tesla coil knowledge.  The
>internet, computers, digital scopes and other factors have all come together
>and allowed tremendous leaps in the state of the art.  For so long, a faulty
>theory would persist because no one could disprove it and it was the only
>theory we had.  Now if we have a theory we can probe and analyze it.  We can
>quickly judge its validity.  If it's wrong, we trash it.  If it is right, we
>carve it into our desktop (the wooden kind).  No more spending 50 years
>wondering if it is right, despite the fact it never works :-)  
>        So, do we need another program?  Yes!  We always need another
>program because good ones are so few.  However, they have a much higher
>standard to meet today.  If, for example, the output voltage predicted by a
>program is higher than SQRT(Cp/Cs)Vi it will get attacked viciously.  We
>will calculate, theorize, and measure it into oblivion within days.  If the
>program seems to take primary to secondary clearance lightly :-))) we will
>all question its usefulness.  Malcolm and I discussed the results reported
>by a certain pair of bothers from Ohio earlier this year and had a difficult
>time figuring out they were wrong.  Now it would take minutes to see the
>basic errors.  We are getting very good at this Tesla coil stuff and
>everyone, from the most advanced to the beginner, is getting very
>sophisticated.  Today a number of people, the "newbies", mentioned that they
>didn't understand the first notch.  A few years ago "newbies" wouldn't have
>understood what a capacitor was let along some subtle energy transfer point.
>We still may not understand arcs and gap quenching well enough to predict
>their behavior in advance of building them, but think about it...  What else
>don't we know?
>        I have done much programming and I have wondered if I should make my
>own TC program "offering".  It would take too much time away from other work
>right now so I have put it off.  It is, however, steadily increasing on the
>list of priorities.
>After a long and bazaar day in Terry's life.
>        Terry Fritz