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TC design programs



Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <Parpp807-at-aol-dot-com>

Hi John and Terry,

I am getting ready to fire up my 48 inch bipolar and if it doesn't turn to 
charcoal I'll
have something to post in a few days.
I just wanna thank Terry and John Freau for all the help and patience with my 
stoopid questions.

I played with the Mark R and the JHC
programs last night. They are certainly very nice; it took me more than an 
hour to do
what seemed to take Terry just minutes. One of these days I am going to go 
back to nature and use the basic physics equations to determine the self and
mutual inductance of a TC. That would be the real learning of the theory. We 
should all try that at least once and then give thanks for the design 
programs.  Am I correct in assuming that these design programs
merely solve the equations, including the empirical ones like Medhurst and 
Wheeler?
As an example: the programs obviously use the wire tables to calculate the DC 
resistance to within 1%. But the true value is easily measured by even an 
inexpensive VOM. I used several meters like a Fluke and a Tek, all of which
agreed within a few percent, or less, of eachother.  Even the Simpson 260 and 
my old Triplett 630 read around 650 Ohms while the program tells me that the 
DC R=277 Ohms which is the wire table value. Same goes for the calculation 
for the coefficient of coupling. Using  Terry's equation for M, the 
experimental values are easy to measure. With the B&K
LCR bridge and the Wavetek 27-XT I can measure Lp and Ls. But these are not 
the 
theoretical values, the 1% values given by the programs. These are the true, 
experimental  values. This is a classic case of circuitous reasoning. There 
is the old story, probably apocryphal, that whenever Einstein  
walked into a physics lab all experiments in progress failed, fuses blew and 
the instrumentation had to be recalibrated.
For $30,000 +/- a few grand I could let HP do the measurements out to umpteen 
decimal places and I wouldn't need the programs or the equations.
That is not to say that we do not need a good text on Tesla coil electrical 
engineering.  Hint  to all.  :-))

I guess as experimentalists the fun comes in assembling a TC and tweaking it
into optimum performance, the heck with the programs and the physics 
equations.
And the heck with $30K for HP. 

Isn't that the way Nikola Tesla would want us to do it?

Happy day,
Ralph Zekelman