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Re: All pain no gain



Original poster: "Barton B. Anderson by way of Terry Fritz <twftesla-at-uswest-dot-net>" <tesla123-at-pacbell-dot-net>

Hi Nate,

Thanks for the comments and comparisons of the two programs. I know John
and I both appreciate
responses -  both pros and cons.

As I was reading this, I couldn't help but understand a problem measuring a
cap if you don't have
the equipment. If you don't have the equipment, don't worry about it. Both
programs should get you
close because I doubt the capacitance variation will be that great.
Obvisouly, the more caps used
adds to the amount of tolerance variations from a calc'd value, but it's
probably still pretty
close within a turn or two.

Regarding the toroid calc, I would go with John's value. My calc is a basic
toroid capacitance, but
the fact is the ground plane, walls, secondary, primary, etc.  all affect
the final capacitance to
the system. I think John is using a better approach based on empirical data
in this area. Part of
the reason for the suggestion to use E-Tesla 6 is that this is probably the
best method for the
toroids affect to the entire system as it does take into account the
surroundings. Sorry to hear
about your Excel errors. What's the error? We can probably help. A lot of
us are unfortunately
aqainted with Excel and Windows anticks.

Take care,
Bart A.

Tesla list wrote:

> Original poster: "Nathan Morris by way of Terry Fritz
<twftesla-at-uswest-dot-net>" <themfam-at-home-dot-com>
>
> Mr. Couture
>
> I ran my numbers using the JHCTES program 3.2 and I came up with a primary
> tap of 11.83.  I have been trying to rerun my numbers using  JavaTC 7.04 but
> the tuning feature is not working at this moment.  I would like to clarify
> right now that the gross miscalculation of my primary tap was a result of my
> haste and NOT JavaTC 7.04.  As soon as I am able to use the tuning feature
> again I will double check my numbers and find out where I went wrong.  I do
> have to admit, having used both programs I find JavaTC 7.04 to be more
> flexible.  While running 3.2 I had to go back to 7.04 for a quick re calc on
> my secondary in order to complete the number of turns and turns per inch
> fields required on 3.2.  I also had to enter a S.W.A.G in the torroid
> capacitance field.  Unfortunately I do not have the necessary tools needed
> to measure capacitance readily available.  This leaves me reading the
> nomenclature on the pri caps and guestimating on my torroid capacitance, or
> if I am using 7.04 I can input the data in the torroid dimension fields and
> let it guestimate for me.    JHCTES 3.2 is fast and to the point.  I have
> added it to my favorites for this reason.  This is just my take on a
> comparrison of the two programs.  I have also checked out Ed's spredsheet
> and have tried to open E-Tesla6 with Excell.  Now every time I go there and
> try to open it, Excell pops up on my screen with an error message.
>
> --Nate
>
> ----- Original Message -----
> From: Tesla list <tesla-at-pupman-dot-com>
> To: <tesla-at-pupman-dot-com>
> Sent: Saturday, March 10, 2001 1:38 PM
> Subject: RE: All pain no gain
>
> > Original poster: "John H. Couture by way of Terry Fritz
> <twftesla-at-uswest-dot-net>" <couturejh-at-worldnet.att-dot-net>
> >
> >
> > Bart -
> >
> > I ran the numbers for Nathan's coil in your Java program and came up with
> > the same outputs as the JHCTES program. It helped that I knew the answers
> > from the JHCTES program because your program is more complex. It is
> obvious
> > that the two programs are using the same calcs. One slight exception is in
>
> > the coil self capacitance calc. You are using a different Medhurst
> equation.
> > I adjusted the secondary terminal pf to allow for this slight difference.
> >
> > One of the calcs thatI believe should be changed in your program is the
> one
> > for the sec wire insulation thickness. For Nathan's coil I enterred 1 mil
> > with zero for the spacing. This gave me the incorrect TPI and sec turns.
> > This was corrected when I entered an incorrect 2 mils. This also has a
> large
> > effect on the sec inductance.
> >
> > You are having the problem I had with the JHCTES program over the more
> than
> > 10 years of its existance. That is that coilers do not enter the correct
> > inputs that truly represent their coils. When they test their coils and
> find
> > something different they say the calcs don't work. The pri and the sec
> > capacitances are the biggest culprits. The capacitances of these two
> > parameters have a profound effect in tuning the TC system. This is why I
> > recommended that Nathan actually measure the pri capacitance.
> >
> > The secondary capacitance is another matter. This is where Terry's
> E-Tesla6
> > program would be of help. However, this program like all programs suffers
> > from the fact that every time you add an input you increase the chance of
> > the user entering the wrong value. This is why the JHCTES Ver 3.2 program
> > uses only 8 inputs to determine if the system is in tune. This is the
> > absolute minimum required to find the critical tuning condition.
> >
> > There is still a lot more to TC design. I hope that Nathan will not accept
> > the 15.52 pri turns I mentioned without verifying the actual sec TPI, pri
> > dimensions, etc, and entering these actual values in the TC programs. I
> was
> > not able to determine where Nathan strayed with the Java program to come
> up
> > with 25 pri turns.
> >
> > John Couture
> >
> > ------------------------
> >
> > -----Original Message-----
> > From: Tesla list [mailto:tesla-at-pupman-dot-com]
> > Sent: Thursday, March 08, 2001 9:44 PM
> > To: tesla-at-pupman-dot-com
> > Subject: Re: All pain no gain
> >
> >
> > Original poster: "Barton B. Anderson by way of Terry Fritz
> > <twftesla-at-uswest-dot-net>" <tesla123-at-pacbell-dot-net>
> >
> > Hi Nate,
> >
> > I'm curious. Do you have a bit more dimensional info on your primary?
> > JavaTC, JHCTES, Ed Sonderman's
> > Spreadsheet, WinTesla, etc.. are all very close to one another. For the
> > most part, we all use the same calc's,
> > however, there are a few calcs we go about differently for different
> > reasons. I suspect there are dimensions
> > which are off one way or another due to the degree the tap point you
> > indicated is off. JavaTC shows about 18
> > turns if I use similar inputs to Johns. But, everyone is kind of guessing
> > at a few unknown dimensions. If the
> > program is that far off I'd like to find out why. Others have used it with
> > excellent results at first light.
> > Yours is the first case I've heard otherwise which is partially why I'm
> > interested in your input dimensions vs.
> > your actual measurements.
> >
> > For TPI, simply count the turns in an inch and verify this at different
> > points (this isn't exact, but it's as
> > close as you'll get without counting the entire coil - as I once did).
> This
> > helps fine tune the secondary which
> > of course affects the resonant frequency and thus primary calcs. I would
> > also back up John about measuring the
> > cap and verifying all dimensions. They do make a difference regardless of
> > which program you use. I personally
> > like to use them all.
> >
> > Keep us posted.
> >
> > Take care,
> > Bart A.
> >
> > Tesla list wrote:
> >
> > > Original poster: "John H. Couture by way of Terry Fritz
> > <twftesla-at-uswest-dot-net>" <couturejh-at-worldnet.att-dot-net>
> > >
> > > Nathan -
> > >
> > > The JHCTES program indicates that your TC system is out of tune.
> > > Go to my web site at
> > >       http://home.att-dot-net/~couturejh
> > > go to the on line JHCTES Ver 3.2 program
> > > and enter Secondary parameters
> > >
> > > Rad      2.25
> > > Turns    1577
> > > TPI        83   1577/83 = 19 " lg
> > > Sec term   18
> > >
> > > Pri cap    .01
> > > Avg rad   9.00
> > > Width     5.00
> > > Gives    15.58 pri turns
> > >
> > > Measure the actual pri cap value (.01?) and enter.
> > > Verify the other pri and secondary parameter values and enter.
> > > Your coil will then be in tune.
> > > All you will then need is to make sure the NST is working properly. You
> > > should get a 16 inch streamer spark or a 9 inch controlled spark. A
> larger
> > > NST can be used with this coil.
> > >
> > > John Couture
> > >
> > > ----------------------------------
> > >
> > > -----Original Message-----
> > > From: Tesla list [mailto:tesla-at-pupman-dot-com]
> > > Sent: Thursday, March 08, 2001 6:55 AM
> > > To: tesla-at-pupman-dot-com
> > > Subject: Re: All pain no gain
> > >
> > > Original poster: "Nathan Morris by way of Terry Fritz
> > <twftesla-at-uswest-dot-net>"
> > > <themfam-at-home-dot-com>
> > >
> > > All,
> > > Thanks for all of the suggestions.  Here are the specs on my coil and
> more
> > > information on my attempted first light setup.
> > >
> > > I used the JavaScript Tesla Coil Designer
> > > For Classic Dual-Tuned Resonant Transformers
> > > JavaTC 7.04
> > > Copyright © 2000 by Barton B. Anderson
> > >
> > > My primary is 23 turns of insulated #10 AWG stranded.
> > > My secondary is #30 mag wire on a 19 x 4.5 PVC form.
> > > My torroid has an ID of 8 inches an OD of 16 inches and a chord of 4
> > inches.
> > > For the first light attempt I was running small a 7.5 kv 20 ma NST (no
> > > variac)
> > > My cap is two rows of four .02 uf 3kv caps.  The two rows of four are
> > > parralled for a total tank capacitance of .01 uf.
> > > My gap has 4 gaps that are quenched by a 120 VAC microwave blower.  Each
> > gap
> > > is individually adjustable.  Before energizing my primary I set the gap
> so
> > > that all 4 were sharing the duty.
> > > JavaScript Tesla Coil Designer suggests a primary tap at turn 25.  I got
> > > shorted on my wire from the hardware store so I was using the length of
> my
> > > primary.  I thought it might be close enough to get me started but to be
> > > quite honest I believe it is the main issue with my current setup.
> > > Oh yea, almost forgot, I was using the wall outlet for grounding my
> > > secondary.  While mowing the yard however, I did find 2 inches of a
> copper
> > > ground rod sticking up near my service entrance/breaker pannel.
> > >
> > > ----- Original Message -----
> > > From: Tesla list <tesla-at-pupman-dot-com>
> > > To: <tesla-at-pupman-dot-com>
> > > Sent: Wednesday, March 07, 2001 8:27 AM
> > > Subject: Re: All pain no gain
> > >
> > > > Original poster: "Bert Hickman by way of Terry Fritz
> > > <twftesla-at-uswest-dot-net>" <bert.hickman-at-aquila-dot-net>
> > > >
> > > > Nate,
> > > >
> > > > Did you use any design tools (WinTesla, JHCTES, etc.) to aid you in
> the
> > > > calculations/design of your coil? If you have a small coil (~500 VA or
> > > > less), you can get by with using the power line ground (although its
> > > > really not recommended). There are many reasons why you may not be
> > > > seeing breakout, but in order to figure out what to do more
> information
> > > > is needed about your system. Please provide the information below and
> we
> > > > should be able to suggest some fixes. The fact that your gap is firing
> > > > loudly is a good sign - it appears that your HV source and tank cap
> are
> > > > operational.
> > > >
> > > > Some possible reasons for failure to break out can include:
> > > > 1. Tank cap is too small (energy/bang too small)
> > > > 2. Toroid radius of curvature too large
> > > > 3. Coil is severely mistuned
> > > > 4. Secondary is internally shorting
> > > > 5. Coupling coefficient is too low
> > > > 6. Primary circuit miswired
> > > >
> > > >------------------  snip
> >
> >
> >
> >