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Re: All pain no gain



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
>
>
>
>