Re: Desktop Bipolar Coil

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 6/30/03 1:29:30 AM Eastern Daylight Time, 
tesla-at-pupman-dot-com writes:

John C,

Comments below.....  oh  BTW, it's not a random spark length I'm
considering, it's a maximum spark length.

>John F. -
>
>This is what I mean by nonsense engineering when using random TC spark
>outputs. This possibility also occurs with other engineering systems. Your
>spark 36 inch length can be real, however, the exact watt second input to
>produce this spark cannot be determined and the spark length should not be
>compared to other spark lengths with an assumed same watt second input. Keep
>in mind that the random spark length also has a random watt second input for
>that particular spark. With most engineering systems random outputs can lead
>to over unity energy.
>
>For example -
>
>7500 x .03 = 225 watts
>
>John Freau equation -
>
>   spark inches = 1.7 sqrt(watts)
>          = 1.7 x sqrt(225)
>          = 25.5 inch spark


Correct so far.....


>John Freau 36 inch spark -


Now where did this 36" spark come from?  Did you perchance
take the spark length for a *twin* coil?  Twins give longer sparks
than a regular coil, and I use a different formula for them.  I posted
about this very recently.  In fact I mentioned that a 7.5/30 may give
a 36" spark in a twin coil.  My guess is you must have taken that
figure.  Unfortunately that's mixing apples and oranges.


>   watts = (inches/1.7)^2
>      = (36/1.7)^2
>      = 448 watts


This is correct for a 448 watt input for a regular coil, but for a twin
you only need 225 watts for a 36" spark.  More on that below.


>   unity eff = 448/225
>        = 3.96 = 396% over unity energy


I believe you are confusing the results for a twin coil with results for
a regular coil.  That would indeed give a nonsense result if that's what
you did.  I recently answered a post about a twin coil, and you may
have missed that distinction.


>It is amazing what you can do with numbers using random sparks!
>
>This is the penalty that coilers must pay for using random TC spark lengths.
>Hopefully, in the future TC spark lengths and watt second inputs will be
>better defined.


There is no penalty at all.  But one must be accurate in selecting
the proper formula.  I'll explain it again.

Using a 7.5/30 NST for a normal TC:

   spark length inches = 1.7*sqrt input watts

                        25.5" = 1.7*sqrt 225

Using a 7.5/30 NST for a twin TC:

   spark length inches = 2.4*sqrt input watts
                       36" = 2.4*sqrt input watts

The reason twins give longer sparks for a given input power is
because a twin coil can be considered to be two coils each of
one half the total input power.

I hope this helps to clarify the situation.

John F.



>John Couture
>
>--------------------------------
>
>
>-----Original Message-----
>From: Tesla list [mailto:tesla-at-pupman-dot-com]
>Sent: Saturday, June 28, 2003 9:18 PM
>To: tesla-at-pupman-dot-com
>Subject: Re: Desktop Bipolar Coil
>
>
>Original poster: "by way of Terry Fritz <teslalist-at-qwest-dot-net>"
><FutureT-at-aol-dot-com>
>
>In a message dated 6/28/03 1:00:09 PM Eastern Daylight Time,
>tesla-at-pupman-dot-com writes:
>
> >. It is my understanding the John Freau's equation for
> >spark length is only good for NSTs when the NST is modified.
> >
> >John Couture
>
>
>John,
>
>My equation is good for NST's whether they are modified or not.
>One should use the measured input wattage for the calc, or at
>least the PF corrected VA which should be a reasonably accurate
>approach too.  Consider for example John Morawa's beautiful
>15/30 NST coil which gave 40" sparks from an unmodified NST,
>at 120 volts input.
>
>John
>