RE: 'true" spark length was Re: Desktop Bipolar Coil

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

Original poster: "John H. Couture by way of Terry Fritz <teslalist-at-qwest-dot-net>" <couturejh-at-mgte-dot-com>


Matt -

I agree that there is a big problem in using a spark length for comparing
the output of Tesla coils. I have made suggestions in the past to the List
regarding other methods on how this can be done. However, if spark length is
to be used the true watt second (energy) input for that particular spark
must be determined. At present coilers are not able to find this elusive
input.

As for pining down the spark length I believe the controlled spark is the
best approach.

John Couture

---------------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Monday, June 30, 2003 7:11 PM
To: tesla-at-pupman-dot-com
Subject: 'true" spark length was Re: Desktop Bipolar Coil


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

In a message dated 6/30/03 1:41:08 PM Eastern Daylight Time,
tesla-at-pupman-dot-com writes:


 >John is quite correct on this matter.
 >
 >If you want to determine a "true" spark length for you coil, rectify the AC
 >to DC and then insert a large value resistor (say 20 Meg) in series with
the
 >HV power supply to the cap.  This will "fire" the circuit once every 2-3
 >seconds.
 >
 >You measure this output spark length and you will have a close to true
value
 >for the output of your system.  This prevents "spark growth" as a function
 >of power input.
 >
 >This is a HF AC current however the spark length is very close to what a DC
 >peak value would be and is accurate to determine actual output voltage.
 >This also is in very close agreement with Terry Fritz's antenna pickup
 >voltages.
 >
 >Dr. Resonance


Hi Dr. R, John, All,

         I am not at all sure that the "true" spark length is even a
definable concept. It's like asking what is the "true" maximum height a
given athlete can jump, or the "true" maximum speed a particular driver in
a given car can achieve. It all depends on the day, location, environmental
conditions and the breakfast menu.

         Since electrical discharge is a fractal phenomenon, the "True"
length is indeterminate and may be anything greater than the straight line
distance and less than infinity. One can talk about the greatest
straight-line interval achieved with a given coil under such-and-such
conditions, etc. One can determine through many multiple tests a "most
probable" upper bound on spark interval (not length). TCs are far too
complex to be able to speak intelligently about single-value performance.

Hopefully this may help take some of the fuzziness out of the discussion.

Matt D.