RE: TC Spark Energy

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

Original poster: "Malcolm Watts" <m.j.watts-at-massey.ac.nz> 

Hi Gary,
          The point about needing a DC source in order to meter the
firing voltage is well taken. Is there anything to stop one using an
EHT FWBR across the gap and running a 50uA FSD meter through a high
resistance string? Any reason why it won't be at least indicative? I
can't think of one offhand so perhaps someone can. MY EHT supply used
such a meter.

Malcolm

On 10 Mar 2004, at 16:59, Tesla list wrote:

 > Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com>
 >
 > Very true.  But the problem is accurately identifying the gap
 > breakdown voltage.  I'm not sure just stating that "the gaps were set
 > so they just barely fire with just the NST connected"  would be
 > useful.
 >
 > Gary Lau
 > MA, USA
 >
 >
 > Original poster: "Malcolm Watts" <m.j.watts-at-massey.ac.nz>
 >
 > Hi Gary,
 >
 > On 9 Mar 2004, at 20:34, Tesla list wrote:
 >
 >   > Original poster: "Lau, Gary" <gary.lau-at-hp-dot-com>
 >   >
 >   > Since John is asking about Joules, this implies he is talking
 >   about > single-shot operation.  While this may be useful for
 >   quantifying > efficiency in that mode of operation, single-shot
 >   operation is not > something most of us are equipped to do.  A DC
 >   power supply is needed. > > Gary Lau > MA, USA
 >
 > It actually isn't all that hard to get close with a mains-resonant
 > cap/NST combo and a variac slowly turned up until the gap just fires
 > occasionally.
 >
 > Malcolm
 >
 >   >
 >   > Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com>
 >   >
 >   >
 >   >
 >   > Perhaps we can all supply John with some data from each of our
 >   coils > and he could do a tabulation and find an average or
 >   statistical value. > > Dr. Resonance > >   > >   > >   > For over
 >   twenty years the coilers on the List have used output >   spark >
 >   length >   > to compare their coils. The input is usually shown as a
 >   total >   input > watts. >   > The problem is that this does not
 >   give the coiler any indication >   of > the >   > actual energy per
 >   spark to give a true comparison of Tesla coils. >   To > my >   >
 >   knowledge no coiler (see below) has ever determined the TC input >
 >   energy >   > (joules) per spark for these comparisons. Do any
 >   coilers know how > this could >   > be best accomplished? >   > >
 >   > The overall engineering efficiency is represented by >   > >   >
 >     Percent efficiency = 100 x Spark Length/Input Energy (joules) >
 >   > > The spark length could be in centimeters, inches, etc, and the >
 >     input > energy >   > in joules or watt-seconds. The energy in the
 >   spark output is a > complex >   > parameter so would have to be a
 >   compromise. In past postings the > approximate >   > losses in the
 >   TC system have been determined and the >   characteristics > of >
 >   the >   > spark have been estimated. The preliminary tests I have
 >   made gave > 8.5 >   > inches (21.59 cm) per joule of input energy.
 >   Has any other coiler > made these >   > tests? >   > >   > John
 >   Couture >   > >   > -------------------------------- >   > >   > >
 >   > > > >
 >
 >
 >