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Re: Real data from real experiments.
Tesla List wrote:
>
> > > Subject: Re: Real data from real experiments.
> > Subject: Re: Real data from real experiments.
> > > Subject: Re: Real data from real experiments.
>
> >From ccurran-at-execpc-dot-comTue Nov 12 21:46:57 1996
> Date: Tue, 12 Nov 1996 03:35:46 -0600
> From: Chuck Curran <ccurran-at-execpc-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: Real data from real experiments.
>
> Tesla List wrote:
> >
> > > Subject: Re: Real data from real experiments.
> >
> > >From hullr-at-whitlock-dot-comMon Nov 11 23:00:36 1996
> > Date: Mon, 11 Nov 1996 16:11:05 -0800
> > From: Richard Hull <hullr-at-whitlock-dot-com>
> > To: tesla-at-pupman-dot-com
> > Subject: Re: Real data from real experiments.
> >
> > Tesla List wrote:
> > >
> > > >From MALCOLM-at-directorate.wnp.ac.nzSun Nov 10 21:43:05 1996
> > > Date: Mon, 11 Nov 1996 10:51:14 +1200
> > > From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
> > > To: tesla-at-pupman-dot-com
> > > Subject: Re: Real data from real experiments.
> > >
> > > Brent,
> > > There is an even better reason to use high Vcap, low-C in a
> > > primary....
> > >
> > > <masssive snip>
> > > > No charge is actually 'lost' - rather, it is simply re-distributed.
> > > > The total stored potential energy is reduced though, according to the
> > > > square of the voltage. Seems to me that this is exactly the reason why
> > > > we use small value capacitors with a heaping amount of very high voltage
> > > > in the primary circuit!
> > >
> > > Example : let bang size = E, cap = C, primary = L. Surge impedance =
> > > SQRT(L/C), peak current inversely proportional to surge impedance
> > > and gap loss proportional to Ipk.
> > >
> > > Let's double our surge impedance by halving C and doubling L (same
> > > frequency) and keep bang size up by increasing voltage to compensate
> > > for a drop in C.
> > > We now have Z surge = 2x original, V = SQRT2 x original voltage (keep
> > > E constant) giving current decreased by SQRT2, gap losses therefore
> > > reduced by SQRT2.
> > > Okay, this all needs the appropriate calculus done to truly
> > > quantify peak values etc. but I think you can see the benefit
> > > attainable.
> > >
> > > Think I got that all right but stand to be corrected as usual,
> > > Malcolm
> >
> > Malcolm,
> >
> > I have long known and harped that the high L low C coil outperformed
> > other systems with the reverse set of parameters, but your explaination
> > is quite good and insightful.
> >
> > Richard Hull, TCBOR
>
> Richard/Malcom:
> I hope I am not repeating a question already asked,but here goes. Is
> there a way you could suggest to select the best size cap for a given
> set of coil parameters?
> I have that new PVC form I mentioned and I am ready to start the primary
> component selection and construction. The primary is a piece of 15 1/4"
> O.D. PVC and the coil will be 50" of #15 wire, or 831 turns. Primary was
> going to be 5/8" thin wall copper tube. I was considering a .1 mfd cap,
> but I really do not have a feel for what exactly the primary L/C ratio
> should be for optimum spark. Your comments woud be appreciated. Thanks
>
> Chuck Curran
Chuck,
I would say that it depends on the final resonant frequency. For a .1uf
I would want a 100+ uh primary winding. If the Freq allows this then OK.
Richard Hull, TCBOR