1/4 Wave Theories - What now?

From:  Robert W. Stephens [SMTP:rwstephens-at-headwaters-dot-com]
Sent:  Wednesday, June 03, 1998 10:56 PM
To:  Tesla List
Subject:  Re: 1/4 Wave Theories - What now?

> To:            "'Tesla List'" <tesla-at-pupman-dot-com>
> Subject:       1/4 Wave Theories - What now?
> Date:          Wed, 3 Jun 1998 20:23:14 -0500
> From:          Tesla List <tesla-at-pupman-dot-com>

> ----------
> From:  Malcolm Watts [SMTP:MALCOLM-at-directorate.wnp.ac.nz]
> Sent:  Tuesday, June 02, 1998 4:53 PM
> To:  Tesla List
> Subject:  Re: 1/4 Wave Theories - What now?
> Hi All,
> > From:  D.C. Cox [SMTP:DR.RESONANCE-at-next-wave-dot-net]
> > Sent:  Monday, June 01, 1998 12:30 PM
> > To:  Tesla List
> > Subject:  Re: 1/4 Wave Theories - What now?
> > 
> > to: Terry
> > 
> > I think most of the capacitance is turn to turn but it would be very easy
> > to test your theory.  Measure the cap of a secondary inductor and then
> > elevate it approx 25-30 feet above ground (in a sense isolate it from any
> > nearby ground plane) and then measure the capacitance again.  If the cap is
> > turn to ground the value should diminish considerably --- if the cap is
> > turn to turn as I suspect the value should not change very much.  You could
> > elevate it on some plastic spools, a wooden pole, or even a bunch of
> > cardboard boxes stack up high.  A simple test that will validate your
> > theory or invalidate it.
> > 
> > DR.RESONANCE-at-next-wave-dot-net
> I have actually done this with a number of coils and Cself does 
> diminish. I think there is a point where one runs into a law of 
> diminishing returns though. Typically, one still has a lead running 
> up to the base of the coil in order to drive it for measurement 
> purposes and this itself adds capacitance to the system. This is 
> precisely the problem Tesla ran into when trying to measure the 
> capacitance of elevated "isolated" spheres. They were never truly 
> isolated and Richard Hull made some interesting observations about 
> this in the Guide to the Notes. Perhaps he could say more about this.
> Also, the further the coil is elevated, the smaller is the fractional
> distance moved from ground.
> Malcolm


Instead of a bare conductor run from your test equipment to the 
resonator which you are raising above ground plane, use a long piece 
of flexible coaxial cable like RG-8.  Coiled up on the ground or 
extended vertically in the air, the center conductor will provide a 
constant capacitance to earth.  You can easily subtract this constant 
term from your experiment to isolate the coil self-C.

Have fun.

Robert W. Stephens
Lindsay Scientific Co.
RR1 Shelburne, ON Canada L0N-1S5
Tel: 1-519-925-1771   Fax: 
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