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Re: Magnifier system

Great Post Malcolm,
Sorry for butting in but I would like to pose a question. (Or some
observations?)

Below

> 
> > Subject: Re: Magnifier system
> 
> >From bert.hickman-at-aquila-dot-comMon Nov 18 21:16:49 1996
> Date: Mon, 18 Nov 1996 20:31:28 -0800
> From: Bert Hickman <bert.hickman-at-aquila-dot-com>
> To: tesla-at-pupman-dot-com
> Cc: Tesla-list-subscribers-at-poodle.pupman-dot-com
> Subject: Re: Magnifier system
> 
> Malcolm,
> 
> Well thought out post as usual! Comments are inserted below...
> 
> Tesla List wrote:
> >
> > >From MALCOLM-at-directorate.wnp.ac.nzSun Nov 17 22:55:20 1996
> > Date: Mon, 18 Nov 1996 12:54:42 +1200
> > From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
> > To: tesla-at-pupman-dot-com
> > Subject: Re: Magnifier system
> >
> > Hello Jeff,
> >               You ask....
> >
> > > From what I have read, I thought the secondary coil could be
> > > electrically modelled as a series RLC circuit in some sense because
> > > of the way it behaves when driven at different frequencies.
> >
> > Adding a large topload is lumping capacitance at one end so the
> > system does tend to a series RLC. It wouldn't be pure RLC series
> > unless all secondary Cself was eliminated (impossible). Also, since
> > the primary couples mostly into the bottom end of the resonator,
> > waves propagate up and down the structure.
> >
> > > And to
> > > get maximum output voltage at the terminal, we should drive it at
> > > the 1/4 wavelength frequency to produce a voltage maximum at the
> > > terminal, but you pointed out that this is the electrical length of
> > > the wire (not physical) when we wind up the coil. So how exactly is
> > > electrical length mathematically determined?
> >
> > 

<BIG
SNIP>*********************************************************************************************

> Comment:
> Good points! There should be another benefit as well. Most coilers wind
> their resonators using a single uniform wire gauge. This results in a
> tradeoff: ideally the bottom-most (heavy current) portion of the coil
> should be wound with larger diameter wire to minimize skin-effect
> losses, while the lower-current upper portion could benefit from higher
> inductance via more turns of finer gauge wire. By splitting the driver
> and resonator into two optimal pieces, a magnifier provides the best of
> both, while also offering the benefits outlined above.
> 
<BIG
SNIP>********************************************************************************************

> >       Finally, I welcome comments on this analogy. Imagine
> > the resonator as being like a beach. As one moves from bottom to top
> > (deep to shallow), wave tops get higher and higher as the energy
> > moves from the deep to the shallows. Unlike the resonator, the
> > distance from deep to the shallows is considerably greater than a
> > wavelength for a beach so the beach behaves more like a transmissive
> > medium than a resonator (where energy is being bounced between two
> > ends). It might go some way to showing how wave amplitude builds as
> > energy travels from bottom to top though.
> 
> Comments:
> Interesting analogy! About 5 miles from my home we have a "wave pool"
> which consists of a large swimming pool and artifical "beach". The pool
> has large movable plates (hydraulically driven) along one edge of a
> pool. By timing very small movements of the plates to coincide with the
> natural resonant frequency of waves in the pool, large artificial
> breakers can be created at will. These plates would sort of be analogous
> to the high current end of the resonator, and the beach the top end.
> 
> I also envision the resonator as behaving sort of like a fiberglass whip
> antenna. With nothing on the far end, we can move the base back and
> forth slightly at the natural 1/4 wave rate while otherwise holding it
> rigid, thereby building up large oscillations at the far end of the
> whip. By adding a
> substantial weight (capacitance) to the far end of the whip, the
> resonant frequency is now lowered. As we get the top swinging at the
> lower 1/4 wave length, the relative amount of energy focused at the end
> of the whip is much higher for a given amplitude.
> 
> >
> >      Jeff, thanks for asking some very interesting questions.
> >
> > Leaving the field wide open for comment, criticism and experimental
> > evidence,
> > Malcolm
> >
> > PS - I will be measuring spectral characteristics of mag systems
> > before the year is out so hope to answer some of the questions above.
> 
> I look forward to the results!  Thanks again for an interesting and
> informative post!
> 
> Safe coilin' to ya!
> 
> -- Bert --

	I've read and considered the above train with much enjoyment and
consideration, but
there seam to be some things that are being over looked. The words below
are long and windy,
but should get the point accross.

	First, whenever I'm determining the resonate frequency of a secondary I
personally use 
the grid dip method. Attach an "O" scope and RF frequency generator to
the base with dischard 
terminal attached (serial). Simply raise the frequency until the coil
starts to draw max current.

	Second, I'll use the same setup to tune my primary to the secondary by
using a parrell
setup and <SHORTING> my spark. Then keeping my RF generator at the
resonate frequency, I'll adjust
my primary tap until my primary draws minimal current. There by, both
circuits are in tune.

And now the fly lands in the ointment!

	In the obove paragraph I stated that the spark gap was shorted, there
by I was able to obtain
an LC oscillator with a frequency that will cause my secondary to
resonate. But in operation, the
circuit used is a Spark Inductor Capacitor variety. Spark gap circuits,
also known as dampened wave
oscillators, output multple RF frequencies while in operation. From this
understanding come some
questions that need to be asked.

a) How much wave dampening do these secondary frequency impose on the
secondary, as its being excited
   by the primary?

b) Would simply dividing the secondary into two parts reduce the above
effects? 

	The base being few but large AWG(9) turns for capturing as much
magenetic energy as possible and reducing the out of phase effects of
the primary. Top comprising many turns of small AWG(30) 
wire, to take advantage of the voltage rise due to inductance. And of
course the split secondary's
top part would have to be seperated by a distance that reduces the
primary circuits influence. Therefore,
the magnifier could be an attempt to minimize the amount of cross noise
in a tuned resonate circuit.

The above I've written out of pure intuition. Maybe I'm wrong?
Maybe Not.

Please, are these assumptions incorrect?
D. Gowin