RE: Reducing toroid size

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

Original poster: "Alan Yang by way of Terry Fritz <twftesla-at-qwest-dot-net>" <megavolt121-at-attbi-dot-com>

Jolyon-
	The torroid is essentially a capacitor. Think of hte torroid as one plate
of the capacitor and the floor as the other plate. The air in between is the
dialectric. I heard this from a professor -at- UC Santa Cruz. This is the
easiest explanation to why the torroid is a capacitor that I can think of.

-Alan

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Sunday, June 09, 2002 4:17 PM
To: tesla-at-pupman-dot-com
Subject: Re: Reducing toroid size


Original poster: "Jolyon Vater Cox by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <jolyon-at-vatercox.freeserve.co.uk>

Isn't the toroid essentially a capacitor, necessary to tune the secondary to
the primary frequency as well as to store energy, and as such isn't the
toroid capacitance critical to the primary/secondary frequency "match"?

The reason for the 2 foot toroid is that it gives biggest sparks - I have
tried 4 6/8" and 5 7/8" toriods and even a 9" pie tin
and all I have got are weak 1"-2" sparks to a sharply pointed object that
was NOT grounded-
the strange thing was that sparks drawn to a grounded object were shorter;
was low-Q the likely culpit here?

With 3 saltwater caps coil tunes at 4 3/4 primary turns -was 6 3/4 turns
with only 2 saltwater caps
this is to be expected as with MORE primary capacitance the primary will
"match" the secondary with less primary inductance ie fewer primary turns-
providing the secondary parameters remain the same, but If the toroid size
were increased wouldn't the primary tap move back upwards- as secondary
frequency would be lower and more primary inductance would be needed to
match this?

So if I add more capacitance to my primary won't I have to move the primary
tap down unless I increase toroid diameter proportionately- that is, unless
I add more secondary turns?

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, June 09, 2002 4:03 AM
Subject: Re: Reducing toroid size


> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<FutureT-at-aol-dot-com>
>
> In a message dated 6/8/02 8:19:11 PM Eastern Daylight Time,
tesla-at-pupman-dot-com
> writes:
>
> You're not really getting any benefit from the bicycle wheel.
> You can simply replace it with a smaller toroid and get the same
> or better results.  You could put a sphere about 4" dia on top
> of the secondary and get a good result.  or a toroid that is about
> 2" x 6" or 2" x 8" something like that.  You can just retune
> the primary (change the tap point) to keep the coil in tune.
> You may need to install a breakout point or bump on the
> toroid to permit breakout, depending on its radius of curvature.
>
> If you make the new secondary with thin wire, it won't tune
> at the same primary tap point even with a small toroid.  I'd just
> leave the secondary as-is for now, and just install a smaller
> toroid.
>
> John
>
>
>
> >
> > I am getting 3"-4" from my 3"dia x 10 7/8"high 440 turn secondary but
then, I
> > am using a massive 2 foot bicycle wheel as a toroid; I feel that
> >
> > the setup takes up too much space for such a modest performance and it
would
> > be
> > desireable to reduce the physical size of the TC to some extent.
> >
> > Would it be possible to get same performance (or better) with a much
smaller
> > toroid if the secondary had same area but was wound with finer wire eg.
880
> > turns of 0.011" diameter wire instead of the 440 turns of 0.022"
diameter
> > wire
> > that I am presently using?
> >
> > I have calculated that this will quadruple the secondary inductance so I
will
> > have to quarter the toroid capacitance to keep the secondary in tune -so
will
> > I
> > have to quarter the physical size of the toroid to accomplish this?
> >
> >
>
>
>
>
>
>