Re: toroid question

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

Hi Allan,

On 27 Jan 2002, at 23:30, Tesla list wrote:

> Original poster: "Allanh by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<allanh-at-starband-dot-net>
> 
> It has occured to me that using a toroid with no conducting material in the
> center in effect places a
> shorted turn in the magnetic field and would cause
> very high current to flow. Upon testing my theory on
> my coil, I found very little difference in the two types.
> I would like to know why the shorted turn toroid doesn't
> consume great quantities of power.
> 
> any ideas?

Why should having no conducting material in the centre be worse? You 
could view either form of construction as being a shorted turn, 
possibly worse in the case of a central conductor since it is closer 
to the windings. In fact, the requirement for anything to consume 
power is that it must be somewhat resistive. Most terminals are close 
to perfectly conducting. There can't be much doubt that the 
arrangement modifies the operating properties of the resonator to 
some degree, but then connecting something to the top of the windings 
does that anyway. Since cutting a slit in the toroid so that a 
shorted turn no longer exists has little effect on Fr (it tends to go 
up a bit if you do this), it must be telling you something about the 
way the resonator operates (how currents are distributed for example) 
and how the two interact. I'm not sure if this has been covered in 
the tssp project yet. Perhaps Paul Nicholson might care to comment?

Regards,
Malcolm
<snip>