Re: Off-Axis Primary Inductance

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Steve,

While searching the vast 1+ Gig of info on hot-streamer tonight for
something else...  I ran across these pictures that tell much about
Off-Axis Primary Inductance  ;-)

http://hot-streamer-dot-com/temp/TeslaMeet2001-10/Pa210048a.jpg

http://hot-streamer-dot-com/temp/TeslaMeet2001-10/Pa210049a.jpg

Cheers,

	Terry


At 10:40 PM 7/4/2002 -0600, you wrote:
>Hi Coilers,
>
>For my next TC, I am thinking of having a fixed number of turns in a flat
>spiral primary, and some additional off-axis variable inductance in series
>with the primary.  The variable inductance will be used to fine tune the
>primary resonance as the coil is operating.  I am thinking the off-axis
>inductor will be two smaller spirals parallel to each other, with the
>spacing between them variable to change the mutual inductance.
>
>Can any of you help with the following question?
>
>Let's say the primary is of inductance L.  Let's say I start decreasing the
>primary inductance a few percent at a time, and compensate for it by adding
>off-axis inductance to maintain the same L.  About what percentage of the
>total inductance can be off-axis before coil performance noticeably
>degrades?  Anyone have some practical experience with this?
>
>I seem to remember a few years ago someone described an experiment of
>removing one secondary from a large twin coil, so the remaining coil had
>half it's primary inductance off-axis.  I believe he said the performance
>was still very good.
>
>Thanks,
>--Steve Young
>
>