Re: Two layer primary

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 9/14/00 4:50:04 PM Pacific Daylight Time, tesla-at-pupman-dot-com 
writes:

Mark,

That seems like a good idea.  I was thinking of that too.
Another approach would be to make the top layer flat, and the
bottom layer inclined down and outward (incline the bottom layer
instead of the top layer).  Another way would be to incline them
both to the same degree, the top one would be an inverted cone,
the bottom one a normal cone, so both would have the incline,
but neither would incline that much which may discourage sparks from
striking the primary from the toroid.

John Freau
---

> 
>    My (loony) contribution; could a flat spiral be used for the
>  "bottom" layer and an inverse cone for the "top" layer? Joined at the
>  center, grounded at the outside of the flat coil, tapped at the
>  outside of the cone. Figuring the mutual inductance will be slightly
>  hairy (I'm pretty sure they won't just add algebraically), not to
>  mention the coupling to the secondary but mechanically it sounds good.
>  Better voltage isolation from bottom to top, anyway. Inside diameter
>  will have to be larger than normal because the inside turns are "hot",
>  though.
>  
>  I can't draw ascii, but here goes (sideways view);
>  
>  1     5
>  2    4
>  3   3
>  4  2
>  5-1
>  
>  SSSSSSSSSSS
>  
>  SSSSSSSSSSS
>  
>  5 1
>  4  2
>  3   3
>  2    4
>  1     5
>  |     |
>  G     T
>  
>    Both layers' turns in the same direction, of course.
>  
>    Well, does it look worth the trouble? I've been considering this
>  already, and it's time I put it to the group for criticism.
>  
>    Mark L. Fergerson
>