Re: A primary question

Subject:       Re: A primary question
       Date:   Tue, 22 Apr 1997 08:12:28 +1200
       From:   "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz>
Organization:  Wellington Polytechnic, NZ
         To:   tesla-at-pupman-dot-com

HI Skip, all,

> I would like to pose a question for the list. Disregarding
> primary/secondary arc-over problems...what if one were to design and
> build three different primaries as follows:
> 1. a solenoidal wound coil of the approximate diameter of the secondary
> designed to a specific L. I think this coil could actually be a larger
> diameter without changing the premise.
> 2. a pancake wound coil of the same L with spacing to allow the
> secondary to fit in if necessary for k adjustment.
> 3. An inverted pancake coil of the same L designed using accepted
> techniques
> Now, the question.....Using the same secondary and adjusting the
> coupling to be equal for each of the three different primaries, will the
> TC function any differently in each configuration?
> I will appreciate any and all comments and discussion. I believe the
> design of the primary is the single most important part of a TC and I
> believe it has largely been ignored.
> Skip

In my opinion, an inductor is an inductor. However, some shapes are 
going to couple to different degrees to different parts of the 
secondary. I've noticed no great operational benefit from any 
particular design. My single guiding rule for a good primary is to get
Zsurge as high as poss.