Re: Tank Capacitance: what is the limit (Gap)

Subject:       Re: Tank Capacitance: what is the limit
       Date:   Mon, 28 Apr 1997 13:12:24 +1200
       From:   "Malcolm Watts" <MALCOLM-at-directorate.wnp.ac.nz>
Organization:  Wellington Polytechnic, NZ
         To:   tesla-at-pupman-dot-com

Hi Greg and all,

>       From:   Greg Leyh <lod-at-pacbell-dot-net>
>         To:   Tesla List <tesla-at-pupman-dot-com>

> 2) The min req'd Q factor for the primary ckt -- the unloaded Q of 
> the pri ckt should 10 or greater, otherwise the rotary gap starts
> to dissapate too much power.  The Q of the pri is approximately
> SQRT(L/Cpri) divided by Rgap.  Since Rgap is more or less fixed,
> it can be seen that an arbitrarily large pri cap will result in
> in a low Q, with most of the input power being dissapated in the gap.

If Rgap is "more or less fixed", why does one get a linear decrement
on the scope if all other components have a low ESR? The kind of 
picture I got was of Rgap varying sinusoidally with primary current.