Re: Please Explain This

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

Original poster: "Malcolm Watts" <m.j.watts-at-massey.ac.nz> 

HI Bart, all,

On 19 Dec 2003, at 7:44, Tesla list wrote:

 > Original poster: Bart Anderson <classi6-at-classictesla-dot-com>
 >
 > Hi Emmett,
 >
 > Some coilers (myself included) run coils detuned in the range of 3% to
 > 8%, where the primary resonant frequency is slightly lower than the
 > secondary resonant frequency (detuned high on inductance). When you
 > changed your tuning, did you "add" an "extra" turn? This would be
 > detuning the coil high on inductance.
 >
 > The idea here is to offset spark loading (additional C) by adding a
 > little L. Also related, by tuning the primary low inductance (less
 > turns), spark loading may bring the system further out of tune and
 > stress the secondary causing similar results to having the toroid too
 > high (voltage stress). At least I've seen this on my coils.
 >
 > It should also be noted that the affects of spark loading may or may
 > not be noticed. I think much depends on how spark loading affects the
 > distributed capacitance of the secondary.
 >
 > Take care,
 > Bart

There may be more to offset tuning than changing primary tune to
match simple capacitive loading of the output with streamer
formation. In fact, there is an equivalence between changing this
tuning and changing k (to keep energy transfer up with a change in
loading from light to heavy). Just thought I'd mention it.

Malcolm