Re: Please Explain This

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

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


Tesla list wrote:

>Original poster: "EMMETT SECREST" <secrest2032-at-msn-dot-com>
>Being new to TC's there is a lot I have to learn so I could use some 
>insight from you more experienced coilers.  I discovered something that I 
>don't understand and would like to know the reasons for the results. I 
>tuned  for maximum streamer length with a nail on the toroid for breakout. 
>After I had determined what I thought was the best spot I removed the nail 
>and was running the coil and enjoying the results.  I was getting 
>intermittent streamers breaking out from the toroid. Then I decided to see 
>what effect it would have to change the tuning.  I found that by changing 
>the tuning by roughfly 1 turn I got almost constant streamers off the 
>toroid.  Which position is the correct tuning spot? The one with a 
>breakout point or the one without?
>
>Emmett
>
>_
>
>
>
>