Re: More Coupling...

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

Original poster: "Barton B. Anderson by way of Terry Fritz <twftesla-at-uswest-dot-net>" <tesla123-at-pacbell-dot-net>

Hi Pete, 

Anytime you can make the measurements would be super! 

Your quandry's are certainly valid. It would be great to know which coupling is
best for a given coil size, input power, etc. (and would add knowledge to
racing spark phenomenon). But I think it will take coupling data (emperical to
the nth degree) to make this happen. As data comes in, patterns emerge. From
patterns, similarities are seen. We begin to identify which coils will obtain
what coupling and from their performance, theory's emerge. Eventually, a high
percentage consensus is reached and our brains have a new wrinkle. Of course,
during this time, some coil mathematical genius (not I) is crunching numbers to
develop (at the least) tables of K, input power, coil size, etc. or eventually
- fast calcs. All this makes for better working coils in the end running at the
highest possible efficiency in the power coupling arena. 

Take care, 
Bart 

BTW - Terry's "best method" of measure K? That's exactly the way to do it! It's
really easy. The hard part is moving the primary up or down each step. I
personally used a caliper to measure standoffs at 1/4 inch increments between
-2 and +2 inches. I wanted to be sure, but there are many other ways to do
this. 

Tesla list wrote: 
>
> Original poster: "Peter Lawrence by way of Terry Fritz <twftesla-at-uswest-dot-net>"
> <Peter.Lawrence-at-Eng.Sun-dot-com> 
>
> Paul, Bart, Terry, etc, 
>                        I'ld like to some day (maybe over xmas vacation) 
> take some K measurements for you guys. I've got helical, and conical-spiral 
> primaries, and am about to make a flat-spiral too. 
>
> What I'ld really like to know though, is how K relates to racing sparks 
> (cross winding sparks on the secondary). I guess it would be important 
> to know what else racing sparks depend on also... 
>
> Like everyone else I've had to at times raise my secondary. It would be 
> nice to know what K would eliminate the inter-winding sparks on my sec, 
> and then I could make my primary have a large enough avg diam to get that 
> low of a K. 
>
> What bothers me at the moment is all I've heard is "smaller K required for 
> the smaller TCs", but no explanation of why -  I'ld like to know why K=0.1 
> is right (or is it?) for my 3.5x11" coil and K=0.3 might be OK for a really 
> larg coil, and if those numbers can be computed from some known dimensions 
> and physical properties. 
>
> -Pete Lawrence.