[FwdX: [TCML] High Primary Q]

[bartb]

Hi Dave,

The issue is that it has been stated high Q and I was working with 
someone else off line regarding a flat ribbon primary (which is why I 
showed that particular calculation). In the process of looking, it 
didn't look high at all and so I thought I'd throw it at the list.

I'm going to send you a paper which I think you'll find interesting 
regarding spark gap resistance. It's by Harrison, Ferguson, and Monjo 
from Maxwell Laboratories: "Determining The Losses In Spark Gap Switches".

I'll send as a pdf.

Take care,
Bart

David N. Van Doren wrote:
> Hi Bart
> I don't see what the issue is.
> Q has always been Reactance divided by Resistance.
> The trick it to determine the real resistance.
> Copper losses are just one source of losses.
> One can calculate the skin depth of a tube and
> use the resulting thin walled tube as the conductor.
> But according to Dr Gary L. Johnson's Tesla Coil Paper,
> Table 1, Proximity effects, skin depth R can be multiplied
> by a factor of a little over 1 to as much as 5, depending
> on the coil design.
> But for me the biggest uncertainty of primary circuit losses
> is in the spark gap. The conditions the determine the gap
> Resistance can and do vary wildly. The gap resistance of
> a coil running kiloAmps is most like very different
> from a coil running a couple hundred amps.
> This is what prompted me to ask the list what
> it knew about Spark Gap Resistance.
> Gap resistance is very tough for me to measure and
> until I have some definitive data I can only assume that
> It could range as high as the R's of the copper.
> Than I would like to prove to my self the effects of
> Dielectric losses in the capacitor. I don't know
> how to equate loss factor to equivalent resistive losses.
> Maybe someone here can show me?
> Then there are radiative losses and I don't know
> any thing about this.
> So in the end Q may in fact maybe quite abit lower.
> Maybe this is why Tesla turned to the Magnifier,
> to in crease the coefficient of coupling to reduce
> the number of loss cycles the energy had to endure.
>
> Dave