Re: Why the primary is a flat spiral?

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

Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>" <davep-at-quik-dot-com>



Tesla list wrote:

> Original poster: "Shaun Epp by way of Terry Fritz <twftesla-at-qwest-dot-net>"

><scepp-at-mts-dot-net>
 
> I did a demonstration to a group of Ham Radio people I know

>this evening and it went really well.  I demonstrated the

>spark show, burning / stripping a CD, tube light lit from a

>distance and on top of the coil.  They where all impressed,

>I even recieved  a round of applause  : ^ ).  One woman asked
> me why the primary coil was flat and I was somewhat stumped.


 	Any primary shape will couple energy to the secondary.

	Flat ones are (among other things):
		Mechanically more stable
		Further from the 'hot' end of the secondary
	Tesla used both, apparently.  His largest (Colorado
	Springs) coils apparently had a single turn Primary,
	hence it was 'flat'.

	Arguably a 'stand up' primary has tighter magnetic
	coupling, which may improve energy efficiency.  In
	moist complex systems, there are tradeoffs, rather than
	'single right answers'.


> What other stage tricks do others do?


	Ion motors?
	Lighting lamps remotely with various 'antennas' (or
	capacity plates.)
	It occurs to me Tesla had a demo of having two loops
	of wire, in the same plane, of different diameters
	(say 3" and 6"?  Guessing.  Experiment...), which
	would do a ring of fire (sparks)?  (I've not seen this
	done, dunno how hard it is to get to work...)

	best
	dwp