RE: Sparks to Mid-Air (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

---------- Forwarded message ----------
Date: Sat, 27 Oct 2007 08:06:18 +0100
From: Derek <tesla@xxxxxxxxxxxxxxxxxxxxxxxx>
To: 'Tesla list' <tesla@xxxxxxxxxx>
Subject: RE: Sparks to Mid-Air (fwd)

The top load of a tesla coil is one plate of a capacitor, the other plate
would be the floor & walls (if you were inside), or the earth if outside.

What you see as sparks to air (streamers) is the result of the ionisation of
the air by the high voltage created at the topload. 

If you have a large enough voltage you will see streamers from a DC supply I
have a 200KV Cockcroft Walton multiplier that gives 1" visible streamers
from a point (also known as corona) due to leakage into the poorly
conductive air.

The high frequency of a teslacoil driving into the capacitance of the
topload/earth allows more current to be supplied into the corona than at DC
so the effect is more visible and a longer conductive channel can be created
giving much longer streamers for a given voltage.

	Cheers
		Derek 

	http://www.extremeelectronics.co.uk


-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx] 
Sent: 27 October 2007 04:36
To: tesla@xxxxxxxxxx
Subject: Sparks to Mid-Air (fwd)


---------- Forwarded message ----------
Date: Fri, 26 Oct 2007 21:40:18 -0500
From: Crispy <crispy@xxxxxxxxxxx>
To: tesla@xxxxxxxxxx
Subject: Sparks to Mid-Air

Hello,

This is something that's been bugging me for a while.  I like to understand
things that I see and do, but I can't figure out how a Tesla coil can create
sparks into mid-air.  You'd have to have some voltage generated in the air
relative to the Tesla coil topload (I think), but how?  Is this dependent on
the frequency at all?  Like, would a theoretical Tesla coil operating at a
very low frequency still generate sparks into mid-air?

Thanks,
Crispy