Re: Voltage determination

[Rscopper-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

I just rebuilt my gaps to handle the new pig, and fired it up Saturday
evening.  Going from approx 4KW to 8.5KW only gave me about 1 foot in extra
spark length.

Some interesting observations:  

1) Before, when the arc hit a ground target, all other spark from the top
would stop, Now, there are still streamers coming from other sides of the
toroid even when one is hitting a target.

2)There is corona coming from everywhere!  between my stacked secondaries,
and around the output arc itself.  Maybe I've reached the maximum power my
secondaries can handle, and any extra power is wasted in corona.  I'm going
to build a new larger toroid this week to see if it helps.

In the end I had 2 stacked 8-inch secondaries wound with 23 AWG with a
total inductance of 125mh, and the whole thing was about 9 feet tall
including toroid.

R. Scott Coppersmith




In a message dated Mon, 24 Jul 2000  2:14:13 AM Eastern Daylight Time,
"Tesla list" <tesla-at-pupman-dot-com> writes:

<< Original poster: Tesla729-at-cs-dot-com 

In a message dated 7/23/00 8:44:19 PM Central Daylight Time, tesla-at-pupman-dot-com 
writes:

<<  It may be impossible to point to one element alone (e.g. 
 voltage) and say that it is resonsible for a certain length of 
 spark since it won't get very far if there is no substantial 
 source of charge to back it up.
  >>

You know, I've read a text somewhere in regard to this subject
that said something to the affect that a pulsed discharge from
an induction coil may require ~300 kv for a mere 6" spark, but
a 140 kvDC power supply may require 24" of seperation between
the output leads or terminals to prevent a possible flashover. I
suppose the "creeping effect" of HV over a smooth non-conduc-
tive surface comes into play when dealing with "constant"  HV
charges. And the higher rep rates of TC discharges would make
the charge more constant (higher duty cycle/less down time) so
a relatively "low voltage" would arc an impressive distance. Also,
the larger the Tesla coil, the larger the ionized "cloud" around the 
toroid, which further encourages more ionization of the surrounding
air i.e. longer sparks.

David Rieben



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