Re: NST Resonant Charging?

To: tesla-at-pupman-dot-com
Subject: Re: NST Resonant Charging?
From: FutureT-at-aol-dot-com (by way of Terry Fritz <terryf-at-verinet-dot-com>)
Date: Thu, 15 Oct 1998 12:44:28 -0600
Approved: terryf-at-verinet-dot-com

In a message dated 98-10-15 03:20:31 EDT, you write:

<< Break Rate  Overcharge
 
> 240BPS  -    18%
> 120BPS  -    25%
>  60BPS  -   103%
>  30BPS  -   181%
>  15BPS  -   230%
 
> As I understand it, NST's are not designed to withstand
> even their own open ckt voltage indefinitely, let alone
> a voltage rise due to resonant charging.
 
> This suggests that perhaps a static gap which is firing
> erratically (thus producing a low BPS and a high overshoot) 
> may be the silent killer of marginalized NST's.
 
> IMO, resonant charging seems more a bug then a feature,
> especially if it cannot be used in the 200-plus BPS range.
 -- 
  
> -GL
 
Greg,

Thanks for this modeling data.

Even 25% voltage gain at 120 BPS is a good power increase.
I measured 32kV peak from a 12kV NST at 120 BPS (140volt
output variac), under resonant charging conditions.

I agree that the erratic firing of wide static gaps may destroy the
NST's, but I have not had a problem using sync gaps at 120 BPS,
even with old NST's.  I get good efficiency at the 120 BPS;  64"
sparks at 1570 watts.  

Very large coils may become inefficient at the low break rates because
of the large primary currents needed, I don't have the room to test 
this   :(    

John Freau