Re: safety gaps at high power

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

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 1/6/01 3:43:15 PM Eastern Standard Time, tesla-at-pupman-dot-com 
writes:

> John F. -
>  
>  You stated "If the gap slows down and the voltage starts building up
>  resonantly". I believe this is a possibility and have mentioned it in the
>  past but I have never made the tests to prove it. Have you or any other
>  coiler made these tests?

John C,

I seem to remember that happening a number of times on my coils;
the rotary slows.... the safety gap fires.  I think others have reported
the same thing.

>  
>  Variations in the gap operation would account for the various random spark
>  lengths issuing from the secondary terminal. This results in a varying
>  output load which makes the typical random spark output of little use for
>  engineering purposes.

In the 120 bps sync gap systems I use, the firing voltage and bang
size are extremely constant from bang to bang.  Despite the constant
bang size, the spark length varies over time.  This is because the
sparks grow from bang to bang by re-igniting previous streamer
paths.  The process is somewhat random.

>  
>  This is why I am encouraging the use of another type of test and that is
>  using the controlled spark test. These are the types of tests that are
>  needed to arrive at a resonable "watts per foot of spark" rating to
>  correctly compare tesla coils.

Well it all depends on what you're trying to compare, and your
reasons, etc.

John Freau

>  
>  John Couture