Re: gaps on caps

From: 	Antonio Carlos M. de Queiroz[SMTP:acmq-at-compuland-dot-com.br]
Sent: 	Friday, January 09, 1998 4:10 PM
To: 	Tesla List
Subject: 	Re: gaps on caps

John Couture wrote:

>   It appears that the charging of the primary capacitor is actually charging
> to different amounts of voltage at each bang. This could cause the safety
> gap to fire at certain times. The different amounts of primary charging are
> dependent on the operating spark gap. The major characteristics of this gap
> that would affect the amount of charging are resistance and time of closure.
> I do not believe these characteristics have ever been researched and tables
> or graphs published for Tesla coils. I have seen articles on spark
> characteristics but they do not have any relation to Tesla coil operation.

The interaction between a rotary spark gap, the AC line voltage, and the oscillations
caused by the combination of the power transformer output inductance and the primary
capacitance can produce complicated patterns of irregular charging of the primary 
I have seen a program called "rotjit", written by R. M. Jamison, that runs
simulations that demonstrate this effect. The program can be obtained from
one or more Tesla sites in the WWW (I don't remember from where I got it).

Antonio Carlos M. de Queiroz