Re: TC Questions

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

Original poster: Jim Lux <jimlux-at-earthlink-dot-net> 

At 07:47 AM 1/6/2004 -0700, you wrote:
>Original poster: "gtyler" <gtyler-at-drummond-dot-org.za>
>Hi,
>     I am involved in electronic design but I see that that does not
>qualify me to build a TC! There are many things to learn before I can
>even begin. Can some one explain this to me please.
>     What happens after the spark gap "fires"? does the arc continue for
>the rest of the mains 1/2 cycle? If so there will be 1 pulse of HV every
>1/2 cycle, and the current flowing after the spark gap fires is waisted.
>Also the repetition rate will be 100 or 120 hz.?
>
>George

The charging impedance for the cap is fairly high, so the gap fires, and 
discharges the cap through the primary L, it rings down, keeping the gap 
alive for a few cycles. Then, the gap quenches, and the cap charges up, 
relatively slowly in comparison.

In a DC coil, there's some current limiting device in series with the 
supply (a big choke, usually).

In the run of the mill AC coil, we rely on the series impedance of the 
transformer (which is very high for a NST, and is apparently high for a 
pole transformer (because of the primary ballasting).  Pole transformers 
often are used with rotary or air blast gaps, which helps turn off the arc.