Re: whats the largest VTTC?

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

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

In a message dated 1/18/03 3:06:59 PM Eastern Standard Time, 
tesla-at-pupman-dot-com writes:


>Original poster: "Daniel Barrett by way of Terry Fritz 
><teslalist-at-qwest-dot-net>" <dbarrett1-at-austin.rr-dot-com>
>
> > although the coronatron uses a lot of power, I didn't think the sparks
> > were particularly long because it operates on DC which gives a much
> > shorter spark length for a given input power.
>
>      Huh? Why would DC give a shorter aprk length per input power?
>db
>
>DB

,

I was speaking about filtered DC operation which gives shorter sparks
for a number of reasons.  First of all, when using AC, the coil is on
only half the time because it runs only during the positive half cycles.
This cuts the power input in half, yet the pulse rate is fast enough to
keep the sparks long.  Also, AC operation benefits from the
strong peak power of the AC peaks, while keeping the overall
1/2 cycle power relatively low.  In addition, the pulsed nature of the
AC spark promotes spark length growth better than filtered DC does.
Filtered DC gives a short bushy plasma-like spark that looks much
like the flame from a propane torch.  I would estimate that at least
four times more power is needed for a given spark length using
filtered DC compared to AC operation.  I believe that Robert Stephens'
Coronatron uses a filtered DC power supply.

John