Re: dynamic power changing on TC

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

Original poster: "Jim Lux by way of Terry Fritz <teslalist-at-qwest-dot-net>" <jimlux-at-earthlink-dot-net>

Well.. it wouldn't be a good idea if you were trying to optimize output. 
But here, the idea is to restrict the output of the coil, and degrading the 
performance is exactly what you want.  The real question is whether it 
would produce a useful effect, and how many steps and how much dynamic 
range could you get.

The ideal would be something that could ramp 0-100% in steps of, say, 1%

Maybe a better solution would be a "staccato" mode tube coil and modulating 
the tube?  For a given DC power input, can a modulated tube coil produce 
spark effects identical (or very similar to) a conventional 
sparkgap/disruptive coil?

Does the damped sinusoid waveform of the disruptive coil lead to 
"interesting" sparks?

This might be more of a tube power amplifier driving the coil, rather than 
a standalone oscillator, since the classic oscillator type circuits have a 
"startup ramp" as the voltage in the tank builds up.  And, it would need to 
be quite beefy.. we're talking about a tube amp that puts out a power 
comparable to that in disruptive coil.  One might be able to duplicate the 
waveform by making the plate supply fed from a capacitor that holds one 
"bang" worth of energy and letting it droop during the pulse.

Let's see.. to duplicate the power handling of a 10 kW pig coil, you'd need 
a 10 kW class power tube, and, in the classic disruptive coil, the peak 
powers are a lot higher, because, while the average power may be 10 kW, the 
duty cycle is low. If you assume a Q=10 and fres=100 kHz this looks like a 
50-100 microsecond pulse. At, say 200 bangs/second (i.e. about 5 
milliseconds between bangs, the duty cycle is around 1%, so the peak power 
is on the order of a megawatt.....

That's starting to look like a radar modulator tube (and a good reason why 
spark gaps aren't such a bad design alternative!)

At 11:35 AM 1/15/2003 -0700, you wrote:
>Original poster: "Jason by way of Terry Fritz <teslalist-at-qwest-dot-net>" 
><jasonp-at-btinternet-dot-com>
>
>Jim,
>
> > Multiple primary taps with separate triggered gaps connecting them to the
> > primary capacitor.  You would fire the "optimum" gap to get the most
> > energy, and one of the "non-optimum" gaps to reduce the output voltage
> > (because the fres of the Pri and Secondary would be farther apart, and
> > you'd reduce output power), even though the primary cap energy remains the
>same
>
>Is this a good idea? I would have thought that de-tuning the primary circuit
>would cause more energy to remain in the primary due to incomplete transfer
>to the secondary, causing the primary RMS current to be higher and the spark
>gap to quench less well.
>
>Best R,
>Jason