Re: spark gap question...

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

Original poster: "Malcolm Watts by way of Terry Fritz <twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>

HI Marc,

On 29 Jun 01, at 8:07, Tesla list wrote:

> Original poster: "Metlicka Marc by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <mystuffs-at-orwell-dot-net>
> 
> jason,
> i didn't know anyone else has used a triggered gap on a tesla coil? the
> link to the pic doesn't work for me, but do you know if the gap was
> sync. with the line or did they use a variable pulse driver?
> 
> i think the biggest misconception about using the triggered gap is that
> it is just a fancy static gap, this is not so. also i think most don't
> believe that the triggered gap can quench at high currents, this is not
> so.
> i have successfully quenched the output of my 60-1 pig with 40 amp 240v
> input. i have also triggered the gap with my variable pulse rate and
> variable pulse width driver (which i blew up, i'm a terrible solderer)
> with good results and no problems.
> with sufficient air flow and a wide gap spacing the gap turns on and
> shuts off in relation to the trigger pulse with no problems.  using a
> dimmer and auto coil\cap setup the triggered gap syncs with the line
> just like a sync. rotary gap, but with only three pieces that are very
> cheap and easy to build. the dimmer also allows the gap to be phase
> adjusted to just the right "sweet spot" to give maximum output, it
> actually gives better output then my rotary on all my coils. it could be
> the chopping action of the triac while charging the tank, it could be
> the fact that there is no power arcing or no extended arc time? it does
> seem that this has something to do with it because when i was using my
> driver circuit, if i used long pulse widths it gave a discharge that
> looks more like my rotaries discharge.
> i would like to see more coilers give this simple gap a try, it is so
> easy and inexpensive that it is well worth it.
> personally i don't see any reason to build or use a rotary gap anymore?
> with a little pulse driver ingenuity, one could have an async and a sync
> gap in the same unit.
> i'm planing on finding someone that has better circuit building
> abilities then me to build me another driver and i want to get some
> quenching data on my scope, it is my opinion that the triggered gap will
> perform all the magical tricks that terry fritz stated his solid state
> gap would do.
> actually it would be more accurate to call it a "syncronous\asyncronous
> arc switch" because it turns on and off when you want, not when the tank
> energy falls below the ability to conduct and you're right in the fact
> that the triggered gap will force conduction and control low voltages, i
> have used it to fire my 1000v transformer at 60hz.
> marc m. 

I would just like to say that a scope waveform of your gap stopping 
the primary in its tracks would be most convincing. It is one thing 
to stop a power arc in the gap but quite another to kill a tuned 
circuit in full swing. By what mechanism does the driving circuity 
actually turn the gap off?

Regards,
malcolm