Re: Dwell time, etc

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: FutureT@xxxxxxx 

In a message dated 4/4/06 2:06:15 PM Eastern Daylight Time, 
tesla@xxxxxxxxxx writes:


> behind of flying electrode - this will provoke reignition.
> what should i do to have max of "+" with min of "-"?


Dmitri,

I don't know.


> > But Ed Wingate obtains quenching on the 1st notch at full power on
> > his magnifier.
>
> is that coil from Terry Blake`s ("Death Cage", "Inside of Cage of
> Death") videos, with badly corrugated foil toroid onto small spun
> aluminium one? these are good news, coz quenching at high k`s is more
> (time wise) difficult, so if Ed has managed this - we all must try to
> do the same or better, right? % )


I don't think Ed's magnifier's k is very high.  It's probably similar 
to typical
classic coils.  I calculated it one time, but I forget the results.
I think the effective k is about 0.17 or so.


> > During the initial tuning of the coil, the sparks may have been
> > weak.  This would have made the gaps run hotter and may have made it
> > seem that a more elaborate gap system was needed than was actually
> > needed.
>
> probably. trying to cope with bouncing back and forth 60KVA may be even
> lethal % )
>
> >>as for 8 electrodes in series - probably somewhere in the end of '96
> >>Greg had been spoken about some of his rules of the thumb - 5kv at one
> >>gap maximum
>
> > I have my own rules of thumb.  I use two gaps for up to 30kV.
> > Maybe things need to change at higher powers.  I have no idea.
>
> yeah -  rules of real big thumb probably : )
>
> > In any case it's good that you challenge and question things.  It
> > prevents bad myths from developing.
>
> sorry, but i can only ask questions yet - no acces to real hardware -_-
> so i want to ask about this:
>
> "Date: Sun, 12 Oct 1997
> [...]
> I remember on one coil, I used 1/4" electrodes and I got thumping in
> the pole tranny and the system drew 16 amps.  When I went to an
> "offset" method that effectively reduced my dwell time to zero, the
> thumping went away, and the current dropped down to 13 amps, but spark
> length remained the same.  Break-rate was about 600 presentations per
> second.
> [...]
> John Freau"
>
> what was that ""offset" method"?


There were two fixed electrodes at opposite sides of the rotor which
had 8 spinning electrodes.  Normally the two fixed electrodes would
be 180 degrees apart.  But instead I moved one in such a way
that there was less than 180 degrees between the electrodes
going around the rotor on
one half, and more than 180 degrees going around the
rotor on the other half.  So the result was that when one
set of electrodes began to align, the other set of electrodes
at the other side of the rotor were moving away from alignment.
There was never a time when both sets were simultaneously
aligned.  I should mention that the electrodes were on the
edge of the disc not on the side of the disk.
Others on this list have tried this offset method also.

John


> -----
> ... If all else fails... Connect another (better if it would be brand
> new : D) storage scope across it! : )