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Re: Notches and things

Subject: 
        Re: Notches and things
  Date: 
        Fri, 28 Mar 1997 13:28:07 -0500 (EST)
  From: 
        FutureT-at-aol-dot-com
    To: 
        tesla-at-pupman-dot-com


>snip
> At very low power inputs where the toroid is just breaking out about 3"
> sparks there are four obvious notches before the quench. As I increase
> the power to maximum with the streamers out to 56", the quench seems to
> take place at the second notch. These two statements are on the basis
> that a notch is what I think it is.

Skip,     At high power with long steamers, more energy is being
delivered to
the sparks, causing energy to be drained faster from the primary tank
and
gap, and less energy is reflected back into the gap, so quenching is
easier
and jumps from the forth to the second notch.   A clue to whether you're
really seeing notches is the spacing between notches, at your frequency
and k
value the notches should be about 16 uS apart, and the first notch
should
occur at about 8 uS.   
 
> I obtain the scope pattern with the scope placed about 10' from the TC.
> The probe is connected to a 2' vertical wire attached to a ceiling
> rafter. The horizontal scan is set slow to display the energy packets
> which are at the mains frequency.
 
> The interesting part is that the rotary is only running at 1800rpm and
> the .25" contacts are on a 3.5" radius which gives a very long dwell
> time in the millisecond range. My question is how can I be getting a
> quench at the second notch with this long dwell time or don't I know
> what a notch is.

It is possible that the relatively loose coupling, the good-quenching
tungsten gaps you are using, are quenching BEFORE the physical dwell
time is
reached.  (I think I remember you saying you used tungsten.)  Of course
this
could occur with other materials also, but tungsten probably helps.  If
this
is happening, then the rotary is behaving more like a static gap (in a
sense)
by quenching due to energy reduction, deionization, cooling, and air
whipping.  And if so, this is great.  Rotaries are generally thought of
as
pulling and stretching out the spark, but in many systems, the energy is
depleted before the physical rotary dwell time is reached.
 
Coiling for today and tomorrow,

John Freau

> Comments appreciated
 
> Skip
  >>