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Re: BL Saga

Hi Richard, all,

> Original Poster: Richard Hull <rhull-at-richmond.infi-dot-net> 

<snip>

> >       I have to correct something I earlier said also: I reported
> > that I had found an error in the Corum's ITS Notes. There is indeed
> > an incorrect formula in there but it appears that they used the
> > correct one further down the track so their theoretical conclusion
> > about resonator coherence time stands. The formulaic error may have
> > been a typo or transcription error. However, I have still not seen
> > resonator coherence happening on the scope despite numerous attempts.
> > I stand by my other comments.
> >
> > Apologies all,
> > Malcolm
> 
>   Malcolm,
> 
> I have noted a "resonator fill time" associated with the H2 thyratron
> circuits -on my scope.  I have heard the Corums lecture on this and I
> might assume this the the coherence interval.
> 
> It only occurs when there is zero swapping of energy back to the primary
> (half cycle cut off - as in the H2 Thyratrons.)
> 
> This last weekend at the Teslathon here in Richmond, Dr. Mark Rzesotarski
> & I noted it again with Mark's antenna setup modeled after Terry Fritz
> suggestions.  It is a nearly full cycle lag. as the resonator builds to a
> maximum voltge output.
> 
> In these systems the primary has no tuning effect at all as I have noted
> before. Also, the decrement is slow and extends over about 50
> oscillations with the big toroid on it. A lot of the coil Q is realized.
> In addition, a lot of the initial energy is wasted without the beating.
> 
> On a different subject,  We also noted with my scope that my magnifier
> 11E which was run at about 1KW (reduced power) just prior to break out
> went through about 4-5 beats before quenching.  Again, I have noted this
> before here on this list.
> 
> Richard Hull, TCBOR

Last night I read their notes again for the umpteenth time and still 
got the impression that resonator fill time is distinct from 
coherence. They made an explicit note to this effect in the ITS Notes.
      My understanding: the argument is made by them that during 
ringup (or resonator fill?), the resonator behaves as a lumped 
circuit exhibiting a uniform current throughout its windings (how it 
could possibly be identical at the top and bottom with no topload is 
beyond me). They argued (in the notes) that this uniformity was due to
the primary coupling to the entire resonator. Well it does - sort of.
k at the top as we all know is a tiny fraction of what it is at the 
bottom if one measures it. However, they then say that once the energy 
is trapped therein by primary gap quench, over a period of time 
(coherence time) the current changes from being uniform to being a 
maximum at the base and minimum at the top. As a result, voltage 
gradient across the windings also changes from being linear (I x Xl) 
to assuming a non-linear gradient (sinusiodal presumably). The 
voltage is always going to be ideally zero at the bottom in the two 
coil system so that doesn't change but what does (they say) is the
volts/turn across different portions of the winding. The difference 
in total output voltage is claimed to be VSWR vs Q (i.e. rises to 
about 1.3x the fully rung-up value). That's how it reads to me anyway 
and whatever the final value is claimed to be, Ken C. reinforced this 
view in some email to me. It is this redistributed voltage rise that 
I have been looking for and failed to find. He claims it is easy to 
see. I never have. Perhaps I have it all wrong but the implication to 
me is that if the system quenches at the end of the second ringup and
system losses are low enough, voltage some time down the track 
(Tcohere) will rise to a value that might exceed the value it reached 
at the end of the first ringup. Perhaps somebody can throw some light 
on this. I've never seen any rise beyond natural ringup rise in 
dozens of tests. They claim it happens in the normal course of events 
in a standard two-coil system after gap quench.
     If anyone knows of an experimental setup that would allow this 
to be seen, I would be most grateful to hear from you.

Regards,
Malcolm