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Re: That secondary behaviour, E-Tesla5, and Corum's thing...

Hi Robert,
                In here you outline the exact problem I have with *one* of 
the Corum's claims, namely the instantaneous propagation bit. I 
have it written in black and white from the authors that during 
primary dwell, the primary is coupled to the entire secondary and so 
makes the secondary behave as a lumped circuit. I know the 
coupling from one end of a typical resonator to the other is 
practically nil so bearing that in mind -
         Suppose you have constructed a primary such that it is a 
single turn the same diameter as the secondary and placed directly 
below the first turn of the secondary. Any argument you make about 
the coupling of the bottom turn of the secondary to the top turn must 
also apply to the coupling between the primary and various portions 
of the secondary. So why should the secondary behave any 
differently when it is coupled to the primary? That is an explicit claim 
that I have read in their notes. I was amused to read about the 1/4 
wave measurements being made with link coupling to the signal 
generator in their latest paper. Where does that leave the original 
claim?  Perhaps they have reconsidered and thrown that bit of it 
away?  Another question might also be posed - why does a 
supposedly lumped coil (not a typical TC resonator) exhibit spurii?

         I only have problems with some of their theory, not all of it.

Regards,
Malcolm

> Original Poster: "Robert Jones" <alwynj48-at-earthlink-dot-net> 

<snip>
 
> First I should restate my views. The theory is not mine even Tesla reported
> it.
> 
> In its usually operation a Tesla coil secondary resonates due to the
> reflections of signals from what is normally the high voltage end in a
> similar way to a 1/4 wave antenna or any quarter wave stub (as it is
> referred to when not used as an antenna). A good analogy is how an organ
> pipe resonates. The coils behaviours as a classical transmission line due to
> its distributed capacitance and inductance which result in the comparatively
> slow propagation of ALL SIGNALS along the axis of the coil.  Typically a
> thousands of time slower than the velocity along a wire or coax cable.  The
> resonance occurs if the reflected signal returns to the driving end with the
> opposite polarity to that of the driving signal.  For an open circuit
> transmission line the minim length at which this can occur is 1/4 of a
> wavelength. If the line is terminated with capacitance, inductance or a
> short circuit the phase of the reflected signal is modified and hence the
> line will resonate at a different length. It can also resonate at odd
> multiplies of a 1/4 wave length again due to the phase of the reflection.
> The fundamental requirement for this to occur in the average Tesla coil at
> say 100KHz is the slow propagation of signal along the axis of the coil.
<snip>