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

Hi Ken,

At 10:38 AM 04/16/2000 -0700, you wrote:
>Terry (& all)-
>
>Boy!...it seems as if between us we've flogged this horse if not to death
>at least into a coma!  

Rest assured, this horse is far from dead!  It's lasted for over 100 years
and we aren't going to kill it over night ;-))

>Your Ken05 is exactly what I see.  

Great!  One major hurdel in this stuff is getting two people to get
consistant results in two differnt places.

>Looking at
>Ken10, I think that Antonio's point in his posting of today is operative,
>in the case of the top-loading shown in the "lumped" waveform:  The
>slowing down of the "lumped" response is due to having to charge up the
>probe's capacitance-to-ground.  And no doubt the same thing happens when
>one has a "real" top load attached.

My coils self capacitance is 9.3pF.  Obviously, sticking a 16.6pF probe on
top has a dramatic effect on it.  I cannot convert my plane antenna to
higher sensitivity without messing the response up.  Since the voltage is
high, one should be able to use a probe with much less load...

>
>Having forgotten the transmission-line theory I at least temporarily
>learned 50 years ago, I don't have a notion as to why the probe
>capacitance will advance the transmission-line wave.  Can you explain
>that in terms adapted to the meanest understanding?

Not being any genuius on T-line stuff myself, I "think" I can!  

Take a coax 100 feet long with a velocity factor of 66%.  The 1/4 wave
frequency is 1.6MHz.  The current travels from one end of the line to the
other in 154nS.  

Now, put a big capcitance on the end to 'drop the resonant frequency' to
0.8MHz (1/4 wave time is now 313nS).  The wavelength is doubled but the
current 'still flows through the line in same 154nS' but the wave time is
313nS.  The current still gets to the end of the line in 154nS but the 1/4
wave point is 313nS.  So the wave appears at the end of the coax in only
1/8 of the wave length time.  The current still goes from one end of the
coax in the same time but we have dropped the system frequency down so the
wavelngth is now longer.  It still takes the same time(154nS), but in
relation to the now longer wavelength it looks like it gets there early.
At least that is what I think is the explanation...

Cheers,

	Terry

>
>Ken Herrick