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Re: First big magnifier run
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> From: Tesla List <tesla-at-poodle.pupman-dot-com>
> To: Tesla-list-subscribers-at-poodle.pupman-dot-com
> Subject: Re: First big magnifier run
> Date: Friday, February 07, 1997 2:26 AM
>
> Subscriber: nikki-at-fastlane-dot-net Fri Feb 7 00:04:09 1997
> Date: Wed, 5 Feb 1997 05:51:02 -0600 (CST)
> From: Bert Pool <nikki-at-fastlane-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: Re: First big magnifier run
>
> At 10:25 PM 2/4/97 -0700, John Freau wrote:
> ><< monster snip
> >>What was absolutely incredible during this "conventional coil" attempt
is
> > >that we had some extremely hot, violent arcs from the toroid down to
the
> > >primary. Sometimes, but not every time when this happened, we got 23
inch
> >>flashovers from the bottom of the primary to the concrete driveway! We
have
>
>
> [snip]
> >
> >Great preliminary results with that Maggy! I can suggest two
possibilities
> >for why the spark missed the pipe. 1) the concrete is a bigger target,
and
> >the sparks and charged fields may not "see" the small pipe. 2) (and
maybe
> >more likely), TC sparks develop their length by the "growing" principle.
> > Bylund had done some work with this using his solid state coil, and he
found
> >that certain conditions favor the production of sparks that do not "go
for
> >ground", but instead have a mind of their own, so to speak. I think it
was
> >his conjecture that it's very different than a DC spark, in the sense
that
> >the voltage is much lower for the distance jumped than would be expected
when
> >compared with DC spark jumping distances.
> >
> >When the spark is first formed, it is short and cannot reach the pipe
or
> >ground or anything, therefore its direction of propagation is random.
From
> >the tip of the spark, the spark then grows longer from the continuing
power
> >input to the system, but again, the added amount of spark is weak, too
weak
> >to reach any target, again its direction is random. This random growing
> >continues until the spark IS long enough to reach something, but what it
> >reaches is random due to the gradual, incremental increase in the spark
> >length.
> >Comments welcomed.
> >
> >Looking forward to full power results!
> >
> >John Freau
> >
>
> Nice reply John. It wasn't that the spark grew in length, then had to
> choose either my copper tubing ground or concrete, it had to literally
arc
> _around_ the grounded copper line to even reach the concrete! It is
obvious
> the concrete was the preferred ground, it is a really massive
counterpoise,
> what with the rebar and all. I am beginning to suspect also that the
length
> of the copper line must have had a lot to do with it as well - I am going
to
> change out the 3/8 line with 2 inch wide copper strap next run, and I am
> going to bury a couple of ground rods as well.
>
> Bert Pool
> nikki-at-fastlane-dot-net
I have a theory as to why such a strange thing as the above may occur. I do
not think that the action is related to DC resistance, but to high
frequency inductive and electrostatic effects which combine to make the
path through the concrete an easier path than through the 3/8 inch copper
line and the Big Ground.
Let me illustrate my theory with a dumb ascii drawing:
/
/_ Nasty RF Spark
/ trying to get
home
/ to Mother
Earth
Mr. 3/8 inch copper tubing
------------------------------------------ TC System Ground
| Note that this forms
| a 1/2 turn inductor! __________________________Moist
Concrete
____|________________________________________________________
/ / / Good Old Mother Earth / / / / / / / / /
/ / / / / / / / / / / /
Really Really Good Really Really Good
Earth Ground Via Earth Ground Via
Underground Pipes Good Old Mother Earth
OK, now pretend that *you* are a very high voltage narrow pulse width
spark, and you have your choice of going through the 1/2 turn inductance of
the TC System Ground or straight through the air and moist concrete to a
very close large flat capacitively coupled surface known as Good Old Mother
Earth. Which way are *you* going to go home to mommy? Why through the lower
impedance circuit, of course.
>From the spark's point of view, the large surface area just below the TC is
much easier to get to. It has a much lower AC impedance. Recall that to
pulses even a small inductance such as 1/2 of a turn will appear as a very
great resistance. So wy should it take the path with extra impedance when
ground is right below it. It is, after all, the *same* earth ground with
two paths. The spark just takes the easiest one.
It is also interesting to note that the TC System Ground *was* doing its
job! If it had *not* been connected, then the spark would not have had a
good foothold to push off from in the first place. It's just that once it
was pushed off, it found a shorter return path than *we* might have
originally thought was available. Or, to phrase it another way, the reason
the spark was so insistent on getting to ground through the concrete was
that it *was* properly connected to ground in the first place. Once the
spark was in existence and had fired off the top of the coil, it just
insisted on being lazy and returning by the lowest impedance path it could
find.
Just my opinion.
Fr. Tom McGahee