From: FutureT@aol.com
Date: Sun, 19 May 2002 10:44:22 EDT
Subject: Re: [TSSP] Racing arcs
--part1_18f.81dd3e8.2a191446_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 5/19/02 1:23:40 AM Eastern Daylight Time, paul@abelian.demon.co.uk writes: Paul, I thought I'd mention also that although magnifier resonators can show racing sparks, they don't seem to show the types at the bottom of the resonator, in the manner that 2 coil systems do, (if I remember correctly.) Rather, in the magnifier, the racing sparks seem to not favor the bottom. This would make sense, since a magnifier resonator is much like the upper part of a secondary in a coil coil TC, in its behaviour. Magnifier drivers show racing sparks too I think, and often a great amount of corona and streamers that creap along the insulating sleeves which are often used to insulate the primary from the secondary. The main way to control this is to make the driver larger. Drivers that are too small for the power level, tend to be plagued by flashovers, etc. In one of my magnifiers, which gave 80" streamers, a 5" spark could be drawn off the transmission line. So most of the voltage seems to be building up along the resonator. In Richard Hull's magnifier, he used a 1 foot long resonator, which gave an 11 foot streamer. To eliminate racing sparks on the resonator, he used 6" x 20" toroids at each end of the resonator. (I'm guessing at the toroid dimensions.) I'm not sure how close the opposing toroids came towards each other. Another much larger toroid was stacked over one of the 6 x 20 toroids, with a cone shaped piece of metal in between. In general for two coil systems, the spark length tends to increase as the coupling is increased. This suggests that more energy is reaching the secondary. This makes sense since the spark gap has less time to lose energy. This greater energy may directly be causing the racing sparks, by over-powering the winding in some fashion. Lowering a toroid tends to reduce the spark length, and also tends to stop racing sparks. This may be occuring due to a different mechanism as Paul suggested. But could some shielding effect be occuring? I think Richard Hull considered the toroids to be creating an electrostatic shielding that stopped the racing sparks. I'm not sure what evidence he had of that, or exactly how it was thought to work. Just thought I'd mention it. Another question that occurs to me is; do racing sparks begin with a turn-to-turn breakdown, or does the spark jump over a number of windings? Often, they appear to jump over and skip about an inch of winding or so, but maybe it's an optical illusion. If the sparks are jumping over windings, this would suggest an uneven voltage gradient on the secondary, due to higher frequencies in the winding. Another thing I was thinking is that maybe the racing sparks begin with a arc-short between two adjacent windings, and this short causes a pulse or ringing along the coil, which then propagates along the windings, causing more racing sparks, or extending the racing sparks. Does such an idea seem plausible? In one old test, when I replaced the short 9" tall secondary with a 12" tall secondary wound with thicker wire and fewer turns, the coil behaved like a completely new coil. I was able to obtain much longer streamers with no racing sparks. I think this was a simple case of the shorter coil being over-powered. Of course there still has to be an explanation of why the racing sparks occur where they do, and behave as they do. Racing sparks may form by a combination of mechanisms working together to stress the coil over its limits at certain spots? Comments anyone? Cheers, John > Gradient animations now added to the 'tunings and couplings' > page, > > http://www.abelian.demon.co.uk/tssp/pn040502/ > -- > Paul Nicholson, > --part1_18f.81dd3e8.2a191446_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 5/19/02 1:23:40 AM Eastern Daylight Time, paul@abelian.demon.co.uk writes:
Paul,
I thought I'd mention also that although magnifier resonators
can show racing sparks, they don't seem to show the types
at the bottom of the resonator, in the manner that 2 coil systems do,
(if I remember correctly.)
Rather, in the magnifier, the racing sparks seem to not favor
the bottom. This would make sense, since a magnifier resonator
is much like the upper part of a secondary in a coil coil TC, in its
behaviour.
Magnifier drivers show racing sparks too I think, and often a
great amount of corona and streamers that creap along the
insulating sleeves which are often used to insulate the primary
from the secondary. The main way to control this is to make
the driver larger. Drivers that are too small for the power level,
tend to be plagued by flashovers, etc.
In one of my magnifiers, which gave 80" streamers, a 5" spark
could be drawn off the transmission line. So most of the
voltage seems to be building up along the resonator. In Richard
Hull's magnifier, he used a 1 foot long resonator, which gave
an 11 foot streamer. To eliminate racing sparks on the resonator,
he used 6" x 20" toroids at each end of the resonator. (I'm guessing
at the toroid dimensions.) I'm not sure how close the opposing
toroids came towards each other. Another much larger toroid was stacked
over one of the 6 x 20 toroids, with a cone shaped piece of metal
in between.
In general for two coil systems, the spark length tends to increase
as the coupling is increased. This suggests that more energy is
reaching the secondary. This makes sense since the spark gap has
less time to lose energy. This greater energy may directly be causing
the racing sparks, by over-powering the winding in some fashion.
Lowering a toroid tends to reduce the spark length, and also tends
to stop racing sparks. This may be occuring due to a different
mechanism as Paul suggested. But could some shielding effect
be occuring? I think Richard Hull considered the toroids to be
creating an electrostatic shielding that stopped the racing sparks.
I'm not sure what evidence he had of that, or exactly how it
was thought to work. Just thought I'd mention it.
Another question that occurs to me is; do racing sparks begin
with a turn-to-turn breakdown, or does the spark jump over a
number of windings? Often, they appear to jump over and skip about
an inch of winding or so, but maybe it's an optical illusion. If the
sparks are jumping over windings, this would suggest an uneven
voltage gradient on the secondary, due to higher frequencies in
the winding. Another thing I was thinking is that maybe the
racing sparks begin with a arc-short between two adjacent windings,
and this short causes a pulse or ringing along the coil, which
then propagates along the windings, causing more racing
sparks, or extending the racing sparks. Does such an idea
seem plausible?
In one old test, when I replaced the short 9" tall secondary
with a 12" tall secondary wound with thicker wire and fewer
turns, the coil behaved like a completely new coil. I was able
to obtain much longer streamers with no racing sparks. I think
this was a simple case of the shorter coil being over-powered.
Of course there still has to be an explanation of why the racing
sparks occur where they do, and behave as they do. Racing
sparks may form by a combination of mechanisms working
together to stress the coil over its limits at certain spots?
Comments anyone?
Cheers,
John
Gradient animations now added to the 'tunings and couplings'
page,
http://www.abelian.demon.co.uk/tssp/pn040502/
--
Paul Nicholson,
--part1_18f.81dd3e8.2a191446_boundary--
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.