Re: 20 joules at 100 bps vs 4 joules at 500 bps

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Dmitry (father dest)" <dest@xxxxxxxxxxx>

Hello Malcolm.

Tl> Original poster: "Malcolm Watts" <m.j.watts@xxxxxxxxxxxx>
Tl>  > Original poster: "Dmitry (father dest)" <dest@xxxxxxxxxxx>

Tl>  > "high voltage helps to induce leaders from target objects" - how - by
Tl>  > mean of electrical induction? but following Kulon`s law the force,
Tl>  > acting at remote charge depends only from the toroid charge and
Tl>  > distance to the target. toroid charge could be made the same at any
Tl>  > secondary voltage - we only have to change toroid capacitance (primary
Tl>  > voltage, e.t.c.) actually we can`t consider toroid as a point charge
Tl>  > :-) but the field strength around the toroid  depends greater from its
Tl>  > ROC than from the secondary voltage.

Tl> If I understand correctly what you've said above, you would consider that
Tl> a large capacitance (e.g. conductive toroid) charged to a low voltage
Tl> would induce leaders from an object at some given distance to the
Tl> same degree as a low capacitance charged to a high voltage (same Q in
Tl> both cases)?

yes, it`s exactly the same as i wanted to say/ask - sorry for my
stupid english - Kulon`s law = Coulomb's law :-)

Tl>  I can't say I've observed that but then I can't rule it
Tl> out either not having done a definitive expt. It kind of goes against
Tl> "commonsense" but then commonsense has not proved to be reliable in
Tl> many areas either.

it`s just a question, i`ve not built any coil in my life - so this
statement could be an absolute nonsense :-)
let`s think logically - to make a leader from the target it must have
a big charge at small square - right?
to induce this charge we have to act with a big force at free charges
in the target - right?
the force according to Coulomb`s law is proportional to toroid
charge. field strength, generated with a toroid on a large distance is
proportional to the tor`s charge too. what`s not right in such
statement?

Tl>  > b.t.w. - how i must take into
Tl>  > account flashover voltage? imagine i`m building 4" coil, secondary
Tl>  > height 20", frequency at around 220khz - how could i know that
Tl>  > voltage? or - i`ve calculated the toroid voltage (70 cm diameter) -
Tl>  > 1.2 MV - what height should be the secondary to prevent flashovers?

Tl> There's a bit of suck and see.

oh no no no - i`ve no time, so i prefer to "read & see" :-)

Tl>  Mileage varies depending on
Tl> atmospheric conditions. Surface tracking also plays a part. I think
Tl> Greg Leyh's Electrum coil may have shown a tendency to flashover at
Tl> odd times and has an output approaching 1.5MV.

let`s see:
http://www.lod.org/Projects/electrum/techdata/electrumspecs.html

"SECONDARY COIL TOWER STRUCTURE
Lsec = 0.130H
Fsec = 37.92kHz (w/7' spherical electrode), 52.60kHz (no electrode)
Isec (pk) = 61A, with full primary voltage at 38kHz
Total tower height - 38' 8"

61 a means that bang energy = 241.86 joules - real "big bang", i love
this guy %-) total capacitance of discharger and the coil would be 135
pf, then secondary voltage is 1.9 MV. and 38' is not enough for such
voltage? i don`t believe - maybe some construction feature are
involved, maybe lack of thick coats of poly ^___^
and it seems that sphere protects the secondary worse than toroid:
http://www.lod.org/Projects/electrum/testing/pages/electrumeric.html

Tl> Flashover distances do not appear to follow a linear V/d curve.
Tl> Charge availability might well play a part - that's something
Tl> I've never looked at :(  Another coiler (Robert Stephens) killed a
Tl> tendency for one of his coils to flashover by placing a series of
Tl> acrylic disks along the length of his secondary to increase the
Tl> creepage distance, fluted insulator-style.

it`s widely used in power engineeringc, really - why not glue these
discs with a poly? the coil would look like a giant insulator :-)))
i must try this in the future - maybe then up to 6 secondary heights
would be shooted? :-)

Tl> I also observe that a secondary that is run just under its
Tl> flashover voltage in single shot operation is almost certain to
Tl> flashover in repetitive running at the same voltage.

but it`s the same as increasing streamer length by composition of
several bangs - residual ionization.

Tl> If you can quantify these things for me I'd be delighted.

no, not me, at least not before you :-)

-----
I am skeptical about space aliens too, but space aliens have a greater
probability of existence in my opinion than extra garage space...
(c) Richard Quick  6-07-95 03:59