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Re: Tesla Magnifying Transmitter

Hi Liviu

>    Yes Nick, you has right, the value of breakdown in
> the dry air (3 kv/cm)is calculated for uniform
30kV/cm
> E-fields. And is not a brown common used fertiliser,
> is a yellow one. Doesn't know anyone a formula of
> breakdown voltage in AC fields or it is empirical
> found?
You simply map the e-field in your gap - any degree level physics text will
tell you how to do this.  As long as the field across the entire gap is
above 30kV/cm then it'll probably break down.
The discussion of the very long spark is quite different, on a macroscopic
scale it is not a simple breakdown calculation, it is a gradual growth
thing.  The E field close to the terminal is high enough to ionize the air,
so corona forms around it.  This has the effect of extending the terminal,
and as hysteresis effects have now come into play, of creating a few
seperate streamers, these have a very small radius at their tip which
creates a high enough E field to extend it further.  It is this stage which
relies on current, as a lot of charge is needed to maintain this amount of
air in an ionized state, whereas fairly little voltage is needed just to
create corona around a sharp point (Fairly little that is by TC standards)

Regards
Nick Field

> >
> >
> On Sat, 08 Jan 2000 12:32:09 -0700, Tesla List wrote:
>
> >  Original Poster: "Jim Lux" <jimlux-at-jpl.nasa.gov>
> >
> >  I think the breakdown field for air is pretty
> constant (at a given
> temp
> and
> >  pressure, etc.) however what is very tricky to
> model is the actual
> voltage
> >  and charge at the end of the leader, so what is not
> all that
> reliable is
> >  the actual field (in Volts/meter).
> >
> >  That said, there is a wealth of empirical data on
> long HV sparks for
> all
> >  sorts of electrode configurations in all sorts of
> environments. And,
> there
> >  are "rough and ready" approximate theories that fit
> the data (even
> if
> they
> >  don't describe what is actually happening) to allow
> some sort of
> reasonable
> >  guess to be made about what will happen. As long as
> you are happy
> with
> 10%
> >  accuracy, life is good.
> >
> >  Books like Craggs and Meek, and more recently,
> Bazelyan and Raizer,
> provide
> >  a fairly good handle on this.
> Could the title and publisher of the Bazelyan and
> Raizer book be
> repeated. I
> accidently deleted that entry from mail.
>
> Also Nick states:
>    The minimum voltage is not 3kV/cm or some similar
> brown
> >  commonly
> >  > used fertiliser.  The calculation, when done as a
> field
> calculation, is
> >  > quite simple but not too reliable as the
> breakdown field gradient
> of
> air
> >  is
> >  > very variable.
> >  >
> >  > Regards
> >  > Nick Field
> I have recently produced rapid , high voltage,high
> frequency  violet
> discharges of 5 mm length  to an intervening small
> insulated water
> capacity
> from  a sort of resonant rise of voltage principle
> obtained from large
> inductance coils at 60 hz resonance and  wall voltage.
> My  amperage
> draw to
> the device was about 130 ma, but the q of the coil
> system is only
> around 30,
> supplying only a 3 to 4 thousand volt unobvious, or
> resonantly choked,
> potential to the process. To enable the higher
> voltages to be shown I
> employed a  series triple arc gap  with the large
> discharge in the
> middle
> shunted by a capacity to enable breakover or short
> discharges to
> develope by
> the rapid charging and discharging of that capacity.
> Is it safe to
> assume
> that this miniature lightening effect is  only around
> 1500 volts, given
> the
> 5mm length
> and the quoted 3 kv/cm arc over discharge value or
> breakdown voltage.
> Thanx for any info
> Harvey D Norris
>
>
> Binary Resonant System
> http://www.insidetheweb-dot-com/mbs.cgi/mb124201
>
>
>
>
>
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