Re: NEW Direct Coupled Tesla Circuit - Looks promising

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Harvey Norris <harvich-at-yahoo-dot-com> 


--- Tesla list <tesla-at-pupman-dot-com> wrote:
 > Original poster: "Malcolm Watts"
 > <m.j.watts-at-massey.ac.nz>
 >
 > Hi Dan,
 >
 > On 15 Dec 2003, at 11:56, Tesla list wrote:
 >
 >  > Original poster: "Mccauley, Daniel H"
 > <daniel.h.mccauley-at-lmco-dot-com>
 >  >
 >  >
 >  > A friend of mine and myself came up with a new
 > directly coupled tesla
 >  > circuit which from initial looks and simulations
 > looks to be able to
 >  > overcome the limitations of previous direct
 > coupled tesla resonant
 >  > circuits and may easily outperform the standard
 > tesla coil.  Sounds
 >  > too good to be true?  Possibly, but time will
 > tell.  The only pitfalls
 >  > of this circuit are the high voltage requirements
 > of a few components
 >  > including the spark gap.
 >  >
 >  > I've enclosed a sketch of this topology.  Any
 > comments are
 >  > appreciated.
 >  >
 >  > http://users.snip-dot-net/~liche/directtesla01.jpg
 >
 > Difficult to tell without some key component values.
 > It looks similar
 > in principle to some of Tesla's schemes from the
 > CSN. How exactly do
 > you envisage its working principles (apart from the
 > obvious)?
 >
 > Malcolm
It seems obvious to me that the gap is across the
capacity, but not across the LC loop primary, and also
then not represented as a short to the HV supply in
the form of an arc gap. CSN notes the following, with
added comments...

The first record Of Tesla's high frequency coupled
oscillatory circuit with an air cored transformer is
to be found in patent 454622
of 23 June 1891 under the title "System of electric
lighting". The oscillator converts low frequency
currents into "currents of very high frequency and
very high potential" which then supplies single
terminal lamps. (from Aleksandar Marincic's CSN
preface) The arc gap in this schematic is within the
tank circuit, something later abandoned as the best
method.

On July 2,1899 Tesla notes the reasoning for this; In
a
schematic showing the break within the tank circuit he
comments... "the scheme of connections has the
disadvantage that the primary discharge current passes
through the break hence, the resistance of the latter
being large, the oscillations are quickly
damped and there is besides a large current through
the break which makes good operation of the latter
difficult. To prolong oscillation in the primary and
increase economy one of the schemes before
considered may be resorted to." He then refers to the
conventional approach of allowing the break to be
shunted across the hv secondary outputs where he
comments.. "in this arrangement the currents through
the break device are much smaller and the oscillations
started by the operation of the break device continue
much longer." Tesla makes no comment concerning the
idea of placing an inverse tank circuit on the
other side of the break in the first example for a
center tapped high frequency transformer. In that
situation two (180 phased) primaries
would recieve their oscillations from a single arc
gap. The problem of the arc containing the entirety of
the currents is then circumvented by the pathway
established along the sides of the newly
configured figure 8 LC quantities. Likewise the same
approach would mean that a three phase primary high
frequency transformer could also use a "shared arc
gap" used simultatneously by three oppositely phased
TC secondaries, predictably at some time period to
show a ring or arcing in space.

HDN