- View SourceHi All, My name is Harvey D Norris and to start things off a breif

history is in order. I am the Author of the Binary Resonant System

with homepage at

http://msnhomepages.talkcity.com/LaGrangeLn/teslafy/Homepage.html

I am interested in tesla coils, and adapting this special arc gap to

their operation. To describe this we must first consider the ordinary

center tapped transformer, which will be dealt with a little better

in the next post. The center pathway is shared by two 180 phases that

produce a net cancellation of current on that path, provided the

opposing sides of currents are equal. For the thing I am talking

about, the inverse situation applies where one resonant tank circuit

will be divided into two, with a center pathway shared by both

reactive sides from opposite directions, leading to the observation

that twice the current exists on that pathway than on the sides

alone. It is therefore a figure 8 tank circuit, that no one but

myself apparently is willing to work on. To make this into an arc gap

one merely needs the opening at the center of the 8. This opening

itself will procur a voltage rise, if the circuit is tuned to the

source frequency. The problems of this application to a tesla coil is

the fact that that circuit is not tuned to the source frequency, but

rather the secondaries resonant frequency. It is good now to explore

what Tesla himself invented, with some practical hints for a dual

spiral binary resonant arc gap.

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.

So here I am making some conceptual suggestions upon

implementing the "third schematic arc gap" apparently

neglected by Tesla as a possibility. This is described

using dual identical spirals. The usual reply that

this is already accomplished by a bipolar tank circuit

does not take into account the fact that in the

"third" schematic possibility there are two and not

one capacities involved.

I am still working to try a NST gap like that. Cant

take that much longer.

I have made some preliminary modeling ideas using the

dual spirals available at Radio shack as their flat

stranded 50 ft insulated for a mini-tesla coil

primary. I'm trying mine in a bipolar application for

a mini tesla coil one would suppose that length of the

wire is is small in comparison on the smaller mini

secondary, thus making the operation at a high

frequency. Since the duration of that rf burst is then

a very small time period,I am aiming for a very high

bps rate which this system should permit. Here are

some considerations of difference in tuning with a

single arc, oscillating two primaries 180 out of phase

as I have described as a Binary Resonant System,(BRS)

1)Because magnetic agreement between the primaries is

necessary for the maximum inductance, and the currents

on the primaries themselves are 180 out of phase, and

the further fact that the spirals themselves are not

themselves bifilar with respect to each other: to make

the fields in agreement means that opposite outer and

inner coil connections to the repective opposite hv

terminals is necessary. The inner and outer leads of

the dual spirals that remain are in turn connected to

capacities which connect in series with the opposite

hv potential. This then consists of two oppositely

phased series LC quantities in parallel which is the

current limiting condition before gap firing.

2) The arc gap is made from the connections at the

midpoints of the 180 phased series LC quantities, or

the ends of the inner and outer wire spirals that are

not connected to the hv secondary. Thus upon arcing

the resistance of the primary is on either side of the

arc: the arc is not directly shunted to the hv ouput.

3) The capacities on each side are NOT made from the

resonant frequency calculated from that sides L

quantity, but rather the quantity established by the

needed capacity to resonate with both L quantities in

mutual inductance where the primaries are in series to

determine this new L(total). A C(total) is then

matched to this new L figure to resonate, and each

side will recieve twice C(total). This is because

these capacities will appear in series when the gap

fires, thus to arrive at C(total) twice the value must

be used in series.

4) Because of the dielectric qualities of the

insulation between windings the spiral set also has a

internal capacitance, and adding capacitance on each

side of the LC quantites may not change the resonant

frequency as suspected. Since the set then has a

recorded C internal capctance of 220 pf, and a

measured .636 mh L quantity correctly wired in series,

a natural resonant frequency of 425,000 hz might be

suspected. A scope measurement of this frequency seems

to indicate 588,000 hz including the 25 pf scope

capacitance.

5) It may be possible to simply connect the inner and

outer spiral ends together at an arc gap and have the

primary resonate at its own natural resonant frequency

established by its internal parameters. Of course then

one would have no tuning and be limited to placing the

correct secondary to resonate in place.

HDN