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RE: [teslafy] Re: Wye Coil

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  • David Thomson
    ... windings would be producing magnetic cancellation. This is what we want isn t it? What is a longitudinal wave? I m not sure what will happen just yet,
    Message 1 of 10 , Jan 31, 2002
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      >To make a comment on trifilars coupled to alternator three phase, then the
      windings would be producing magnetic cancellation.

      This is what we want isn't it? What is a longitudinal wave? I'm not sure
      what will happen just yet, but if I don't try it I'll never know.

      There are a couple ways to finish a wye coil. One is to keep all three
      leads together, the other is to terminate them at 120 degrees apart from
      each other. When they are terminated at 120 degrees, the inductance on each
      lead is slightly different from the others. On my wye coil I have 6.20mH,
      6.23mH, and 6.25mH. The slight difference in inductance may either setup a
      rotating magnetic field, or result in a dud. I'm not sure how that will
      work just yet either.

      >It is good that you have also noted the reduction in resonant frequency
      with spirals, which was ~ 4/1 on the 4 wind model I made.

      This is still a mystery to me. Tesla was adamant all through his life that
      quarterwave is the resonant frequency of the coil. Tesla mostly worked with
      flat spirals. I know the guys on pupman who routinely work with cylinder
      coils say quarterwave is not necessarily the way to go to get big sparks.
      Of course Tesla only tried to get big sparks at Colorado Springs as a
      photography thing to dazzle his potential investors. His real aim was in
      setting up resonant fields in the earth and tuning for maximum power
      transmission. In his patents, Tesla is partial to the flat spiral coil.
      His Wardencliffe tower employed flat spiral coils for transmitting and
      resonating the earth. He must have known something about flat spiral
      secondaries that we have not yet discovered.

      I believe this hidden knowledge is related to the odd characteristics of a
      flat spiral secondary and one of those characteristics is that the measured
      resonant frequency does not match the quarterwave, in fact it is about 1/4
      as you noted. Further, the calculated inductance of the flat spiral
      secondary is 1/3 the measured inductance for a single wind.

      I find the ratio of 4/3 in another aspect of flat spiral secondaries. In
      order to get the maximum inductance from a given length of wire, the average
      radius should be 4/3 of the width of one side. I verified this
      mathematically. I'll need to write a paper on this mathematical analysis
      and post it. To get the maximum inductance for a given diameter, you would
      wind the coil from the center out. This is why all Tesla's flat spirals are
      wound from the center out. Where the 4/3 rule comes in handy is when
      designing a flat spiral primary for a helical coil. The size of the flat
      spiral primary should be calculated to the 4/3 rule and the diameter of the
      solenoid coil should be based on the available space within the inner
      diameter of the resulting flat spiral primary.

      The world of flat spiral secondaries is loaded with easy to breach
      frontiers. There will be many new discoveries in the coming years based on
      these coils.

      Dave


      David Thomson
      dave@... <mailto:dave@...>


      -----Original Message-----
      From: harvey norris [mailto:harvich@...]
      Sent: Thursday, January 31, 2002 5:55 PM
      To: reply@...
      Cc: teslafy@yahoogroups.com
      Subject: [teslafy] Re: Wye Coil



      --- David Thomson <dave@...> wrote:
      > Hi Harvey,
      >
      > It has been brought to my attention that you are
      > interested in a wye wound
      > secondary. I produce these coils in flat spirals.
      > It would be possible to
      > wind a cylindrical coil in the same manner. I
      > haven't yet tested the coil
      > with 3 phase power, but I will as soon as I can find
      > an automobile
      > alternator I can rewire. I believe the flat spiral
      > form of the wye coil
      > will produce some unusual effects. I have already
      > tested this coil in
      > different ways with single phase power through a
      > 15KV 60mA NST. You can see
      > my journal at
      >
      http://www.tesla-coil-builder.com/FlatSpiralSecondaryTrifilar.htm.
      EXCELLANT SITE!
      > I have also started a new group specifically for
      > flat spiral secondaries.
      > It is at http://groups.yahoo.com/group/spiralcoils/
      >
      > Dave
      >
      > David Thomson
      > Volantis
      > dave@...
      >
      Will be joining shortly.
      To make a comment on trifilars coupled to alternator
      three phase, then the windings would be producing
      magnetic cancellation. It might be amusing to ground
      them at distant triangulations to produce hf standing
      waves in the earth. Then each trifilar winding would
      have to act as a one ended condition sheme, with the
      earth between the points as the wye connection. That
      situation should prevent the expected large currents
      that would be expected to occur if the wye assembly
      were merely attached to the 3 phase alternator, in
      which case, its impedance being mostly nullified might
      be difficult to resonate from those alternator inputs.
      If in fact it were possible to resonate windings of
      this nature, it would mean employing huge capacitites.
      However nothing is really known till you try it. Marc
      Metlica is interested in trifilar secondaries, I will
      forward your EXCELLENT web site to him.

      It is good that you have also noted the reduction in
      resonant frequency with spirals, which was ~ 4/1 on
      the 4 wind model I made. I find it unusual that your
      final tuning indicated the best action at the higher
      frequency nearer to the quarter wavelength.

      Sincerely HDN


      =====
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    • harvey norris
      ... Some immediate long comments concerning the longitudinal wave; from past writings... The method I am using to record natural resonant frequencies may seem
      Message 2 of 10 , Feb 1, 2002
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        --- David Thomson <dave@...> wrote:
        > >To make a comment on trifilars coupled to
        > alternator three phase, then the
        > windings would be producing magnetic cancellation.
        >
        > This is what we want isn't it? What is a
        > longitudinal wave? I'm not sure
        > what will happen just yet, but if I don't try it
        > I'll never know.
        Some immediate long comments concerning the
        longitudinal wave; from past writings...

        The method I am using to record natural resonant
        frequencies may seem unusual, as are some of the
        claims. First of all I recognize that frequency is
        relative to the capacity being used in the measurement
        , which always occurs when we use the scope as a
        measuring tool. The resonant frequencies that can be
        picked up by the 60 hz plate method, are in the same
        range as picked by by the alternator 480 hz. rod
        method.(~500 khz for dual return wired windings of 100
        ft spirals) The plate method at 60 hz is to create an
        arc gap of miniscule proportions using long copper
        bars, with the edge surface areas placed close
        together. Two of these are created for each opposite
        180 phased resonant potential, and the 4 bars made
        with a larger gap between them. It is the large gap
        between them that makes for the better one sided
        application. A wire leading to a plate area ,
        connected to one of the inner bars will add its polar
        capacity to the existant conventional capacity created
        by bar proximities at distances to small to
        conveniently measure. The net result of this is that
        the plate area connection will usually cause arcing to
        occur on the applied set of bars, and sending the the
        plate areas into electric field oscillations of high
        frequency, by the respective connections to that arc
        gap. Inductors placed around this plate can record
        different frequencies coming from the same plate,
        because that high voltage arc between the bars is in
        many ways a quenched arc that starts and stops many
        times faster than the conventional twice per cycle arc
        gap firings used for tesla coils. A one ended
        vibration from one potential only is thus enabled. Now
        another method past the arc gap method, is to simply
        use a short neon bulb, in place of the arc gap. The
        neon is the routed directly from one potential, with
        its ending on the plate area, thus it is a one wire
        circuit. What this does is act as a buffer to the
        vibration, making its rf bursts in time, less
        sporiadic, and more cohered in timing, similar to the
        water /glass medium enabling hf with no arcing also
        making the rf bursts to cohere themsevles better in
        time periods. The neon method however shows about a 5
        to 10 fold reduction in signals above the plate, by
        scope measurements of inductors placed over the
        plate.The neon essentially damps or regulates the
        vibrations of potentials and established currents
        between the real resonant potential and the polar
        capacity of the ending plate. These things easily work
        from the 60 hz resonant system, because of the high q
        of the system, and the available voltage application
        of the source, which for alternator work is limited to
        30 volts, and possibly equivalent acting q factors.
        However the one ended polar methods are not readily
        shown for the 480 hz voltages. Instead both ends of
        the circuit are used. It is these endings that
        consists of the plate areas, and intervening SrFe
        volume. This plates consists of rf burst emittors,
        that with lower voltage inputs can be seen with
        respect inductors around the space of these emmitors.
        The first hurdling block of reasoning is the use of a
        ferrite fashioned rod as an alternator powered high
        frequency source. Generally as it has been noticed,
        currents can be passed through geometries of SrFe, as
        an interphasal load. It was noticed that high
        frequency emanations come from a ferrite rod fashioned
        in this manner, and apparently the source frequency is
        being changed into high frequency as the currents
        propagate through the piece. This causes numerous
        meter problems. In the case of the amperage meter
        recording the ferrite conductions several problems
        developed, to the point where it completely failed to
        give readings. Two points of operational discrepancies
        were noted before that failure. The normal 40 to 60 ma
        conduction could be read, but not on the 400 ma scale
        that enables that range to be read. One must switch to
        the lower range of 4 ma to get the reading. Another
        aspect was that the meter MUST be turned on before the
        alternator is turned on, as the prior existance of
        these hf currents are made in the no field condition,
        and if the meter is turned on from that point, it is
        incapacitated. Meters attempting to show amperage from
        spatial resonant coils also display these amperage no
        reading problems, and a scope sensoring of the fields
        those coils display show hf ringdowns on the main
        cycles, thus we can conclude easily that hf causes
        problems for digital AC amperage meters. In one case
        of stator voltage measurement being made from spatial
        resonant coils, the voltage meter itself went into an
        oscillation, blinking its display on and off very
        rapidly. This is the cheaper RS meter, that normally
        shuts off after 3 minutes.This oscillation however did
        not quit, and you could not shut the meter off. The
        next day the battery was disconnected from the meter,
        still producing its blinking display. Reconnecting
        the battery restored the meter to normal operation.

        Now to continue here, it is the orientation of the
        inductor to recieve flux change that indicates the
        polarization of the emmittor. Typically the emmittor
        for the plate example has a rapidly changing electric
        field in the space above the plate. A changing
        electric field also has a counterpart changing
        magnetic field produced in space, but it is at right
        angles to the electric field that generated it. Thus
        the correct orientation for the inductor to again
        translate this changing magnetic field into the
        induction for a changing electric field so that the
        sensor coil itself appears as a source of emf, the
        orientation of that inductor must then be with the
        loops containing the secondarily created magnetic flux
        change. It is here that distinct differences are
        noticed by the geometries of the inductors that can
        pick up the rf signals from the plate. Near the plate
        area, the signals are not polarized in two dimensions,
        but three. This means the orientation of the inductor
        can be in the wrong dimension to pick up the signal.
        That is essentially my definition of longitudinal emf
        on the recieving end, but this description gets more
        invoved when we start to understand how to apply this
        same 2 dimensional wave progation from that with a
        metal plate issuing hf electrical vibrations from one
        potential only, to the 3 dimensional hf vibration. One
        may wonder how one can make such a transition, since
        the effects coming off the metal plate are already in
        3 dimensions! The answer to this is to put the same
        inductor in the magnetic field around the coils that
        are making these series bipolar voltage rises, and
        instead to see what the magnetic fields are doing. One
        in fact will see practically no disturbances in those
        coils magnetic fields, where the sensor may only pick
        up a breif spike on the 60 hz sweeping rate, thus we
        see that this hf high frequency electric field process
        barely disturbs the magnetic fields that go about in a
        clean oscillation at 60 hz freq. Notably it is also
        observed that only one of the two coils are being
        subjected to allowing the resonant voltage rise in
        turn vibrate the polar electric field effects as a one
        wire delivery. This is because only one arc has been
        procurred from one resonant potential, and it has been
        used in a polar application.
        To actually throw the comparatively large magnetic
        fields of the oppositely resonant phased 60 henry
        coils into high frequency from the source frequency,
        it becomes necessary to use both opposite potentials,
        and to form an arc gap between them. Now evertime this
        gap fires, the sensor coil will record its rf burst.
        The purpose for using this square loop inductor is
        that it produces a phenomenal reduction in its
        generated standing wave, or how it interprets the rf
        burst contained now in the actual magnetic field
        lines all around the space of the coil system in 3
        dimensions, whereby in the first example these effects
        were confined to the relatively smaller space around
        the polar field plate. Now we can discover the scalar
        nodes that exist, even though no actual magnetic field
        cancellation takes place at the sourcing of these
        effects.

        I dont blame folks for shaking their heads saying how
        can you have a scalar effect, if you arent putting
        anything into cancellation. Indeed because of the fact
        that each coil is separately phased in its resonance
        and made 180 out of phase, to operate the system in
        unison for magnetic field agreement means that using
        identically wound coils, one coil must be turned
        backwards with respect to the other, so they will
        appear in bifilar relationship with one another, but
        they are generating fields in oscillation in unity and
        not opposition. Note that this is identically inverse
        to the example of a center tapped bifilar transformer
        secondary that takes the same core flux change and
        makes 180 phased emfs, which can be combined together
        for twice the voltage that exists in only a single
        sided application. Here because of oppositely phased
        resonant volatge rises, the voltage at the arc gap
        will also be twice what each system has risen to. Once
        this gap fires the coils become parallel resonant to
        the source frequency. Generally the impedance of the
        system rises to 4q squared the former values, which
        for the 60 hz BRS using 60 henry coils means that
        onece the gap fires, all the resonant rise of voltage
        will disappear, and the amperage demand from the
        system will decrease 600 fold. This causes the arc gap
        to act in a manner so that it rapidly quenches, and
        reforms to strike again. In contrast to tesla coil
        secondaries which generally operate at 2 rf
        bursts/cycle, this kind of system may permit many more
        than 2 rf burst/cycle, and additionally the L and C
        quantities are not arranged to resonate at some higher
        frequency as occurs in the tesla tank primary, but
        instead they arranged to resonate at the SOURCE
        FREQUENCY.

        Thus it should not be amazing that no frequency is
        being transmitted, but if we had to classify it that
        way, we would have two options. We could say that it
        is being transmitted at 60 hertz, and the rf can be
        seen riding on the 60 hz signal with some types of
        inductors used as recievers. However we could also say
        that since the coils have 9 miles of wire, the
        quarterwavelength vibration would be about 5000 hz,,
        which becomes 2500 hz at arc gap fire, but it is also
        known that interwinding capacitance in the 20,000
        turns of 23 gauge wire should also considerably reduce
        that figure. In any case we have a system emmittor
        that conveys rf into space, but not at a specific
        frequency, and where the recievers simply ring at
        their own resonant frequency.

        Further investigation of this effect shows that the
        square wide loop inductor can be placed in the area of
        the large coils opening, or polar area. We can record
        the 60 hz signal to scope, and see that turning the
        inductor sideways so that the loops encompassing flux
        change no longer do so results in dimunition of the
        signal. Now we can repeat this observation for the
        coils set in single arc gap mode, where the magnetic
        fields themselves will go into high frequency. We will
        now have a spike on the cycle for every gap firing.
        Turning up the sweep rate of the scope we can see the
        rf ringdown on that inductor. It will in fact have a
        sinusoidal shape, and be recieved in the conventional
        orientation to recieve flux change. If we now rotate
        the inductor in the polar area of a coil, as
        before,turning the inductor sideways to the field
        lines it now does recieve a rf signal! That is the
        longitudinal rf IMBEDDED in the conventional, where
        the positions itself of the inductor in the space
        around the coil system will determine if it is
        recievable. In the polar area of the coil these two
        distinct types of rf signals can be seen 4 times per
        coil (hand)rotation, so the rf effect is not uniformly
        located, indicating a form of polarization. In
        addition to this there are also two types of
        longitudinal signals that can be recieved, since
        orthogonal rotations of the loop are also possible in
        more than two dimensions. The longitudinal signals
        have a high frequency riding on the first half wave
        cycle of the rf decay itself.

        Where the nodes come into effect will occur as we take
        the sensor inductor in the conventional orientation in
        a trip through space around the coils to reach the
        opposite coil pole. Keeping the loops of the coil
        perpendicular to the imagined magnetic field lines, we
        may note that 3 times on the journey nodes exist,
        where the sensing of the rf bursts by the inductor
        vanishes.
        It is at these nodes that turning the loops 90 degrees
        so that they are facing the coil system, will then
        reveal that the node is in fact no node at all, but
        contains the longitudinal reception noted by that
        shape of that wave. Now the occurance of these nodes
        where the conventional rf vanishes, and the
        longitudinal expresses itself can even further
        explored. These occur on the equatorial plane and also
        on planes made from the top and bottom of the coil
        system. The effect was explored from the equatorial
        plane, where the inductor is turned with its loops
        facing the coil system. Here it was found that as the
        loops were moved outwards from the coil system yet
        ANOTHER NODAL effect revealed itself. The longitudinal
        emf disappears, but again turning the inductor in the
        orientation to recieve conventional rf will show that
        signal. So by these analogies it should be seen that
        in fact how we can say the longitudinal waves can be
        inbedded in conventional rf, and how and what
        longitudinal conveys.

        In any case, from what the scope shows, one should be
        able to create a AIR CORE LONGITUDINAL RF TRANSFORMER.
        For the 60 hz model this would involve wrapping
        windings 90 degree to the windings, so that the
        secondary coils encompass a toroid around the
        multiwound solenoidal primary. Trying to accomplish
        this is fairly rediculous however. However rediculous
        things may start to sound possible with the
        combinations of spirals and alternator inputs. So here
        I gladly stop going so off subject and suggest some
        real possibilties here.

        The first of these are rather sensible. No magnetic
        cancellation will be employed. Only 2 of the 3
        alternator phases and two of the trifilar windings
        will be used. Each opposite end of trifilar winding
        will be initially connected backwards with respect to
        each other into 2 of 3 delta phased outputs. This
        situation does the reverse of ordered phasing. In this
        way the new increased impedance each pathway sees can
        be tuned to, by giving each phase an identical
        reactance. Thus each spiral winding can be sent into
        resonance at the source frequency, and not employing
        magnetic cancellation. The next step starts getting
        problematic, as an arc gap must be set up between the
        resonances. It may be that the voltage rise in one
        stage from the 6 mh spirals may be insufffient to
        drive these coils into a high frequency, straight from
        the stator outputs. In this case a preliminary voltage
        rise must then be interposed betweeen the stator and
        the spirals. The aim here will be to simply test this
        model as an rf emmittor constructed similar to the 60
        hz BRS. Once a functioning arc gap were made, the
        third wire of the trifilar becomes the solitary
        secondary wind ot the rf transformer, where
        conveniently the length of that winding is the same as
        half of the transmission system.

        Once the output of that winding can be determined, it
        will tell us important things. Namely one, it will be
        a reciever of conventional rf, but the process that
        emits this rf should also emit longitudinal emf. This
        has been shown in the 60 hz case with massive amounts
        of wire length enabling the possibility of resonating
        the circuit at source 60 hz frequency, and enabling
        high frequency effects without the use of a step up
        transformer, where arcing processes can be made from
        mere wall voltage, and the increase of voltage
        necessary for arc gap operation instead made by
        resonant rise, instead of transformative. But here as
        referenced it is nigh near impossible to employ this
        60 hz resonance case for a 6 mh coil, but readily
        possible for the 60 henry. It is nigh impossible to
        put torroidal winds on the 60 henry coils, however it
        is very possible to do this for the spirals. Thus by
        the combinations of using higher frequency alternator
        sourcings and spiral design where it becomes easier to
        add a secondary as torroidal winding, the testings for
        a LONGITUDINAL RF TRANSFORMER could be made. The
        first consideration would then become to wind sections
        of 100 ft as toroidal winds across the primary. The
        problem now becomes the fact that identical wire
        lengths as recievers no longer applies for the
        torroidal winding, as the standing wave is determined
        by interwinding capacitance and geometry also,and in
        fact a 500 ft winding may not be the most effective.
        But this would be done merely to verify that this
        longitudinal transformation of emf via bifilar arc gap
        can indeed take place. Then it can be compared to that
        made by the conventional spiral as a reciever,and any
        phasing differences for these signals determined,
        where in fact it might even be possible to conbine the
        conventional and longitudinal signals together.

        I have refered to this bifilar arc gap also as a MARX
        TANK,for TC usage, because of the voltage doubling
        that should occur at arc gap. This is different from
        a Binary Resonant System, because the 4 L&C quantities
        are not then resonant to the source frequency, but are
        selected to be resonant to the secondary of a tesla
        coil.Thus once that element of energy transfer in that
        ways and means is accomplished, undoubtably the next
        challenge would be to construct the primaries IN THE
        SAME FASHION as two sets of torroidal winds
        encompassing the inner and outer volumes of space
        around the center spiral secondaries, and then to
        operate those secondaries in the conventional way of
        testings that has gone on. But it still becomes
        perplexing what to do with three secondaries as per
        tesla coil usage!

        In any case I would be interested in making or buying
        trifilar spirals to make tests like these, for the
        simple reason that they look like good tools for the
        investigation of possible longitudinal signals, and
        their transmission. When the 4 L and C quantities are
        selected to be source frequency resonant, everytime an
        arc gap firing takes place there is a conversion from
        series to parallel resonance. It gets a bit confusing
        but a series resonance is also 180 out of phase with
        its parallel resonant counterpart having 4q squared
        less amperage demand.(for 180 phased series resonance
        vs figure 8 Tank made by arc gap) So for every rf
        burst/cycle every this unusual short duration arc
        occurs, the polarity of the magnetic fields must
        completely collapse and emerge in the opposite
        polarity in that time period, causing a maximum amount
        of flux change to be recieved by the third
        conventional winding.

        In line with all the threads about longitudinal emf,
        here is the conventional take on the subject
        http://www.df.lth.se/~snorkelf/Longitudinal/node1.html

        Sincerely HDN


        =====
        Tesla Research Group; Pioneering the Applications of Interphasal Resonances http://groups.yahoo.com/group/teslafy/

        __________________________________________________
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      • harvey norris
        ... Never thought about that one. Is your secondary spirally wound with this ratio? Terman s 1937 Radio Engineering apendix notes the inverse way the
        Message 3 of 10 , Feb 1, 2002
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          --- David Thomson <dave@...> wrote:

          > I believe this hidden knowledge is related to the
          > odd characteristics of a
          > flat spiral secondary and one of those
          > characteristics is that the measured
          > resonant frequency does not match the quarterwave,
          > in fact it is about 1/4
          > as you noted. Further, the calculated inductance of
          > the flat spiral
          > secondary is 1/3 the measured inductance for a
          > single wind.
          >
          > I find the ratio of 4/3 in another aspect of flat
          > spiral secondaries. In
          > order to get the maximum inductance from a given
          > length of wire, the average
          > radius should be 4/3 of the width of one side. I
          > verified this
          > mathematically. I'll need to write a paper on this
          > mathematical analysis
          > and post it. To get the maximum inductance for a
          > given diameter, you would
          > wind the coil from the center out. This is why all
          > Tesla's flat spirals are
          > wound from the center out. Where the 4/3 rule comes
          > in handy is when
          > designing a flat spiral primary for a helical coil.
          > The size of the flat
          > spiral primary should be calculated to the 4/3 rule
          > and the diameter of the
          > solenoid coil should be based on the available space
          > within the inner
          > diameter of the resulting flat spiral primary.
          Never thought about that one. Is your secondary
          spirally wound with this ratio? Terman's 1937 Radio
          Engineering apendix notes the inverse way the
          relationship can be stated, in the section on
          inductance of a flat spiral;the maximum inductance
          with a given length of wire is obtained when the
          radial depth of the coil is three fourths the mean
          radius. I guess it sure does make a difference to
          design the secondary from an existing primary so that
          this ratio can be preserved. However in your unique
          spiral secondary tesla coil, with trifilar secondaries
          even!, which is somewhat baffling, this ratio if one
          exists does not appear to resemble the inverse
          situation, as you have built it. Apparently with the
          tuned operation you are indicating, you are only using
          about 1/4 of the available primary winding. I would
          consider trying the toroidal primary approach, since
          you dont appear to need all that much primary
          inductance, and you could then possibly use all the
          lengths of primary, where now you are using 1/4 of the
          amount. HDN


          =====
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        • Mikael Bi
          Please explain me the concept of quater wave lenght..I know the calculation of if, but I don t understand the concept behind. ...
          Message 4 of 10 , Feb 1, 2002
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            Please explain me the concept of quater wave lenght..I
            know the calculation of if, but I don"t understand the
            concept behind.
            --- harvey norris <harvich@...> a écrit :
            <HR>
            <html><body>


            <tt>
            <BR>
            --- David Thomson <dave@...> wrote:<BR>
            <BR>
            > I believe this hidden knowledge is related to
            the<BR>
            > odd characteristics of a<BR>
            > flat spiral secondary and one of those<BR>
            > characteristics is that the measured<BR>
            > resonant frequency does not match the
            quarterwave,<BR>
            > in fact it is about 1/4<BR>
            > as you noted.  Further, the calculated
            inductance of<BR>
            > the flat spiral<BR>
            > secondary is 1/3 the measured inductance for
            a<BR>
            > single wind.<BR>
            > <BR>
            > I find the ratio of 4/3 in another aspect of
            flat<BR>
            > spiral secondaries.  In<BR>
            > order to get the maximum inductance from a
            given<BR>
            > length of wire, the average<BR>
            > radius should be 4/3 of the width of one
            side.  I<BR>
            > verified this<BR>
            > mathematically.  I'll need to write a paper
            on this<BR>
            > mathematical analysis<BR>
            > and post it.  To get the maximum inductance
            for a<BR>
            > given diameter, you would<BR>
            > wind the coil from the center out.  This is
            why all<BR>
            > Tesla's flat spirals are<BR>
            > wound from the center out.  Where the 4/3
            rule comes<BR>
            > in handy is when<BR>
            > designing a flat spiral primary for a helical
            coil. <BR>
            > The size of the flat<BR>
            > spiral primary should be calculated to the 4/3
            rule<BR>
            > and the diameter of the<BR>
            > solenoid coil should be based on the available
            space<BR>
            > within the inner<BR>
            > diameter of the resulting flat spiral
            primary.<BR>
            Never thought about that one. Is your secondary<BR>
            spirally wound with this ratio? Terman's 1937
            Radio<BR>
            Engineering apendix notes the inverse way the<BR>
            relationship can be stated, in the section on<BR>
            inductance of a flat spiral;the maximum inductance<BR>
            with a given length of wire is obtained when the<BR>
            radial depth of the coil is three fourths the mean<BR>
            radius. I guess it sure does make a difference to<BR>
            design the secondary from an existing primary so
            that<BR>
            this ratio can be preserved. However in your
            unique<BR>
            spiral secondary tesla coil, with trifilar
            secondaries<BR>
            even!, which is somewhat baffling, this ratio if
            one<BR>
            exists does not appear to resemble the inverse<BR>
            situation, as you have built it. Apparently with
            the<BR>
            tuned operation you are indicating, you are only
            using<BR>
            about 1/4 of the available primary winding. I
            would<BR>
            consider trying the toroidal primary approach,
            since<BR>
            you dont appear to need all that much primary<BR>
            inductance, and you could then possibly use all
            the<BR>
            lengths of primary, where now you are using 1/4 of
            the<BR>
            amount. HDN<BR>
            <BR>
            <BR>
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          • David Thomson
            Hi Harvey, ... I haven t wound one to this ratio yet. That was going to be my first coil winding, but then I noticed that almost all of Tesla s coils go all
            Message 5 of 10 , Feb 1, 2002
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              Hi Harvey,

              >Is your secondary spirally wound with this ratio?

              I haven't wound one to this ratio yet. That was going to be my first coil
              winding, but then I noticed that almost all of Tesla's coils go all the way
              to the center.

              >Apparently with the tuned operation you are indicating, you are only using
              about 1/4 of the available primary winding. I would consider trying the
              toroidal primary approach,

              Toroidal primary? I haven't heard of that. What does it look like?

              Yes, my coil only needs 1 3/4 turns of the primary for optimum spark.
              Interestingly, this is exactly as Tesla shows his flat spiral primaries in
              his schematics. I always had thought this was for convenience. Maybe it is
              just coincidence, but I will remain aware of this ratio in future coils.

              Dave

              David Thomson
              dave@... <mailto:dave@...>
            • harvey norris
              ... I am again unsure if I understand the 4/3 ratio, what do you mean by length, is this diameter? I also misunderstood your meaning of starting from the
              Message 6 of 10 , Feb 2, 2002
              • 0 Attachment
                --- David Thomson <dave@...> wrote:
                > Hi Harvey,
                >
                > >Is your secondary spirally wound with this ratio?
                >
                > I haven't wound one to this ratio yet. That was
                > going to be my first coil
                > winding, but then I noticed that almost all of
                > Tesla's coils go all the way
                > to the center.
                I am again unsure if I understand the 4/3 ratio, what
                do you mean by length, is this diameter? I also
                misunderstood your meaning of starting from the center
                out. Does this mean little or no inner area? In your
                example you stated, I interpreted this way;which may
                not be what you were trying to indicate,

                Given four equal sections of radii outwards from the
                center, the first section is the beginning of the
                spiral outwards comprising the remaining 3 sections.
                The inner section then becomes the radius of the
                secondary, which is basically Termans def. for max
                inductance for a given spiral inductance applied to
                the primary. I see now that by definition of mean
                radius you may be talking about something else.
                > >Apparently with the tuned operation you are
                > indicating, you are only using
                > about 1/4 of the available primary winding. I would
                > consider trying the
                > toroidal primary approach,
                >
                > Toroidal primary? I haven't heard of that. What
                > does it look like?
                Probably a mistaken conception and waste of time, but
                usually justifiable with constraints. It isnt very
                sensible because the windings would be orthogonal with
                respect to each other, or at right angles.
                Conventional em has loops of magnetic flux made so
                that flux change is the causitive mechanism for energy
                transfer. Years ago I had constructed a poorly tuned
                TC of some good size, but using the wrong components
                and ratios, this was 1500 ft of 14 gauge wound on a 20
                inch diameter Sonotube and only yeilded 2-3 inch
                arcing. Later on I also constructed a 7 ft diameter
                loop around the TC as an outdoor project, and placed
                500 ft of the same wire with a large spacing between
                wires. You could stand inside this loop and turn the
                central TC coil on, but it was definitely not the
                sensation one would have if that loop were not there.
                One was actually then inside a larger high frequency
                process, as you would not touch others outside the
                loop with a florescent in your hand without shocking
                them. The outer loop in fact would produce 1/4 inch
                arcing when its end terminals were brought close
                together. Thus we can conclude that the majority of
                (magnetic)flux change of thew central TC coil did not
                cross the wires of the outer loop, but yet significant
                voltage was generated. A freind was amazed by this,
                saying that he thought the mechanism for energy
                transfer was the changing electric field and not the
                magnetic, where that didnt make any sense to me, since
                the fields are coupled to each other as reflections to
                begin with, and the basic laws already tell us it is
                the flux change within the loop will produce a
                proportionally smaller emf as we go outward, and the
                magnetic lines do not have to cross the wires of the
                reciever as in conventional induction.

                Now back to the idea of a toroidal primary winding, or
                the idea in general. It has been shown in experiments
                the rf decays of energy can be made with recievers in
                the orthogonal reception, vs the conventional
                reception that occurs. In fact, how do we not know
                that if copper tubing fashioned as orthogonal loops
                bisecting the interior of a coil consisting of winds
                surrounding that tubing section, does not model the
                idea of windings surrounding a monopole radio
                antennae, provided we simply enclose the actual arc by
                the coils! In this case the importance of the
                secondary loops that are no longer encompassing
                magnetic flux, the idea then progresses to the fact
                that we must instead make them encompass electric
                flux. Thus we must place the highest voltage points of
                the tank circuit IN THE SPACE OF THE SPIRALS INTERIOR
                VOLUME. Here is where the advantage of using the Marx
                Tank Primary becomes evident. We can generally procure
                twice the voltage discharge with respect to the source
                voltage using the method of charging two capacities in
                parallel, and then to discharge them in series. The L
                quantities are the primaries attached to each
                capacity, to complete their opposite circuit
                connection. Each of these capacities then have
                connections to each opposite potential, and an
                intervening L to accomplish the conduction. Two
                primary loopings, made bifilar with respect to each
                other, then can have a meeting point inside the
                interior spiral volume, so that one arc gap stright
                between the primaries will accomplish two bifilar
                primaries making magnetic fields in unity. Now who can
                say in itself that if we simply put the normally noisy
                TC arc gap inside a collection of loops, that those
                loops will not themselves convey emf? The position of
                those primaries to convey actual magnetic flux might
                be accomplished by tilting that angle of the primary
                with the spiral secondary, where then instead of
                vertical winds with respect to the spirals, they might
                be made at 45 degrees, and then the parameter of this
                amount of lateral aggreement with the secondary could
                be the mode of how much mutual inductance between
                primary and secondary exists. Now we first then
                conclude that NO mutual inductance exists when the
                windings are orthogonal or a right angles. Wouldnt it
                then be something if one could get a functioning coil
                to work when it isnt supposed to! So if it doesnt
                work, blame yourself for knowing why it doesnt work,
                and dont waste the time making something you already
                know wont work. But just imagine the amazement that
                can occur on finding out it can work. One would think
                that the fact of emeploying the arc itself within the
                spiral might have some effect. But since I have not
                yet tried these things, It can remain pure
                speculkation for now. HDN
                > Yes, my coil only needs 1 3/4 turns of the primary
                > for optimum spark.
                > Interestingly, this is exactly as Tesla shows his
                > flat spiral primaries in
                > his schematics. I always had thought this was for
                > convenience. Maybe it is
                > just coincidence, but I will remain aware of this
                > ratio in future coils.
                >
                > Dave
                >
                > David Thomson
                > dave@... <mailto:dave@...>
                >
                >
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              • David Thomson
                ... calculation of if, but I don t understand the concept behind. For all the years Nikola Tesla made high voltage coils, he always found that quarter wave
                Message 7 of 10 , Feb 2, 2002
                • 0 Attachment
                  >Please explain me the concept of quarter wave lenght..I know the
                  calculation of if, but I don"t understand the concept behind.

                  For all the years Nikola Tesla made high voltage coils, he always found that
                  quarter wave length wires produced the best results for him.

                  To get the highest resonant rise of potential (highest voltage,) it is
                  necessary for the impedance at the base of the coil, where the secondary
                  meets the ground, to be zero. The coil best suited for a zero ground
                  impedance is the quarter wave coil since the voltage node is at ground (zero
                  volts.) From voltage node and upward is just part of the wave, however.
                  There is also a wave portion equal to the upper wave, from the ground down.
                  This downward wave portion is a mirror of the upward wave portion.

                  This is why Wardencliffe needed such an extensive underground grounding
                  system. Tesla needed to easily sink 50 million volts of negative potential
                  into the ground and just as easily project 50 million volts of positive
                  potential into the atmosphere. He chose the large flat spiral coils for his
                  primary and secondary coils. His secondary coil also connected to other
                  spirals, free of mutual inductance with the primary/secondary transformer
                  stage. The total wire length of all the spirals above the secondary would
                  have been equal to one quarter of the wavelength had he not had a top
                  capacitance. That large tower added enough capacitance to the secondary
                  circuit that Tesla was able to use an odd multiple of the quarter wave
                  length instead.

                  But regardless of the size of the coil or the amount of power put into it,
                  it is essential that the point where the wave passes from atmosphere to
                  ground equals zero volts. Otherwise the system is unbalanced and difficult
                  to bring into resonance.

                  It's important to realize that the quarter wave frequency is a general rule
                  for a secondary coil with no top capacitance (or very little capacitance.)
                  As the top load is increased, the length of wire can be reduced. Tesla made
                  sure the top load was sufficient that the wire length was an odd multiple of
                  the quarter wave length. That is if you started with a wire 300 feet long
                  in your Tesla coil. The same frequency can also be resonated on a wire 100
                  feet long with the correct extra capacitance on the terminal. In the 300
                  feet wire example, the wave is traveling not only the 300 feet through the
                  wire, but also 300 feet into the ground. Traveling the full distance of 600
                  feet, the wave has traveled half of a cycle. It then travels back up the
                  system to the top of the coil for a full 1200 feet of distance for one full
                  cycle. Thus the wire in the coil is just 1/4 the total distance the wave
                  will travel (or an odd multiple thereof.)

                  This is why a good ground is essential for operating a Tesla coil connected
                  to ground. You can also operate two identical coils and use one to act as
                  the ground. So if you had a 300 feet long secondary coil and built an
                  identical coil to use in place of the ground connection, the wave will
                  travel its full cycle without use of a ground. This is the theory behind a
                  bipolar coil. The total wire length in a bipolar coil is half the
                  wavelength and the primary is situated in the middle of the secondary. The
                  resonant frequency is calculated accordingly.

                  In the bipolar coil it is easy to see why the voltage needs to be zero at
                  the halfway point. If one coil were longer than the other, then the system
                  can not resonate. The same holds true for a grounded coil. If the voltage
                  node is not exactly at ground, then the system will not fully resonate.

                  I hope this helps.

                  Dave

                  David Thomson
                  dave@... <mailto:dave@...>
                • Mikael Bi
                  yes thank you very much, so it is possible to make a bipolar coil. so does it mean that if I want to make work a coil say 24.7 Mhz about 10 feet long wire,
                  Message 8 of 10 , Feb 2, 2002
                  • 0 Attachment
                    yes thank you very much, so it is possible to make a
                    bipolar coil. so does it mean that if I want to make
                    work a coil say 24.7 Mhz about 10 feet long wire, that
                    would mean I would need and other 10 feet coil as a
                    ground, how would it be connected??


                    --- David Thomson <dave@...> a écrit :
                    <HR>
                    <html><body>


                    <tt>
                    >Please explain me the concept of quarter wave
                    lenght..I know the<BR>
                    calculation of if, but I don"t understand the
                    concept behind.<BR>
                    <BR>
                    For all the years Nikola Tesla made high voltage
                    coils, he always found that<BR>
                    quarter wave length wires produced the best results
                    for him.<BR>
                    <BR>
                    To get the highest resonant rise of potential (highest
                    voltage,) it is<BR>
                    necessary for the impedance at the base of the coil,
                    where the secondary<BR>
                    meets the ground, to be zero.  The coil best
                    suited for a zero ground<BR>
                    impedance is the quarter wave coil since the voltage
                    node is at ground (zero<BR>
                    volts.)  From voltage node and upward is just
                    part of the wave, however.<BR>
                    There is also a wave portion equal to the upper wave,
                    from the ground down.<BR>
                    This downward wave portion is a mirror of the upward
                    wave portion.<BR>
                    <BR>
                    This is why Wardencliffe needed such an extensive
                    underground grounding<BR>
                    system.  Tesla needed to easily sink 50 million
                    volts of negative potential<BR>
                    into the ground and just as easily project 50 million
                    volts of positive<BR>
                    potential into the atmosphere.  He chose the
                    large flat spiral coils for his<BR>
                    primary and secondary coils.  His secondary coil
                    also connected to other<BR>
                    spirals, free of mutual inductance with the
                    primary/secondary transformer<BR>
                    stage.  The total wire length of all the spirals
                    above the secondary would<BR>
                    have been equal to one quarter of the wavelength had
                    he not had a top<BR>
                    capacitance.  That large tower added enough
                    capacitance to the secondary<BR>
                    circuit that Tesla was able to use an odd multiple of
                    the quarter wave<BR>
                    length instead.<BR>
                    <BR>
                    But regardless of the size of the coil or the amount
                    of power put into it,<BR>
                    it is essential that the point where the wave passes
                    from atmosphere to<BR>
                    ground equals zero volts.  Otherwise the system
                    is unbalanced and difficult<BR>
                    to bring into resonance.<BR>
                    <BR>
                    It's important to realize that the quarter wave
                    frequency is a general rule<BR>
                    for a secondary coil with no top capacitance (or very
                    little capacitance.)<BR>
                    As the top load is increased, the length of wire can
                    be reduced.  Tesla made<BR>
                    sure the top load was sufficient that the wire length
                    was an odd multiple of<BR>
                    the quarter wave length.  That is if you started
                    with a wire 300 feet long<BR>
                    in your Tesla coil.  The same frequency can also
                    be resonated on a wire 100<BR>
                    feet long with the correct extra capacitance on the
                    terminal.  In the 300<BR>
                    feet wire example, the wave is traveling not only the
                    300 feet through the<BR>
                    wire, but also 300 feet into the ground. 
                    Traveling the full distance of 600<BR>
                    feet, the wave has traveled half of a cycle.  It
                    then travels back up the<BR>
                    system to the top of the coil for a full 1200 feet of
                    distance for one full<BR>
                    cycle.  Thus the wire in the coil is just 1/4 the
                    total distance the wave<BR>
                    will travel (or an odd multiple thereof.)<BR>
                    <BR>
                    This is why a good ground is essential for operating a
                    Tesla coil connected<BR>
                    to ground.  You can also operate two identical
                    coils and use one to act as<BR>
                    the ground.  So if you had a 300 feet long
                    secondary coil and built an<BR>
                    identical coil to use in place of the ground
                    connection, the wave will<BR>
                    travel its full cycle without use of a ground. 
                    This is the theory behind a<BR>
                    bipolar coil.  The total wire length in a bipolar
                    coil is half the<BR>
                    wavelength and the primary is situated in the middle
                    of the secondary.  The<BR>
                    resonant frequency is calculated accordingly.<BR>
                    <BR>
                    In the bipolar coil it is easy to see why the voltage
                    needs to be zero at<BR>
                    the halfway point.  If one coil were longer than
                    the other, then the system<BR>
                    can not resonate.  The same holds true for a
                    grounded coil.  If the voltage<BR>
                    node is not exactly at ground, then the system will
                    not fully resonate.<BR>
                    <BR>
                    I hope this helps.<BR>
                    <BR>
                    Dave<BR>
                    <BR>
                    David Thomson<BR>
                    dave@... <mailto:dave@...><BR>
                    <BR>
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                  • David Thomson
                    The bipolar coil would be connected identical to a normal coil. But you have made me wonder. I have a bipolar coil but connected the primary to earth ground
                    Message 9 of 10 , Feb 2, 2002
                    • 0 Attachment
                      The bipolar coil would be connected identical to a normal coil. But you
                      have made me wonder. I have a bipolar coil but connected the primary to
                      earth ground instead of the other side of the grounding secondary. I'm
                      going to try that and see what happens.

                      Dave

                      David Thomson
                      dave@... <mailto:dave@...>


                      -----Original Message-----
                      From: Mikael Bi [mailto:qtx_2000@...]
                      Sent: Saturday, February 02, 2002 4:33 PM
                      To: teslafy@yahoogroups.com
                      Subject: RE: [teslafy] Re: Wye Coil



                      yes thank you very much, so it is possible to make a
                      bipolar coil. so does it mean that if I want to make
                      work a coil say 24.7 Mhz about 10 feet long wire, that
                      would mean I would need and other 10 feet coil as a
                      ground, how would it be connected??


                      --- David Thomson <dave@...> a écrit :
                      <HR>
                      <html><body>


                      <tt>
                      >Please explain me the concept of quarter wave
                      lenght..I know the<BR>
                      calculation of if, but I don"t understand the
                      concept behind.<BR>
                      <BR>
                      For all the years Nikola Tesla made high voltage
                      coils, he always found that<BR>
                      quarter wave length wires produced the best results
                      for him.<BR>
                      <BR>
                      To get the highest resonant rise of potential (highest
                      voltage,) it is<BR>
                      necessary for the impedance at the base of the coil,
                      where the secondary<BR>
                      meets the ground, to be zero.  The coil best
                      suited for a zero ground<BR>
                      impedance is the quarter wave coil since the voltage
                      node is at ground (zero<BR>
                      volts.)  From voltage node and upward is just
                      part of the wave, however.<BR>
                      There is also a wave portion equal to the upper wave,
                      from the ground down.<BR>
                      This downward wave portion is a mirror of the upward
                      wave portion.<BR>
                      <BR>
                      This is why Wardencliffe needed such an extensive
                      underground grounding<BR>
                      system.  Tesla needed to easily sink 50 million
                      volts of negative potential<BR>
                      into the ground and just as easily project 50 million
                      volts of positive<BR>
                      potential into the atmosphere.  He chose the
                      large flat spiral coils for his<BR>
                      primary and secondary coils.  His secondary coil
                      also connected to other<BR>
                      spirals, free of mutual inductance with the
                      primary/secondary transformer<BR>
                      stage.  The total wire length of all the spirals
                      above the secondary would<BR>
                      have been equal to one quarter of the wavelength had
                      he not had a top<BR>
                      capacitance.  That large tower added enough
                      capacitance to the secondary<BR>
                      circuit that Tesla was able to use an odd multiple of
                      the quarter wave<BR>
                      length instead.<BR>
                      <BR>
                      But regardless of the size of the coil or the amount
                      of power put into it,<BR>
                      it is essential that the point where the wave passes
                      from atmosphere to<BR>
                      ground equals zero volts.  Otherwise the system
                      is unbalanced and difficult<BR>
                      to bring into resonance.<BR>
                      <BR>
                      It's important to realize that the quarter wave
                      frequency is a general rule<BR>
                      for a secondary coil with no top capacitance (or very
                      little capacitance.)<BR>
                      As the top load is increased, the length of wire can
                      be reduced.  Tesla made<BR>
                      sure the top load was sufficient that the wire length
                      was an odd multiple of<BR>
                      the quarter wave length.  That is if you started
                      with a wire 300 feet long<BR>
                      in your Tesla coil.  The same frequency can also
                      be resonated on a wire 100<BR>
                      feet long with the correct extra capacitance on the
                      terminal.  In the 300<BR>
                      feet wire example, the wave is traveling not only the
                      300 feet through the<BR>
                      wire, but also 300 feet into the ground. 
                      Traveling the full distance of 600<BR>
                      feet, the wave has traveled half of a cycle.  It
                      then travels back up the<BR>
                      system to the top of the coil for a full 1200 feet of
                      distance for one full<BR>
                      cycle.  Thus the wire in the coil is just 1/4 the
                      total distance the wave<BR>
                      will travel (or an odd multiple thereof.)<BR>
                      <BR>
                      This is why a good ground is essential for operating a
                      Tesla coil connected<BR>
                      to ground.  You can also operate two identical
                      coils and use one to act as<BR>
                      the ground.  So if you had a 300 feet long
                      secondary coil and built an<BR>
                      identical coil to use in place of the ground
                      connection, the wave will<BR>
                      travel its full cycle without use of a ground. 
                      This is the theory behind a<BR>
                      bipolar coil.  The total wire length in a bipolar
                      coil is half the<BR>
                      wavelength and the primary is situated in the middle
                      of the secondary.  The<BR>
                      resonant frequency is calculated accordingly.<BR>
                      <BR>
                      In the bipolar coil it is easy to see why the voltage
                      needs to be zero at<BR>
                      the halfway point.  If one coil were longer than
                      the other, then the system<BR>
                      can not resonate.  The same holds true for a
                      grounded coil.  If the voltage<BR>
                      node is not exactly at ground, then the system will
                      not fully resonate.<BR>
                      <BR>
                      I hope this helps.<BR>
                      <BR>
                      Dave<BR>
                      <BR>
                      David Thomson<BR>
                      dave@... <mailto:dave@...><BR>
                      <BR>
                      </tt>

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