Loading ...
Sorry, an error occurred while loading the content.
 

OLTC question

Expand Messages
  • Chris Swinson
    I was looking here at the OLTC http://scopeboy.com/tesla/t3concept.html (theres a few but this one is simple to explain my problem) However, while building it
    Message 1 of 6 , Jan 3, 2010
      I was looking here at the OLTC http://scopeboy.com/tesla/t3concept.html
      (theres a few but this one is simple to explain my problem)

      However, while building it is no problem I have a couple of problems with
      the workings out there..

      On that small OLTC he uses 1.88uF, other higher power designs he uses up to
      30uF. It seems to run from anything from 100 to 1000 BPS so that would
      assume the IGBT is running at the BPS figure (not in the khz range).

      However, 1.88uF and 3uH primary is 67khz, which could match a secondary of
      also 67khz, however, the problem I have is that what about the mutual
      inductance from the secondary ? it would actually make the primary's
      effective inductance more like 150uH.. and 1.88uF with 150uH = 9.5khz. Even
      more so by the time he got to 30uH it would be more like 2khz.

      his secondary coil calcs do not seem to tally good either. about 120khz is
      10" dia and 30" long using 0.4mm wire. JavaTC states 130uH effective primary
      inductance, so even with 1uF tank cap its only 12khz.

      As he talks about notches it seems it *is* in tune, but I cant see how it
      can be ?! I did wonder if it was just a single discharge pulse, but it is
      not clear, in particular when he states 100uF discharge time and talks about
      3rd notch quench, which suggests it is in tune, but it can't be.... ?

      He has 200mH and 1.4uF which would give 300hz resonance for the DC charging,
      so it should trigger the IGBT at 300BPS. no problems there.

      his later spec http://scopeboy.com/tesla/t4spec.html up to 30uF.. but
      again, just can't be used for resonance with the secondary, so a big "huh"
      is on my mind ?

      Chris
    • Bert Hickman
      Hi Chris, ... Yes. ... Mutual inductance is NOT a tuning issue. The mutual inductance is only a measure of the degree of coupling between the primary and
      Message 2 of 6 , Jan 3, 2010
        Hi Chris,

        Chris Swinson wrote:
        >
        >
        > I was looking here at the OLTC http://scopeboy.com/tesla/t3concept.html
        > <http://scopeboy.com/tesla/t3concept.html>
        > (theres a few but this one is simple to explain my problem)
        >
        > However, while building it is no problem I have a couple of problems with
        > the workings out there..
        >
        > On that small OLTC he uses 1.88uF, other higher power designs he uses up to
        > 30uF. It seems to run from anything from 100 to 1000 BPS so that would
        > assume the IGBT is running at the BPS figure (not in the khz range).

        Yes.

        >
        > However, 1.88uF and 3uH primary is 67khz, which could match a secondary of
        > also 67khz, however, the problem I have is that what about the mutual
        > inductance from the secondary ?

        Mutual inductance is NOT a tuning issue. The mutual inductance is only a
        measure of the degree of coupling between the primary and secondary
        systems. Primary and Secondary systems should be tuned independently
        without any effective coupling between the systems. The resonant
        frequency of the primary is tuned to the desired frequency using ONLY
        the primary tank cap and primary inductance - there should be no
        secondary present. Similarly, the secondary is tuned to the same desired
        frequency, with the primary inductor disconnected from the primary tank
        cap and the primary connected to ground. By setting these to be the
        same, they will be in "instrument: tune. Tweaking may be necessary to
        allow (i.e., lowering the primary frequency a bit) to account for spark
        loading.

        > It would actually make the primary's
        > effective inductance more like 150uH.. and 1.88uF with 150uH = 9.5khz. Even
        > more so by the time he got to 30uH it would be more like 2khz.
        >
        > his secondary coil calcs do not seem to tally good either. about 120khz is
        > 10" dia and 30" long using 0.4mm wire. JavaTC states 130uH effective
        > primary
        > inductance, so even with 1uF tank cap its only 12khz.
        >
        > As he talks about notches it seems it *is* in tune, but I cant see how it
        > can be ?! I did wonder if it was just a single discharge pulse, but it is
        > not clear, in particular when he states 100uF discharge time and talks
        > about
        > 3rd notch quench, which suggests it is in tune, but it can't be.... ?
        >
        > He has 200mH and 1.4uF which would give 300hz resonance for the DC
        > charging,
        > so it should trigger the IGBT at 300BPS. no problems there.
        >
        > his later spec http://scopeboy.com/tesla/t4spec.html
        > <http://scopeboy.com/tesla/t4spec.html> up to 30uF.. but
        > again, just can't be used for resonance with the secondary, so a big "huh"
        > is on my mind ?

        The big "Huh" should go away once you begin ignoring mutual inductances
        in tuning/resonant frequency calculations... use only the primary
        inductance and tank cap. JavaTC and FANTC will provide you with very
        good estimates based on the parameters of your planned system. While
        these programs will also provide you with mutual inductances, these are
        of no value for tuning purposes. Of more importance is the coupling
        factor "k" - you should shoot for something in the range of 0.12 - 0.18
        for good performance.

        >
        > Chris
        >

        Bert
        --
        *** /\ ******************************************************
        __ _\/_ __ * * * * * * * * *
        \_\/_/\_\/_/ We specialize in UNIQUE items! Coins shrunk using
        /\_\/_/\ ultra-strong magnetic fields, Captured Lightning
        _\/_/\_\/_ (Lichtenberg Figures), & technical Books. Please
        /_/\_\/_/\_\ come visit us at http://www.capturedlightning.com
        /\ * * * * * * * * *
        *** \/ ******************************************************
      • Chris Swinson
        Hi Bert, Right I see now! I always thought it was a factor, but things make more sense now! I was sure ( at least it was a couple of years ago) that the
        Message 3 of 6 , Jan 3, 2010
          Hi Bert,

          Right I see now! I always thought it was a factor, but things make more
          sense now!

          I was sure ( at least it was a couple of years ago) that the primary had
          some effect on the secondary, such as limiting its Q factor or something
          along those lines ? I know I talked a old chap who used to work on radar's
          for the RAF, clever chap, though while talking to him, he seemed to think
          that very loose coupling in the order of 0.05K or less would give a higher Q
          factor and higher voltage gain being "free" from the inductive effects from
          the primary, or at least something along those lines, never understood that
          much either!

          thanks!
          Chris



          ----- Original Message -----
          From: "Bert Hickman" <bert.hickman@...>
          To: <usa-tesla@yahoogroups.com>
          Sent: Sunday, January 03, 2010 7:10 PM
          Subject: Re: [usa-tesla] OLTC question


          > Hi Chris,
          >
          > Chris Swinson wrote:
          >>
          >>
          >> I was looking here at the OLTC http://scopeboy.com/tesla/t3concept.html
          >> <http://scopeboy.com/tesla/t3concept.html>
          >> (theres a few but this one is simple to explain my problem)
          >>
          >> However, while building it is no problem I have a couple of problems with
          >> the workings out there..
          >>
          >> On that small OLTC he uses 1.88uF, other higher power designs he uses up
          >> to
          >> 30uF. It seems to run from anything from 100 to 1000 BPS so that would
          >> assume the IGBT is running at the BPS figure (not in the khz range).
          >
          > Yes.
          >
          >>
          >> However, 1.88uF and 3uH primary is 67khz, which could match a secondary
          >> of
          >> also 67khz, however, the problem I have is that what about the mutual
          >> inductance from the secondary ?
          >
          > Mutual inductance is NOT a tuning issue. The mutual inductance is only a
          > measure of the degree of coupling between the primary and secondary
          > systems. Primary and Secondary systems should be tuned independently
          > without any effective coupling between the systems. The resonant
          > frequency of the primary is tuned to the desired frequency using ONLY
          > the primary tank cap and primary inductance - there should be no
          > secondary present. Similarly, the secondary is tuned to the same desired
          > frequency, with the primary inductor disconnected from the primary tank
          > cap and the primary connected to ground. By setting these to be the
          > same, they will be in "instrument: tune. Tweaking may be necessary to
          > allow (i.e., lowering the primary frequency a bit) to account for spark
          > loading.
          >
          >> It would actually make the primary's
          >> effective inductance more like 150uH.. and 1.88uF with 150uH = 9.5khz.
          >> Even
          >> more so by the time he got to 30uH it would be more like 2khz.
          >>
          >> his secondary coil calcs do not seem to tally good either. about 120khz
          >> is
          >> 10" dia and 30" long using 0.4mm wire. JavaTC states 130uH effective
          >> primary
          >> inductance, so even with 1uF tank cap its only 12khz.
          >>
          >> As he talks about notches it seems it *is* in tune, but I cant see how it
          >> can be ?! I did wonder if it was just a single discharge pulse, but it is
          >> not clear, in particular when he states 100uF discharge time and talks
          >> about
          >> 3rd notch quench, which suggests it is in tune, but it can't be.... ?
          >>
          >> He has 200mH and 1.4uF which would give 300hz resonance for the DC
          >> charging,
          >> so it should trigger the IGBT at 300BPS. no problems there.
          >>
          >> his later spec http://scopeboy.com/tesla/t4spec.html
          >> <http://scopeboy.com/tesla/t4spec.html> up to 30uF.. but
          >> again, just can't be used for resonance with the secondary, so a big
          >> "huh"
          >> is on my mind ?
          >
          > The big "Huh" should go away once you begin ignoring mutual inductances
          > in tuning/resonant frequency calculations... use only the primary
          > inductance and tank cap. JavaTC and FANTC will provide you with very
          > good estimates based on the parameters of your planned system. While
          > these programs will also provide you with mutual inductances, these are
          > of no value for tuning purposes. Of more importance is the coupling
          > factor "k" - you should shoot for something in the range of 0.12 - 0.18
          > for good performance.
          >
          >>
          >> Chris
          >>
          >
          > Bert
          > --
          > *** /\ ******************************************************
          > __ _\/_ __ * * * * * * * * *
          > \_\/_/\_\/_/ We specialize in UNIQUE items! Coins shrunk using
          > /\_\/_/\ ultra-strong magnetic fields, Captured Lightning
          > _\/_/\_\/_ (Lichtenberg Figures), & technical Books. Please
          > /_/\_\/_/\_\ come visit us at http://www.capturedlightning.com
          > /\ * * * * * * * * *
          > *** \/ ******************************************************
          >
          >
          > ------------------------------------
          >
          > Yahoo! Groups Links
          >
          >
          >


          --------------------------------------------------------------------------------



          No virus found in this incoming message.
          Checked by AVG - www.avg.com
          Version: 8.5.431 / Virus Database: 270.14.124/2597 - Release Date: 01/02/10
          08:22:00
        • Bert Hickman
          Hi Chris, Once the primary and secondary tuned circuits become coupled, all sorts of complex interactions begin to occur. Your friend was indeed correct - the
          Message 4 of 6 , Jan 3, 2010
            Hi Chris,

            Once the primary and secondary tuned circuits become coupled, all sorts
            of complex interactions begin to occur. Your friend was indeed correct -
            the tighter the coupling the greater the interaction between the primary
            and secondary circuits, and the greater the effect the low Q primary has
            on the high Q secondary. These interactions also impact the bandwidth of
            the combined system, the resulting primary and secondary Q's, the rate
            of energy transfer between the primary and secondary, and the formation
            of two frequency peaks (one above and one below the uncoupled resonant
            frequency) during high coupling. Some of these behaviors are discussed
            in Richie Burnett's excellent site. For example in the section about
            quenching, you can see the effect that various coupling coefficients
            have on frequency splitting:

            http://www.richieburnett.co.uk/operatn2.html#quenching

            Another very in-depth review of coupled tuned circuits is contained in
            chapter 3 of Frederick Terman's 1019 page book, "Radio Engineer's
            Handbook", 1943, McGraw-Hill. Although long out of print, used copies
            can easily be found for under $10. It should be on the shelf of every
            serious Tesla Coil researcher.

            See: http://used.addall.com/ or http://www.biblio.com/usedbooksearch.bib
            to locate a copy of your own.

            Bert
            --
            *** /\ ******************************************************
            __ _\/_ __ * * * * * * * * *
            \_\/_/\_\/_/ We specialize in UNIQUE items! Coins shrunk using
            /\_\/_/\ ultra-strong magnetic fields, Captured Lightning
            _\/_/\_\/_ (Lichtenberg Figures), & technical Books. Please
            /_/\_\/_/\_\ come visit us at http://www.capturedlightning.com
            /\ * * * * * * * * *
            *** \/ ******************************************************
            Chris Swinson wrote:
            >
            >
            > Hi Bert,
            >
            > Right I see now! I always thought it was a factor, but things make more
            > sense now!
            >
            > I was sure ( at least it was a couple of years ago) that the primary had
            > some effect on the secondary, such as limiting its Q factor or something
            > along those lines ? I know I talked a old chap who used to work on radar's
            > for the RAF, clever chap, though while talking to him, he seemed to think
            > that very loose coupling in the order of 0.05K or less would give a
            > higher Q factor and higher voltage gain being "free" from the inductive effects
            > from the primary, or at least something along those lines, never understood
            > that much either!
            >
            > thanks!
            > Chris
            >
            > ----- Original Message -----
            > From: "Bert Hickman" <bert.hickman@...
            > <mailto:bert.hickman%40aquila.net>>
            > To: <usa-tesla@yahoogroups.com <mailto:usa-tesla%40yahoogroups.com>>
            > Sent: Sunday, January 03, 2010 7:10 PM
            > Subject: Re: [usa-tesla] OLTC question
            >
            > > Hi Chris,
            > >
            > > Chris Swinson wrote:
            > >>
            > >>
            > >> I was looking here at the OLTC
            > http://scopeboy.com/tesla/t3concept.html
            > <http://scopeboy.com/tesla/t3concept.html>
            > >> <http://scopeboy.com/tesla/t3concept.html
            > <http://scopeboy.com/tesla/t3concept.html>>
            > >> (theres a few but this one is simple to explain my problem)
            > >>
            > >> However, while building it is no problem I have a couple of problems
            > with
            > >> the workings out there..
            > >>
            > >> On that small OLTC he uses 1.88uF, other higher power designs he
            > uses up
            > >> to
            > >> 30uF. It seems to run from anything from 100 to 1000 BPS so that would
            > >> assume the IGBT is running at the BPS figure (not in the khz range).
            > >
            > > Yes.
            > >
            > >>
            > >> However, 1.88uF and 3uH primary is 67khz, which could match a secondary
            > >> of
            > >> also 67khz, however, the problem I have is that what about the mutual
            > >> inductance from the secondary ?
            > >
            > > Mutual inductance is NOT a tuning issue. The mutual inductance is only a
            > > measure of the degree of coupling between the primary and secondary
            > > systems. Primary and Secondary systems should be tuned independently
            > > without any effective coupling between the systems. The resonant
            > > frequency of the primary is tuned to the desired frequency using ONLY
            > > the primary tank cap and primary inductance - there should be no
            > > secondary present. Similarly, the secondary is tuned to the same desired
            > > frequency, with the primary inductor disconnected from the primary tank
            > > cap and the primary connected to ground. By setting these to be the
            > > same, they will be in "instrument: tune. Tweaking may be necessary to
            > > allow (i.e., lowering the primary frequency a bit) to account for spark
            > > loading.
            > >
            > >> It would actually make the primary's
            > >> effective inductance more like 150uH.. and 1.88uF with 150uH = 9.5khz.
            > >> Even
            > >> more so by the time he got to 30uH it would be more like 2khz.
            > >>
            > >> his secondary coil calcs do not seem to tally good either. about 120khz
            > >> is
            > >> 10" dia and 30" long using 0.4mm wire. JavaTC states 130uH effective
            > >> primary
            > >> inductance, so even with 1uF tank cap its only 12khz.
            > >>
            > >> As he talks about notches it seems it *is* in tune, but I cant see
            > how it
            > >> can be ?! I did wonder if it was just a single discharge pulse, but
            > it is
            > >> not clear, in particular when he states 100uF discharge time and talks
            > >> about
            > >> 3rd notch quench, which suggests it is in tune, but it can't be.... ?
            > >>
            > >> He has 200mH and 1.4uF which would give 300hz resonance for the DC
            > >> charging,
            > >> so it should trigger the IGBT at 300BPS. no problems there.
            > >>
            > >> his later spec http://scopeboy.com/tesla/t4spec.html
            > <http://scopeboy.com/tesla/t4spec.html>
            > >> <http://scopeboy.com/tesla/t4spec.html
            > <http://scopeboy.com/tesla/t4spec.html>> up to 30uF.. but
            > >> again, just can't be used for resonance with the secondary, so a big
            > >> "huh"
            > >> is on my mind ?
            > >
            > > The big "Huh" should go away once you begin ignoring mutual inductances
            > > in tuning/resonant frequency calculations... use only the primary
            > > inductance and tank cap. JavaTC and FANTC will provide you with very
            > > good estimates based on the parameters of your planned system. While
            > > these programs will also provide you with mutual inductances, these are
            > > of no value for tuning purposes. Of more importance is the coupling
            > > factor "k" - you should shoot for something in the range of 0.12 - 0.18
            > > for good performance.
            > >
            > >>
            > >> Chris
            > >>
            > >
            > > Bert
            > > --
            > > *** /\ ******************************************************
            > > __ _\/_ __ * * * * * * * * *
            > > \_\/_/\_\/_/ We specialize in UNIQUE items! Coins shrunk using
            > > /\_\/_/\ ultra-strong magnetic fields, Captured Lightning
            > > _\/_/\_\/_ (Lichtenberg Figures), & technical Books. Please
            > > /_/\_\/_/\_\ come visit us at http://www.capturedlightning.com
            > <http://www.capturedlightning.com>
            > > /\ * * * * * * * * *
            > > *** \/ ******************************************************
          • Chris Swinson
            Hi Bert, I did read Richie s site a few times, be it a while back, during my more classic TC days! I will keep an eye out for the book, I actually like the
            Message 5 of 6 , Jan 3, 2010
              Hi Bert,

              I did read Richie's site a few times, be it a while back, during my more
              classic TC days! I will keep an eye out for the book, I actually like the
              older ones as they always seemed to explain it in ways which made sense.

              It would seem better to use a lower coupling to gain a higher secondary Q,
              but may not exactly be that easy.

              Though one other thing I still don't fully understand is the energy transfer
              between primary and secondary. For example, if you place 2 coils side by
              side and run one from 12volts and use a low coupling, the other coil will
              only see about 1volt if you are lucky. If it was a CW then that 1V would be
              in resonance with the coil and build up voltage. Though I do not see the
              entire primary energy actually being transferred to the secondary. Though
              with that idea, it would be better to use closer coupling. Can't really have
              it both ways!

              Though the way its explained is if you have X amount of energy and 0.10K
              then you could assume maybe it will take 10cycles to transfer the energy
              from primary to secondary. But how can the energy not simply be lost over
              the distance between primary and secondary ? In general I just accept what
              is told is true, but I must confess I still don't follow it!

              The way I look at it, if you had 10Joules and 0.10K and it took 10 cycles,
              then to me that would mean each cycle would be 1Joule (putting it simply),
              but would actually loose 90% of that energy due to low coupling. So on that
              note, the secondary would see 0.1J for 10 cycles.

              Probably not that simple since the capacitor discharges its energy will get
              less per cycle, or at least I assume so. Though I hope I explained the
              "problem" enough for you to follow.

              Chris




              ----- Original Message -----
              From: "Bert Hickman" <bert.hickman@...>
              To: <usa-tesla@yahoogroups.com>
              Sent: Sunday, January 03, 2010 9:47 PM
              Subject: Re: [usa-tesla] OLTC question


              > Hi Chris,
              >
              > Once the primary and secondary tuned circuits become coupled, all sorts
              > of complex interactions begin to occur. Your friend was indeed correct -
              > the tighter the coupling the greater the interaction between the primary
              > and secondary circuits, and the greater the effect the low Q primary has
              > on the high Q secondary. These interactions also impact the bandwidth of
              > the combined system, the resulting primary and secondary Q's, the rate
              > of energy transfer between the primary and secondary, and the formation
              > of two frequency peaks (one above and one below the uncoupled resonant
              > frequency) during high coupling. Some of these behaviors are discussed
              > in Richie Burnett's excellent site. For example in the section about
              > quenching, you can see the effect that various coupling coefficients
              > have on frequency splitting:
              >
              > http://www.richieburnett.co.uk/operatn2.html#quenching
              >
              > Another very in-depth review of coupled tuned circuits is contained in
              > chapter 3 of Frederick Terman's 1019 page book, "Radio Engineer's
              > Handbook", 1943, McGraw-Hill. Although long out of print, used copies
              > can easily be found for under $10. It should be on the shelf of every
              > serious Tesla Coil researcher.
              >
              > See: http://used.addall.com/ or http://www.biblio.com/usedbooksearch.bib
              > to locate a copy of your own.
              >
              > Bert
              > --
            • Bert Hickman
              Hi Chris, ... You re right - it s not trivial. There s a balance between too low a k (and getting excessive primary energy loss from primary resistance and
              Message 6 of 6 , Jan 3, 2010
                Hi Chris,

                Chris Swinson wrote:
                >
                >
                > Hi Bert,
                >
                > I did read Richie's site a few times, be it a while back, during my more
                > classic TC days! I will keep an eye out for the book, I actually like the
                > older ones as they always seemed to explain it in ways which made sense.
                >
                > It would seem better to use a lower coupling to gain a higher secondary Q,
                > but may not exactly be that easy.

                You're right - it's not trivial. There's a balance between too low a k
                (and getting excessive primary energy loss from primary resistance and
                switching losses) and too high a "k" (exceeding the rate of energy
                growth into the secondary, causing racing sparks or failure to quench in
                a SGTC). Best performance usually occurs for "k" in a range of 0.12 -
                0.18 for spark gap coils. This also seems to be a good range for high
                power SSTC's, DRSSTC's and OLTC's. For a variety of reasons, VTTC's
                perform best with a "k" of about 0.15 - 0.30 since energy growth is
                already limited by the peak power available from the vacuum tube oscillator.

                >
                > Though one other thing I still don't fully understand is the energy
                > transfer
                > between primary and secondary. For example, if you place 2 coils side by
                > side and run one from 12volts and use a low coupling, the other coil will
                > only see about 1volt if you are lucky. If it was a CW then that 1V would be
                > in resonance with the coil and build up voltage. Though I do not see the
                > entire primary energy actually being transferred to the secondary. Though
                > with that idea, it would be better to use closer coupling. Can't really
                > have
                > it both ways!

                Operation is different for pulsed coils versus CW coils. Pulsed coils
                depend on the "transient response" of the coupled tuned circuits, while
                CW coils depend on both the transient and the "steady state" response of
                the system. In a SGTC or OLTC, we have a fixed amount of initial energy
                (the bang size) stored in the tank capacitor. This is ALL we have to
                work with each time the primary switch closes (spark gap or switching
                transistor is turned ON). Once we begin transferring energy, we also
                begin losing a fraction of this energy to resistive losses and to the
                switch. If we have a low "k", the energy transfer will take more time,
                and we'll lose more energy before the transfer is complete.

                Ideally, we'd like to transfer the energy very quickly (i.e., high "k")
                but if the secondary can't absorb this energy quickly enough, it will
                cause racing sparks on the secondary. This tends to limit maximum "k".
                As you lower "k", more energy is lost before the transfer is complete,
                and maximum amount of energy making it to the secondary declines. The
                best "k" for a system is usually found experimentally.

                >
                > Though the way its explained is if you have X amount of energy and 0.10K
                > then you could assume maybe it will take 10cycles to transfer the energy
                > from primary to secondary. But how can the energy not simply be lost over
                > the distance between primary and secondary ? In general I just accept what
                > is told is true, but I must confess I still don't follow it!

                There is a direct relationship between "k" and the number of cycles it
                takes to fully transfer energy from P--->S or S---->P. For k=0.1, this
                is about 10 half-cycles or 5 cycles. Let's assume you removed primary
                and secondary resistive and switching losses. In this case, 100% of the
                energy would transfer from P--->S over a number of cycles, and then
                would transfer from S---->P over over the same number of cycles. Energy
                would continue to transfer between the primary and secondary
                indefinitely... as long as "k" is greater than zero.

                Since real world Tesla coil primary and secondary circuits have losses,
                the system energy continually declines as it transfers back and forth,
                eventually declining to zero. By balancing losses, quenching, and "k", a
                well designed SGTC can transfer over 85% of the initial bang energy to
                the secondary over even though the "k" may only be 0.12 - 0.18. For k =
                0.18, it will take about 3 RF cycles to completely transfer energy from
                P to S or vice-versa.

                >
                > The way I look at it, if you had 10Joules and 0.10K and it took 10 cycles,
                > then to me that would mean each cycle would be 1Joule (putting it simply),
                > but would actually loose 90% of that energy due to low coupling. So on that
                > note, the secondary would see 0.1J for 10 cycles.

                You're looking at it incorrectly. There are no losses directly
                attributable to "k". However, having lower "k" DOES require a longer
                time (more RF cycles) to transfer energy between P and S (or vice
                versa). As k decreases, more system energy will be lost through
                resistive losses leaving less energy left at the end of the transfer.
                You may wish to revisit Richie's site again with the above explanations
                in mind...
                >
                > Probably not that simple since the capacitor discharges its energy will get
                > less per cycle, or at least I assume so. Though I hope I explained the
                > "problem" enough for you to follow.

                Hope the above helps..

                Bert
                >
                > Chris
                >
                > ----- Original Message -----
                > From: "Bert Hickman" <bert.hickman@...
                > <mailto:bert.hickman%40aquila.net>>
                > To: <usa-tesla@yahoogroups.com <mailto:usa-tesla%40yahoogroups.com>>
                > Sent: Sunday, January 03, 2010 9:47 PM
                > Subject: Re: [usa-tesla] OLTC question
                >
                > > Hi Chris,
                > >
                > > Once the primary and secondary tuned circuits become coupled, all sorts
                > > of complex interactions begin to occur. Your friend was indeed correct -
                > > the tighter the coupling the greater the interaction between the primary
                > > and secondary circuits, and the greater the effect the low Q primary has
                > > on the high Q secondary. These interactions also impact the bandwidth of
                > > the combined system, the resulting primary and secondary Q's, the rate
                > > of energy transfer between the primary and secondary, and the formation
                > > of two frequency peaks (one above and one below the uncoupled resonant
                > > frequency) during high coupling. Some of these behaviors are discussed
                > > in Richie Burnett's excellent site. For example in the section about
                > > quenching, you can see the effect that various coupling coefficients
                > > have on frequency splitting:
                > >
                > > http://www.richieburnett.co.uk/operatn2.html#quenching
                > <http://www.richieburnett.co.uk/operatn2.html#quenching>
                > >
                > > Another very in-depth review of coupled tuned circuits is contained in
                > > chapter 3 of Frederick Terman's 1019 page book, "Radio Engineer's
                > > Handbook", 1943, McGraw-Hill. Although long out of print, used copies
                > > can easily be found for under $10. It should be on the shelf of every
                > > serious Tesla Coil researcher.
                > >
                > > See: http://used.addall.com/ <http://used.addall.com/> or
                > http://www.biblio.com/usedbooksearch.bib
                > <http://www.biblio.com/usedbooksearch.bib>
                > > to locate a copy of your own.
                > >
                > > Bert
                > > --
                >
                >
              Your message has been successfully submitted and would be delivered to recipients shortly.