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Author Topic: parametric pumping of L's and C's  (Read 36938 times)
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I think what we are missing here is that it takes some mechanical work to vary the inductance of an L in an LC oscillating circuit.
...

I agree with you. This is a bias of all parametric operations: changing the parameter requires at least as much energy as the energy that will be recovered by the system.
The typical example is the capacitor. To increase its energy E=Q²/2.C, one decreases C by moving the plates apart from each other, so one exerts a force against the Coulomb force that attracts the two plates, and it is easy to calculate that this mechanical energy is exactly what one will gain in the capacitor in electrical form.
The advantage of a parametric device is only if the parameter can be varied free of charge, for example thanks to the ambient heat.



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Hi F6FLT,

I certainly agree with you in the case of mechanical change in capacitance. I also agree with you that using parametric change for energy harvesting is very promising. I've often toyed with the idea of using a solar panel as a varicap to tap energy from heat changes at night.

What I find a bit difficult to understand is why nobody has done a similar power balance for any other type of parameter change? I find no examples in the literature that treat the solid-state variable capacitor situation. I've found exactly one paper that talks about variable inductors, and it's not a good paper. All others simply refer back to your example. I've looked hard.
Extremely dissimilar physical situations, for instance a hyperabrupt varactor diode, are treated as identical, and the discussion is ended.
The varactor diode we used in our tests, BB212, had a capacitance variation of 29-- that is, the C was reduced from about 550 pF to about 18 pF --with an application of 10 V reverse bias. The reverse current at full bias is 50-300 nA, depending on temperature. Taking an average value at room temp of 175 nA, the power input to change the varactor C by this huge amount is obviously 1750 nW. Since the device easily operates at 1 Mhz, we can say that the C change takes 10-6 second (actually it can be much faster) so the work that the reverse bias source did to change the C, assuming the V is applied instantaneously and held for the entire 10-6 second) is .00175 nJ. Let's say the varactor was already charged to 2 V at the start of this process, giving a beginning energy of 1/2CV^2 = 1100 pJ. Now at the end of this process, with V at approx. 58 V, the energy stored in the capacitor is 42050 pJ, with a net energy gain of 40950 pJ. Regularizing units, the energy input to change the C is 1.75 pJ. So, the energy needed to change the C is apparently not similar to the energy now stored in the varactor.
Because parametric oscillators and amplifiers typically use a C ratio of around 2.5, and the above diode is used for tuning AM radios, there is little in the literature about the behavior of these hyperabrupt diodes in a parametric oscillator. But we saw some pretty strong energy gains in a device we built. Being naive, we attempted to get a self runner before we had done some serious power balance, so the situation is still up in the air. I'll post the patent that was based on when I find it again.

Regards,
Fred

 
   
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Hi F6FLT,

I certainly agree with you in the case of mechanical change in capacitance. I also agree with you that using parametric change for energy harvesting is very promising. I've often toyed with the idea of using a solar panel as a varicap to tap energy from heat changes at night.

What I find a bit difficult to understand is why nobody has done a similar power balance for any other type of parameter change? I find no examples in the literature that treat the solid-state variable capacitor situation. I've found exactly one paper that talks about variable inductors, and it's not a good paper. All others simply refer back to your example. I've looked hard.
Extremely dissimilar physical situations, for instance a hyperabrupt varactor diode, are treated as identical, and the discussion is ended.
The varactor diode we used in our tests, BB212, had a capacitance variation of 29-- that is, the C was reduced from about 550 pF to about 18 pF --with an application of 10 V reverse bias. The reverse current at full bias is 50-300 nA, depending on temperature. Taking an average value at room temp of 175 nA, the power input to change the varactor C by this huge amount is obviously 1750 nW. Since the device easily operates at 1 Mhz, we can say that the C change takes 10-6 second (actually it can be much faster) so the work that the reverse bias source did to change the C, assuming the V is applied instantaneously and held for the entire 10-6 second) is .00175 nJ. Let's say the varactor was already charged to 2 V at the start of this process, giving a beginning energy of 1/2CV^2 = 1100 pJ. Now at the end of this process, with V at approx. 58 V, the energy stored in the capacitor is 42050 pJ, with a net energy gain of 40950 pJ. Regularizing units, the energy input to change the C is 1.75 pJ. So, the energy needed to change the C is apparently not similar to the energy now stored in the varactor.
Because parametric oscillators and amplifiers typically use a C ratio of around 2.5, and the above diode is used for tuning AM radios, there is little in the literature about the behavior of these hyperabrupt diodes in a parametric oscillator. But we saw some pretty strong energy gains in a device we built. Being naive, we attempted to get a self runner before we had done some serious power balance, so the situation is still up in the air. I'll post the patent that was based on when I find it again.

Regards,
Fred

Hi Fred,

Some here are perhaps not aware of the rather large positive parametric capacitance change in solar cells so here is an sim example for a Solar Africa SA-25M panel.  Data was taken from the panel for light intensities up to 1 Sun and the resulting plot was used to generate the polynomial equation for Q.

The sim uses a switched constant current source of 100ma with the resulting voltage change seen in the pink trace which then is used to calculate the capacitance change over 100us as seen in the red trace.  The two cursor samples show 49.6nF and 365.4nF respectively.

This large value and change should be able to be tapped for improved PV performance as we had discussed years ago because normally most PV applications are used in DC modes AFAIK.

Regards,
Pm
   
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Hi Partzman,

Yes, this still seems like a really good area for experiments! Yes, PV is all DC, except for an outlier patent that uses the negative resistance above MPPT to superimpose AC on the cell output.

That patent from Dahlberg I posted in the thermoelectric threads shows arrangements where a solar panel could be switched or dioded to be part of a resonant circuit. With a fixed inductor, the natural frequency will vary with C changes (leading to some tricky switching!). Additional voltage can be put across the panel when the C starts dropping, and extracted just as the C starts to rise. The solar panel DC output is added to the wave, of course. At first glance, the loss reduction from reduction in I that Dahlberg talks about would also still exist. (He shows that the output of his panel using his technique is approximately equal to Voc * Iss-- that is, well above the MPPT output).

I think, given the previous discussions, that we would use added voltage to get the parametric gain, rather than trying to use the solar output itself. I note that modern panels, like the ones from Sunpower, have a much higher baseline C than the older cells, so a lot more energy could be stored in the panel at peak C.

There are a lot of patents and concepts floating around for energy harvesters using parametric changes. But most use relatively exotic materials like ferroelectrics.  But here we already have a vast network of potential parametric amplifiers, already installed!

Regards,
Fred
   
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It's turtles all the way down
Also check out Vasik's entry here:

https://www.overunityresearch.com/index.php?topic=3688.msg70605#msg70605

 about the work of Hans Weber and the follow on posts in that thread.


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Hi Fred,

Applying Dalhberg's technique to the SA-25M would result in an output gain of ~ 133%!  This needs to be looked into considering the installed PV base worldwide!

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Hi Partzman,

Yes, the Dahlberg patent would revolutionize the energy situation if it were adopted. It's common sense that once the pv cells are part of an oscillating circuit, their voltages and currents can be controlled for minimum thermal losses. It's not parametric per se, but to my mind another example of making the energy flow slow, relative to the time constant of the system, as in adiabatic charging of a capacitor. As I think you know, I always thought that ALL the energy in the solar cell could be transferred through a CLC resonant transfer circuit without any thermal losses at all! 

I also have a couple other solar cell ideas bubbling around.  Maybe our beloved moderator can start a Light to Electricity forum, parallel to the Heat to Electricity one? Thanks!

Fred

   
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Hi folks,

Here is the patent I was trying to find that Roberto Notte and I checked out. On overunity.com he shows a photo of his circuit and says:

"I did in the past experimentation on parametric amplification following the most significative available patents. All started with a successful replication of the basic JLN implementation as per:  http://jnaudin.free.fr/html/paramp31.htm

I've to say that circuits built do work as described by patents (pat 3,125,725 Frequency converter -Chang, pat US20080185916 F Corum Power multiplication, Parametric conversion with varactors -Chan et all, etc). Mainly I used parallel of 4 varactors (Sanyo SVC389) in order to change periodically their capacitance via an external oscillator hence pumping main tank resonation to 2x or 4x.

Most interesting has been my version of E.B. Gunn push-pull circuit that delivered something very near to a self runner.
True self-runner anyway has been proved impossible at least with my resources. "

The interesting thing about our replication of the Gunn patent is that we didn't follow it completely, and still got some decent results.

 Gunn intends for two closely associated tank circuits to be tuned to, for instance,  5 and 8 Mhz. The lower tank has varactors in it. After some oscillations have started in this tank, a step voltage that takes several cycles biases the varactor, and the C drops. The oscillation increases in both power and frequency, and is now detuned from the lower tank and tuned to the higher one, so that all energy transfers there.
Gunn speaks of 'surges'. Gunn says because the dissipation in the system is low, that, as in quantum mechanics, the increasing frequency represents an increase in energy. But he also reports an increase in magnitude too-- all from a Dc bias of a couple of volts. So I thought it was worth checking out.
 
But we only made the first stage of the device without the second set of coils where the energy is transferred to. We saw it as a clever push pull design, but not the key part. We also didn't apply the energy over several cycles, as the patent specifies. And finally, we used a hyperabrupt diode (the SVC389, rather than the BB212 I mentioned earlier) rather than his old school diode, which probably had a C ratio of .5-1.5.

I suspect we got as good as we did, simply because of the extreme amplification in the diode, but not sure.. still it was not really the invention that Gunn laid out...

Regards,
Fred
   
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I think what we are missing here is that it takes some mechanical work to vary the inductance of an L in an LC oscillating circuit.



Good day All:

I haven't posted anything here on OUR forum in a few years, figured it was time for some input. :D

A few years ago, I was thinking about the options available to switch either the *L* or the *C* or possibly both in a parametric circuit.
After reading through about all the available literature (Google) at the time, I came across the idea of **Phase** switching using a micro-controller to facilitate the switching of the *C* reactance of the parametric circuit in order to increase/decrease *C* reactance as if mimicking the physical movement of capacitor plates.
I designed and built a singled-ended >> isolated complimentary driver the used the AVAGO ACPL-K33T opto-driver (500ns max switching freq) and the UCC3715 complimentary switch FET driver (forward converter && synchronous rectification apps) along with on board isolated power supplies that float a neg. voltage @ gate/drain for fast switch discharge/turn off.  Basically the pcb will input a single-ended signal and output an isolated complimentary drive signal w/ programmable DT.
Attached some photos of my pcb design and the populated pcb.  I actually designed the pcb for a 3.5Kw synchronous linear ramp buck converter, (https://www.youtube.com/watch?v=Wro3TAjViDc , https://www.youtube.com/watch?v=c1SrA6sz7Kk) but the application of the parametric phase switching of *C* or *L* reactance is essentially the same as synchronous rectification. 
I never had time to code the u_controller or build the actual Parametric circuit that I had envisioned, but I do have the pcbs made that could be used for part of this project.

take care, peace
lost_bro

EDIT: spelling error
« Last Edit: 2019-04-18, 20:49:20 by lost_bro »
   
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Hi Orthofield,

I'm just making a general answer on the subject of parametric systems (I don't have much time this week).
I think it's a right track. If overunity there may be somewhere, parametric systems are certainly to be tried. Why? Because energy can be transferred from one system to another in a subtle and often non-linear way, and the nature of the source energy can be very different from that of the destination. This could make it possible to tap into hidden sources, or known ones but difficult to access such as nuclear reactions.
I am not so optimistic when C or L are the parameters, because it can easily be shown that the energy required to change these parameters is exactly the one you gain electrically in the system. It's to be known nevertheless it's not a dead end, you can imagine, for example, LENRs or Maxwell's demons in these kinds of experiments, especially if there is a big power. I'm going to follow with interest what you're doing.



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Hi F6FLT,

Yes, I agree that there is some possibility of a Maxwell's demon type of effect, especially in experiments with switched inductors and capacitors that have consistently shown small voltages at harmonic frequencies, even with isolated switches. The paper by Barrow that I uploaded a while back is a very interesting experiment done in the 30s at MIT where the investigators naively assumed that switching a capacitor in and out of a tank would be the same as rotating a plate capacitor (in the later case of course output = input). Nonetheless they showed parametric oscillations at the appropriate harmonics, when the system was made lossless by using a regenerative circuit. There should have been nothing to amplify under the experimental conditions given. I found the paper because it was mentioned in a footnote in one of the Mandleshtam and Papaleksi papers, where they criticized it for violating C of E. It does seem to do so.

F.


   
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hi lost_bro,

Very interesting! I'd read the first paper by Horst before but not the second, more important one.

I have a lot of comments, to keep them short I will bullet point them:

1) The circuits which switch static caps or inductors in and out of the circuit are similar to the one Barrow tested in the 30s, and the one that JLN and I tested in the 90s. Barrow is uploaded earlier in this thread. Switching artifacts are important to avoid of course. The JLN tests were crude relay tests, but later I repeated the tests with another experimenter using opto-isolated hexfets and also saw voltage spikes in the switched cap circuit. They were nothing like a parametric oscillation, but isolated voltage spikes, in the mV range, that were on the parametric resonance frequencies-- like they were trying to be oscillations. Although these were small in amplitude, they should not have been there at all under the test conditions, and I can only think that noise voltages present in the wire of the circuit were being amplified by the switching of the caps.

2) Barrow talks at length about antiresonance in his circuit, when the capacitors are switched so that their internal voltage is opposed to that of the circuit. Of course if an L or C is switched in and out of a circuit, charge or flux will be lost-- however it would be possible to switch the components into another tank when taken out of the first one, and this appears to be the only way that these types of circuits could conceivably get any serious output. As in the Barrow circuit, the total R of the circuit would need to be extremely low to allow parametric oscillations to happen at all under these conditions where zero voltage switching is used. Overall, I think these switched circuits are of scientific interest but not likely to get a powerful device.

3) More immediately useful is the case of varactor diodes. As Horst notes, the real issue that enforces reciprocality in these circuits is that the rising voltage of the parametric oscillations also changes the C of the varactors. Horst does use the hyperabrupt diodes which I consider the best candidate, because of their extreme nonlinearity. After much looking, I did find a class of parametric amplifiers/oscillators where output V was somewhat isolated from the varactors. I consider the best of these the circuit by Gunn, uploaded earlier in this thread. In this circuit, two high Q tuned circuits at different frequencies are used. An oscillation is started in the first circuit, which contains a varactor or several, which are biased by a step or ramp voltage over several cycles of the oscillation. At the end of this period, the frequency and amplitude of the oscillation are increased, and the energy is now tuned to the second tank circuit, and essential jumps over to that circuit, where it can be used. Gunn speaks of 'surges' of energy. As you can see, the output voltage swings several times from highest to lowest during one cycle of varactor bias. Maybe this isolates the varactor to some extent, since the varactor supply will see equal amounts of voltage increase and reduction? His varactors were of the old school type, with (typically) a C ratio of less than 3. I consider this circuit to be a good point for further experimentation, since Roberto Notte and I almost got self running even with the output oscillations fully interacting with the varactors.

4) Switching can also be very relevant to standard parametric oscillators where the parameter change is done at quadrature. The paper from Howson and Szerlip, attached, shows that if the parameter changing element is switched into the circuit only at quadrature (more or less) then the power gain of such amplifiers can be made infinite (contrary to the Manley-Rowe relation where the gain is limited to F2/F1).  Pages 6 and on show the experimental work. This also may be a way of disconnecting the varactor (or other element) from the parametric output.

5) In inductive circuits, the parametric oscillation flux is such to create a loss in the drive power supply by raising the inductance when power supply current is at peak. Although the use of 'nullifying' output coils has been justifiable scotched as an OU mechanism in the case of inductive circuits, I still wonder about circuits where the output is created through parametric changes, and induction is cancelled by filtering. This is why I proposed an inductive circuit that uses two parametric oscillators in the output, whose fluxes are closely coupled and opposite. I can also vaguely see some ways that a varactor coupled with an inductor, as a unit, could be isolated in these ways...

6) I've collected a lot of parametric circuits, so I'm going to go back and really zero in on this issue of output voltage affecting the varactors, to see if somebody else has solved this problem. The word 'nonreciprocal' is often used with these devices, but I believe this refers to interaction between input and output signals, rather than the varactor itself. I still live in hope :-)

Fred
   
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This may be interesting in the context: https://phys.org/news/2019-04-newly-static-negative-capacitor.html

I downloaded the article from Nature but I haven't understood much yet.


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Regarding the Gunn patent, I actually had an LtSpice IV sim that did show a gain after the up conversion to the higher frequency tank circuit but unfortunately, this was lost in a past computer crash.  I have not taken the time to replicate this due to lack of patience but it did appear that there is something to Gunn's claims.

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HI F6FLT,

Not immediately useful (lack of ferroelectric nanoparticles in the immediate environment :-) though still interesting...

There are a lot of esoteric capacitors out there that might be used in a parametric OU device, in particular ones using a tube filled with ionizable gas, inserted between capacitor plates. I've seen several versions of this. There seems to be some indication that the energy needed to ionize the gas can be lower than the amplification caused by the C. There's a patent (forgot the inventor's name at the moment) that uses a sandwich of many tubes and many capacitor layers. The inventor claims antigravity effects along with radical changes in C.
I don't usually bring this up, because it does require some gas/plasma experience, but it just occurred to me that something like this could be done with small commercial neon indicator lamps, sandwiched between foil sheets.

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Hi Partzman,

Very interesting that your sim showed gainful behavior. Did your sim use one of the (hyperabrupt diodes? Did the sim show the transfer of energy to the higher frequency tank as Gunn describes?

I found his reference to 'energy of frequency' to be very interesting, because he is treating the oscillation as if it were a giant photon, where E = Hv would generally apply. I'm not aware of any other case where frequency mulltiplication, etc. is treated as an energy gain. In fact, in parametric terms, typically not much of the energy will go to the new frequency, since a lot is left at other sidebands. My guess is Gunn saw energy gain in his circuit, and wanted to preserve a scientific rationale that made sense to him.

In reviewing the work I did with Roberto on this the last few days, I was embarrassed (again) by my lack of electronics knowledge. I consistently misinterpreted some simple statements he made, and I completely missed, or forgot, the key aspect of the patent which might have made it overunity. I must have driven him crazy :-)

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Hi Partzman,

Very interesting that your sim showed gainful behavior. Did your sim use one of the (hyperabrupt diodes?

I don't recall but I'm sure I would have used a model that was available at the time in LtSpice.

Quote
Did the sim show the transfer of energy to the higher frequency tank as Gunn describes?

Yes, and this is where the gain manifested itself.  It took a great deal of circuit adjustment and tuning to achieve any gain however.

Quote
I found his reference to 'energy of frequency' to be very interesting, because he is treating the oscillation as if it were a giant photon, where E = Hv would generally apply. I'm not aware of any other case where frequency mulltiplication, etc. is treated as an energy gain. In fact, in parametric terms, typically not much of the energy will go to the new frequency, since a lot is left at other sidebands. My guess is Gunn saw energy gain in his circuit, and wanted to preserve a scientific rationale that made sense to him.

In reviewing the work I did with Roberto on this the last few days, I was embarrassed (again) by my lack of electronics knowledge. I consistently misinterpreted some simple statements he made, and I completely missed, or forgot, the key aspect of the patent which might have made it overunity. I must have driven him crazy :-)

F.

You probably don't remember but I showed the sim results to both you and Roberto at that time.  IIRC, I didn't "see" the gain in Roberto's bench circuit as he saw it.

Regards,
Pm
   
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Hi Partzman,

I found some mails from you about that simulation and I'm reading it now. Unfortunately, so far I haven't found the sims themselves, labelled "Gunn2" I believe.

This would be a very finicky circuit indeed, both sim and reality. The tuning and other issues would get even worse with the hyperabrupt diodes!
I see a spice model from 2015 that has varactors with a C ratio of about 15, so maybe you used something like that.

I wonder if there is some way to get rid of the two tanks? I've thought of a couple things, then knocked them down again.  It seems to be difficult to avoid them!

Quartz oscillators can be tuned by an associated capacitor, and they are also extremely stable, so there might be some way to build up oscillations in one of them, then transfer through a nonlinear reactance to another higher frequency qtz oscillator?? There is a New Age myth via Edgar Cayce and the like, that they can be a source of power :-)

F.



 
   
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The varactor diode we used in our tests, BB212, had a capacitance variation of 29-- that is, the C was reduced from about 550 pF to about 18 pF --with an application of 10 V reverse bias. The reverse current at full bias is 50-300 nA, depending on temperature. Taking an average value at room temp of 175 nA, the power input to change the varactor C by this huge amount is obviously 1750 nW
...

Hi Fred,

The reverse static current is not relevant, it is only a leakage current that does not participate in the parameter change.
The important current to know is the one drawn during the dynamic variation of the capacity. This corresponds to the work done to "move the capacitor plates away from each other", because even if we are dealing with a semiconductor, it is the equivalent of this operation that is performed.
The product of this current by the voltage, integrated on the changeover time of C, corresponds to the work that opposes that of the Coulomb force between plates F=q.E, it cannot be lower. So unless you have an idea to get this current from something other than the varicap control signal, there will be no gain.

...
Not immediately useful (lack of ferroelectric nanoparticles in the immediate environment :-) though still interesting...

There are a lot of esoteric capacitors out there that might be used in a parametric OU device

In this type of paper, the manufacturing recipe counts much less than the underlying principle. Even if we do not have ferroelectric nanoparticles, we may be able to get around the problem and apply it differently, for instance with electrets.
Certainly there are many ways to make a parametric change of a capacitor, but how to do it without it costing us more than we're going to earn, that's the one and only question.


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Diodes like 1N4007 and zener diodes can be used as varactors, they have quite big range

For example in this video test setup presented, capacitance change from 24pf to 2000pf

https://www.youtube.com/watch?v=zTKShnW4w-8

Regards,
Vasik


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Hi F6LT,

The reverse static current is not relevant, it is only a leakage current that does not participate in the parameter change.

Agreed. In fact it occurs to me that the varactors could be driven by a supply that has a much higher output impedance. It's the voltage that seems the bigger issue for me, since when the para oscillations start, the bias signal will be drowned out by the larger voltage. But if the supply puts out say 20 nA current at 50 V (like some version of a HV supply I've seen used for electrostatic precipitators) then the para oscillations can go much higher.

The important current to know is the one drawn during the dynamic variation of the capacity. This corresponds to the work done to "move the capacitor plates away from each other", because even if we are dealing with a semiconductor, it is the equivalent of this operation that is performed.

I admit that the situation I described is an artificial one (and not even accurate, as I look back on it). We saw current spikes into the varactor bias in dynamic operation. However, even with that we got self running for a short period of time, and the reason the device stopped had more to do with matching impedances than with a lack of energy to drive it. I think the static or quasi-static case is important, because if one can show realistically that a varactor charged with 2 V can be quasi-statically biased, say over 5 seconds, with a net energy gain, then there is some validity to my argument. I'll write this up, correcting my previous mistakes, when I get back from work today.

The product of this current by the voltage, integrated on the changeover time of C, corresponds to the work that opposes that of the Coulomb force between plates F=q.E, it cannot be lower. So unless you have an idea to get this current from something other than the varicap control signal, there will be no gain.

A priori, this appears to be true. But the same argument can be made against any and all purported overunity devices, unless they describe a new source of energy-- in which case the a priori argument is that no such source of energy has been described in the literature! So, such reasoning, although necessary to eliminate seriously bad ideas, may lead to 'false negatives' in practice. We are justifiably wary of false positives, but false negatives are also deleterious.

In this type of paper, the manufacturing recipe counts much less than the underlying principle. Even if we do not have ferroelectric nanoparticles, we may be able to get around the problem and apply it differently, for instance with electrets.

I agree that there are a lot of ways to go, since we are dealing with a process (parametric amplification) that is not tied to any particular materials. However, the material the authors describe is quite exotic, and I've never seen reference to anything like it before-- which is why it got written up in a journal.
There are some circuits (star/delta) composed of standard R, L, C components that will show a negative resistance, inductance, or capacitance across one leg of the circuit. Substituting one of the components with a variable version of the component could lead to a variable negative capacitance that is easily controllable.

Certainly there are many ways to make a parametric change of a capacitor, but how to do it without it costing us more than we're going to earn, that's the one and only question.

Yes. In all but a few very obscure cases, magnetic components are lossy as they reach saturation, and so I discard them (except for the obscure cases, to be discussed later). The hyperabrupt diodes are my best candidate, and so far there is some indication they may work for this. Early days, though..

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I guess I haven't figured out the 'quote' feature, so the response above is a bit garbled. At least F6LT will know what he wrote :-)

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Fred,
If you precede a sentence with the word "quote" in square brackets and follow it with /quote in square brackets it will appear as a quote on the forum.  Hypertext uses square brackets as markers and the data inside the brackets tells it how to display.  Thus the word "bold" inside square brackets means that following text will display as bold and /bold inside the brackets turns off the bold instruction.
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Thanks, Smudge, I realized that, after I sent it, of course..
   
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A priori, this appears to be true. But the same argument can be made against any and all purported overunity devices, unless they describe a new source of energy-- in which case the a priori argument is that no such source of energy has been described in the literature!
...

I agree with that. Therefore, the idea of a parametric device must include the reason why its behaviour would not conform to the "literature" or could not to be conform.
Otherwise we can try anything, it might take a while :-).

Quote
"However, even with that we got self running for a short period of time, and the reason the device stopped had more to do with matching impedances than with a lack of energy to drive it."

If you have a good lead, go ahead!  O0



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