Farnsworth Questions

Reflections on fusion history, current events, and predictions for the 'fusion powered future.
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Nicolas Krause
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Farnsworth Questions

Post by Nicolas Krause »

I think the most interesting aspect of Richard's historical descriptions are when the device does not behave as expected. In the beginning Farnsworth had an idea about how the device operated, it was incorrect, and by reversing the polarity of the power supply, some fusion was obtained. The later descriptions, of transparent ion beams and overexposed radiation badges are also deeply intriguing. I'd like to begin by asking about the hole burned through the vacuum chamber. Is there a plausible mechanism for operator error that could have caused such a problem? For example if the ion beams were set too high could they have burnt a hole through the chamber? I presume if there was some failure of the main power supply, it simply would have melted the whole device, not burnt a hole in a spot.
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Re: Farnsworth Questions

Post by Richard Hull »

Today's fusors are rather thick walled .0625 and are deep dish hydro formed. The Farnsworth systems were spun from thinner metal for the most part. If the guns were set to high power, especially at a deep vacuum, ...And, they pumped deep as witnessed with the ion pumps. It is easy for the mean free path to be long enough so that full energy ions would impact and heat the thin metal walls so that at some point, the vacuum would drag a hole into the fusor.

Both Gene Meeks and George Bain told me that punctures did occur and a close look on some photos, show a little weldment or patch to fix these holes. With the guns in some models finely aligned, Gene noted that they would burn an off center hole in the extractor plate of an opposite gun.

They drove the guns hard and a typical run pressure as noted in some of the runs seen in the attached graphs, (of which there are many I did not post images of), were on the order of just a few microns at 100keV applied. To warrant significant ion-ion beam interaction in the center they maintained a significant mean free path by running at low pressure and high gun currents.

Asking questions like this related to my histories is good as I can expound on specific issues and some nuances that are not dealt with as fully as the questioning minds here might thoughtfully wonder about, as Nicolas has. I hope I have dealt with his question well here.

I would have to check my notes but I was told of at least 4 catastrophic punctures, which really caused internal arcing, oil diff pump flash boilings and general system wide mayhem before power to the device could be removed. At some point Gene installed a "Crash all power Kill" mushroom button on both the Pit and Cave control systems.

Richard
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Farnsworth Questions

Post by Frank Sanns »

Early on with work here on fusor.net, there was discussion about these runaway events. So much so that I did a calculation to see what would happen if all of the deuterium in my chamber actually all fused at once. The physical force would have been about like an M-80 firecracker. The neutron flux would have been on the level of the Slotton incident with the Demon Core. Serious stuff for sure. My first experiments with the fusor were thus with air and not deuterium. Only after some experience and more info on the run a ways from Farnsworth days did I crank up the power and start to push deuterium and higher powers. Still to this day though, I always wear a dosimeter when I am running my fusor or visiting a person running theirs. Just in case some anomaly does occur.

It was concluded that the run a way reactions were really not fusion run a ways but rather power supply run aways. The power supplies were quite beefy and once a fusor got to really rolling, things started to get hot and sometimes very hot. Thermionic emissions would escalate, reduce the series resistance, and create an ever and quickly increasing path for the current to flow. The large power supplies were not current limited so they could deliver a great deal of power to the innards of a fusor that had to terminate somewhere. It is my belief that the large input power spikes were responsible for the chamber melt throughs. Couple this with the lack of activation of the metals that everything around the fusor and lab were made of never because "hot" to their Geiger counter. A neutron excursion sufficiently large to generate that level of heat, would have been sufficiently large to significantly activate metals in the chamber and power supplies as well as supports.

This past January, I had the opportunity to partially disassemble and exam the cave fusor with Jonathan (Farnsworth) Moulton. I was aware of the reports of visible beams coming from the ion guns during my examination so I kept that in mind as I looked at each component and chamber geometry. The very first thing that I noticed about the chamber was that MANY of the insulators for the ion guns had loose insulators. The insulators were floating between metal end cups. This seemed very strange to me and while some were physically broken by handling over the decades, others were just not integral to the metal as a vacuum feedthrough would be.

The ion gun feed throughs were very small compared to the HV voltage insulator on that fusor or on most of our fusers. This surprised me a bit considering the current that they had to carry for the beefy filaments within the ion guns. The wire that was coaxial within the insulators was also not very thick. It was maybe 10 gauge (rod) wire perhaps. I should have measured it precisely but there was much else to discuss and look out so those multiple days just slipped by with other relevant items of interest.

The point is that high voltage needs large insulators for hold off voltage and small diameter wires within the insulator as currents are low for any given power. Power = Volts x Amps. High voltage means not many amps needed. On the ion guns though, that is reversed. For a given power input, the volts are low and the currents are high. The conductors within the insulators need to be robust to carry those currents. In an thermally insulated environment like inside of a ceramic insulator, heat dissipation is not going to be the greatest. Running high power 40 amps+ through a 12 gauge rod is going to heat the conductor and perhaps quite significantly. It is my believe that on the high power fusor runs, that the inner conductor of the ion gun insulators may have been starting to become thermally incandescent. That dull red glow would diffuse though the ceramic insulator and be externally visible. More evidence of this was the fact that multiple beams were seen emanating from the ion guns. There are multiple insulators on each of the guns so believe this a plausible explanation.

None of us were actually there for these events but circumstantial evidence like robust power supplies that were not current limited, or lack of evidence (like no neutron activation) suggest that no new physics was occurring there. There will, of course be those that think something supernatural occurred with some of these events and they in fact may be right. Like I said, none of us were there and the level of instrumentation to properly account for the events was not in place at the time.

Please continue the discussions on this matter here. We should all add our thoughts to see what else might be plausible explanations.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: Farnsworth Questions

Post by Nicolas Krause »

Hi Frank,

If I understand your descriptions correctly, it would seem the simplest way to think about the Fusor would be as a resistor in series with a power supply. When damage to the chamber occurred it was due to some sort of thermal runaway event, basically like putting a 0.5 W resistor in to a circuit with 1W of power and being surprised when it goes up in smoke.
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Re: Farnsworth Questions

Post by Frank Sanns »

The short answer is yes.

The more in depth answer is that the fusor is complex. It acts as a series of resistors that change with vacuum level, voltage, and current. They are all intertwined and dependent upon each other.

Where there is a thermionic run away, the increasing flow of electrons effectively reduce the resistance of the path. It would be like having a variable resistor set to 100,000 ohms then cranking it down to 20 ohms. The current would just build and build as the resistance falls.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: Farnsworth Questions

Post by Nicolas Krause »

Thank you for the clarifications and responses! Are there any records of the direction the research intended to go had funding been maintained at ITT or if Farnsworth had been able to make his company a going concern? I've read the paper Robert Hirsch authored about the fusor research, but beyond that, if he'd been able to pursue further developments did he have any ideas about modifications to the fusor he would have liked to investigate? Did Gene Meeks mention anything similar? From Richard's descriptions of Farnsworth he seems to have had a million ideas, have any of his ideas for future iterations survived?
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Re: Farnsworth Questions

Post by Richard Hull »

All great questions, but rather contestable from many quarters. Ultra Farnsworth dream boosters might say that they were on the cusp of a breakthrough, but were cutoff at the knees. The naysayers, like myself, genuinely believe that they (ITT and the Farnsworth team) had wrung this thing out about as far as it would go, at that time.

Now to your specific questions. I got no real feeling from Hirsch or Meeks that they had the rug pulled out from under them at a critical moment. Hirsch did note that when he became head of the AEC thermonuclear effort, he tried his best to get a small program going on the electrostatic confinement fusion. Unfortunately, he had already "killed" 3 sacred programs left over from Sherwood. 2 mirror programs and the stellarators! He made a lot of high-end fusion enemies. He admitted that this had many in the AEC, poo-poo any attempt to start a small version of the old ITT effort at two universities. Both universties were willing to take it up if federally funded. It did not happen, of course. Hirsch admitted that he still held out that all aspects of the work had not been investigated. This is not my impression, these were from Bob's own mouth.

Who knows where Phil's brain was at PTFA. I am unaware of a group of notebooks or a filing cabinet full of Phil's ideas on fusion from which we might try to glean some insight into his thoughts. Many of his modern day supporters believe that his ideas were never investigated in their purest form. The best among them, who are qualified to question whether the purity of his work was ever really tested, are currently more focused on recovering lost energy that exists within the fusor. Unfortunately, such efforts are purely speculative and not one hand has been lifted to do the work among the hopefuls.

There are so many supposed "forgotten geniuses" that promised much and who were just secretive enough to leave long lingering questions with their passing. Farnsworth is but one. Tesla is another, T.T. Brown and many others of this venue have adoring followers and virtual cults formed around the more bizarre claims that never saw any development by their object of adoration.

We are where we are in IECF and the fusor work. What might be considered more advanced work in the field, in the interim, might best be summed up as being that of the University of Illinois and the University of Wisconsin. None have seen a significant advance, being pretty much long running student research efforts. Admittedly, they have really pushed the envelope with a number of innovations, but none have moved forward to any significance so far as fusion energy is concerned.

In Summary: I have no idea related to Phil's thoughts, before, during, or after the ITT program. I have no reason, based on extended discussions with Meeks and Hirsch, that they felt they were on a directed path towards great improvements in 1968 at the end of the project. Hirsch, as of 1999, still loved the idea of more research on IECF. For me, IECF is more or less a dead duck for power-ready, controlled fusion. It is the easiest and least costly way to actually do fusion, of this, there is little doubt. This is why I continue to pursue it.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
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Re: Farnsworth Questions

Post by Frank Sanns »

Having been on the team that had the opportunity to examine the Farnsworth archive this past January, I have to say that there was much more there than what has yet been reported. Most of it was other technologies that include heavy metal removals, water purification, lasers, and other items. These materials will be released once it is all compiled and put into a form that digestible by those that that view it.

Related to fusion, there were some interesting drawings and configurations that for whatever reason, never came to fruition. Some of them were technically interesting. Yes, energy recovery and recirculation were some of them but the actual focusing of the beams to locations at will is a very interesting concept. It is also interesting that it was taking inside of a large volume space that was essential a spherical drift chamber.

At the time, the ion guns were archaic compared to developments over the last 50 years so they fought with them to get them balanced. Today, those kinds of experiments and the instrumentation would make studies far easier.

Do I think there is more work there to be done? Yes, absolutely. Do I think it will have a Q much greater than 1, maybe, but I doubt it. From the devices and drawings that I saw, I think, if nothing more, some good studies could shed light on some of the phenomenon that we see in our fusors.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: Farnsworth Questions

Post by Richard Hull »

Pem, in her book touches on some these lofty Eco-friendly efforts that Phil dreamed of to be encompassed by PTFA. Unfortunately zero traction was gained by any of them to bring in the much needed cash to keep the store open. Lofty and laudable goals with no money behind them never feeds the bulldog to keep him at bay. I have seen a number of the letters of some desperation fired back and forth between PTFA and various entities. In them, PTFA is looking for contracts, opportunities and funding. These PTFA letters are typically answered with great delicacy, but ultimately refusing either interest or funding. Some returns do express great interest, especially the Air Force, but fain no funding exists "at this time".

The world moved on without PTFA and usable nuclear fusion energy.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
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Re: Farnsworth Questions

Post by Nicolas Krause »

Hi Frank,

What exactly is a spherical drift chamber? I haven't come across that term before.
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Re: Farnsworth Questions

Post by Richard Hull »

Frank may also speak to this question.

A linac accelerator is intrinsically a drift tube in which many hollow cylinders of increasing length are aligned and fed with a high power, high frequency signal such that electrons or ions entering the drift tubes are accelerated. A concept of spheres within spheres with multiple orifices might also create the same result, but with far more energetic net beam convergence at a single point. This is a nice idea, but has yet to see any physical embodiment. Such a system was loosely looked at by the original Farnsworth team with their single internal dynode systems. The issue of importance is how many spheres within spheres are possible and or desirable due to the complexity that each must be fully isolated and insulated from the neighboring two spheres all of which require separate external connections.

Far less complex and easier to implement would be a spherical arrangement of linacs arranged to focus to a single point ala the NIF laser system. The spherical drift system is a great concept, but again, just an idea and theoretical musing. If possible to realistically implement, such a spherical system might prove an interesting construct. Multiple linacs can be made simply and inexpensively if made in quantity at fusion voltages under 100 keV. A 100 keV linac is a snap to make compared to the 5-10 meV linacs of research. An initial spherical drift system for experiment would be complex and, at the early stages of investigation, would involve far fewer spheres than found in linac drift tubes. This would allow for less costly, ($1 million) implementation, but might be a proof of concept system. That very cheap million dollar figure would not begin to pay for lab, staffing and related equipment to investigate and assemble the cheap million dollar device. Such a device would certainly never do usable fusion, but might move the per watt input versus fusion energy output several orders of magnitude forward.

The beauty of the spherical drift system would be that if you could implement this into a physical reality, the number of "effective linacs" in the system might be limited only to the number of concentric precisely aligned holes you bore into the multiple spheres!

Near microscopic ion drift tube sources at the very low power 3-5kv ion source level are currently used that can plug into an IC socket!! Most are used in small mass spectrometers.

Like Frank says 60 years have passed since the ITT effort. Modern miniaturization is amazing and some firm which might seek to use this concept in the vein of IECF might bear the expense of developing something quite compact as a proof of concept, linearly or perhaps even spherically. Anything along the original Farnsworth musing back then would have been larger and far more tough to implement requiring far more money than ITT could supply and as regards PTFA, a bridge light years beyond their grasp. As with many landing here with ideas, they have no money or the "doing" interest or ability. Ideas are a dime a dozen. Implementations of those ideas are always another matter.

Check this out

https://link.springer.com/article/10.10 ... 19-00248-w


Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
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Re: Farnsworth Questions

Post by Frank Sanns »

Thanks for the info Richard.

To continue and clarify my earlier statement, there were some design elements of the Cave Fusor that were interesting. The ion gun side arm was fed through a small hole in a larger otherwise solid inner cathode. There were six such ion guns and six small holes in the inner cathode. The entire cathode was at operation voltage which in at least one photograph, was set at 62KV.

The ion gun then spewed out fusible ions (deuterium and or deuterium/tritium mixtures) which only had a small acceleration gap until it entered via the orifice into the large solid cathode. Inside the cathode, there would be no work done on the ions since there is an absence of a field inside of a conductor. The focus set outside would not be distorted by our current fusor inner grid wires. It would stay focused except for the normal defocusing that happens when you have a bunch of similar charges repelling each other.

So the Cave fusor had a single drift sphere. That is an interesting arrangement but what I had envisioned was an extension of that using multiple spherical drift chambers with acceleration going on between strategically placed ones. To further what Richard has said, a linac for example uses an RF field and a series of hollow cylinders along its axis. A charge is accelerated towards the leading edge of the cylinder by the RF field. During one cycle, the RF is negative so a positive ion would see acceleration. The the RF cycle would go into opposite phase. At this time the positive ions would be traversing the inside of the cylinder and not feel any RF potential. They are "timed" to emerge from the cylinder to just at the moment the field goes negative again. They would be accelerated to the next cylinder picking up energy as they were accelerated. Again they traverse the gap between the tubes and at the right time enter the next tube to continue along their axial path unimpeded by any external RF fields. As the ions gain energy (speed), each successive drift tube is longer and longer to shield the ions as they move through the system. This is a simplified version of what happens as both phases are actually used to push and pull the ions but it complicates the concept for this post.

What I imagined then was to take what Farnsworth had done and jump it up to a set of nested spheres that would use the same RF principle to accelerate the ions from the ion guns. This would allow for much higher collisional energies without the need for ultra high voltages to be applied. This has significant advantages for efficiencies in a fusor.

No I have not yet build this yet but it is an intriguing variation on an initial idea that was present in that cave fusor.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: Farnsworth Questions

Post by Richard Hull »

As Frank notes, timing is everything and a lot of careful calculations force the mechanical design say even in the three nested sphere system. The RF power would still be very high even if the applied vlotage is rather low. This is the same with a the cyclotron. You can't get something potent in output without a far superior potency on the input. Make no mistake about this. In the end, nested spheres is a great idea.

The other aspect is will we need and ion gun for every hole?? Not necessarily. Think on this aspect. See if you might noodle this statement out.

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Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Re: Farnsworth Questions

Post by Nicolas Krause »

Hi Frank,

If I recall correctly, Paul noted that the Farnsworth cathode had a number of einzel lenses on it, but I believe he was referring to the large ports. Were the small ports for the ion streams einzel lenses as well, or were they simply passive elements? In addition are there any engineering drawings of the actual assembly of the cathode? I've been pondering the design for a bit, and have some ideas about how I might go about implementing an einzel lens on a sphere, but I'd love to see how the problem was solved originally. I'm also operating under the assumption all the einzel lenses on the cathode were operating at exactly the same voltage levels, was there ever any consideration given to the ability to "tune" different lenses via some sort of variable voltage control?
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Re: Farnsworth Questions

Post by Dennis P Brown »

Frank, you appear to be assuming that higher energy ions alone somehow offer an advantage in fusion. Since fusion in a fusor is by tuneling, higher energy ions above what has already been shown to be ideal simply waste energy and will not increase rates of fusion via that process. If you are simply using brute force collisions to create non-tuneling fusion, again, much above the energy required to over come the Coulomb force is just wasted energy. What I would think is better are more fusion capable ions (current) of proper energy.

Nicolas, the classic electro-static accelerator tube using such lens does exactly what you are suggesting.
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Re: Farnsworth Questions

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We must remember the wisdom to be found in the Lawson criterion's 3 key points! ( cross section -tunneling probability), energy of the particle, confinement, and time of confinement.

The more ion energy be it in velocity space or in collisional events which the ion guns force in the "cave" device the more fusion, tunneling or not! Likewise, the increased amount of fuel present, (ion current), at high ion energy means more reactions in velocity space or collisional space meaning more fusion. As neither machine is involved deeply in genuine, realizable confinement, the third Lawson term, that issue is rather moot. However, what volumetric ion kinematics we have acts over an infinite period of time, (fusion for as long as we run the machine).

Two out of three ain't bad, considering we will never do any power fusion. Actually, any one fusion device, at the amateur level, regardless of design, is hard pressed to do more than just one of the three goals to any real focused advantage without letting one of the other criteria be any more than merely fortuitous or aiding, at best!

We have noted that, regardless, our fusors tend to use many fusion scenarios in a lot of interesting and, at first, unsuspected ways. Everyone of these little unsuspected fusion benefits that are brought to bear, helps. Yet, due to its simplicity there are also a lot of wrong headed and limiting factors thrown in the mix. We take the good with the bad and come out smiling at the amateur level. We are doing fusion!

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
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Re: Farnsworth Questions

Post by Frank Sanns »

Nickolas,

For some reason this thread fell under my radar. As it turns out, the design I thought was Einzel lens were not. They were to confine or recycle in electrons. I also looked more closely at the drawings that were posted here in one of the threads and that indeed is what was trying to be done. A multipactor approach rather than a collimated Fusor approach. I have yet to see any convincing evidence that the multipactor was a productive path to fusion.

Lensing though into the spherical drift tubes though is very interesting to me. And yes, micro adjustments of the focus elements could ensure precise alignment at all current and magnetic and electrostatic field contributions. I think this is an area for work. If nothing more, it can shed more light onto the inner workings our of fusors.


Dennis,

I do not think more energy is good. As say the right amount of energy is the solution sort of. While infinite current will produce essential zero fusion at 1 volt, it does not really get much better up to around 5 KV. As the voltage rises above 5KV things start to happen and begin to plateau (for D-D fusion). It is a log scale so really the cross section does not really maximize until over 200 KeV. It would seem than that the ideal voltage for fusion would something just under that so that the maximum number of fusions will occur per incidental collision.

I think this will affect the recombination force-time to but I have to work through that one as I am a bit foggy this evening. I think I need to take up drinking during this quarantine that is just now finally lifted only to be told the past few days not to venture out because our city was looted.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: Farnsworth Questions

Post by Richard Hull »

I have always noted that for D-D fusion, 100kv is the effective amateur limit if you have under $100,000 to invest in the marginal gain to reach 200kv. Very few people have any concept of the added costs and expertise needed to fabricate, insulate and work at useful currents in the 200kv range. So far no amateur has come really close to 100kv applied. The true fusion gain of a full 100kv beyond 100kv is truly marginal in the cross sectional regime which rules all fusion. The real useful payoff for the amateur is over 30kv but the top end with $10,000 spent from a cold start might be 80-90kv.

Most of the breakdowns in the Farnsworth team's recorded work result at voltages over 100kv. Arcing was the big issue. They spent over $6,000 on an early Linde artificial sapphire rod 3/8" in diameter to suspend the inner sphere against break over arcing. (Story from Gene Meeks who would say it was one of the biggest wastes of cash in all the team's effort, but Farnsworth wanted it.) This was in 1966 when budgeting allowed for it. Even 100kv is very tricky if you are running increased pressure to allow for more fusion fuel. A quick check shows runs that worked over 100kv were at 5 microns pressure and very low currents. They tried to trade cross section, (KV applied) for fuel pressure and fusion current. I am actually stunned that while using D-T they went over 100kv!! I attach a cross sectional chart......D-T cross section actually drops beyond 60-70kv! We see that less than one order of magnitude will be gained in cross section between 100kv and 200kv in D-D fusion. Is the effort really worth the pain and expense at the amateur level? Some one with experience, drive, good hands-on fusion knowledge, fat wallet, and the needed space might give it a shot.

Unless the blown-up, hopeless dreams of Kent Farnsworth and several million dollars are brought to bear on any pure IECF fusion, it is unlikely much in the way of advance can be made. This is for sure and for certain in the hands of amateurs unless some sort of group project is hatched, which is highly unlikely beyond a lot of high spirited righteous discussion with an attendant mighty gale of wind over the decks as is so typical of such really positive "starts", followed by stagnation and dissolution.

Question, where is this sapphire rod today? Needless to say, such a rod might be obtained for only a few hundred 2020 dollars, now, as such artificial, beyond gem grade, pure materials are common now.

Richard Hull
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Re: Farnsworth Questions

Post by Frank Sanns »

I understand all of what you present Richard. The relative fast increases in cross section really start to level out above 110 kev. From this alone, there is no reason to go higher.

There is however, another factor that needs to be considered. That is the area under the curve. It is not just a 1:1 fusion event. It is a minuscule event because of the tunneling statistics. At higher energies, there are more chances at fusion occurring in subsequent collisions. Once you have a high energy particle, it will bounce around off of other atoms. More of these collisions can occur that have the potential to yield a fusion collision until sufficient energy is drained away.

MFP is dependent upon the energy of the deuterium. At high energies, higher pressures can be used. Higher pressure means more available fuel per unit volume and that too is important to the overall efficiency to fusion.

The optimum conditions for maximum fusion energy is NOT just based on the cross section curve.
Achiever's madness; when enough is still not enough. ---FS
We have to stop looking at the world through our physical eyes. The universe is NOT what we see. It is the quantum world that is real. The rest is just an electron illusion. ---FS
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Re: Farnsworth Questions

Post by Nicolas Krause »

Has there been any research done in to non-linearities in the fusor setup? Star mode is an interesting configuration whereby the plasma seems to organize itself in to a non random structure. I appreciate that at the time that a lot of the initial work in chaos theory and non-linear dynamics was being done, such as Lorenz's weather model, it was the 1960s and 70s and its highly unlikely the initial Farnsworth effort would even have been aware of the mathematical developments. However, I was wondering however if anyone is aware of any subsequent developments, mathematical models or simple experiments related to the fusor?
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Richard Hull
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Re: Farnsworth Questions

Post by Richard Hull »

Frank, I have long called for the Lawson criteria here in hundreds of posts. Energy at cross section, pressure, containment. No one on earth has run a fusor at real high energy, high pressure fuels and high current. All fusors will and forever suffer at very high energy ions, being forever limited to operate at low pressures and low currents. I doubt if anyone ever will..... Certainly, never at the amateur level. By this I mean 200kv applied, 100 microns pressure and 100 ma current or better. This would be a fusor breakthrough leaving us only 7 or 8 orders of magnitude away break even! I am really waiting for someone or group to belly-up to the bar to "show me".

Nicolas, "Star mode" means absolutely nothing in relation to the fusion process! it does indicate a, clean, somewhat limited, symmetrical, internal operational regime. There are no instability issues in the fusor as built here. The fusor is a bungling mass of disorganized, bull headed electrostatic goings-on in an ionized plasma that cannot help but fuse due to the very uncontrolled nature of the effort. It is mostly a velocity space fusion system with a bit of target-fusion coupled with fortuitous re-ionization possibilities. Working against all of these fusion methodologies is the bedlam going on through out the device. There are no instabilities in the system because there is no attempt at stability in the very simplicity within the device. We have enumerated in many posts over the past years the exact mechanisms pro and con that we think are going on in the simple fusor.

Add multiple precision ion guns, several biased internal, ported,shells and perhaps ultra-high frequency, high voltage, high power oscillators to get a bare, hoped for improvement in stability and control of the processes involved and.....Who knows?

We have what we have, it does fusion. In this ball of bedlam, the simple amateur fusor, mathematics is the outsider regarding any precision of understanding. Certainly no trained physicist familiar with fusion and plasma would give it the analysis you seek as it is just does not show any merit or display any chance of re-paying the effort involved. Too many variables and processes coming to light only from empirical experiment and, perhaps, processes not even identified at this time, 20 years later.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Dennis P Brown
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Re: Farnsworth Questions

Post by Dennis P Brown »

As I've posted before, fusors, no matter the number of ion guns or increase in density or other tricks these devices will never even match the Sun for energy output (on a volume bases) much less exceed it. In the Sun, even at a million times our atmospheric pressure and millions of degree's C the net fusion via tunelling runs at all of about 300-500 W/ m^3 per sec (try figuring out how much hydrogen and deuterium is in that cubic meter - I did that once and it is vast.) That is barely more power than what the average fusor puts into their device. If those vast pressures and temps produce such tiny amounts of released energy, what is any fusor under vacuum ever going to achieve? Give it a rest; no way will a fusor based on tunnelling ever give real power (above net.) When you think about the conditions in the Sun's core and its puny energy release - trying to get a fusor to exceed even this rather unimpressive level is just plan silly.

On the otherhand, without this strong restriction, life would never occur in the universe since otherwise, star's would burn up in no time. We should be happy that tunneling is so ineffiecent.
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Re: Farnsworth Questions

Post by Richard Hull »

Tunneling is a mere rolling of the dice......... the P-P cross section is so miserable coupled with casting the of dice, solar fusion is pitiful. The solar core temps are also rather pitifully low. (thank goodness) Also written and calculated out in past posts years ago.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Nicolas Krause
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Re: Farnsworth Questions

Post by Nicolas Krause »

Have any of Farnsworth's notes survived to the present day? In reading Richard and Frank's recent posts I was struck by how so much of the discussion of his ideas has to rely on secondary sources. I would love to see any scrap of paper where he wrote down his ideas about what he was trying to accomplish. I think I am consistently struck by how someone who was so wrong on details (ie: polarity of the grid) could also be so right in generalities. This is a man with very little formal education, and yet he laid out a device that produces respectable rates of fusion compared with the huge mega science projects. I understand his explanation of what was going on was incorrect in the device, but he still built a device that when you flipped the wires powering it, it magically generated fusion.
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Re: Farnsworth Questions

Post by JoeBallantyne »

Yes, many of them. The Marriott Library at the University of Utah has a large collection of Philo Farnsworth papers.

The vast majority of which are technical. Included are lab notebooks from Hirsch, and Meeks, as well as Farnsworth.

I have about 30+GB of pictures of said material. I took said photos in the late fall of 2019. I ran out of time to take pictures of everything, since it is a very slow tedious process, but I believe I got photos of most of the fusion related material.

Philo was brilliant, and IMO understood a lot more than what Richard gives him credit for.

My 2 cents.

Note that I would be happy to share the pictures of the above material.

Joe.
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