T-T Fusion in a radioluminescence tube.

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fabian bunbury
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T-T Fusion in a radioluminescence tube.

Post by fabian bunbury » Mon Jun 24, 2019 7:40 pm

I recently saw an old exit sign that was kept alight using a luminous tube containing very small amounts of tritium. It occurred to me that it might be possible to use such a tube in a fusion experiment. If this were practical it would allow amateurs to do away with the cumbersome vacuum equipment that so often prohibits newcomers from achieving fusion. I had a quick search on the internet and found this quite fun video series documenting exactly this. https://www.youtube.com/watch?v=_b1L1Rwlycs. I would be interested to hear what you guys think about this approach to fusion. Has anybody here done it or is it not feasible?

Thanks a lot.

Cai Arcos
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Re: T-T Fusion in a radioluminescence tube.

Post by Cai Arcos » Mon Jun 24, 2019 9:26 pm

Something that bothers me greatly about the video is the high voltage system, since no metering is done and no data presented. Furthermore, If I remember correctly from the cross section chart of the T-T reaction, extremely high voltages would be needed. Those voltages are not present, I would think, seeing solely the quality and isolation of the connections and of the supply itself.

However, I would appreciate an experienced user with more knowledge than myself to post their own observations.

John Futter
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Re: T-T Fusion in a radioluminescence tube.

Post by John Futter » Tue Jun 25, 2019 7:18 am

Fabian /Cai
We do not talk about using Tritium as it is not allowed in any country under IAEA rules
same as taking apart smoke detectors to access the Americium (ie tampering with an accepted package)
So it is on this site, so please do not discuss this further

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Richard Hull
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Re: T-T Fusion in a radioluminescence tube.

Post by Richard Hull » Tue Jun 25, 2019 7:24 am

I, hereby, strongly reiterate what John said. Such posted threads are regularly deleted by me.

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
Retired now...Doing only what I want and not what I should...every day is a saturday.

Rex Allers
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Re: T-T Fusion in a radioluminescence tube.

Post by Rex Allers » Tue Jun 25, 2019 10:05 am

OK about the tritium, but ignoring that, what about his whole experiment? I already wrote this, so...

My first instinct was to just ignore this, but then thought maybe there was something in here that might be a useful tool in evaluating theories and then how to gather and evaluate data then attach some meaning to it -- or not.

This youtube guy calls himself "Dr. Jaynes". Dr. of what? Could I see your thesis, please.

From watching some of his videos, or as much as I could take of each of his videos, I think... He's smart at some levels. He quotes and brings up a bunch of deep physics topics, but he throws established concepts around in a buzzword way that doesn't give me an impression he really grasps what they might mean in the real world.

So you gave one link. There are actually 4 parts in his tritium neutron video series.

1) Tritium Nuclear Fusion Experiment - Part 1
https://www.youtube.com/watch?v=ZWaNpgHUg2I

2) Tritium Nuclear Fusion Experiment - Part 2 Debye Length
https://www.youtube.com/watch?v=DhISVrX3NcM

3) Tritium Nuclear Fusion Experiment - Part 3 Fast Neutron Detector
https://www.youtube.com/watch?v=SsUNg31ZqXU

4) Tritium Nuclear Fusion Experiment Part 4 - Shielded Fast Neutrons
https://www.youtube.com/watch?v=_b1L1Rwlycs

I think number 2 gives some insights to the guy. Starting about 2:35 in, he shows his notebook. Lots of meaningful calculations but no mention of how he chose data as inputs or what the results might mean. At one point he talks about using a magnetron as an excitation source. Very dangerous, if true, but no mention of how that was done. Lots of calculations but no logical thread through them. He states a few assumptions that I don't see any basis for. Nice notebook. At best I can only give him partial credit for the calculations, after his summary.

I get an impression of someone who likes formulas, and calculations, and the feel of theories. I don't get an impression of someone who carefully evaluates the possibilities and then conducts an experiment and gathers all the data possible to show any conclusion.

In #3 he made his own neutron detector based on a plastic scintillator and a PMT. Lots of jibberish followed in the part I could watch.

In video #4 (the one linked in this thread) he now has a new detector that seems to have a PMT, but no mention of what, in front of the PMT, is sensing any neutrons.

So then there is a signal on the scope with a main big sinusoidal signal that he says is noise. You betcha! Let's look at a sample screen capture of the scope from the video.
dumass plot.jpg
It is pretty out of focus but I think the number in the lower left is saying 5V/div. If so, that sine wave is about 18V peak-to-peak. Yep, that is a rock concert level of noise. Is anything grounded?

The time base is hard to read. Looks like 2.00(something) per division. Assuming the big sine is 60Hz, the period of one cycle is then 16.6 mS. I added the vertical yellow lines on the capture pic. The period from the left yellow line to the short right yellow line is about one sine cycle and that is about 8-point-something divisions, so we can say that the horizontal scale must be 2 mS per division. That is: 16.6 mS / 8 ~= 2 mS. We knew it was set to 2(somethings) and now something is proven as mS.

The Dr. seems to think all those small pulses might be neutrons. Hmm, really? They all are about the same size (maybe 2-3 V, yikes!) and they seem to be very evenly spaced time-wise. Looks like more likely switcher supply noise to me.

So, on the pic, I put the two long yellow lines 10 divisions apart. That is a period of 20 mS. I then counted all the small spikes between the two long yellow lines and got 25. So the period of these spikes is about 20mS/25 ~= 800 uS. Inverting, that would be a frequency around 1250 Hz.

1250 Hz is quite low for a switching supply, but in other videos he describes the HV supply exciting the tube as generated by an Arduino. In the #4 video there are no details about how that exciter supply is configured but that would be my first suspicion of the spike pattern source.

The PMT also has a supply. Any details about that? -- no. Another possible source.

And how can you have 18 V of sine noise in these measurements?

-- So, I'd say, the whole video series is filled with clever sounding nonsense. --

A possible thought experiment:

-- If video #4 was your experiment, how would you try to remove all that 60 Hz noise?
-- Would you have a reason to think neutrons would occur as regular pulses?
-- Is there any way you could test your fast neutron detector with no tritium tube before the full go?

In general -- How might one separate clever ideas from clever sounding bullcrap?
Rex Allers

Cai Arcos
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Re: T-T Fusion in a radioluminescence tube.

Post by Cai Arcos » Tue Jun 25, 2019 12:37 pm

John /Richard:

Could you point me somewhere I could consult those rules? I was completely oblivious of it's existence, and the Americium example you provide is quite shocking, mainly because I see it commonly on the Internet in very popular/good reputation sources (for example, this spanish web page: https://sites.google.com/site/anilandro/Home or this YouTube channel: https://www.youtube.com/channel/UCV5vCi ... ZwAOO_FNfQ)

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Re: T-T Fusion in a radioluminescence tube.

Post by Robert Dwyer » Tue Jun 25, 2019 4:07 pm

The cross sections for Tritium-Tritium fusion are incredibly low, and I doubt it is in reach of an amateure, researcher, and I am highly suspect of the physics the video poster is claiming to be occurring.

The proper use of radioactive materials, and including tritium exit signs and Americium from a smoke detector can be found on the NRC website. Any taking apart of exit signs, smoke detectors, etc.. is illegal from at the federal level according to the NRC. Whether or not an agreement state, or the NRC views the violator as worth the effort to pursuit, is up to them. Regardless, it is still illegal.

Below is a link to the Atomic Energy Act of 1963 which spells out a lot of rules and definitions of these things. Below that is a link to the NRC website regarding Tritium exit signs, which is less dense to read. I also attached the NRC website link to the federal regulations, which you can explore on you own if you are curious.

https://www.nrc.gov/docs/ML1327/ML13274A489.pdf#page=23

https://www.nrc.gov/reading-rm/doc-coll ... itium.html

https://www.nrc.gov/reading-rm/doc-collections/cfr/

I have never believed discussion of the physics involving tritium handling, storage, containment, or fusion, should be topics avoided in of themselves. However, one begins to tread on a fine line when discussing actually doing such activities without a liscense and permission from your state or federal government. Ultimately it is up to the forum administrators to decide if a topic crosses these fine lines and may endanger the use of the site.
If we throw more money at it, it will have to work... right?

Cai Arcos
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Re: T-T Fusion in a radioluminescence tube.

Post by Cai Arcos » Tue Jun 25, 2019 8:18 pm

I will carefully read those documents and also inform myself of any other restrictions present in Spain. It had never crossed my mind the (i)legality of my actions, but not knowing about the law does not excuse one for breaking it.

John Futter
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Re: T-T Fusion in a radioluminescence tube.

Post by John Futter » Wed Jun 26, 2019 5:16 am

Cai
Not a problem.
I see that Spain is a member of the IAEA see the beginning of this document https://www-pub.iaea.org/MTCD/Publicati ... 75_web.pdf.
You will have to wade through many of these to find the description of accepted package and what happens when an accepted package is damaged intentionly.

Have a good look through the IAEA website most countries of the world are members except for a notable few --you guess which ones

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Richard Hull
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Re: T-T Fusion in a radioluminescence tube.

Post by Richard Hull » Wed Jun 26, 2019 7:23 am

Rex waded into the original issue. (great summary and conclusions)

From what I can gather the Dr.s neutron measuring technique is not good enough to even be considered wrong...Non-existent comes to mind. So many fail on amateur home efforts to electronically detect neutrons. Stabs in the dark at neutron detection are not to be believed. If you are cobbling together electronics to do neutron detection, we always demand complete and full expositions on such efforts at every turn and component in the system. Neutron plastic scintillators are not a good choice.

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
Retired now...Doing only what I want and not what I should...every day is a saturday.

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