Neutron Scintillation Tube/Counter

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
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Dennis P Brown
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Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

Again, I am getting done one of the last delayed projects from a year ago: this case, the neutron scintillation detector system.

I have neutron sensitive plastic (3 inch diameter, 2 1/4 inch thick; this plastic rejects gamma's; I believe it is BC-412 or the like.) Also, I have a photo-multiplier tube and the oil required for optical mating of the surfaces. And of course, a mating connector for the PMT.

I just assembled the main tube/scintillation plastic with oil and sealed (silicon sealant) this assembly in a plastic tube that the PMT/scintillator with its tape just fits into (see picture below.)

The end of the scintillation plastic (opposite to the PM tube) is covered with Al foil and I used the same oil to mate this to the plastic/PMT assembly. The foil is both highly reflective and smooth; with the oil, this should provide a high reflective surface to increase any scintillation events within the plastic back into the PMT. I am only interested in signal strength and not calibration. My driver/reader will be near the best voltage but barely.

This complete assembly is sitting on a square aluminum plate. A matching aluminum tube snugly fits over the PMT-scintillator & plastic tube. Then the lower plate bolts to that of the end of the square Al tube.

I need to shorten the square Al tube by six inches before I do the final assembly. The other end plate has a coaxial cable connector for the high excitation voltage & signal feed out. The PMT ground is the Al case and connecting coaxial cable jacket.

Hopefully, this both works and my ST-360 does not have noise issues like it does for my He-3 tube. That is an issue I will have to address later.

Since the ST-360 works fine with my gamma/x-ray scintillation tube I am hopeful it will work with this neutron scintillation detector.

My gamma ray scintillation detector end socket has a capacitor across the high voltage and ground pin. I was wondering if I should do the same for this tube (and wonder why this is done at all?) If anyone knows, please weigh in - thanks!


Neutron Scintillation Detector Assembly
Neutron Scintillation Detector Assembly
Silviu Tamasdan
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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

I actually have a BC-412 scintillator very similar to yours. It's 3inx3in and mated to an appropriate PMT.

It will have a gamma problem. I don't know why you think it rejects gammas. It responds to gamma radiation quite nicely. I actually never used it for neutrons (though I could). It should respond to fast neutrons, but you will have difficulty separating those events from ambiental gammas. In fact it is sensitive enough that I can discern a few ounces of potassium chloride with it - higher counts when it's close that when it's away.

Here are some quick stats from a recent run with my BC412.

Background

Code: Select all

Interval, min: 10:00
Trigger, mV: -15.0
Range, mV: 1,000.0
CPS
Average: 80.8
Deviation: 9.4
Total: 48,468
Double Events: 6,146
Rejected: 2,910
Noise: 19,524
With KCl sample (about 5 ounces)

Code: Select all

Interval, min: 10:00
Trigger, mV: -15.0
Range, mV: 1,000.0
CPS
Average: 98.8
Deviation: 10.7
Total: 59,262
Double Events: 7,293
Rejected: 4,682
Noise: 22,636
With 10uCi of 137-Cs

Code: Select all

Interval, min: 10:00
Trigger, mV: -15.0
Range, mV: 1,000.0
CPS
Average: 782.0
Deviation: 29.6
Total: 469,190
Double Events: 90,741
Rejected: 8,084
Noise: 133,559
With a 2x2x2cm cube of LYSO (lutetium yttrium oxyorthosilicate, contains 176-Lu)

Code: Select all

Interval, min: 10:00
Trigger, mV: -15.0
Range, mV: 1,000.0
CPS
Average: 128.4
Deviation: 21.6
Total: 77,049
Double Events: 10,686
Rejected: 2,956
Noise: 31,528
My BC-412 detector is the fat one next to the corona tubes in the picture below.

Let us know how the testing with yours goes; but AFAIK there is no plastic scintillator that responds only to neutrons, not gamma.

Also regarding decoupling capacitors, what I've seen done is a capacitor from the cathode to the last dynode (the one next to the anode); I've not seen it going from the cathode to the anode. I'm not an expert on those things.
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Dennis P Brown
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Re: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

The data sheet on the plastic via the company indicates it does not see gamma's above 5 MeV; whether that is an issue for my system is yet to be determined. (here is the source for the data: http://www.hep.phy.cam.ac.uk/~lester/te ... _Sheet.pdf)

Still, I can only drive it up to 1200 volts (it can handle up to 1500 volts) so not sure if I will reach its optimum plateau or not.

Also, still wondering if I should put a capacitor across the HV (cathode) to last dynode pin (thanks for that correction, Silviu; as best I can tell, most do.) Just I'll add the caps as per most sites suggest. Not difficult to do since I have 2 kV caps in the correct size - assume it helps reduce depletion of charge on the dynodes.

Found a site where someone uses my specific scintillation tube and wires it up for use with a std geiger counter: http://www.diyphysics.com/wp-content/up ... -Probe.pdf

Here is where they convert a V-700 (or not so cheap anymore - unless you have one, hardly worth the cost considering the step-up transformers tend to fail and have no replacement; so definitely not worth buying for the conversion.) So, if you have such a unit, converting this surplus geiger counter into a scintillation reader/driver might be worth the effort (not adding a counter, however ... ): http://www.prutchi.com/pdf/radiation/CD ... torial.pdf
Last edited by Dennis P Brown on Wed Nov 15, 2017 9:50 am, edited 10 times in total.
Silviu Tamasdan
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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

I don't think gamma above 5MeV will be a concern; I'd be surprised if you'd generate any of that with a fusor. But 50-100keV Xray/gamma will be a problem. And background radiation. As you see from my data above, BC412 reads about 80cps of background in my location.

As for the optimum voltage, my probe uses a XP5312 which works from 800 to 1100V. I found that it behaves in a fairly linear way from 900 to 1050V, but not so well behaved at the ends (800 or 1100V). If your PMT goes to 1500V, then 1200V will likely be enough IMO to put it in the sweet spot or close.

Capacitor: I've wired 2 PMTs on my own, and in each case the instructions I got with the tubes had me put a capacitor not from anode to ground, but from the last dynode before the anode to ground. The anode itself was not decoupled. They both work as expected. Not sure if the capacitor is required, but since the instructions had me put one there, I did.

You may want to look up seller "iradinc" on ebay, he sells a number of PMTs and kits at much better prices than the site you linked to above. He's the one I got most of my scintillation stuff from. For instance a Hamamatsu R10133 3-inch PMT complete with wiring kit and mounting hardware was about $60.
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Dennis P Brown
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Re: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

Thanks for the comments and explanation on the PMT! Fixed my post.
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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

I did a few tests with my BC412 probe and a Po/Be source to see exactly how well it works with neutrons. The gamma radiation is a big problem with trying to use this as a neutron detector. I'm pasting some results below, draw your own conclusions.

I used my 3-inch BC412, in a lead castle (pretty flimsy because I don't have enough lead). For the testing I checked 5 minutes each the background and the PoBe source with 3cm lead, 1.5cm lead and no lead between the probe and the source (or the place where the source would have been for the background tests). A caveat is that because I didn't have enough lead, I had to remove one whole side of the lead castle to use in the 3cm tests; and for that reason I decided not to put that side back when running the tests with the other lead thicknesses but rather leave it open so conditions varied as little as possible.

I then checked a gamma spectrum of the Po/Be source with a NaI(Tl) detector. Attaching the gamma spectrogram at the end (with background subtracted). The peaks I'm seeing are approx. 11.7keV, 83.3keV and 847keV.

Background, 5min, 3cm lead

Code: Select all

Interval, min: 5:00
Trigger, mV: -20.0
Range, mV: 2,000.0
CPS
Average: 21.0
Deviation: 4.9
Total: 6,310
Double Events: 800
Rejected: 319
Noise: 2,546
PoBe source at 10cm, 3cm lead, 5 min

Code: Select all

Interval, min: 5:00
Trigger, mV: -20.0
Range, mV: 2,000.0
CPS
Average: 25.3
Deviation: 5.5
Total: 7,575
Double Events: 990
Rejected: 302
Noise: 3,181
Background, 1.5cm lead, 5 min

Code: Select all

Interval, min: 5:00
Trigger, mV: -20.0
Range, mV: 2,000.0
CPS
Average: 22.7
Deviation: 5.0
Total: 6,815
Double Events: 988
Rejected: 296
Noise: 2,903
Po/Be at 10cm, 1.5cm lead, 5 min

Code: Select all

Interval, min: 5:00
Trigger, mV: -20.0
Range, mV: 2,000.0
CPS
Average: 31.8
Deviation: 6.7
Total: 9,550
Double Events: 1,399
Rejected: 310
Noise: 4,029
Background, no lead, 5 min

Code: Select all

Interval, min: 5:00
Trigger, mV: -20.0
Range, mV: 2,000.0
CPS
Average: 28.9
Deviation: 6.1
Total: 8,656
Double Events: 1,350
Rejected: 293
Noise: 3,834
Po/Be at 10cm, no lead, 5 min

Code: Select all

Interval, min: 5:00
Trigger, mV: -20.0
Range, mV: 2,000.0
CPS
Average: 54.7
Deviation: 7.8
Total: 16,409
Double Events: 2,507
Rejected: 311
Noise: 7,309
My interpretation is: the background does increase a bit as I removed more lead, but the counts that the source generate raise a lot faster. The neutrons shouldn't be affected (much) by the lead, so the raise in counts is likely due in large part to gammas that the source generates and which the lead shields. To elucidate I took the gamma spectrum of the Po/Be source with a NaI(Tl) probe which does not count neutrons at all. Picture below (with background subtracted). The source does generate gammas with energies around 11.7, 83.3 and 847keV (the numbers on the X-axis are not energies but channel numbers; I calculated the energies of the peaks by comparing with a 137-Cs spectrum taken with the same probe).

In my opinion if you want to use a BC412 probe for neutrons, be prepared to use some heavy lead shielding. I don't think 3cm would be enough.
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Bruce Meagher
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Re: Neutron Scintillation Tube/Counter

Post by Bruce Meagher »

If you want to detect fast neutrons properly with these plastic scintillators you need to implement pulse “shape" discrimination. The shape of the light output from a gamma event compared to a neutron event (longer tail) is sufficiently different that it is relatively straight forward to design a circuit to discriminate these events. See my previous post viewtopic.php?f=13&t=11444&p=75597#p75597
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Dennis P Brown
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Re: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

I would think that Fusor's produce a low gamma ray output compared to the neutron signature (when thermalized.) In any case, I have some massive lead shielding if I need it (a very heavy/thick Pb brick so, that is covered ... as long as I don't drop it ... lol.)

Fast neutrons, are an issue since the detector is sensitive to those but I'd think sensitive is a misleading term relative to number of actual events in the scintillation material. Pulse shape discrimination is, of course, the proper procedure as you point out.
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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

You will need lead not only on the fusor side, but on all sides... you want to shield not only from fusor gammas/Xrays but background radiation as well. Reduce the noise as much as possible _before_ discrimination etc.
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Re: Neutron Scintillation Tube/Counter

Post by Rex Allers »

I'm inclined to agree with Silviu and Bruce that your BC-412 may be fairly sensitive to other things besides neutrons. Maybe some lead around the detector will help blocking things other than neutrons. But leaving that, you also seemed to not be too sure about the how and why of capacitors in a PMT divider chain.

Photonis doesn't make PMTs anymore, but I found this link that still seems to work to a general document they wrote about using PMTs.

http://lmu.web.psi.ch/docu/manuals/bulk ... basics.pdf

Page 24 of that document (I think pg 18 in the pdf file) has a section titled "Decoupling (Reservoir capacitors)" that covers this subject. I think it is one of the clearest and most detailed I have seen.

Hamamatsu also has a PMT handbook that you can find on the web that is good and covers similar material.

For a scintillation-type detector that is more specific to neutrons I think you could look at the ZnS-based detectors like this page from Eljen
http://www.eljentechnology.com/products ... -detectors

That page also shows commercial equivalents from other manufacturers. I think these don't show up very often in places like ebay and they tend to be expensive. They are also not very sensitive, so maybe not an ideal alternative.

Keep us posted if you continue down this path.
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Richard Hull
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Re: Neutron Scintillation Tube/Counter

Post by Richard Hull »

I have said it before. It is the devil's own work to use any bulk scintillator and PMT to successfully and honestly report neutron numbers.

My first neutron detection with fusor III in 1999 was with a Bicron special gamma insensitive, 2", ZnS:Ag ringed, lucite, fast neutron scintillator. This little marvel cost me $350.00. I carefully attached it to a Hamamatsu 10 stage PMT. It worked great! But at a manufacturer quoted efficiency of 0.1%. I struggled to get more than 15-20 counts over 5 minutes of fusor III operation. Background was forever 0-1 count over 5 minutes. Almost nothing lit this puppy up, though I am sure a lethal hail of fast neuts would have it humming right along. However, with such a blast, a GM tube held near your silver teeth fillings or wedding ring would be a cheaper solution.

I left that Bicron scintillating dud in the dust and used my rem ball, (BF3), for a year or two. With fusor IV, in 2004, I spent $250.00 with Don Orie at O.E technologies and picked up a Reuter and Stokes 24" long, P4, 3He tube and have never used anything other than that super detector ever since.

Scintillation, neutron counting is for the birds and I doubt I would favor granting neutron club membership based solely on a scintillation system.

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Dennis P Brown
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Re: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

Richard, thanks on the insightful comments; I know they are based on years of practical experience and tend to prove prophetic ... especially for us "gotta see for our selves folks ..." .

Your points are all valid but since the neutron scintillation detector is finished, might as well test it this weekend. Besides, since my russian made Boron Trifluoride (BF3) tube based system is still in repair mode, I have some time on my hands to try this ...just wish it was more likely to work than not.

I do not really expect good results but will find out and I do enjoy doing the construction and research on these projects.

In sum, this is more a project of curiosity since I know I have neutrons. Yet, I want to try other detector systems to compare - most likely a wasted effort (been there, done that a lot lately.) Of course, repairing the issue with the ST-360 that is causing the problems reading my corona tubes will shift to a higher priority status after this is done. That is, creating a proper noise free signal is the next project after this PMT system. Just that since I already had the components for a PMT system on hand and I decided it was time to assemble and test such a detector.

I have a lull anyway while doing the repairs on the Van de Graaff - that is preventing me from doing any real testing on that front - so, just being busy in the home lab! Needless to say, this accelerator project is still the biggest windmill I am fighting ah-la Don Quixote ... lol.

Aside: after reading up on design of PMT's, I see that the caps on the last two or three dynodes is generally required if depletion of the charge occurs on these during heavy signal events ...maybe an irrelevant concern for a neutron scintillation tube assuming any gamma ray secondary showers should not create significant depletion cascades in a detector with such a small scintillation volume. Also, for anyone expecting a series of very fast signals in the unit, such caps would tend to cause discrimination issues, I would think; for a fusor, not a likely occurrence, I would suspect.
Last edited by Dennis P Brown on Thu Nov 16, 2017 9:47 am, edited 4 times in total.
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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

Don't worry, in a sense we're all old Spaniards trying to get our horses to move along. Occasionally we end up giving each other's horses a nudge. It's all good.

This BC412 detector of mine was never intended for neutrons or for fine discrimination of gamma spectra. I bought it for background/safety checks. I hope that it may also be useful in future prospecting trips (it's just at the edge of what I would call too bulky for a portable detector).
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Dennis P Brown
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Re: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

Et tu, Brute? First Richard and now you ... LOL

OK; so, I guess I will expect no results this weekend and will assign the unit to the self for my backup detectors for x-ray testing ...well, at least my project to add a digital counter to the GM unit is looking up since I will have a number of detector tubes to use with it. Also, learned a bit of useful information on these units as well as building skills. So, that is a minor plus coming out of this project.
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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

Seriously, I applaud your neutron scintillation effort... but I'm going another way. Especially since my current setup doesn't allow for advanced pulse shape manipulation. But I'll watch this thread with interest.

Knowing how to wire and bias a PMT is always useful. My latest build is a monster 3x3inch NaI(Tl) crystal with a 3" PMT (the parts including crystal cost less than $250). The gamma spectrum I posted above was done using it. Hoping to do some neutron activation experiments with it.
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Re: Neutron Scintillation Tube/Counter

Post by Richard Hull »

When U hunting, absolutely nothing beats a scintillation counter. The world famous TSA scintillation counters are the absolute best. When in the high dessert of Utah, I left my GM counter back in the motel room and found the good stuff up to 1 foot underground! (always bring a shovel) A GM counter is only of value once back at the motel to figure out what to send home or toss out the next day at the next mine.

I attach two images of how to U hunt with a scintillator. Note my backpack which had a number of hot specimens in it, located right at my spine, a blood forming organ, soaking up the Beta and Gamma rays.

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At the Home Stake mine, I scan with my TSA scintillator.  Beautiful vista from the mine in late Ocotber 2009
At the Home Stake mine, I scan with my TSA scintillator. Beautiful vista from the mine in late Ocotber 2009
My pal Bill Kolb digs for a rich chunk of U rock after my scintillator sniffed it out.
My pal Bill Kolb digs for a rich chunk of U rock after my scintillator sniffed it out.
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: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

Nice application of strings there. I plan on a solid handle for the scintillator in the vein of my Geigerstik. With the ratemeter in a pocket of the backpack and headphones on.

BTW this is the Geigerstik.
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Re: Neutron Scintillation Tube/Counter

Post by Bruce Meagher »

Dennis, Wrong person. I still have plans to do pulse shape descriminatiin with some of my bc-412 stockpile. Unfortunately, I have many plans, each one moving forward at a glacially slow pace.

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Re: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

LOL; oh, missed that! Didn't realize the relevance, there, Bruce! Thanks for pointing that one out!

Slow is fine - I built up required supplies/equipment for my scintillation effort for over a year. Like the self contained counter I acquired for another project, I will now have a use for that after all since I now have such a selection of tubes for the old analog GM unit; or my lead bricks (for yet another project), here again, I might have a use for them shielding the scintillation counter. Cosmic showers or no ... well, the corollary for that saying doesn't work here.
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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

LOL @slow. Look at my forum registration date. That was about 1 year after I had started making plans for a fusor and began gathering parts. :)
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Re: Neutron Scintillation Tube/Counter

Post by Richard Hull »

I was the slowest of all here. Starting the effort in 1997 with no internet content related to amateur fusion, I built a demo fusor in about 4 months, but I had all the fixin's on hand. I didn't have to purchase a thing, but I soon would start what has become about a $10,000+ spending spree over the last 19 years in the fusion quest. I will also note that it took 7 long years to get a plus-ultra- neutron counter and 4 years to get, (make), a suitable mega-mark, fusor power supply.

I worked the demo fusor II for 2 years, reading cover-to-cover over 4 volumes on gaseous conduction. Then came the Farnsworth TV site on "songs.com" put up by the perfesser. When Paul found out, during his research, that Farnsworth had pursued fusion, he added a path on his songs/Farnsowrth site to see if there was an interest in Farnsworth's fusion effort. This effort on Paul's part was an immediate success! My first fusion was in fusor III which never exceeded 150,000 n/s. What I consider my real full blown fusor IV came in 2004. All of this was after the demise of "songs.com" and the passing of our "intranets" fusor site and the founding of this site in 2002. I have threatened over the last 10 years to make fusor V, but hey....slow is slow, and slow continues.

I love history. The history of this amateur effort is long and interesting. If you would like to see where it all began, check out the archived Songs postings to see how little we knew and see some names still around today, way back when.

https://fusor.net/old-boards/songs.com/

Note: the first post at the top is actually the last post in 2000 scrolling down will take you to the first postings.

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Re: Neutron Scintillation Tube/Counter

Post by Silviu Tamasdan »

We're getting nostalgic now, but that old board (which I wasn't a part of) is an interesting view in the past. Thank you for posting that.
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Re: Neutron Scintillation Tube/Counter

Post by Richard Hull »

Yes we had stars in our eyes then and thought all fusion came from hard deuteron collisions in the poissor within the inner grid. Innocence has been lost over the many years. Without quantification but with a lot of good qualification we now know much more about when, where and how fusion is done in the simple fusor. The verve and willingness to pursue amateur fusion remains unabated.

I had a blast re-reading a large fraction of those early postings over the last few days. I am glad to have resupplied the URL so others could take a trip down memory lane when this entire subject was new and vital.

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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: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

An update and notes for my effort to start up my neutron detector systems again under this thread: the previous weekend, my home built scintillation tube/power supply caused the ST-360's counter's diode voltage clamp to fail yet again. Oh well, microscope level soldering again. I realized my current system just isn't good enough - both the voltage control and interface system.

So I started deciding how to improve the system. That is when I realized that I have in storage an EC-650 "Gel-cell" power supply; this has a digital read out and complex feed-back control to provide any voltage from 0-6000 VDC (+/-) output (up to 100 ma.) While the unit is very stable (unit weights a good 40 lbs, however) I noticed that it did vary a few volts every now and again - apparently line variation in my home; so I added a line conditioner. The unit is now rock steady. So, I will use this both for my Russian neutron tubes and my scintillation tubes as a voltage source.

To enable this system to operate these tubes and my counter safely, I built a new and better interface box. This box has three co-axial connector outputs - one for the high voltage (HV) input, a second connector for the detector line and the third for the signal output from the detector to the counter/pre-amp (ST-360.)

Internally for this interface box I have a removable resistor (currently about 10K-ohms) for the voltage draw down on the signal output side of the cap that is used to both prevent HV from the counter and provides the data input to this counter. This cap/resistor feeds the output connector to the ST-360. The connector for the detector tubes has a 100 M-ohm resistor in-line and that resistor then connects to the other side of the capacitor (the HV side); and these, in turn, are connected to the high voltage input coaxial connector from my EC-650. Finally, I have a 1000:1 resistor bridge hookup inside to enable me to monitor voltage independent of what the EC-650 displays (these have 'banana type plug' connectors on the box.)

This system appears to provide a very stable voltage and enables both a proper resistance for the detector input voltage along with a safe signal connector for my ST-360 (the cap should block the HV but pass the signal.) I guess I will need an oscilloscope to determine the optimum resistor for the cap (however, I am using the value suggested in the paper for russian tubes.)

Until I repair the ST-360, I will experiment this weekend with a pre-amp system I have and a digital counter in order to test if I can get this power supply/interface system to work with a simple Geiger Tube. Once I am confident of its operation, I can repair the ST-360 and maybe try that and this new system with my He-3 tube.
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Dennis P Brown
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Real name: Dennis Brown

Re: Neutron Scintillation Tube/Counter

Post by Dennis P Brown »

After re-reading Rex Allens' excellent and detailed comment on Silvio Tamasdan thread "Criticize my Neutron Detector Setup" I realize that I am making a few fundamental mistakes in my interface box - the primary issue being the capacitance of my co-axial cable between the signal cap and the detector tube. I am referencing the thread and in Rex's post his second diagram showing the co-axial cable connection to the detector tube: viewtopic.php?f=13&t=11954&start=10

It would appear from his post that I should enclose my neutron detector tube within the interface box and directly connect the 'buffer' or signal capacitor directly to the tube so that part of my circuit has no significant capacitance of its own (between this buffer cap and the tube); then, run the HV to this via a short co-axial cable thru my 100 M-ohm resistor in the box and then use this to power the detector (see the first drawing of that post by Rex.)

I do have room in the box to add a pre-amp but that depends on powering such a device. I will consider that in a later mod of the system. For now, I will most likely continue to use a long coaxial cable to output the signal from the 'buffer' capacitor to my counter system.
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