NEW Fusor V build under way.

For posts specifically relating to fusor design, construction, and operation.
User avatar
Mark Rowley
Posts: 909
Joined: Sun Dec 29, 2002 12:20 am
Real name: Mark Rowley
Location: Sacramento California
Contact:

Re: NEW Fusor V build under way.

Post by Mark Rowley »

Lookin great Richard!
What’s your rough TIER guesstimate at the 68kcpm number?

Mark Rowley
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

With fusor IV and the calibrated water moderator detection system, the 68k count would have been 1,300,000 TIER, but this moderator is far more efficient and I would guesstimate around 800,000 TIER. My guesstimate would be on the order of value as a poke in the eye with a sharp stick. Hey, you asked.

The reason is that even my activation based data figured on the old calibrated efforts fall flat. Why? Because I am getting instant counts on the silver with my new system which rival the best I ever did at the mega TIER range due to the loss of short lived activation product numbers in my 10 second dash to the old NIM counter which counted only for a full minute to give a number. Apples and oranges..........

One must be very careful not only in calibration, but in all neutron measurement processes that are claimed to be solidly backed. I can only back the neutron counts in my detector and the counts in the instant activation counter I have just assembled. They are real, but say little about the TIER. I just changed too many processes with fusor V.

The result is another source of calibrated neutron reading is needed. Soon, I hope.

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
User avatar
Mark Rowley
Posts: 909
Joined: Sun Dec 29, 2002 12:20 am
Real name: Mark Rowley
Location: Sacramento California
Contact:

Re: NEW Fusor V build under way.

Post by Mark Rowley »

Based on those numbers your 3He tube is just about twice as efficient as a SNM11 boron tube.

Mark Rowley
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

3He is the best and #1, boron is a close #2. Boron tubes are rarely at even 1 ATM! Most all 3He tubes are at 3 or 4 ATM. I do have a huge 2" diameter BF3 tube that is 24 inches long here that is at 70cm pressure. So make a Boron tube big and you get better counts. A good boron lined tube is #3 but is tough to bias in amateur hands with no neutron source.

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
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

New record count and activation of short lived Silver activation product to above 6X background 8/12/20

Best run 12 microns, 42kV, 20ma, 78,180 CPM. Thermal heating of chamber still a limiting factor.

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
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

Finally I have it down pat! The secret is to leap on this horse and ride it hard as hell before it over heats. It can take it, too! Today another record run at the monthly HEAS meeting. I had a member stop watch me.

From dead off system with the fusor V chamber near atmosphere, to chamber down to submicron with turbo. T0 to T=2.5 minutes.
Deuterium Gas immediately set to 12 microns and producing 57,973 counts/min T=2.5 to T=4.5 minutes.
Continuous operation until total shutdown at T=10.3 minutes with a final 1 minute count of 85,189 CPM at the following specs..... 12.6 microns, 44.5 kV, 16 ma (final chamber temp 71 deg C.)
Immediately, within 2 seconds, pressed the count button on the embedded GM silver activation counter. Fast activation product just over 8X background.
Very happy with this speed racer system. I have found that once the chamber hits 100 deg C the returns are highly muted with lots of pressure bumps and diminishing returns are the norm. Can't explain the bumps of 3-4 micron oscillations.

I have possibly figured a crude and less than satisfying way to back calibrate the system. I have 13, more or less calibrated neutron producing years recorded in my large fusor IV notebook. Without involving counts on the neutrons counters, per se, but using only the activation results versus the new activation results, I should be able to find a three value known items with TIER values to find the fourth value (current equivalent neutron count relative to the old activation counts. Find similar pressures, voltages and currents to activate to a similar current set of those variables. Using this info., the TIER's should have some similarity but I will have to take the new volumes of the current moderator to the old neutron oven and the loss of silver counts due to the run to the old NIM system. I hope every one got that and realizes just what a stretch and how many records I have to sift through and guesstimates needed on the moderator differentials and lost counts on the old silver runs. Still, it is a link of sorts until I can do better on active calibration.

Then again, am I just floating fluff with possible net results showing I am doing 10,000 TIER or 3.9 million TIER?? Neither are even close, of course, but if I do all the data mining, calculations and guesstimates, then come up with something ridiculous like the aforementioned numbers, what a wheel spin! The confidence level would be crap, I am sure.

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
User avatar
Bob Reite
Posts: 576
Joined: Sun Aug 25, 2013 9:03 pm
Real name: Bob Reite
Location: Wilkes Barre/Scranton area

Re: NEW Fusor V build under way.

Post by Bob Reite »

I thought that you had a calibrated REM ball setup. If not, and nothing better comes up, I'm planning to bring my REM Ball down for the October meeting.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

I had my PNC-1 calibrated, not my remball system. I tried using it, but for some reason it is non-functional after being in storage since I got it back! I did not think to test it figuring it was aces. Oh well.
I am curious, is your remball a log-lin system by Eberline? That is what mine is and many neutron metrolgists I know have said the electronics in the PNR-4 are a nightmare to keep stable and in calibration. The PNR-4 has two meter needles in its meter that sweep like windshield wipers and does not have a range switch. Mine has been in storage now for 10 years!!

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
User avatar
Bob Reite
Posts: 576
Joined: Sun Aug 25, 2013 9:03 pm
Real name: Bob Reite
Location: Wilkes Barre/Scranton area

Re: NEW Fusor V build under way.

Post by Bob Reite »

Mine is the Eberline SRM-200 "Smart Radiation Monitor". Many different ways to configure it for different detectors other than the BF3 tube used in the REM Ball. I made sure that I could get a manual with schematic and that it was being sold with a money back guarantee if the microprocessor (although one might be able to find an Intel 80C31 on Ebay) or EPROM proved to be defective.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

Bob, If your remball works, pack it along when you come as it will be most welcome, for those with a good bubble dosimeter who might attend the big HEAS gathering, bring it along, as well. Due to the close confines in my lab, I will only allow 5 people in at a time to view the working fusor V so that social distancing can be observed. Those with instruments get first pass invitations. Note the x-rays at full tilt with my lead shield in place are about 1mrem/hr at a range of two feet from the reactor. At the normal visitor viewing range it is under 0.2mrem/hr.

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
User avatar
Bob Reite
Posts: 576
Joined: Sun Aug 25, 2013 9:03 pm
Real name: Bob Reite
Location: Wilkes Barre/Scranton area

Re: NEW Fusor V build under way.

Post by Bob Reite »

I'm using the REM Ball these days exclusively when I operate my fusor as I trust the calibration and I don't have an infinite budget to buy bubble detectors every six to nine months.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

Another great Silver activation day and high point in the new fusor V saga. The system secret is speed and playing "beat the temperature clock". I ran the system for a total of 20 minutes today from dead off to highest activation level and with numbers not yet seen in fusor V. The data is in the enclosed captured Xcel graph. (98,288 CPM)! Images are captioned.

Note: four background runs of 10 minutes each yields 240 data points indicated a mean count of 13 and a sigma of 3.6. Still, to my mind, it is not a great statistical result to hang one's hat on. ( very gamma noisy lab) The detector will not count gammas....Maybe 1 in 200. It is detecting, as I have noted, photo electrons and some limited Compton electron scattering from the extant gamma field, impinging on the silver and tube walls

Addendum: In the wee hours of the 22nd, I went out and activated again. The new graph shows far greater activation due to similar neutron numbers, but I placed a single layer thickness .003" roll or cylinder of silver around the tube as a silver tubulation over its sensitive volume. (much better)

Richard Hull
Attachments
Final CPM count at the end of activation - fusor shut down
Final CPM count at the end of activation - fusor shut down
Final temperature of the fusor chamber at shutdown 90 deg C
Final temperature of the fusor chamber at shutdown 90 deg C
Graph and activation data in title give all info.  I added significant points
Graph and activation data in title give all info. I added significant points
New graph taken 12 hours later but with 9999 silver sleeve over GM detector tube
New graph taken 12 hours later but with 9999 silver sleeve over GM detector tube
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
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

As I continue to run fusor V every day or every other day, my viewport is virtually opaque to visible light. NO color. NO central star. Only the IR seen from the glowing grid is seen on the monitor.

I have about 4 other replacement viewports. I wonder if it is worth replacing it for the HEAS October crowd? If I open the fusor it will take a week of daily runs to work it back to superior operation. I assume everyone has seen the pretty color stars, etc., and a clean color image is of no great interest. What I will show is the silver activation and post-run count as well as creating an excel graph as all watch who are interested.

I am also considering removing my 23 inch long 3He tube and replacing it with a 12" active length 4ATM Reuter-Stokes, 3He tube. I have the cps/nv manufacturer figure for this tube and it is 40. this reduction will make for a lower count per run, but allow for less possibility of pile-up and for more flux if I can get there. It should also be more suited to the moderator that I have and, in all probability, indicate the same flux under the same max conditions as the big tube. (lower count and lower counting efficiency means the same flux) I will probably do this after HEAS.

I am also going to mount that 5" BC720 on the PMT. In theory the count from this proton recoil counter should be 5% or even less than any 3He count at ~0.1% count efficiency. I will probably calibrate this system using the well calculated 3He data collected co-jointly on several fusor V runs.

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
User avatar
Bob Reite
Posts: 576
Joined: Sun Aug 25, 2013 9:03 pm
Real name: Bob Reite
Location: Wilkes Barre/Scranton area

Re: NEW Fusor V build under way.

Post by Bob Reite »

That's the viewport from Fusor IV correct? Must have a lot of hours on it. Mine is getting a bit hard to see through, I have a couple of new ones, I originally bought them on Ebay as a "must take all three" deal.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

No! Actually it has only been in use as a brand new window as of the first post in this thread, 7/10/20.
Look at the colorful, full image in the post of 7/11. I have been driving this iteration very hard. Again, only the fact that the video camera is sensitive in the IR that I see only the snow white, heated grid, floating in a totally ink black void.

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
User avatar
Bob Reite
Posts: 576
Joined: Sun Aug 25, 2013 9:03 pm
Real name: Bob Reite
Location: Wilkes Barre/Scranton area

Re: NEW Fusor V build under way.

Post by Bob Reite »

The IR totally overwhelms the camera. I snapped my photo by turning off the HV, just long enough for the grid to cool, then starting it up and snapping the photo before the grid had a chance to heat up again.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

The window is 100% opaque to any visible light whatsoever, period! It might as well be made of stainless steel. It is not a #10 density filter it is worse than that. Intense IR is all that will penetrate. A the windo is of no real use, I will leave this sleeping dog lie until after the HEAS gathering. All who attend will see what I mean. I will then swap the window out after HEAS.

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
User avatar
Bob Reite
Posts: 576
Joined: Sun Aug 25, 2013 9:03 pm
Real name: Bob Reite
Location: Wilkes Barre/Scranton area

Re: NEW Fusor V build under way.

Post by Bob Reite »

I'll have to see it for myself. Hard to believe that you turned the window black in such a short time. Maybe your grid is closer to the window than my setup.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

Another record run today. I attached the image of silver activation graph.
I hit 120,736 cpm on the counter. This results in a TIER of 137,000 n/s

The grid is 1 inch in diameter in the center of a 6" diameter sphere. window is offset from the sphere by .75 inches. This makes the outside grid wire nearest the window 3.25-inches from the glass.
I plan on detailed runs for all fusioneers attending HEAS in a week or so. Now I can start from nothing on to finished activation in under 30 minutes.

Richard Hull
Attachments
Neutron Activation AG 9-23-20.JPG
Neutron Activation AG 9-23-20.JPG (91.08 KiB) Viewed 7554 times
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
User avatar
Jim Kovalchick
Posts: 717
Joined: Wed Apr 13, 2011 8:00 pm
Real name:

Re: NEW Fusor V build under way.

Post by Jim Kovalchick »

That TIER number seems low for the good activation you are doing.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

True, it does but that is what I get from the data sheet for the 3He tube I am using. I did an update on calculating this in the FAQ on Calibrating neutron counters just a few days ago. You should have seen it. It is near the end of the pdf. It begins at the addendum.


Richard Hull
Attachments
Calibration of neutron counters.pdf
(189.25 KiB) Downloaded 231 times
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
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

I made some really bad assumptions related to the counting efficiency 59 cps/nv from 63cps/nv. I was also off on the average distance from the 3He tube to the net source of neutrons, from 18cm to corrected to 24cm. These adjustments considerably corrected the TIER and my constant of multiplication. The TIER is not 137,000 n/s, but is now 248,717 n/s. Likewise the multiplication factor is no longer 1.135 but is now 2.06 times the cpm rate.

Thanks Jim for pushing me to really question my numbers. I can do a detailed presentation at HEAS on the large white board as to the adjustments.

All the PDF files are now fully corrected. You might reload them if you want the math corrections. They are the same, so just reload the original post's PDF.

Always refining by closer examination of the parameters.

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
User avatar
Bob Reite
Posts: 576
Joined: Sun Aug 25, 2013 9:03 pm
Real name: Bob Reite
Location: Wilkes Barre/Scranton area

Re: NEW Fusor V build under way.

Post by Bob Reite »

I really didn't think that you could successfully activate silver with only 137, 000 n/s. 248,717 is more realistic, but I still thought that you had to be near the mega mark to do activation.
The more reactive the materials, the more spectacular the failures.
The testing isn't over until the prototype is destroyed.
User avatar
Aidan_Roy
Posts: 80
Joined: Wed Jan 01, 2020 10:08 am
Real name: Aidan Roy
Location: Massachusetts

Re: NEW Fusor V build under way.

Post by Aidan_Roy »

Richard,

I think a detailed view of your TIER calculation adjustment at HEAS would be great, definitely something I would enjoy to see.

Aidan
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: NEW Fusor V build under way.

Post by Richard Hull »

You will see the complete derivation update on my white board. I put it up today and ran through a verbal explanation for practice to an empty lab. Talking to myself again....tsk...tsk.

Unfortunately, on rechecking the cps/nv on the spec sheet, the figure of 63 is given with the stated accuracy of +/-20%?! So, it could be either 198640 or 297360 or anywhere in between the computed 248,717n/s.
It is to be remembered that a 3He tube is a proportional counter and once out of the manufacturers hands, it can be biased anywhere from 1500-2000 volts and be in spec, this can affect pulse height and the proportional slope. In addition, the windowing can benefit or limit the neutron count. I think they took this into consideration.

I am going to pull out the digital o'scope and tune this thing up a bit from the preamp on to the main amp. Again, and this has been said by me many times.... There is no absolute neutron counting system. There is absolute precision to 1% or better in a fixed neutron counting system to relative quantitative improvement or degradation between runs.

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
Post Reply

Return to “Fusor Construction & Operation (& FAQs)”