Neutron Club Application - Mark Rowley

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Mark Rowley
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Neutron Club Application - Mark Rowley

Post by Mark Rowley » Mon Jul 22, 2019 12:03 am

After an unprecedented amount of free time over the past couple weeks, I think I may have made enough progress to humbly submit my first set of results for Neutron Club membership.

I joined the Fusor forums in 2002 and was active for a few years making demo Fusors and experimenting with a multitude of grid shapes. Due to being a fairly new dad back then, in addition to career and finances it was impossible to get beyond that point. But that was ok as I enjoyed reading the forums as much as wrenching on a project. During all those years and up to now, I want to extend my gratitude to Richard Hull, Frank Sanns, Steven Sesslemann, Carl Willis, Scott Moroch, Tim Koeth, Eric Smith, Jake Hecla, Robert Tubbs, and everyone else for their expert advice and willingness to help. It’s been a fun journey so far and no doubt it will continue for many more years.

Vacuum Chamber Arrangement
My Fusor is a small 2.75” four way cross with a T attachment to support the DV-6M thermocouple gauge. Vacuum is achieved with a Varian HS-2 diffusion pump backed by a Ritchie Yellow Jacket 6cfm roughing pump. The diffusion pump is cooled by a small pond pump which cycles cool water through the cooling coils. The diffusion pump is throttled by a standard gate valve. This will be upgraded in the near future. The two loop grid is made from tungsten and measures 0.50” in diameter. The HV feedthru is one of Richard’s designs from years back. If I’m not mistaken, I purchased the beryllium insulator from him sometime between 2002-2004. Deuterium flow is metered in with an SS-SS4 needle valve which connects to the left side of the chamber.

Power Supply
At first I attempted to use two vintage Hammond XRT’s from 40yr old dental equipment but unfortunately neither was up to the task. Neither lasted longer than a couple of minutes. So after perusing the site for more ideas, I came upon the Precipitator Power Supply. Specifically, the 10ma / 30kV version profiled by Finn Hammer a year or so ago. After hooking it up, I was nothing short of amazed by its performance! There was no over-current shutdown issues and as Finn said, it loafs along at full tilt without a problem. I highly recommend others to purchase and experiment with this as it opens the doors of affordability and accessibility to those who stall because of no fusion-capable power supply. Within a week I will be testing the larger 4 transformer 10ma / 60kv supply.

Electrical Metering
Voltage: Analog meter with 100 meg 50kv resistor
mA : DVM as indicated in the FAQ diagram

Neutron Detection
Ludlum 2221 Ratemeter
CHM14 corona tube biased at 670v
6” Diameter / 10” tall paraffin cylinder as a moderator
Normal Background count, 1cpm average

xRay Detection
Eberline E120 with an HP-260 pancake probe
GammaGuard CT007-N CsI(TI) digital scintillator

Deuterium
Horizon Mini PEM Cell
United Nuclear D2O
100mL syringe as a container

Neutron Run / Report
During the run I was able to maintain the following conditions:
VOLTAGE: 21kV
AMPERAGE: 1.8-2.2 mA
DEUTERIUM PRESSURE: 40 mTorr

Prior to the run, I totally evacuated the chamber to less than 1 mTorr. Afterwards, I raised the pressure to almost 100mTorr with Deuterium and then throttled everything down to a stable 40mTorr. At just over 15kV and 1.2mA, counts began to register on the scaler. Being a new system (and operator), I was reluctant to push it beyond 21kV at ~2.0 ma (for this run) however this will change now that I’m gaining experience with the arrangement.

I conducted five individual 1 minute moderator / no moderator assessments. The distance from the chamber to the detection tube was approx 8". The following are the results of those runs:

#1
Moderator: 17cpm
No Moderator: 1cpm

#2
Moderator: 19cpm
No Moderator: 2cpm

#3
Moderator: 21cpm
No Moderator: 1

#4
Moderator: 27cpm
No Moderator: 1

#5
Moderator: 26cpm
No Moderator: 2cpm

The following videos are an overview of my system and a demonstration showing the difference between the CPM with moderator and no moderator.

https://www.youtube.com/watch?v=SlHoUIE ... e=youtu.be
https://www.youtube.com/watch?v=hsKuUIg ... e=youtu.be

The following pictures are of the deuterium plasma, the Fusor, power supply, and PEM cell arrangement.

I am looking forward to improving my system, increasing my numbers, and testing the next power supply. If there are any questions please feel free to ask.

Mark Rowley
Attachments
System 1.jpg
Power Supply 1.jpg
PEM Cell.jpg
D2 Plasma Star.jpg

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Mark Rowley
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Re: Neutron Club Application - Mark Rowley

Post by Mark Rowley » Mon Jul 22, 2019 2:43 am

Here’s the latest run at 30kV / 2.92ma / 30mTorr of deuterium pressure. In this video the count rate is much higher and drops to negligible levels when removed from the paraffin moderator.

https://youtu.be/MFOrEsPDrZw

Mark Rowley

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Richard Hull
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Re: Neutron Club Application - Mark Rowley

Post by Richard Hull » Mon Jul 22, 2019 6:10 am

Mark fabulous printed report with all the data in your original post above!. The ultimate clincher is this last video run at 30kv above.

This effort was so well executed and documented in the last video that all must see this video and how you proved fusion in the most elegant fashion. This method is the often requested manner as proof positive if your only capability is electronic detection. This test is the real electronic test regardless of whether you sport a Russian corona tube , Boron lined tube, BF3 tube, of 3He tube.

Here is my hurrah highlight of the video and the wonderfully ordered steps you took in making it.

1.You showed your overall setup in a flowing, no cut video.
2.You showed the instruments and their readings...30kv, current, and pressure
3. While doing the above we could hear your audible increased clicks as you panned from the instruments to you detection tube in moderator on to the digital rate meter count.
4.Without any cutaway, you drifted back to the moderator, removed the detector tube and put it even closer to the fusor in the flask, we heard the count drop almost completely away.
5.You continued the left most movement to verify that you were still at full power 30kv, current and pressure
6.Walking back to the right again you picked up the tube and put it back in the moderator and the counts immediately went up again.

It can't get any better than this video exposition of your work. No narration needed, just a good pair of eyes from those of us who have done fusion in the past. The extra 10kv from 20kv to 30kv was what you needed to really impress both the viewer and your counter rate meter.

I have saved the URL of your last video to use as the shortest and most complete proof that the fusor's progenitor has done and is doing fusion.
Your time spent since 2002 shows that you have worked the "hands-on imperative"', the self-directed learning angle and the have the verve to keep at it to a fabulous win. This is the best video proof I have seen to date. I welcome you to the neutron club.

You are correct, now that you know how to work the system it will be easy to push it further. With each new run, your ability in the artifice of squeezing the last neutron out of you system will become apparent.

Fabulous, fabulous, fabulous!!

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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Re: Neutron Club Application - Mark Rowley

Post by Joe Gayo » Mon Jul 22, 2019 3:23 pm

@Mark - Just for completeness, you are running the SNM-14 tube (http://www.sovtube.com/x-ray-and-geiger ... nm-14.html) below the corona region which does remove the corona noise but may present a gamma rejection problem at higher voltages.

This seems to recommend 900-1000V - https://inis.iaea.org/collection/NCLCol ... df?r=1&r=1
Last edited by Joe Gayo on Mon Jul 22, 2019 4:10 pm, edited 1 time in total.

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Dennis P Brown
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Re: Neutron Club Application - Mark Rowley

Post by Dennis P Brown » Mon Jul 22, 2019 3:46 pm

Extremely impressive - besides a great vid you generated your own deuterium gas and used a novel power supply (the one we have all wondered about - really answered that question!); these are two issues that stop so many projects. Overcoming these two problems and the detector is really quite an accomplishment. Your setup should be carefully examined by any person desiring to do fusion. The fact you used a 2.75 "Tee" for your fusor "chamber" also further demonstrates that developments potential as well. You have made a gold standard for a setup! :)

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Mark Rowley
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Re: Neutron Club Application - Mark Rowley

Post by Mark Rowley » Mon Jul 22, 2019 5:32 pm

Thankyou Richard for the nice words and my inclusion to the club. I really owe a lot to everyone here for their expert advice. Without it I highly doubt I would've made it to this point.

Joe, thanks for the links on the CHM14 tube. I'll add more detail to my earlier post in the Neutron Detection section.

Thanks Dennis. I cant say enough about the success of the precipitator supply. Later this evening I'll start a new post about it in the Input Power section. Regarding the T section, I added that to the 4-way (which is the main chamber) as a place to mount the thermocouple. Since everything is so close together in a 2.75, I wanted the TC port out of line from any possible electron beam.

Mark Rowley

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Re: Neutron Club Application - Mark Rowley

Post by Richard Hull » Tue Jul 23, 2019 5:39 am

Interestingly, the characteristics of the 2.75 CF cross and its high pressure regime means there is little need for a deep reading vacuum gauge in this type of system. A good, honest reporting TC gauge will suffice..... Assuming you can zero it with a diff or a turbo pump in your system. I use a KF16 right angle fitting to isolate my Baratron capacitive gauge from direct ion/electron beam impact.

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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