Search found 156 matches

by Peter Schmelcher
Thu Nov 28, 2019 9:12 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Fusor construction questions
Replies: 9
Views: 722

Re: Fusor construction questions

You might consider getting a gas dryer that could also double as a reservoir to isolate the cell. Make the gas in a batch and then later run and adjust the fusor and don't think about the gas generation. ebay item number 150382481448 (Supelco # 20619 Molecular Sieve Water Vapor Trap 200 cc).
-Peter
by Peter Schmelcher
Sat Aug 31, 2019 6:11 pm
Forum: FAQs: Neutron - Radiation Detection
Topic: FAQ - Neutron Transport Simulation, Detector Calibration, and Shielding
Replies: 10
Views: 3713

Re: FAQ - Neutron Transport Simulation, Detector Calibration, and Shielding

Nice work!

Another arrow in your quiver could be Cosmic ray generated neutrons. For initial testing, does my detector setup work, it’s a no brainier. For calibration it remains an unanswered question.

Previous post with attached papers.
viewtopic.php?t=11307

-Peter
by Peter Schmelcher
Tue Mar 12, 2019 6:38 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Vaccum Leak Testing / Technique and Power Supply Question
Replies: 18
Views: 8416

Re: Vaccum Leak Testing / Technique and Power Supply Question

I believe the gurgling sound in the video is cavitation in the oil which is normal but only when the gas ballast is open or if you have a large leak. The oil reservoir screw cap probably has an o ring and should be closed when you are trouble shooting the vacuum pump. https://vacaero.com/information...
by Peter Schmelcher
Wed Feb 20, 2019 8:20 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: SNM-11/СНМ-11 Tube - Again ...
Replies: 12
Views: 6362

Re: SNM-11/СНМ-11 Tube - Again ...

I would guess all these Russian tubes were originally intended for Chernobyl. They got stuck in storage for 30 years before finally being considered surplus junk and we got them cheap. Lukas I agree Geiger mode operation seems odd but who knows what was intended 30 years ago. If I was asked to desig...
by Peter Schmelcher
Wed Feb 20, 2019 1:31 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: SNM-11/СНМ-11 Tube - Again ...
Replies: 12
Views: 6362

Re: SNM-11/СНМ-11 Tube - Again ...

Increasing the bias voltage increases the gain of the tube. This change is not linear. At some higher bias voltage the atoms start to behave more like a ring of dominos, knock one over (ionize one atom) and they all fall down (which is Giger operation and I do not use the tube at that voltage). Yes,...
by Peter Schmelcher
Tue Feb 19, 2019 9:06 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: SNM-11/СНМ-11 Tube - Again ...
Replies: 12
Views: 6362

Re: SNM-11/СНМ-11 Tube - Again ...

I did lots of work many years ago with various Russian tubes. I knew a Russian Physics and he graciously translated a detector data sheet for me. The SNM11 / CHM11 tube has a maximum do not exceed voltage of 1600V. The recommended operating voltage is 700V and when detecting thermal neutrons the eff...
by Peter Schmelcher
Thu Jan 10, 2019 11:25 pm
Forum: Fusion --- Past, Present, and Future
Topic: Wendelstein 7-X has successfully finished its second major experimental run
Replies: 27
Views: 20187

Re: Wendelstein 7-X has successfully finished its second major experimental run

Hydrogen isotopes can now be separated from regular hydrogen using a membrane. I can’t remember the original research article read sometime in the last two years but it was a notable American university. I was amazed that a Nano technology membrane could exploit the very subtle atomic differences. h...
by Peter Schmelcher
Fri May 18, 2018 9:17 pm
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: lab electromagnet from scratch
Replies: 61
Views: 40348

Re: lab electromagnet from scratch

I believe you should split the electromagnetic, half around the top and half around the bottom. This should change the magnetic circuit potential in the support arms to zero opposite the air gap, the reduced coil diameter requires less wire so you will get more amp turns from your spool. My fading m...
by Peter Schmelcher
Fri May 04, 2018 8:41 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Spellman DXM70N600X3547 power supplies on ebay -70kV 8.56MA
Replies: 157
Views: 62362

Re: Spellman DXM70N600X3547 power supplies on ebay -70kV 8.56MA

Using Andrews connector autopsy as a starting point I printed a Claymount style HV connector in PLA. It’s a work in progress but basically you cast silicone between a PLA shell and the HV cable to eliminate any air voids between the cable and the shell. The HV connector plug has a 0.5degree taper so...
by Peter Schmelcher
Sat Apr 21, 2018 9:11 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Detector noise problem
Replies: 13
Views: 5548

Re: Detector noise problem

Try disconnecting the HV tube bias supply and cap or short the connection.