Search found 154 matches

by Liam David
Tue Sep 15, 2020 5:43 am
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

I spent some more time in the workshop today and put together a rudimentary MCA for my gamma spectroscopy setup. A Ludlum Model 12 provides the HV and the probe is a custom 85x60mm NaI(Tl) scintillator mated to a Photonis XP5312 9-stage PMT. A 3D printed housing holds everything together. The model ...
by Liam David
Mon Sep 14, 2020 8:13 pm
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

I have an older Ludlum Model 3 (#73001) with a manual that no longer exists on the internet, so I had to do some oscilloscope probing to find a suitable tap point. Pin 3 on the quad NAND gate CD4093BE is pulled high (10v) for 10us for each detection event. To make it TTL and Arduino compatible, I so...
by Liam David
Mon Sep 14, 2020 6:31 am
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

I finally got around to modifying a Ludlum Model 3 to output 5V pulses for each detection event, with the intent of making it a scalar. I tapped one of the schmitt triggers and passed the signal through a BNC connector in the meter face. An Arduino acting as a counter sends each second's total to a ...
by Liam David
Fri Sep 11, 2020 4:19 am
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

Just some pictures of stuff I've been working on. Some problems, things in progress, or needed upgrades: 1. Mass flow controller doesn't like EMI which causes pressure spikes and then cuts off deuterium flow. Obviously not good for stability. Need to rework wiring and shielding. 2. Shielding the DAQ...
by Liam David
Wed Aug 19, 2020 3:20 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: CAD-Based Neutron Transport Simulations
Replies: 0
Views: 278

CAD-Based Neutron Transport Simulations

This is kind of a part 2 to the FAQ I wrote a while back: https://fusor.net/board/viewtopic.php?f=31&t=12906. The first section below is more an archive for my reference than a how-to, so it isn't too detailed. I've been tinkering off and on with the neutron transport code OpenMC over the summer and...
by Liam David
Wed Jul 29, 2020 3:23 am
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

I managed to remove the connector that failed (obviously) but with some undue force. The silicone doesn't stick to the polypropylene as you mentioned, so I'm afraid that the assembly will pull apart. Could probably get the other one out, but it isn't broken so no need to tempt fate. I'll likely keep...
by Liam David
Mon Jul 27, 2020 7:38 pm
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

Yeah, I don't think coils will cut it without exceptional contact and high flow rates. I agree a jacket would be ideal, just not sure how to implement that at the moment. I had one of my 3D printed CA11 connectors (for the Spellman supples) fail a few weeks ago. I was also asked to provide more info...
by Liam David
Sat Jul 25, 2020 4:18 pm
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

Thanks for all the compliments! There is a fan blowing directly onto the chamber which helps by a few degrees, but it's far from enough. It cools stuff down between runs more than anything. I've started thinking about water cooling as well, perhaps some 1/8" copper or aluminum tubing around the arms...
by Liam David
Sat Jul 25, 2020 12:55 am
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Re: Fusor Update - Liam David

IMG_20190925_171532.jpg
Solenoid valve to protect turbos in case of power failure

And some plasma pictures:
by Liam David
Sat Jul 25, 2020 12:50 am
Forum: Images du Jour
Topic: Fusor Update - Liam David
Replies: 18
Views: 1232

Fusor Update - Liam David

I've been working steadily on my fusor for the past several months and have a few noteworthy updates to share. DAQ / Control System I made a new control box that has hardwired connections for voltage, current, and MFC deuterium flow. The signals are passed through 100ft of 15-core, stranded, shielde...