Search found 2329 matches

by Carl Willis
Thu Oct 30, 2014 10:13 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Nuclear measurements on Chicago Pile artifact
Replies: 11
Views: 5499

Re: Nuclear measurements on Chicago Pile artifact

Hi Andrew, The UNM NE guys have been doing just fine by the looks of it, and they kindly let me use their HPGe for this experiment. I have my own, but there's not really a purpose to buying 30 liters of LN2 just to measure one thing like this. I set up a tour of their little 5-watt AGN reactor for T...
by Carl Willis
Thu Oct 30, 2014 8:07 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Nuclear measurements on Chicago Pile artifact
Replies: 11
Views: 5499

Nuclear measurements on Chicago Pile artifact

Hello Fusioneers. I have been away from the board for a while, professionally occupied and otherwise having not much to say here. And I am sorry to have missed the last HEAS; that wasn't my intention, but work obligations had to prevail. I don't know if my admin-status banhammer is still functional:...
by Carl Willis
Thu Apr 03, 2014 1:15 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: spherical fusor construction
Replies: 6
Views: 2881

Re: spherical fusor construction

The flanges you are looking at have been used by many other builders in conjunction with 6" architectural hemispheres. The only question for you is whether MDC has the best deal, since virtually every vacuum supply house carries this flange. You might compare with -Kurt J. Lesker -Duniway Stockroom ...
by Carl Willis
Tue Apr 01, 2014 10:17 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Scintillation counter dose readout
Replies: 11
Views: 4219

Re: Scintillation counter dose readout

Hi Pete, Dosimetric quantities can be challenging to measure with a scintillator for two reasons. The first is basic physics: radiation interacts differently with the substances in scintillators and the substances that make up biological tissues, and certain simplifying assumptions that can be used ...
by Carl Willis
Fri Feb 14, 2014 3:36 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: X-ray machine power supply question
Replies: 2
Views: 2122

Re: X-ray machine power supply question

Hi Mark, Your question is an important one, as x-ray machines are rated for short-term current delivery at very low duty cycle. This is almost certainly a 60-Hz transformer-based machine. It should be able to handle a few milliamps continuously, and will run cooler if the voltage is reduced (due to ...
by Carl Willis
Wed Feb 12, 2014 12:33 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Videoing fusion
Replies: 3
Views: 2080

Re: Videoing fusion

Radiation is not a significant concern for your camera's sensor. Not from hobby fusion, anyway. X-rays are detected rather efficiently by both CMOS and CCD sensors, creating sometimes overwhelming noise in the image without appreciably damaging the sensor. If you want to shoot video through a viewpo...
by Carl Willis
Tue Feb 11, 2014 6:56 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Safety
Replies: 3
Views: 2658

Re: Safety

Electrical safety is the most important safety issue with a fusor, and the only issue that presents a substantial and immediate threat to life. If you come into the fusion hobby having no prior high voltage background, be sure you work with guidance from an appropriately-experienced mentor. The best...
by Carl Willis
Thu Jan 23, 2014 6:15 am
Forum: Vacuum Technology (& FAQs)
Topic: Thermocouple gauge
Replies: 15
Views: 4879

Re: Thermocouple gauge

A DV-6M tube (or off-brand equivalent from Lesker, Duniway, LDS, etc.) will work only with the Hastings controller made specifically FOR THAT TUBE (or off-brand equivalent). Same applies to the Varian 531. The gauge faces say what tube they will work with on the front. If a controller is offered up ...
by Carl Willis
Wed Jan 22, 2014 9:59 pm
Forum: Vacuum Technology (& FAQs)
Topic: Thermocouple gauge
Replies: 15
Views: 4879

Re: Thermocouple gauge

A TC gauge tube must be used with a controller designed for that specific type. Using a mismatched controller with a tube will result in incorrect readings at best, and possibly a damaged tube. Luckily, the common types mentioned earlier are very popular, and on any given day, eBay will have multipl...
by Carl Willis
Wed Jan 22, 2014 6:32 am
Forum: Vacuum Technology (& FAQs)
Topic: Thermocouple gauge
Replies: 15
Views: 4879

Re: Thermocouple gauge

For best price and function in a TC gauge, go with a brand-new Hastings DV-6M or equivalent (e.g. 6000 series from LDS or Lesker). The Varian 531 is also popular and inexpensive, but has inferior sensitivity in the micron range. The gauge tubes are $40-50 new with the typical 1/8" NPT fitting. Used ...