Search found 1031 matches

by Rich Feldman
Mon Jan 21, 2019 6:42 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Integrated Lab Measuring and Controlling (Labview, Labjack, ...)
Replies: 36
Views: 1071

Re: Integrated Lab Measuring and Controlling (Labview, Labjack, ...)

Harald, it sounds like your time sync question is about matching the starting times. Do you, or other readers, also care about finely matching the time scale factors? What sort of time accuracy do the low cost instruments come with? Each instrument in a setup has a different reference for what appea...
by Rich Feldman
Sun Jan 20, 2019 5:29 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Integrated Lab Measuring and Controlling (Labview, Labjack, ...)
Replies: 36
Views: 1071

Re: Integrated Lab Measuring and Controlling (Labview, Labjack, ...)

It gets easier when you have deep pockets. At work I sometimes use a late-model 30+ GHz oscilloscope without setting foot in the lab. It cost more than I make in a year. It's got an Ethernet cable connection. Remotely log in from this computer to the oscilloscope's Windows PC, after sometimes asking...
by Rich Feldman
Sun Jan 20, 2019 5:01 pm
Forum: Announcements and Site Administration Topics
Topic: Straw Poll / Proposal for San Francisco Area mini-meetup
Replies: 21
Views: 1282

Re: Straw Poll / Proposal for San Francisco Area mini-meetup

Continuing on bulletin board, though we have each others' email addresses. Rex & Samuel, I'd rather not meet on 1/26 if intrepid leader Ian can't attend. Maybe midweek, Jan 29-30-31, when Joe's in town. I bet Samuel has school those days. Joe PM ! Following Saturdays I could mostly keep clear, if we...
by Rich Feldman
Sat Jan 19, 2019 1:38 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: HV Divider
Replies: 8
Views: 762

Re: HV Divider

Just got a minor disappointment about resistor working voltage ratings, while making a proportional counter tube bias supply. This started with a 0-100 microamp meter, whose scale card is now marked for 0-3000 volts. kolo2.JPG So the external resistance needs to be 30 megohms. I made it out of ten 3...
by Rich Feldman
Mon Jan 14, 2019 5:05 am
Forum: New User Chat Area
Topic: Rules for Claiming Fusion Clarification
Replies: 10
Views: 588

Re: Rules for Claiming Fusion Clarification

The check list used to include a picture of the maker with the fusor.
I guess that rule was dropped some time around 2016. Anybody remember why?
by Rich Feldman
Fri Jan 11, 2019 2:33 am
Forum: Fusion --- Past, Present, and Future
Topic: Wendelstein 7-X has successfully finished its second major experimental run
Replies: 27
Views: 1998

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

Re. separation of isotopes. It'd be nice to see the numbers for heavy water next to those for uranium enrichment They might represent two extremes of difficulty, among industrialized separation processes. In between are isotope products with special boron, nitrogen, oxygen, silicon, etc. Dennis's po...
by Rich Feldman
Thu Jan 10, 2019 5:15 pm
Forum: The Trading Post
Topic: End of HSC (Halted Specialties) electronics surplus store in Santa Clara, CA
Replies: 2
Views: 289

End of HSC (Halted Specialties) electronics surplus store in Santa Clara, CA

Yesterday I stopped in at HSC, knowing that the owners had decided to close it down. Signs announced that Saturday, January 12, is the last day of business for the retail store. Hours still 8 to 7 M-F, 9 to 5 Saturday. http://www.halted.com Inventory on the shelves looked a little bit depleted. Clos...
by Rich Feldman
Thu Jan 10, 2019 2:09 am
Forum: Fusion --- Past, Present, and Future
Topic: Wendelstein 7-X has successfully finished its second major experimental run
Replies: 27
Views: 1998

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

... fusion has only two advantages if working perfectly. 1. it can be immediately shut down....Can't blow up ... To clarify that point: Nuclear fission reactors maintain a chain reaction at the edge of criticality, 24/7/365, but they have not been known to blow up. Chain reaction can be terminated ...
by Rich Feldman
Wed Jan 09, 2019 11:14 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Neutron Test Sources Po210+Be or U238+Be?
Replies: 15
Views: 715

Re: Neutron Test Sources Po210+Be or U238+Be?

Adding to what RIchard said about alpha particles generated inside of rocks (or inside of, say, a chunk of Pu-238 oxide in a heat source for RTG). Alpha particle sources found in consumer products (e.g. Po in Staticmasters, and Am in smoke detectors) have the radioisotope in very thin films, sometim...
by Rich Feldman
Mon Jan 07, 2019 9:32 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Board Mounted LiI(Eu) scintillators - repost in neutron detection
Replies: 19
Views: 7116

Re: Board Mounted LiI(Eu) scintillators - repost in neutron detection

Yes, you need to provide the HV and resistor string. Pinout is given in Hamamatsu PMT datasheet, or you can trace pictures from earlier in this thread. Please let us know, yes or no, if you get a normal PMT signal from any of those units. With or without neutrons. I promise to complete that exercise...