Search found 323 matches

by Rex Allers
Tue May 19, 2020 2:55 pm
Forum: Announcements and Site Administration Topics
Topic: Edit posts
Replies: 16
Views: 830

Re: Edit posts

Frank, I just found one of my old posts that has the inline attachment issue. Filename is there and opens the image if clicked on but the thumbnail doesn't show in the message. This one: Re: MKS 901p by Rex Allers » Fri Jun 08, 2018 9:06 pm https://fusor.net/board/viewtopic.php?f=10&t=11533&p=80133#...
by Rex Allers
Tue May 19, 2020 2:10 pm
Forum: Announcements and Site Administration Topics
Topic: Edit posts
Replies: 16
Views: 830

Re: Edit posts

Frank said, "The photos of those with the ID numbers starting with a 4 are gone according to Rex." Not quite right, I wish it was just 4. It is 4 or greater. From what I see in posts, the users who lost all their uploaded files in the move are users who's ID number begins with the number 4 or more (...
by Rex Allers
Sat May 16, 2020 12:50 am
Forum: Announcements and Site Administration Topics
Topic: Edit posts
Replies: 16
Views: 830

Re: Edit posts

Tyler, Good work. Thanks. Frank, Re: "Let see the others in the thread can do theirs too. Rex, Rich and Rich?" I assume by that you mean me, Rich Feldman, and Rich Normand. None of us three are suffering from the post-move global attachment loss syndrome. But there's another weird glitch that happen...
by Rex Allers
Sat May 09, 2020 3:36 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Ludlum model 3 issues
Replies: 12
Views: 627

Re: Ludlum model 3 issues

Sarmad, None of that explanation makes any sense to me. There's no 64W pot in a Ludlum 3. The batteries probably couldn't supply 64W if they were shorted. The little pot for HV adjust setting is probably 100K ohm. In the circuit it should draw microamps and micro watts. Not sure how you were measuri...
by Rex Allers
Fri May 08, 2020 12:05 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Ludlum model 3 issues
Replies: 12
Views: 627

Re: Ludlum model 3 issues

Did you find something that made it start working? Does it go beyond 750 V?
by Rex Allers
Thu May 07, 2020 2:10 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Ludlum model 3 issues
Replies: 12
Views: 627

Re: Ludlum model 3 issues

Sarmad, I spent a bit of time today trying to understand the Model 3 circuits. It seems that the Mod 3 manual on the Ludlum page I linked earlier has schematics and board layouts that don't match yours. I assume the doc is for a newer version. One significant difference is the shape of the board tha...
by Rex Allers
Tue May 05, 2020 8:19 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Help with HV adjustable power supplies for radiation detectors.
Replies: 22
Views: 1865

Re: Help with HV adjustable power supplies for radiation detectors.

John,

Any chance you could find and share a link (Mouser or etc.) to the kind of supply you are talking about?

Or details of the manufacturer/model.
by Rex Allers
Tue May 05, 2020 7:53 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Ludlum model 3 issues
Replies: 12
Views: 627

Re: Ludlum model 3 issues

Richard, not sure your easy answer is correct. I've never had a Ludlum Model 3 so have zero direct knowledge but here's a version of that pic that I modified. Lud3 pic.jpg So I added two outlines of possible connections on the board, one is orange, one is green. You propose an inline set of connecti...
by Rex Allers
Thu Apr 23, 2020 7:59 am
Forum: Items wanted
Topic: Edwards TAG controller
Replies: 6
Views: 629

Re: Edwards TAG controller

I'm not an expert but I did a little looking at documents and your original post doesn't make sense to me. The EXDC doesn't seem to be a turbo pump but rather a control module that attaches directly to one of several ETX... turbo pumps. If you have an EXDC mounted on the side of an ETX turbo, it loo...
by Rex Allers
Sun Apr 19, 2020 7:41 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Solderless Grid Design with Shaft Coupler
Replies: 8
Views: 898

Re: Solderless Grid Design with Shaft Coupler

Your work on this grid is really good, I congratulate you. I'm thinking, though, that you seem to have a small cylindrical chamber. Maybe a cylindrical grid like one of Doug Coulter's designs might be appropriate to also try. Here's one I made. grid example.jpg Needs a lathe to make, though. End pie...