Search found 64 matches

by Mike S
12 Oct 2020, 10:33
Forum: Physics, electronics and beyond
Topic: Any Stereo Microscope Users?
Replies: 3
Views: 2129

Re: Any Stereo Microscope Users?

[This post was mistakenly edited and most of the content was removed. I'm summarizing what I had before so the thread maintains continuity.] In the post that went missing, I thanked Svilen for the information and said that I subsequently tried his suggestion and several different solutions using a D...
by Mike S
21 Sep 2020, 03:18
Forum: Physics, electronics and beyond
Topic: Any Stereo Microscope Users?
Replies: 3
Views: 2129

Any Stereo Microscope Users?

After being fascinated by the view of my trinitite samples using what is essentially a high-end kid's microscope, I decided to get a (relatively) inexpensive stereo microscope (trinocular Swift S7 zoom). I'm really enjoying the microscope, but I'm finding it hard to get information on accessories. C...
by Mike S
06 Sep 2020, 09:02
Forum: Spectrum
Topic: Uranophane from the Black Forest (Germany)
Replies: 4
Views: 2255

Re: Uranophane from the Black Forest (Germany)

As always, very nice, and very informative.

Thanks for sharing!

--Mike S.
by Mike S
31 Aug 2020, 09:22
Forum: Detectors
Topic: Bad 3x3? or is it just me?
Replies: 16
Views: 5864

Re: Bad 3x3? or is it just me?

I think I'm ready to say the detector is bad. After taking a break from this, I'm trying to wrap-up and document the detector issue. I'll share what I think I know, and I'd appreciate any feedback or ideas. The next step will be asking the seller for a refund and see how that goes. What I've done: -...
by Mike S
20 Jul 2020, 14:29
Forum: Detectors
Topic: Pulse height shift with pulse rate?
Replies: 9
Views: 3216

Re: Pulse height shift with pulse rate?

Mike et.al., I just did a quick test with the GS-USB-PRO and one of my standards GS-1515 NAI detectors using a Cs137 source placed at 15, 10, 5, and 1 cm. with count rates varying from 221 cps, to 1710 cps. and see no significant drift. The slight drift we see is more likely due to temperature chan...
by Mike S
19 Jul 2020, 05:53
Forum: Detectors
Topic: Pulse height shift with pulse rate?
Replies: 9
Views: 3216

Re: Pulse height shift with pulse rate?

I can also make a contribution to this topic. I also recorded different pulse frequencies for my system. But I also have to say that my high voltage is very stable and the resistances between the dynodes of the PMT are very low. So the lines do not change, but the intensity is influenced. It is lik...
by Mike S
15 Jul 2020, 02:01
Forum: Spectrum
Topic: Gummite, Uranium Ore from Australia
Replies: 5
Views: 3042

Re: Gummite, Uranium Ore from Australia

Excellent work as usual Massimo! I learn a lot from the spectra you share along with your process and equipment details. Please keep sharing. According to the seller this sample was hot enough to give a dose rate at contact of 5 μSv/h, but that was actually an overestimation, we are more in the regi...
by Mike S
14 Jul 2020, 17:54
Forum: Detectors
Topic: Bad 3x3? or is it just me?
Replies: 16
Views: 5864

Re: Bad 3x3? or is it just me?

To start to isolate and understand the factors that contributed to the improvements, I did a comparison run with and without the ground strap to the detector case. The difference is clear to see. Note the big peak about 8 keV is just noise, but I think it helps illustrate the point. The red trace is...
by Mike S
14 Jul 2020, 13:38
Forum: Detectors
Topic: Bad 3x3? or is it just me?
Replies: 16
Views: 5864

Re: Bad 3x3? or is it just me?

Thanks Everyone! We're getting somewhere now. Here's what's been done, and the much improved spectrum is attached: 1. Added grounding strap so detector case is connected to signal/HV ground. 2. After changing the Grid connection on my voltage divider and getting slightly different, but still weird r...
by Mike S
14 Jul 2020, 06:30
Forum: Detectors
Topic: Bad 3x3? or is it just me?
Replies: 16
Views: 5864

Re: Bad 3x3? or is it just me?

Thanks Tom! That's a great way to do the grounding, I'll implement something like that if I go with a more permanent solution. I did two short comparison runs with and without a ground strap (For testing, a 1/4" braid from BNC connector body to detector body held in contact with rubber bands). There...