Search found 56 matches

by Svilen
08 Jul 2018, 05:43
Forum: General discussion
Topic: My current setup
Replies: 7
Views: 2320

Re: My current setup

Hi Luuk, very kind from you, thank you! You have a private message with my address.
by Svilen
07 Jul 2018, 17:12
Forum: General discussion
Topic: My current setup
Replies: 7
Views: 2320

Re: My current setup

Thanks Steven. I want to check it's limits of detecting weak sources now..maybe something like trinitite or slightly contaminated soil. And something else - the top of the castle is like this because I wanted to complete it with a lighter higher stage (the lead roll I had was 200mm wide and the dete...
by Svilen
07 Jul 2018, 08:45
Forum: General discussion
Topic: My current setup
Replies: 7
Views: 2320

My current setup

Just to show you how my setup evolved in the last months and maybe you will have any comments/corrections/ideas to improve the performance? Driver: GS-1100A2 Detector: Thermo Scientific SPA-3 (2”x2” NaI(Tl) crystal) Sound card: Aureon XFire 8HD (192 KHz sampling) Shielding: 3mm copper + 25mm lead ht...
by Svilen
07 May 2018, 08:52
Forum: Detectors
Topic: Harshaw 8S8/2A-X
Replies: 18
Views: 8284

Re: Harshaw 8S8/2A-X

Hello Hendrik,
Your schematic is correct and I guess this is my picture you were looking for:

Image

Greetings,
by Svilen
16 Dec 2017, 07:33
Forum: Spectrum
Topic: CS-137 Spectrum, new shield
Replies: 24
Views: 7727

Re: CS-137 Spectrum, new shield

The potassium iodide I ordered arrived today and I think the mystery is more or less solved now. The strange peak was a compressed spectrum of K40 and lowering the HV with 100V put it in place. Now checking it with KI proved the theory I guess. There is still a lot to play with different hardware an...
by Svilen
15 Dec 2017, 20:01
Forum: Spectrum
Topic: CS-137 Spectrum, new shield
Replies: 24
Views: 7727

Re: CS-137 Spectrum, new shield

Yes, seems higher quality sound card is not always better for this. On my other laptop, which is of higher quality I don't get anything, maybe need more adjustment though. But maybe higher sampling rate can be achieved. I use now 48000, what is best?
by Svilen
15 Dec 2017, 11:17
Forum: Spectrum
Topic: CS-137 Spectrum, new shield
Replies: 24
Views: 7727

Re: CS-137 Spectrum, new shield

For good or bad I also do post from a place with organic matter :) Just hope this peak, that after the HV adjustment is now closer to 1400KeV, will fit the K40 energy after calibration and a check with KI.
by Svilen
15 Dec 2017, 09:56
Forum: Spectrum
Topic: CS-137 Spectrum, new shield
Replies: 24
Views: 7727

Re: CS-137 Spectrum, new shield

Yeah, the resolution is also a more realistic one of around 8%. I thought the lower voltage could extend PMT life and also wanted to go for it, but in 1100V it looked that I got more and stronger pulses so I used it. I definitely have to try a good external sound card also..maybe I'd get an used sou...
by Svilen
15 Dec 2017, 08:42
Forum: Spectrum
Topic: CS-137 Spectrum, new shield
Replies: 24
Views: 7727

Re: CS-137 Spectrum, new shield

Thanks for all the helpful comments! Seems it really is a compressed spectrum and this peak is from a higher energy. I lowered the HV today with 100V and run now the detector on 1KV insted of 1.1KV, which gave maybe more realistic results which you can see below. I don't know the optimal voltage for...
by Svilen
14 Dec 2017, 12:09
Forum: Spectrum
Topic: CS-137 Spectrum, new shield
Replies: 24
Views: 7727

Re: CS-137 Spectrum, new shield

Yes, maybe that's the next thing to try...just I don't have another detector at the moment. But it seems the shield is OK at least, do you agree?