Gamma Spectrometry Forum

I have been working like crazy on an upgrade to Impulse, steep learning code, countless hours of coding 😵‍💫

The program was getting so large and complex that it became very difficult to work on, so today I finally had a working version and I decided to push it to Github.

I need a few of you guys to test it and report back to me if you find any bugs.

So what are the changes ?

In the new version you can publish your spectra for other Impulse users to see, and likewise you can see the spectra that others publish.

New Details Tab
This tab is for your personal details, but every field has a privacy option and can be turned on or off.
After you complete all fields you need to request an API key for secure uploads to the server.
Only one API key will be issued for the same email.
2D Histogram Tab
On the 2D histogram page there is a new button called "publish".
When you have proudly recorded a great spectrum, updated calibration and want to show the world, you simply click "publish", the spectrum along with your details will be visible to all other Impulse Users.
Changed your mind after uploading a spectrum, no worries, you have complete control and you can delete it from the "My Published Spectra" panel

Public Spectrum repository tab
This is where spectra will appear and there is a convenient search box that allows you to search for spectra by any recorded field.

Feedback appreciated 👍

Steven

Hi Guys,

I just pushed an updated version to Github.

Fixed calibration of thumbnail spectra, improved responsive design and updated the manual 👍

Does anyone want/need step by step instructions how to install and run Impulse?

Download Here: https://github.com/ssesselmann/impulse


Steven

I'm a newcomer to the idea of using a soundcard as a MCA. I understand it apparently works and is a popular thing. On my scope, I see the pulses coming out of my PMT return to the baseline after only a few microseconds, apart from the very largest ones which might extend to say 10 or 15 microseconds. This waveform does not seem necessarily a good match to an audio-input device with a 20 kHz audio bandwidth. I understand that even an arbitrarily short impulse applied to a low-pass filter does give you a signal with the decay rate of the filter's time constant, but that means there will be some dead time, or two closely adjacent pulses appear as one with larger amplitude, so the spectrum accuracy is affected.
Does this software work with 192 kHz soundcards? If I obtained a cheap 192kHz USB audio input device, would it likely even have more than 20 kHz analog input bandwidth, or is this sampling rate on audio devices just a marketing gimmick, and they assume no one will ever know or care what the true measurable bandwidth is?

EDIT: nevermind about the theory questions, having now got the package to run on my laptop, I see it offers up to 384 kHz sample rate, and reports an expected dead time. I'm still curious about what USB soundcards are likely to actually perform well (and especially if they are also inexpensive.)

jbeale,

Thanks for your questions. Sound card spectrometers perform much better than one would expect, pulses are passed through a filter and stretched to around 100 µs and the results are great, in fact there is no difference in resolution between a sound card and traditional high end spectrometers, the only disadvantage is the count rate. Whereas high end spectrometers like my GS-MAX range can count up to 200,000 cps, a sound card can only handle around 2000 cps., however most students and amateurs using a 2" or smaller scintillation detector, will never encounter much more than 2000 cps., and in the extreme case where the count rate is too high, you can just move a bit further from the source..

PS: Please respect the real name policy in our forum. You can add a signature section to your post with your Name, City and Institution (optional)

Steven

Hi Guys,

Good news if you are Mac user (apart from being a Mac user), the new Impulse version has been compiled for Mac 👍

Just download the Mac dmg file here. https://github.com/ssesselmann/impulse/releases and drop it in your applications folder

As is usually the case Windows compiler doesn't work..., but you can still run Impulse from the command line.

Steven