IMPULSE by Gammaspectacular    (Only software compatible with Mac & Windows)

Impulse is a free open source gamma spectrometry program developed by Steven Sesselmann for the Gammaspectacular sound card spectrometer, but will also work with other sound card based devices. 

Unlike  most free applications for gamma spectrometry, Impulse is open source and can be modified by you to suit your own application. Impulse has the essential pulse capture and filtering functions that make sound card spectrometry possible, while still allowing the user to code their own output.

Impulse runs on Python

Python is a popular scripting language in the world of science, but for those of you who are no familiar with python, think of it like Excel, it is a program for opening a spreadsheet, or in our case a program for running our script. 

Unlike Excel, Python can be downloaded for free from the official web site here : www.python.org

Python is  available for Mac, Windows and Linux

Impulse opens up in your default browser

Unlike traditional apps which have their own GUI interface, Impulse opens up in your browser, it has a tabbed view and currently displays 4 tabs. 

Tab-1 Setup Options

As soon as you launch Impulse, your browser will open up on tab 1 where you can get a list of USB input devices and select your spectrometer.

Once you have selected your device, you have the option to select sample rate and sample size, before running the pulse shape capture function. 

Pulse shape capture typically takes a few seconds to run which is confirmed by the appearance of the visual pulse on a graph. 

At this stage it is also a good idea to run a distortion curve, this gives you a visual representation of the mean distortion, i.e. how much the unfiltered pulses differs from the mean pulse shape.

On the top right hand side you will receive live updates whenever a new version is available and occasionally a brief note about the update.

PS: All settings save automatically and will be remembered next time you run the program.

Tab-2 Pulse Height Histogram

Tab 2 displays the pulse height histogram plus a number of additional settings relevant to this page. 

Most of the buttons and fields are self explanatory, but for a more detailed explanation you may click on tab-4 where you find the full manual. 

Summarising the main functions on tab-2.

• Pulse height histogram
• Start/Stop function
• Total counts and cps
• File name input (saves to NPESv1.0 format)
• Number of bins (width of spectrum) 
• Size per bin
• Stop condition
• Lower Limit Discriminator LLD
• Shape tolerance (from tab-1)
• Comparison spectrum (select any previously recorded spectrum as comparison)
• Isotope library - Show peaks from any one of 480 isotopes
• Comparison spectrum overlay
• Subtract comparison spectrum
• Rescale y axis as , log or energy per bin
• Play a 3 second audio of selected spectrum
• Three point calibration with second order polynomial fit
• Peak finder 
• Gaussian correlation

Tab-3 Count rate histogram

The third tab contains the count rate histogram with 10 second moving average. 

Users can switch between tab-2 and tab-3 without upsetting the recording. 

Tab-4 Exit, Export and Manual

The main function of the last tab is to contain the manual, but you will also find a few additional functions. 

Select Theme

There are a selection of different background styles to choose from, these will do nothing to improve your spectra, but may brighten up your day.

Export data to CSV

Here you will also find a function where your recorded spectrum can be exported to your downloads folder as a CSV file.

EXIT

Last but not least, it is recommended that the exit button be used to close the program, rather than just closing the browser. the exit button terminates the process running on your server. 

Mac users please use this one