PART 2.
I got myself a transformer 10’’ Tablet/PC with Windows OS so the PDS software can run on it. I wanted something as portable as it could be in order to be able to record data and analyse them while in travel.
Just a few seconds and you can see your spectrum on the screen, both in Logarithmic and Linear view.
You can also see real time data from the detector (graph and reading).
- Real Time Graph-12.png (81.1 KiB) Viewed 11366 times
- Real Time Read -13.png (73.68 KiB) Viewed 11366 times
Here’s a better view of the spectrum in Lin and Log view. Calibration looks pretty good. You cannot subtract the background, so what you have is "background + sample".
- Radium_Clock_100819_1998secs_Lin-14.png (76.1 KiB) Viewed 11366 times
- Radium_Clock_100819_1998secs_Log-15.png (80.81 KiB) Viewed 11366 times
If you access the software as administrator (which you can do by logging in using username and password which are in the manual) you can recalibrate the detector if necessary. I had to do that as soon as I started to use it, about three weeks ago, because in the first spectrum I recorded calibration was off by 30% across the board. I only had to slightly adjust calibration once since then.
- Calibration.png (80.18 KiB) Viewed 11366 times
You can see the spectrum screen the average equivalent dose rate is showed.
Whatever the actual acquisition time was the software screen will never show an acquisition time longer than 999 seconds. So if you want to remember what the average CPS was you have to save the duration of the test separately (like for instance taking a photo of the detector display once the acquisition is over).
Here you can see the spectrum analysis of the test I did on the Radium Clock with my GS 2’’x2’’ NaI(Tl) last May (
viewtopic.php?f=5&t=512).
You can see in terms of exposure (and equivalent dose) the result of my calculation based on the spectrum and that from the PDS are in good agreement. It's worth mentioning that the background was not exactly the same, although difference is small, and that the distance between the sample and the crystal cannot be exactly the same for both measurements.
You can in theory also have isotope identification adding another software component.
The device is really amazing and I already have a list of places, both in Italy and abroad, where I want to take some measure with it.
But I also have some small “complaints”.
1 – the average equivalent dose on the detector display shows three decimals, but once you transfer the data to the software the third decimal place is lost. So 0.217 µSv/h becomes 0.21 µSv/h.
2 – The spectra can be saved in the computer or tablet memory, so they can be erased from the detector’s memory. Once in the computer files are surprisingly small, just a few Kbs. Nothing wrong with it, only problem is if you load the spectra from the computer instead from the detector the average equivalent dose rate isn’t there (there’s just a zero there), so this is another data you have to save separately, unless there’s another way I still didn’t find out about.
3 – The detector runs on two AA batteries, which can be alkaline or rechargeable (the charger is included). Every time you turn on the device it will ask you to set the kind of batteries currently on use. That’s perfectly ok, but the charge level indicator at times seems to go up and down a bit erratically. As soon as you exit the Bluetooth mode it looks pretty down, then it goes up again, so it’s not easy to exactly know how much battery is left.
When the battery is really down the detector will automatically exit the Bluetooth mode after just a few seconds. so that’s the best indication you have.
A part from these few things, that’s one of the best “toys” I have ever had.
[broken link removed - Steven]
