December 15, 2015 at 07:25One GMS is good, and two is better
In my previous article about weak household radiation, I used a SOEKS Defender dosimeter equipped with an SBM-20-1 counter . As many commentators noted, its accuracy is not enough to reliably measure a weak background, and I had to go to some tricks to detect potassium-40 radiation in bananas. Now, the more advanced SOEKS Quantum has come to my test . Thanks to the use of two Geiger counters at onceSMB-20-1, measurements are made faster and more accurately. The results are stored in the non-volatile memory of the device and can be downloaded to a PC or Mac for further analysis. Quantum is that rare case when a domestic gadget does not have a twin brother with a different label on Ali, and is also known abroad .
Anboxing
The dosimeter arrived in such an elegant box:
Inside - the device itself, the charger, USB-A / mini-USB cable:
AAA batteries should be in the empty cell in the lower right. It turned out that someone had already put them in their place (I remind you that at the time of writing the review of this dosimeter was not in the Dadget range, I received a test copy). Two 1000mAh Ni-MH batteries under the SOEKS brand. The manufacturer promises a continuous time of at least 700 hours.
Power supply for 5V 1A. C back side - USB port, so that in addition to the dosimeter itself, you can charge the phone.
USB-A / mini-USB cable for charging and connecting to a computer.
The mini-USB port on the dosimeter is closed with a rubber plug.
Comparison of the dimensions of SOEKS Defender (left) and SOEKS Quantum:
I hid the animation with the 3D model under the spoiler ...
Insides
The dosimeter case is quite simply opened. Under the small white inserts are hidden two screws fastening the halves of the body. In addition, the large side inserts further hold the halves together.
On the reverse side of the board, there are really two SBM-20-1 sensors:
Front side. Color TFT display 128x160.
The device operates on the STM32F103C8T6 microcontroller (which xedas recently wrote about ):
Interface
The main mode of operation in the photo below is background measurement. The level of radioactivity is displayed in large
numbers in the center of the screen. The unit of measurement can be selected in the settings ( sievert , x-rays or the number of counts per minute). Below, last-minute background diagrams are displayed for the left and right sensors,
respectively. The diagrams continuously move towards the
center, the height of the column displays the background radiation level. If the threshold specified in the settings is exceeded, an audible signal sounds.
In the "History" mode, a scrolling diagram of the history of changes for the entire time from the moment the device is first turned on (or from the last discharge of the accumulated dose) is displayed. A small “plateau” in the left quarter of the diagram corresponds to the time spent inside the crystal beer mug from the article about Defender .
Indication of the accumulated dose of radiation. If necessary, the dose can be reset to zero, or set to some other value (for example, if you have previously used another device and want to continue collecting statistics).
This photo was taken 12 hours after the previous one, 1.3 μSv (or 13 bananas ) came running .
The accumulated dose is not reset even if the batteries are completely discharged (or even removed). But keep in mind that the date and time settings will be lost at the same time, which can cause confusion if you need detailed statistics of measurements with reference to time (more on this later).
You can watch the rest of the user interface screens yourself - the manufacturer was not too lazy to make the SOEKS Quantum emulator , which works in a browser and fairly reliably simulates the operation of a real dosimeter. Three clickable device control buttons are located below the screen. Detailed instructions are also available . This interface caused a burning nostalgia for the first mobile phones with color displays 12 years ago.
Computer connection
There is no traditional disk with software in the box, download the SOEKS Device Manager independently:
Windows: soeksdevm-setup-2.0.2.3.exe
MacOS: soeksdevicemanager.dmg
Through the application, you can update the dosimeter firmware, calibrate the readings:
You can monitor the readings in real time, both for the average value and for the readings of the left and right sensors separately:
You can also download from the non-volatile memory of the device the history of measurements taken away from the computer. The recession in the following graph shows how the background in the bathroom changes as a result of intensive ventilation. Previously, I turned off the hood for 10 minutes and started up hot water. Apparently a little radon is dissolved in tap water. The units are μSv / h, there is no danger.
Data for a desired period of time can be exported to CSV for further analysis:
By the way, the measurement history is automatically saved in the home directory in the SOEKS Device Manager folder and remains available for viewing when the dosimeter is turned off.
Details about working with the program - in the user manual .
Comparison with Soeks Defender
Now it's time to figure out why two sensors are better than one. You have already noticed on the chart how much the readings of the sensors dance. Averaging the readings from two sensors makes it possible to smooth out these fluctuations and quickly obtain a reliable value of the background level. The video shows how long the value of the background floats after turning on Defender, while Quantum starts to give stable readings much faster. I accelerated the second half of the video six times so that you would not get bored when watching.
Video reviews from other authors
SOEKS Quantum Geiger Counter Demo
Dosimeter "Quantum" - measurement of radiation background during a campaign and expeditions
Dosimeters and indicators of radioactivity SOEKS
conclusions
| pros | Minuses |
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You can buy SOEKS Quantum in the Dadget store .
