The century-old tried and tested gas-discharge SBM20-1 Geiger-Müller counter remains the standard sensitive element in most household and professional dosimeters. The RadSens module serves as a radiometer and dosimeter, supporting measurement and calculation of radiation intensity via two algorithms.
The RadSens can function as a standalone device or as part of an external Arduino, STM, or Raspberry Pi system. In standalone mode, the module acts as a simple indicator, where the flashing of an LED signifies radiation level, speeding up as the level increases. Schematics are available on GitHub.
The dosimeter runs on logic based on an STM32 microcontroller Data received from the Geiger counter is transmitted via I2C interface, generating three values: radiation intensity calculated with an averaging algorithm for accurate measurement over a long time period, radiation intensity calculated with an algorithm for registering local sources of pollution with a dynamic range of calculation time, and the number of impulses registered since the last request to the I2C. Impulse registration, calculation algorithms, and data transmissions with a frequency of up to 400 kHz are all implemented on the MCU installed on the board. A register map and description of registers are also available on the GitHub page.
Other key features include software-level support of change in I2C address, a maximum current consumption at high radiation of no more than 50 mA, compact dimensions of just 89x21x13.5mm, and the ability to turn off the high voltage generator to reduce power consumption and fine-tune the counter sensitivity. The RadSens is a flexible, inexpensive way to gauge radiation and include that as a sensor in another project.