This is a prototype of a simple battery-powered radiation detector built around Basic Nano MCU. Most of the circuitry is built on a perfboard, so there is no PCB included into this project.

It includes USB battery charging circuit and can use USB virtual serial port to send data (number of  radiation events per minute) to the host PC for display and analysis.

The most recent firmware source code can be found at GIthub: https://github.com/rita-gwen/GeigerCounter.

PCB design and the most recent schematic of the power management circuit can be found in this project: https://circuitmaker.com/Projects/Details/Rita-Chupalov/GeigerPower

Since CircuitMaker does not have a convenient solution for multiple PCBs in a project I had to move it out.

Next step will be to build a more professional intrument around one of Cortex-M0 MCUs.

A useful link on Geiger counters: https://www.electroschematics.com/12225/diy-geiger-counter/