*update December 2025: I'm visualizing the data at https://storage.services.kibotu.net/geiger now.

After watching HBO's Chernobyl Series and stumbling upon this awesome article about someone building a steampunk desktop background radiation monitor I was inspired to build a radiation monitor myself. I'm aleady being using a Raspberry PI with pi-hole so I only needed to buy a a radiation detector from Amazon UK.
61Slv1uad0L-AC-SL1000.jpg

The following image shows to connect the pi with the Geiger-Counter-RadiationD-v1.1-CAJOE board.
pi-geiger-simple.png
How it works can be read here. Essentially there is a J305 pulse halogen tube connected to an Arduino board that will measure gamma rays from 20mR/h to 120mR/h and beta rays from 100~1800.

We can access the raspberry pi pins with the GPIO API. If we run pinout we see the following pin configurations.
pinout.png
The red cable goes on pin 2 and the black cable goes to pin number 6. Finally the green cable goes to pin number 7 which we use in our python script to count and measure pulse events which can we can then multiply with the J305 tube usvh ratio constant. Et voilà my living room has a background radiation between 0.13 and 0.35 µSv per hour.
Screenshot-2021-03-28-at-154935.png

Is that a lot? Not really. 0.1 μSv is also known as BED (Banana Equivalent Dose)

Here is a great video to get radiation into perspective:

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DIY Geiger Counter

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