Well, last week has shown the total lack of any radiation around my home. I have got pretty stable reading for a few days, which moved a little bit higher and lower, but mostly consisted of random background-level noise. The noise (~0.2 clicks per second), which should be expected from this kind of geiger tube at their respective age.
While this kind of picture looks quite dull and boring, I’m kind of cowardly reluctant of ordering any kind of radioactive materials to my home, so I’ve decided to take another approach. I’ve heard the granite stones are supposed to have 0.3-0.5uSv/hour levels, so probably tomorrow would be a good time to visit a stone sculpture factory nearby.
And for that purpose, here comes another board, this time without any USB connection, but equipped with a small LCD screen, so I can attach a pair of batteries and use it to see the results while away from home. Also I’ve got a cheap (relatively) Chinese dosimeter, so there’s a hope I can calibrate the output of my boards and don’t rely anymore on thumb-sucking approach when calculating CPM-to-uSv/h conversion rates.