During the Second World War Nazis established a uranium mine in Krkonoše mountains. Extracted ore was used in a research facility in Oranienburg. After the war, the mine was in polish borders, but Poland was then a puppy country of the USSR, so the ore was still extracted, but now was transported to the USSR. Later the mine was used in civil research.
My construction uses three GM tubes instead of one - that's why the amount of pulses per period of time is also three times bigger. Don't panic! :) In addition, even if radioactivity is a bit bigger that in (for example) my home in Wroclaw, it's still not hazardous for health.
As a reference, at home my Geiger Counter shows around 60 pulses per minute.
As you will see below results were bigger than those that I observe at home, is it due to the uranium ore that is near? Maybe, I'm not sure, I wasn't on any other mountains with my counter, so I can't verify it.
32F429IDISCOVERY board is used to count pulses and show results, it requires 5V power supply, the same as my Geiger Counter. Both were supplied from DC/DC converter (the cheapest I could buy), and 3xAA NiCd batteries. In total 250-300mA was drained from the batteries.
Final adjustments of the latest HW version - as usual, I made mistakes during the design of the PCB.
Geiger Counter in a package, ready to use outdoors. Note that both unisolated electrodes of the GM tubes are accessible. One has +400V, so it definitely isn't a good package for such device. Anyway, since I din't have time to make something better, since it will be used only one time and since it will be used only by me, I decided to make it this way.
Inside view. I was afraid that the PCB's will move inside and made shortcuts, so I've added paper balls to reduce the movements. The final version has even more of them.
Mountains "starts" - 0.5h from the bus station in Karpacz city. 77 pulses per minute.
Near the first mountain shelter that we encountered. 105 pulses per minute.
Hundreds of meters from peak of the Śnieżka mountain. 93 pulses per minute.
On the peak of the mountain. 91 pulses per minute.
On the pick of mountain, but just couple of hundreds later. Note those granite rocks. Granite is frequently a little more radioactive. 139 pulses per minute.
About 2km to the lakes, near the Śnieżka. 93 pulses per minute.
Hundreds of meters to the lakes. Note this fantastic cat. 107 pulses per minute.
That's all. I hope to present more results in future.