Show HN: I built a desktop radiation monitor with Raspberry Pi, brass and wood

Post by overfl0w » Tue, Jul 07, 2020, 4:43 PM UTC

matthewmcg wrote: post #39

overfl0w wrote: post #35

Great work! I liked how well the vintage look and the modern core fit. I'm not sure where I read it but it was stated that the Geiger counters which are manufactured after the Chernobyl (?) incident were not as accurate as those manufactured before it. The reason is that all the metal after the incident and the radiation experiments performed afterwards is contaminated with radiation particles which alter the radiati…

I don’t know about Chernobyl specifically, but so-called low background steel from before 1945 is harvested specifically for use in radiation sensing applications. See https://en.wikipedia.org/wiki/Low-background_steel I think most of the radionuclide contamination comes from Cold War atmospheric nuclear testing. Some low background steel is recovered from sunken battleships!

Post by mywittyname » Tue, Jul 07, 2020, 5:31 PM UTC

overfl0w wrote: post #35

Great work! I liked how well the vintage look and the modern core fit. I'm not sure where I read it but it was stated that the Geiger counters which are manufactured after the Chernobyl (?) incident were not as accurate as those manufactured before it. The reason is that all the metal after the incident and the radiation experiments performed afterwards is contaminated with radiation particles which alter the radiati…

Post by basementcat » Tue, Jul 07, 2020, 7:43 PM UTC

acidburnNSA wrote: post #41

dandigangi wrote: post #38

3.6 roentgen. Not great. Not terrible. Very cool project. Always impressed the level craftsmanship some people have.

If anyone wants some context about radiation dose units across various orders of magnitude, I recommend the charts in this DOE chart (see page 6) [1] [1] https://www.energy.gov/sites/prod/files/2018/01/f46/doe-ioni...

Post by acidburnNSA » Tue, Jul 07, 2020, 7:55 PM UTC

ISL wrote: post #34

SiempreViernes wrote: post #27

I was wondering how you would detect radiation with brass and wood, but it turns out this was actually talking about how to build a snazzy enclosure and not at all about how to detect radiation : /

I assumed that someone had made a sensitive bolometer. https://en.wikipedia.org/wiki/Bolometer Wood is a thermal insulator, so with care, one might be able to build a thermistor bridge capable of detecting the differential temperature rise between pieces of brass when a source was placed near one brass-piece. I, too, found that the expectations framed by the title were not met by the article. It's a pretty box, thoug…

Post by chrisys » Tue, Jul 07, 2020, 8:51 PM UTC

jacquesm wrote: post #56

chrisys wrote: post #47

Earlier quoted context omitted.

Thanks for the compliments, and I appreciate your eye for detail and nitpicking :) I don't even wanna think about how many hours I put into this thing. It was one of those projects when you've got some free time you just keep working on it, then eventually, one day, it turns out there's nothing else to do. For the Dekatrons, it was simply a case of I had 50mm stainless steel bar already in the shop, but the biggest b…

Super job. More nitpicking: the real fanatics line up the screw heads to the geometry of the piece. For instance the Dekatrons would look nicer if the screwhead slots would form a circle too.