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by SiempreViernes 2176 days ago
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 : /
2 comments

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, though.

Yeah, I feel like listing out the "raspberry pi, brass and wood" created the expectation that those were the crucial elements. Really the crucial element is a pre-made geiger counter and what they built is a beautiful enclosure and display. It's a cool project and they didn't lie, but it was misleading, and it seems it was the author of the piece who posted it so the confusion is reasonable to call out.
I thought it would be a gold leaf electroscope

https://en.wikipedia.org/wiki/Electroscope#Gold-leaf_electro...

>By 1880, Langley's bolometer was refined enough to detect thermal radiation from a cow a quarter of a mile away.

Sidenote: that sounds like even F-22/35 should be visible half a globe away in IR

Be careful of that inverse square law—it's a doozy!
OP links to their repo which has full instructions on how to integrate a geiger counter board with the RPi: https://github.com/balenalabs-incubator/background-radiation...

Even has some links to the model(s) used.

I hope you see the difference between building a Geiger tube and buying one.
Building a Geiger tube is probably beyond the reach of most people. That’s a precision piece of equipment.
I'd argue that it is beyond the perceived reach of many people, but it is not beyond the actual reach of many people.

The key ingredients are aspiration and time.

This got me thinking: how far down the current human tech tree could a single person get on their own? It took thousands of years for humans to go from fire to the steam locomotive; could someone do it in a lifetime?

Obviously the ability to skip by basic research and dead ends would cut this down by a ton, but ultimately a lot of the things we’ve created in the past century requires a huge amount of complicated machinery to make, which requires more machines and more labor. Could a person reasonably start from scratch (let’s say skip the mining and just give them coal & metal ores) and make a Geiger tube? Or would it be too difficult?