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    I fully support this kind of content. It is as lobsteresque as it comes. I enjoyed the descriptions of the maths behind it all.

    I have some comments

    1. The description of the actual hardware is a bit buried, and should have been a bit more front and center. I’m still not sure what it is exactly, but it looks to be a geiger counter attached to an interrupt pin which is used to sample from a counter.
    2. Not clear if the banana has an actual role here, besides being a McGuffin, since the counter is likely mostly responding to the background radiation.
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      My experience with bananas and geiger counters is that the banana is the dominant source of radiation. Background radiation varies, so if you are in a radon filled basement or in the Chernobyl exclusion zone, your experience may be different.

      Also, a medium size white potato has twice the potassium of the average banana. So you would probably get more entropy with a potato. But, on the other hand, bananas are inherently more funny.

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        I dunno, potatoes are pretty funny too. I wonder if one could build one of these that uses the potato as a battery to power itself as well?

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            I think that Brainiac75 is using the wrong kind of Geiger counter. There are different kinds of Geiger counters, using different kinds of detectors. The low energy beta radiation emitted by a banana can’t penetrate most solid objects, so you need the right kind of detector to measure it. The Geiger counter in Brainiac75’s video appears to be the wrong kind. The right kind of Geiger counter typically has a cylindrical “wand”, connected to a box. The wand contains an “end window” type Geiger–Müller tube. The end window (at the tip of the wand) is made of mica, which the banana’s beta radiation can penetrate. The radiation can’t penetrate the sides of the tube.

            Reference: https://en.wikipedia.org/wiki/Geiger%E2%80%93M%C3%BCller_tube

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              Later on in the video he shows recordings from pure potassium.

              From https://www.epa.gov/radtown/natural-radioactivity-food

              Each banana can emit .01 millirem (0.1 microsieverts) of radiation. This is a very small amount of radiation. To put that in context, you would need to eat about 100 bananas to receive the same amount of radiation exposure as you get each day in United States from natural radiation in the environment.

              It does seem to be that the radiation from a single banana is pretty close to background levels.

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        @ozel pointed out to me that the banana has no effect on the sensor. They would get the same effect if they removed it.

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          I get it now. The given design uses an end-window type Geiger-Muller tube, and the window is not pointing at the banana. Probably it would work if a pancake tube was used instead.

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            Why does the banana have no effect? Banana + geiger counter video: https://www.youtube.com/watch?v=X_XVRA5nD6M

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            A home edition of HotBits? What a great idea!

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              I want to know who eats Bananas with Lemon and Sugar. That sounds strange to me.

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                When I saw the first image I jumped to the (wrong) conclusion that they’d take an image of the banana in its current state of decay, because (per banana) where the brown spots appear should be random. But maybe it is skewed towards certain spots, I have not studied banana browning in detail.

                Maybe time for another project.