Did he actually say how the data is gathered? It hinted at potassium decay but if he went into more detail, I missed it. And every experiment needs a control - does the banana add anything?
Author here. There is a part 2 that explains the generation in detail, you find it linked below the part 1, or at the link [0].
The banana does not make a significant difference (the generator can operate without it), however the potassium in general can definitely be detected. I've made some test with KCl and the increase in counts is huge. In the end this is not very important for the purpose of the project: i just wanted to tell a story involving true random number generation from radioactivity, and the radioactive banana is very functional for this purpose.
The detector is a Geiger tube. There are more details on the GitHub page [0], including this note:
> Disclaimer: the radioactivity from the bananas doesn't quite make the difference, the background radiation is more than enough to make the generator work and afaik the banana's is not even detectable.
Potassium Chloride is sold as a sodium-free table salt substitute and will give you far more decay events per second than a banana. I'd have to double check the decay rate in a kilo of KCl vs background radiation, but even if the decay rate is too low for random number generation you can still use it to salt your hashes[0].
