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Arduino True Random Number Generator

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Step 5: Detect Radiation

Once the arduino has been programmed, you can run the processing sketch. The geiger counter should detect about 20 counts of radiation a minute, as natural background radiation. This equates to about 5 bits a minute, which is pretty slow. To increase the number of counts per minute, I bought salt substitute, which contains potassium chloride. A small percentage of potassium atoms are naturally radioactive (its still perfectly safe) , and we can actually measure the increased radioactivity with the geiger counter. I was able to get up to 60 counts per minute, or a bit over twice background radiation (again perfectly safe). The increase in radioactivity allows the counter to produce bits at a faster rate.
 
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kelseymh2 years ago
This is an awesomely cool project :-) I especially like your use of NoSalt as a 40K gamma source. You could also use bananas if you're so inclined ;-)
I think for the purposes of encryption and the building of an encryption key, I'd definitely use bananas. that way I could tell people that my data is "banana encrypted."

either that or say it's guarded with bananas. or something else ridiculous.
If you use it to encrypt your digital voice communications, then you can talk to people on your bananaphone!
ring ring ring ring ring ring ring ring bananacryption!