I modified this open source hardware project because I wanted to make it available to more people for experimenting. With that being said, I didn't go the supper small SMD aproach like the original authors. I wanted the components to be easily soldered manually for everyone with only basic soldering knowledge. If you need PCB's let me know ;)
Arduino based TRNG results:
Software used: http://www.fourmilab.ch/random/
Command: ent.exe chaosKey_entropy.txt
Entropy = 7.999638 bits per byte.
Optimum compression would reduce the size
of this 500000 byte file by 0 percent.
Chi square distribution for 500000 samples is 250.83, and randomly
would exceed this value 56.20 percent of the times.
Arithmetic mean value of data bytes is 127.4989 (127.5 = random).
Monte Carlo value for Pi is 3.141996568 (error 0.01 percent).
Serial correlation coefficient is -0.001135 (totally uncorrelated = 0.0).
Resuts are not bad for arduino based TRNG, considering it only has 10bit ADC and we take lower 8 as our source of randomnes :)