“As previously reported, I’m on a slow track research project into randomness. Having explored the concept of random bits and built some experimental random electronics, I’m still progressing in my question to understand how randomness can be exploited both for understanding the fundamental process of creation and creativity as well as randomness as a shortcut for complex or even intractable algorithms.
I’ve learned a trick over the years: if you don’t understand what you’re doing, keep doing it. On that dirk-gently-esque premise I’ve designed and built a 4-bit analog random number generator. Below is the circuit diagram for one bit; it’s essentially the one as I used in my tests before. I have replaced the schmitt inverter by a transistor with a pull-up resistor.
Since I wanted a ‘few’ random bits, I designed a PCB that I got manufactured in China at JLCPCB. There service is excellent and the PCB quality just as good. Cheap too: 5 boards cost me 2 dollars (!) plus 16 USD shipping. It took a week from order to reception which is pretty good given that borders have been disrupted due to COVID19.
I haven’t designed circuit boards for a while and I was pleased to note that my track-laying skills are old school. I used to make complex boards with black tape rather than CAD software and autorouters were only someones dream at that time.
My soldering skills need adjusting though. In a time of SMD circuit boards, neither my eyes nor my solder iron tip are up to scratch. Still, I put it all together and after removing some solder shorts, got the circuits to work as per spec.”