What's out there on the market now and how is what you're offering any better/cheaper/different/smaller?
RNG's today operate on thermal fluctuations and alternatively current "shot noise." These methods are in principle sources of quantum entropy. However, they work on integrated circuits so nobody knows whats really going on inside of it. One can perhaps test the legitimacy of the outputs, but I do not like the idea of ICs used in open source technology since they can always be backdoored - one must trust the IC manufacturer to use the IC.
This is different in that anyone with an electronics hobby can scrutinize it; these electronics presented are completely analog. One can also feel free to exchange the (sodium chlorate?) sample with their own if they believe I have doctored mine. It's simple physics, rather than black-box electronics.
Who is your target audience for this product?
Anyone who is worried about keys generated by deterministic algorithms. They are not guaranteed to be random, and if an attack is found, the bitcoins are gone (
https://www.google.com/search?q=android+vulnerability+stolen+bitcoins&rlz=1C1CHFX_enUS565US565&oq=android+vulnerability+stolen+bitcoins&aqs=chrome..69i57j0l5.5858j0j7&sourceid=chrome&espv=210&es_sm=93&ie=UTF-8). Perhaps it would be intended for large holders of coins or by servers who tend to generate a lot of keys...or advanced users.
Or even hardware developers who want to offer a bitcoin product, but are afraid they will create something that doesn't offer enough entropy, making their customers lose all their bitcoins, and bringing a lot of heat upon themselves.
I would make my design open source so they can modify it as they please, asking only that their version's build characteristics can also be documented properly.
How much would it cost to build the first one...
I have done much of the research already. The exact details like this would come after I have community input on what features are actually desired. How small do I need to make it to be desirable? How do you guys think it should output the random bits? Desired speeds?
Once I have answers to these questions, I can make concrete statements about dev cost and a timeline.
In short, I can make this work on my lab equipment already. That isn't satisfactory of course; I'm using a $100,000 signal generator, and a few $30,000 oscilloscopes.
But if I specialize the device to work for only a certain chemical, and function only in such a way as to be used in conjunction with bitcoin...it doesn't need to be made from expensive lab equipment. So once we decide the properties, I can choose an operating frequency, and really make a nice parts list.
For a rough estimate, for the type of device I have in mind...to buy the raw electronics for a one-time build...the parts would cost under $20. In the course of devlopment one should expect many failed attempts so the dev cost is much higher than the unit cost.
I already have most of the test equipment I would like or need to finish the job.