Our countdown to Wuthering Bytes 2016 and the Open Source Hardware User Group's OSHCamp has thus far concentrated on the talks to which attendees will be treated this weekend. While a great reason to attend, there's something extra to tempt people along: as always, OSHCamp guests will be given a special electronics kit to take home and build - or assemble during the traditional soldering workshop on the Sunday - with this year's swag-bag containing the Denkimono Noise Generator Kit.
The 'noise' that the kit creates doesn't refer to sound, although thanks to an on-board piezoelectric buzzer it can indeed do that; rather, the Noise Generator is designed to create high-quality entropy to produce a stream of random numbers between 0 and 99. While primarily designed as an interesting pocket toy, the technology within Denkimono's board matches that used by many hardware random number generators (HRNGs) - used in high-security applications where the pseudorandom number generation (PRNG) of traditional computer hardware just doesn't cut the mustard.
Building the OSHCamp kits is always a great reminder of the weekend, and we've been lucky enough to get our hands on one of the kits ahead of time. The below video shows the build process from start to finish; if you want to go into it fresh and with no foreknowledge then we'd recommend not hitting the 'play' button!
The way the device operates is clever indeed: using a high voltage the board induces an avalanche breakdown in a transistor's base-emitter (P-N) junction, causing it to conduct when it would normally resist conduction. This, naturally, causes interesting things to happen to the circuit in the form of unexpected voltage fluctuations; an on-board microcontroller measures these unpredictable fluctuations and generates a stream of numbers using the least significant bit (LSB) of each reading. These numbers can be turned into random 'white noise' through the speaker, displayed in the form of integers in the range 0-99 on the double-digit LED display, or even streamed to a computer system via a serial connection - the latter allowing for using the tool as a means of feeding quality true random numbers into a computer's entropy pool.
Full details of the kit are available on the project's GitHub repository, and if you want to get your hands on a ready-to-build kit version you'll be wanting to attend OSHCamp 2016 on Saturday for the talks, Sunday for the workshops, or both to get the full experience!