[liberationtech] Efficient digital one-way communication

[Jens Christian Hillerup]

On Sun, Mar 3, 2013 at 3:25 PM, Jens Christian Hillerup
<jens at hillerup.net> wrote:
> I did a quick hack back in September, called modulera [1]. The idea is
> to exploit how pentatonic polyphony always sounds good, regardless of
> the notes picked (as long as they're within the scale). The way it
> works is that it takes three octaves of some pentatonic scale (in this
> case F# major), and silence. This gives 16 different notes. Split up a
> byte into two nibbles and you get your two tones.

Oh, and before anyone notices, there is currently no way of telling
the ordering the nibbles at demodulation time. Also 0xAA = 0xA0 =
0x0A. As I said, this is (for now) just a toy; there are certainly
things that need to be addressed.

JC