But its closest equivalent is  sold at much more.  Wish us best at the Ken Spencer competition. In the meantime, the CAD, C-code, assembly code, and a few more DIY instructions should go up soon.  Hopefully such a simple device goes far. On the plus side, this implementation also includes a playback feature, so that the most recent ‘x’ seconds of audio are always recorded, and are always available for playback. Very useful when a hearing condition interferes with listening to the radio, TV, a conference, or more.