Does anyone have a link to any article about their previous white space radio effort? I'm interested in learning more about their failure in that field and what

Does anyone have a link to any article about their previous white space radio effort? I'm interested in learning more about their failure in that field and what were the hurdles he is referring to. I can't seem to find them on the YC summer 2012 list and their new nutrition thing is all that comes up in my web searches.