How to Hack Radio Frequencies: Building a Radio Listening Station to Decode Digital Audio & Police Dispatches

On April 7, 2017, residents in Dallas, Texas, woke to the sound of emergency sirens blaring all over the city. No one could shut them off, and after repeated efforts to contain the situation, the city had to shut down the entire system. While the media reported a sophisticated computer hack was responsible, the truth was much less high-tech. The sirens in Dallas were controlled by a series of radio signals that weren't encrypted, and anyone could broadcast them with the right equipment. Turns out, someone simply listened in to the radio signal during a test or real emergency that triggered... more

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