What is ‘signal sniffer’ that cops are using to find Nancy Guthrie pacemaker?
Authorities searching for Nancy Guthrie are deploying a piece of specialized tracking technology — commonly referred to as a “signal sniffer” — in an effort to detect emissions from her implanted pacemaker as the investigation intensifies in Tucson, Arizona. Here’s what that device is—and how it works. What is a ‘signal sniffer’? A signal sniffer…