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.

-Detect radio transmissions

-Identify wireless communication devices

-Track signal sources within a defined range

In this case, authorities mounted the device on a helicopter operated by the Pima County Sheriff's Department, which was seen flying low over residential areas, as per reports.

The goal: determine whether Guthrie’s pacemaker is emitting any detectable signal that could help narrow the search area.

However, modern pacemakers can:

-Wirelessly transmit medical data

-Connect to a bedside home monitor

-Sync with smartphone or smartwatch apps

-Alert heart clinics about serious cardiac events

But there are limitations:

-The device must be within range of its paired home monitor or smartphone

-It cannot transmit location data

-It cannot independently broadcast a tracking signal

-It cannot communicate without being connected to a monitoring system

Importantly, even if disconnected from an app — as authorities say Guthrie’s was shortly before she went missing — the pacemaker continues performing its core medical function.

The case has drawn national attention, including comments from Donald Trump, who said “progress has been made” in the investigation.

The sheriff’s department has received nearly 18,000 tips, released images of a masked suspect, and doubled the reward to $100,000 for information leading to her recovery or an arrest.

The FBI has also released photos and video tied to the case. The search remains ongoing.