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, NewsNation reported.
Here’s what that device is — and how it works.
What is a ‘signal sniffer’?
A signal sniffer is a radio-frequency (RF) detection device used to locate electronic signals emitted by wireless equipment. Law enforcement and search teams typically use such technology to:
-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.
Can a pacemaker be tracked?
Pacemakers are small, battery-powered devices implanted under the skin to regulate heart rhythm. They do not function as GPS trackers.
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.
Context of the search
Nancy Guthrie, 84, was reported missing on February 1 after last being seen at her home in Pima County. Authorities believe she was abducted.
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.
