Audio Surveillance Detection · Recording Devices
Recording Device Detection
Detection of hidden digital voice recorders and covert audio recording devices that store audio locally without transmitting.
Unlike wireless transmitters, digital voice recorders store audio locally and produce no RF emissions — making them invisible to signal-based detection methods. These devices can be concealed inside common objects and left to record continuously for days or weeks. Empire Investigation uses physical inspection protocols and non-linear junction detection to locate hidden recording devices regardless of their transmission status.
Why Recording Devices Are Particularly Difficult to Detect
A passive digital recorder that stores audio on a local SD card or internal memory produces no signal that can be detected by standard RF sweeping equipment. These devices can be completely invisible to standard TSCM tools and require a different detection approach — combining thorough physical inspection with NLJD technology that identifies electronic components.
Common Concealment Objects for Recorders
Digital recorders are most commonly concealed inside USB power banks, wall chargers, pens, books, bags, picture frames, clocks, and everyday objects that appear completely functional and normal. Voice-activated models begin recording only when sound is detected, significantly extending battery life and making detection windows smaller.
What We Look For
- Digital voice recorders concealed in everyday objects
- Voice-activated recording devices triggered by sound
- Recorders embedded in USB chargers or power banks
- Long-duration recording devices designed for extended deployment
- Micro-SD card recorders in ultra-compact form factors
Our Sweep Process
Physical Object Inspection
Systematic examination of all objects present in the environment.
NLJD Detection
Non-linear junction detection to identify electronic components within objects.
Anomaly Documentation
Flagging of suspicious objects for further examination.
Evidence Handling
Proper evidence preservation for legal use if required.
Reporting
Comprehensive documentation of all findings.
Frequently Asked Questions
Confidential Inquiry
Schedule a Confidential TSCM Sweep
If you suspect surveillance or want to verify your environment is secure, professional detection is the only way to know with certainty.
All inquiries handled with complete discretion.