Detection of electronic devices (NLJD)

How Non-Linear Junction Detection Works

A silicon junction behaves like a one-way electrical valve. When struck by a coded microwave burst, it re-radiates energy at precise multiples—harmonics—of the probe frequency. Ordinary metal reflects the original carrier with almost no harmonic content; semiconductor chips emit a strong third harmonic. An NLJD transmits, then “listens” on harmonic channels, highlighting even powered-down devices hidden behind walls, inside furniture or deep in vehicle panels.

Core Advantages

Silent-device detection – finds electronics that produce no RF emissions.
Non-destructive sweeps – no dismantling, drilling or X-ray exposure.
Universal targets – detects SIM cards, flash drives, microphones, GPS beacons and custom circuitry.
Rapid deployment – warms up in seconds and delivers visual or haptic feedback instantly.

Operational Workflow

A systematic sweep starts along perimeter walls, continues across floors and ceilings, then inspects free-standing objects. The probe is kept 10–15 cm from any surface and moved at roughly one metre per second with 50 % overlap to avoid blind strips. Output levels stay far below ICNIRP limits, ensuring safety for people, data and implants. When a harmonic spike appears, operators confirm by tilting the antenna, reducing power in 3 dB steps and verifying that the third-harmonic trace rises consistently—a signature behaviour of genuine electronics.

Typical Applications

Government offices – verify that conference rooms are free of dormant listening devices before classified briefings.
Correctional facilities – locate powered-off smartphones cemented into cell walls.
VIP travel security – clear hotel rooms, vehicles and baggage within minutes of arrival.
Vehicle inspections – expose passive trackers in bumpers, dashboards and seat backs.
Customs cargo – confirm export crates contain no embedded location beacons or tamper sensors.

Frequently Asked Questions

Is NLJD radiation safe?
Yes. Peak power is far below consumer Wi-Fi levels and will not disturb electronics or endanger people.

Can an NLJD see through solid metal?
No. Steel reflects the probe. Operators scan at seams, vents or adjacent non-metal surfaces to reach concealed areas.

Will multiple detectors interfere?
Professional units use coded pulses, so several can operate side by side without crosstalk.

How much training is required?
Basic technique is mastered in one day; a three-day OEM course covers advanced filtering and documentation.

Regulatory & Calibration Notes

NLJDs fall under EU Dual-Use category 6A008; exporting or moving them across borders requires an end-user certificate. Annual calibration against a certified junction tile keeps sensitivity within specification and protects evidential value in court.

Expose Hidden Electronics—Before They Expose You

When a silent handset or recorder could compromise security, non-linear junction detection provides the decisive safeguard. Equip your team with this harmonic-analysis technology and complete every sweep confident that no covert device remains.