Non-Linear Junction Detection (NLJD)

TSCM technology NLJD Non-linear Junction Detection

Non-Linear Junction Detection (NLJD) helps our technical team locate spycams and other bugging devices even when they are turned off, and even if the batteries are dead.

Non-Linear Junction Detection is a non-destructive detection technique that sees through solid objects. This eliminates the intrusive disruption a physical search sometimes requires, like checking shelves full of books. More importantly, the Non-Linear Junction Detector speeds up the detection process dramatically. Speed allows us to sweep your location expeditiously. It also allows our services to be more cost-effective for you.

How does a non-linear junction detector work?

A Non-Linear Junction Detector operates somewhat like the shoplifting detectors used by retailers. There, antennas near the doorways listen for a reflected signal from a shoplifting tag attached to an item. Interestingly, shoplifting tags do not contain batteries. They are simple devices that only contain an antenna and a diode.

Diodes are made from two dissimilar metals fused together. This creates what is called a non-linear junction. Transistors are made the same way. Non-linear junctions are the building block of all modern electronic devices, including bugs, recorders, and spycams.

How do you detect electronic devices?

When non-linear junctions are exposed to a strong radio signal, they reflect some of the original signal at twice the frequency! This phenomenon allows large areas to be scanned quickly in pursuit of the altered signal. The actual process is similar to sweeping a room with a flashlight beam. With the proper training and practice, technical investigators can use these sweeps to detect and locate the origin of all re-radiated signals.

Non-linear junction detectors are  also excellent at finding lost remote controls; very much appreciated when we inspect our clients’ residences.

Why should I use a Non-Linear Junction Detector as a part of TSCM (Technical Security Counter Measures) for my business?

It is always a very good idea to know who is listening in on private corporations, and who may have unauthorized access to information and trade secrets. As Selcom (one of the leading makers of Non-Linear Junction Detectors) explains, NLJDs were developed first for use in embassies and diplomatic settings, and quickly established their “reputation as perfect means of counter-espionage.”

Have a Question About TSCM?

If you have any questions about Non-Linear Junction Detection (NLJD) or the TSCM services provided by Murray Associates, simply fill out the form below, or call us from a safe area and phone.

If you think you are under active electronic surveillance, or believe you have discovered a bug or covert video camera, go to our Emergency TSCM page. The procedural checklist there will tell you exactly what you need to do next.