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|WHAT IS A NONLINEAR DETECTOR? NLJD
Nonlinear detectors ( NLJD ) are professional bug detection and bug search devices designed to search and detect eavesdropping devices, transmitters consisting of various electronic devices and semiconductors.
The working principle of NLJD equipment is based on the principle of a high emission of radio frequency energy in an area. The detectors have a sensitive receiver that is designated to analyze and receive the echo signals of the detected objects, and the detectors are designed with an audio and graphical user interface for the convenience of the user or the operator.
Depending on the model, nonlinear detectors are capable of detecting almost any electronic device in any operating mode. Devices to be detected do not need to be in standby or operating. The devices sought are all types of mini bugging devices (bugs), wireless or closed-circuit microphone systems, microphone amplifiers, voice recorders, wired or wireless hidden cameras, which may pose a risk. These devices can be found in many places (walls, floors, ceilings, furniture, etc.). Non-linear detectors are used most successfully and without alternatives for counter-espionage and detection, in order to prevent the theft of information in embassies and other diplomatic and political environments, as well as information theft and intrusion into private life.
In addition to electronic circuits, NLJDs are also used by the police to reveal devices such as weapons and similar explosive circuits in many security situations and events involving large masses.
Detectors are used in different organizations to provide a safe place for eavesdropping devices. Non-linear detectors serve multiple purposes, from being used for mobile phone detection to detecting many electronic equipment, and the application field can be in a wide range. NLJD is a prerequisite for wide search operations by material or surface type - while floor detectors are preferred for object detection in the soil, portable detectors with a suitable frequency setting may be more successful in searching wooden furniture or in-wall indoors.
The importance of setting the correct frequency of NLJD equipment for a different search environment (eg concrete walls) should not be overlooked. As an interesting fact, in the 1970s Americans detected some wires in the building pillars of the American Embassy in Moscow. These wires and electronic equipment laid during the construction of the building could not be located without the NLJD.
WORKING PRINCIPLE
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NLJD is a portable system and includes an antenna system designed in accordance with frequency values. This antenna is based on the rotation analysis system of the 2nd and 3rd harmonic frequencies of the transmitter transmitting the signal and the two antennas receiving this signal.
The mono harmonic signal emitted by the transmitter is converted into a poly harmonic signal with the help of non-linear elements and sent again. The signal level can be adjusted with the control unit on the device. The re-radiated 2nd and 3rd harmonic signals are received by the antennas again and processed and analyzed on the device. The received and analyzed signals are analyzed by the control unit and the 2nd harmonic is displayed as red and the 3rd harmonic as green on the light display.
At the same time, the generated signal is converted into sound and given audibly from the speaker or ear, thus directing the user to the result.
