3-channel white-noise generator

DNG-2300 protects from:

• Laser and microwave surveillance systems using reflections from the windowS
• Electronic stethoscopes (contact microphones)
• Microphones built in the walls or other constructions
• Other vibro-accousic ways of information's leakage

The DNG-2300 generator has been created to protect against listening devices which cannot be registered (found) by common methods. The unit protects room by inducting not filterable noise onto the surfaces. This noise, also known as 'white', is transmitted onto the surfaces with the help of the TRN-2000 transducers and OMS-2000 speakers. Number of transducers and speakers is dependant on the room's configurations.

Thanks to the TRN-2000 transducers the protection level of the generator is higher than the systems with the speakers only. The transducers pass most of the generated noise into the aimed construction in the form of vibration while producing less audible interference. Although a slight noise may be heard inside the protected area  there will be no need to loud your voice.

How the eavesdropping works

Vibration-acoustic leakage is possible thanks to the ability of sound waves distribute via walls,, windows and other constructions. In some materials sound distributes even better that in air. For example, water is a great conductor of sound and the heating system can be easily used for picking-up the speech. This principal is used in the electronic stethoscopes. They pick up vibrations caused by conversations on the walls, windows and other constructions and transform them back into sound. These eavesdropping devices can be installed not only in the adjacent premises but  even over a number of floors or rooms somehow connected with the interesting area - by mutual cavity or construction.

Principal of protection

The DNG-2300 can 'block' above methods. This is carried out with the help of the especial transducers. It is recommended to use the REI's TRN-2000. Their parameters are optimal for many kinds of surfaces. The TRN-2000 have good efficiency which means that only insignificant part of noise will be produced into the air while the most will be 'injected' into the construction in the form of vibration. With the help of the bracket the transducers can be mounted onto practically all kinds of surfaces.

The omni-masking speakers OMS-2000 can be also used with the DNG-2300. Their purpose is to produce not-filterable noise in the spaces like ventilations, behind the ceiling tiles, etc.

Transducers and accessories for DNG-2300

TRN-2000
Transducer
Designed for protection of walls, windows, ceilings, floors and pipes.  One transducer protects section about 3x3 meters of a wall, one window pane or a pipe of water supply or heating. Quantity in other cases may be different.

OMS-2000
Omni-masking speaker
Designed to produce not-filterable noise in the spaces like ventilations, behind the ceiling tiles, etc. Can be also used to create interference for voice recorders and other bugging devices in the internal space of the room. 

DNG-MIC
Microphone for adjusting level via the loopback channel
The DNG-2300 generator has a loopback channel. The DNG-MIC allows the user to set needed level of noise using this feature