SEL-324A Speaker is a high-power microphone (including cell phone microphones) and audio recorder jammer integrated into a common ceiling speaker case, intended for manual installation primarily above desks and tables in meeting rooms.
SEL-324A "Speaker" is a high-power and efficient microphone jamming device due to its thought-out design that includes high-quality direction- al ultrasonic transducer array that pushes a complex, tailor-made noise waveform on a frequency band that is below human hearing point, but right in the zone of common audio microphone bandwidth, applying a constant noise pressure on the microphone's membrane.
An array of 24 ultrasonic transducers in the SEL-324A "Speaker" are installed in a thin (the height of the device is 40 mm) drum-shaped ceiling speaker case, providing easy deployment into ceiling speaker mounting points, that are commonly available in rooms as mounts for emergency speaker audio systems.
Due to SEL-324A ceiling mounting position, a multipath propagation effect is created, which reflects the generated noise from surfaces and items, further increasing the suppression area and efficiency.
Features
- An array of 24 high-quality piezo-ceramic transducers, controlled by a microchip that automatically shifts the noise signal in time and frequency domains, achieving best possible jamming efficiency and rendering any actual speech signal on the microphone unintelligible.
- Special power supply: device draws power from the standard ceiling speaker DC wiring: 12 V, and starts automatically whenever power is applied.
- Easy to use control: can be turned on/off via presence of power in the power supply line. Wireless RF remote control.
- Easy mounting spring brackets.
Specifications
Generated noise frequency bandwidth |
24-26 kHz |
Number of ultrasonic transducers |
24 pcs. |
Type of emission interference |
complex structured ultrasonic noise |
Microphone Suppression Directionality |
perpendicular to the plane of ultrasonic emitters |
On/off switch |
presence/absence of 12 V power in line / Remote control |
Average effective jamming range |
4 meters (Effective jamming range may vary based on type of microphone of the audio device and its relative position to the jammer ) |
Power supply |
+12 V DC |
Continuous operation time |
unlimited |
Case material |
plastic and metal |
Mounting Installation Dimensions (Minimum) |
D165x40 mm (Minimum) |
Diameter |
199 mm |
Weight |
not more than 600 g |
Operating temperature range |
0...+50 °C |
Relative humidity |
no more 85% |