Flush mounted glass break audio discriminator
The GFD-20 is an audio discriminator, sensitive to sounds above a cutoff frequency of approximately 4 kHz. When activated by such a sound, the audio discriminator energizes an on-board
output relay, that can be wired to trigger an alarm. A modified version, the GFD-20AD, is fitted with an additional potentiometer to adjust the lower cutoff frequency.
The GFD-30 glass break audio discriminator distinguishes between normal background noises and the sounds associated with forced entry intrusion. The unit is sensitive to glass breaking, wood splitting and other break-in noises, within an adjustable radius of up to 50 ft (15 m), covering an area up to 5000 square feet (500 sq m).
An advanced digital filtering technique completely rejects even very strong background noises below the cutoff frequency. State-of-the-art signal processing is employed to detect fast attack signals, yet ignores sounds that build up gradually with time, such as approaching automobiles, aircraft or screeching brakes.
All sounds affecting the detector are monitored and displayed by the "DET" LED, which actually sees what the unit hears. The GFD-30 can check the effect of individual sounds, such as ringing telephones or door chimes, and make adjustments for optimum sensitivity and maximum immunity from false alarms.
The detector is housed in an attractive compact enclosure, which can be flush mounted into walls or ceilings.
The GFD-30 is specially designed to fit into virtually any standard, single-gang, electrical switch box providing the ideal solution for pre-wired installations.
Features
- Flush mounting into single-gang electrical switch box.
- Attractive, compact, rugged design
- Detection range up to 50 ft (15 m)
- Built-in tester
- Digital filtering of unwanted noise
- Adjustable sensitivity
- 9-16 VDC operation
- Surface or ceiling mounting
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