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FG-1025 Family - Technical Note
Detector Intelligence Through Digital Signal Processing
The FG-730 is a “dumb” detector in that the signal is compared against three fixed thresholds.
The thresholds remain the same regardless of conditions because the thresholds are built out of
discrete components on the circuit board.
The FG-1025 family of glassbreaks are “intelligent” detectors. The software uses proprietary
mathematical formulas (algorithms) to process the signal and to adjust thresholds based on current
conditions. False alarm rejection algorithms identify and reject whole classes of false alarm sounds.
Glassbreak detection algorithms identify true glass break conditions for all glass types and attack
profiles. Thresholds are adjusted up and down as warranted by data received at the detector. In
sum, the FG-1025 family's reliability is the best on the market because it performs 20 times more
processing in the critical first 200 milliseconds of an event than that performed by the FG-730.
Patents have been filed on the FG-1025 family and its digital signal processing.
C
OMPARISON
C
HART
FG-730/930
FG-1025/1025R
FG-1025Z
flex level
flex level
flex level
audio level
audio level
audio level
timing coincidence
timing coincidence
timing coincidence
flex audio ratio
flex audio ratio
attack threshold
attack threshold
flex duration
flex duration
audio duration
audio duration
microphone overload
microphone overload
time-of-arrival
The Latest Glassbreak Innovation - FG-1025Z
The newest member of the FG-1025 family of glassbreak detectors is the FG-1025Z. This is the first
glassbreak detector that only listens for sounds coming from the glass. The FG-1025Z uses patented
Time-of-Arrival (TOA) processing which is a giant leap forward in glass break detection and false
alarm immunity for our industry. Using two microphones and TOA processing, the detector
listens only for the sound of breaking glass arriving from the glass zone (front microphone), and
ignores sounds arriving from elsewhere in the room—the excluded zone (back microphone). Other
glassbreak detectors are space protection devices because they process sounds from the room inte-
rior, as well as sounds from the perimeter glass.
FG-1025Z
