| 摘要 |
A fire alarm system having a plurality of detectors connected to a pair of conductors, a receiver and a power supply connected to said conductors and an alarm connected to the power supply and said conductors so that an alarm is sounded upon activation of a detector, each detector upon activation producing a preselected AC signal for transmission to the receiver and the receiver includes band pass filters activated by particular frequencies and having associated indicating means so that the activated detector and therefore the location of the fire or smoke can be immediately determined. |
