| 摘要 |
The alarm generator furnishes a coded signal which is repeated in accordance with predetermined events which may occur on the premises at which the generator is located, such as fire, burglary, and equipment failure. After a central station has been apprised of the occurrence of an event by transmitting the requisite number of rounds of the coded signal, the alarm generator is reset by transmitting another round or rounds of the coded signal such that the number of rounds sent to apprise the central station of an event plus the number of rounds sent in resetting the alarm generator is constant.
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