| 摘要 |
The present invention relates to a communication set, in particular an alarm device, comprising a controller provided to be fixed on an object to be protected and a handset provided to be carried by a user. Signals generated by the controller are transmitted to the handset and signals generated by the handset are transmitted to the controller. These signal transmissions are performed within two different distance ranges, wherein the distance range for transmission from the controller to the handset is at least twice the transmission range from the handset to the controller.
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