1．5km双向多重报警器

本电路是一种多路触发无线双向报警电路，它包括主机和随身携带的小型接收机。发射接收系统采用调频方式，使主机和小型接收机无一双向报警，最大有效接收半径1．5km。设在警戒物上的主机一旦被资贼触发报警，随身携带的接收机可在半径1．5km范围内接收主机发射的高频信号同时报，使防盗监护范围扩大到半径1．5km范围内，本电路还采用独创的多重传感触发电路，使防盗报警器安全可靠性成倍提高。

1.5 kilometres radio bidirectional barglar-proof alarm

In this paper, the alarm is a radio multipath burglar-proof alarm circuit. It ismade up of main transmitter set and small-sized radio receiver set (with you). The main transmif-fer is adopted fregueney modulation, Its radio effective radius is 1.5 kilometres. Hardly the small-sized set is worked for receiving madio from 1.5 km distance when the main set is triggered. Thealarm also is adopted a triple-sensing trigger (touching lock, breaking wire and leaving position).