Among them, there are three types of alarm speakers: electric alarm, electric sound alarm, and manual alarm. An electric alarm is a device that uses an electric motor as the main component of the alarm, converting electrical energy into sound; The electroacoustic alarm is composed of a main power amplifier and a horn speaker; The hand operated alarm is a supplementary warning device for electric and acoustic alarms.
Extended information: Air defense alerts are divided into three types: pre alert, air raid alert, and disarm alert.
Please indicate the source of the content in this article when reprinting the current fire or fuse. Answer:
1. Pre alarm: sound for 36 seconds, stop for 24 seconds, repeat 3 times for a cycle of 3 minutes. The citizens quickly evacuated to nearby underground air raid shelters, civil air raid shelters and Air raid shelter.
2. Air-Raid Siren Speaker: sound for 6 seconds, stop for 6 seconds, repeat 15 times for a cycle of 3 minutes. Citizens use terrain and features to conceal themselves nearby, lying on the ground with their hands clasping their heads.
3. Clear the alarm: a long continuous sound will be sounded for 3 minutes, and citizens can go out of the underground air raid shelter, civil air raid shelter and Air raid shelter to resume normal work.
