signal recorder

例句：

1. 1. The signal recorder was used to transmit signals over long distances.
   信号记录器被用来在远距离上传输信号。
2. 2. The signal recorder was used to detect and analyze the signals from the satellite.
   信号记录器被用来检测和分析来自卫星的信号。
3. 3. The signal recorder was used to create audible signals for emergency purposes.
   信号记录器被用来创建紧急情况下的可听信号。