auxiliary transmitter

例句：

1. 1. The auxiliary power unit is responsible for providing backup power during emergencies.
   辅助动力单元负责在紧急情况下提供备用电力。
2. 2. The auxiliary system helps to improve the efficiency of the main system.
   辅助系统有助于提高主要系统的效率。
3. 3. The auxiliary light bulb can be easily replaced with a main light bulb.
   辅助灯泡可以很容易地与主灯泡互换。